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gecko-dev/layout/generic/nsHTMLReflowState.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is Netscape Communications
* Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*/
#include "nsCOMPtr.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsFrame.h"
#include "nsIContent.h"
#include "nsHTMLAtoms.h"
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsLayoutAtoms.h"
#include "nsIDeviceContext.h"
#include "nsIRenderingContext.h"
#include "nsIFontMetrics.h"
#include "nsBlockFrame.h"
#include "nsLineBox.h"
#include "nsImageFrame.h"
#ifdef NS_DEBUG
#undef NOISY_VERTICAL_ALIGN
#else
#undef NOISY_VERTICAL_ALIGN
#endif
// Initialize a <b>root</b> reflow state with a rendering context to
// use for measuring things.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsReflowReason aReason,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace)
: mReflowDepth(0)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
parentReflowState = nsnull;
frame = aFrame;
reason = aReason;
reflowCommand = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aRenderingContext;
mSpaceManager = nsnull;
mLineLayout = nsnull;
isTopOfPage = PR_FALSE;
Init(aPresContext);
}
// Initialize a <b>root</b> reflow state for an <b>incremental</b>
// reflow.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsIReflowCommand& aReflowCommand,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace)
: mReflowDepth(0)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
reason = eReflowReason_Incremental;
parentReflowState = nsnull;
frame = aFrame;
reflowCommand = &aReflowCommand;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aRenderingContext;
mSpaceManager = nsnull;
mLineLayout = nsnull;
isTopOfPage = PR_FALSE;
Init(aPresContext);
}
// Initialize a reflow state for a child frames reflow. Some state
// is copied from the parent reflow state; the remaining state is
// computed.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nsReflowReason aReason)
: mReflowDepth(aParentReflowState.mReflowDepth + 1)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aReason;
reflowCommand = (reason == eReflowReason_Incremental)
? aParentReflowState.reflowCommand
: nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
isTopOfPage = aParentReflowState.isTopOfPage;
Init(aPresContext);
}
// Same as the previous except that the reason is taken from the
// parent's reflow state.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace)
: mReflowDepth(aParentReflowState.mReflowDepth + 1)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aParentReflowState.reason;
reflowCommand = aParentReflowState.reflowCommand;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
isTopOfPage = aParentReflowState.isTopOfPage;
Init(aPresContext);
}
// Version that species the containing block width and height
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
: mReflowDepth(aParentReflowState.mReflowDepth + 1)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aParentReflowState.reason;
reflowCommand = aParentReflowState.reflowCommand;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
isTopOfPage = aParentReflowState.isTopOfPage;
Init(aPresContext, aContainingBlockWidth, aContainingBlockHeight);
}
void
nsHTMLReflowState::Init(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
mCompactMarginWidth = 0;
mAlignCharOffset = 0;
mUseAlignCharOffset = 0;
frame->GetStyleData(eStyleStruct_Position,
(const nsStyleStruct*&)mStylePosition);
frame->GetStyleData(eStyleStruct_Display,
(const nsStyleStruct*&)mStyleDisplay);
frame->GetStyleData(eStyleStruct_Spacing,
(const nsStyleStruct*&)mStyleSpacing);
frame->GetStyleData(eStyleStruct_Text,
(const nsStyleStruct*&)mStyleText);
mFrameType = DetermineFrameType(frame, mStylePosition, mStyleDisplay);
InitConstraints(aPresContext, aContainingBlockWidth, aContainingBlockHeight);
}
const nsHTMLReflowState*
nsHTMLReflowState::GetContainingBlockReflowState(const nsHTMLReflowState* aParentRS)
{
while (nsnull != aParentRS) {
if (nsnull != aParentRS->frame) {
PRBool isContainingBlock;
// XXX This needs to go and we need to start using the info in the
// reflow state...
nsresult rv = aParentRS->frame->IsPercentageBase(isContainingBlock);
if (NS_SUCCEEDED(rv) && isContainingBlock) {
// a block inside a table cell needs to use the table cell
if (aParentRS->parentReflowState) {
nsCOMPtr<nsIAtom> fType;
aParentRS->parentReflowState->frame->GetFrameType(getter_AddRefs(fType));
if (nsLayoutAtoms::tableCellFrame == fType.get()) {
aParentRS = aParentRS->parentReflowState;
}
}
return aParentRS;
}
}
aParentRS = aParentRS->parentReflowState;
}
return nsnull;
}
const nsHTMLReflowState*
nsHTMLReflowState::GetPageBoxReflowState(const nsHTMLReflowState* aParentRS)
{
// XXX write me as soon as we can ask a frame if it's a page frame...
return nsnull;
}
nscoord
nsHTMLReflowState::GetContainingBlockContentWidth(const nsHTMLReflowState* aParentRS)
{
nscoord width = 0;
const nsHTMLReflowState* rs =
GetContainingBlockReflowState(aParentRS);
if (nsnull != rs) {
return aParentRS->mComputedWidth;
}
return width;
}
nsCSSFrameType
nsHTMLReflowState::DetermineFrameType(nsIFrame* aFrame)
{
const nsStylePosition* stylePosition;
aFrame->GetStyleData(eStyleStruct_Position,
(const nsStyleStruct*&)stylePosition);
const nsStyleDisplay* styleDisplay;
aFrame->GetStyleData(eStyleStruct_Display,
(const nsStyleStruct*&)styleDisplay);
return DetermineFrameType(aFrame, stylePosition, styleDisplay);
}
nsCSSFrameType
nsHTMLReflowState::DetermineFrameType(nsIFrame* aFrame,
const nsStylePosition* aPosition,
const nsStyleDisplay* aDisplay)
{
nsCSSFrameType frameType;
// Get the frame state
nsFrameState frameState;
aFrame->GetFrameState(&frameState);
// Section 9.7 of the CSS2 spec indicates that absolute position
// takes precedence over float which takes precedence over display.
// Make sure the frame was actually moved out of the flow, and don't
// just assume what the style says
if (frameState & NS_FRAME_OUT_OF_FLOW) {
if (aPosition->IsAbsolutelyPositioned()) {
frameType = NS_CSS_FRAME_TYPE_ABSOLUTE;
}
else if (NS_STYLE_FLOAT_NONE != aDisplay->mFloats) {
frameType = NS_CSS_FRAME_TYPE_FLOATING;
}
}
else {
switch (aDisplay->mDisplay) {
case NS_STYLE_DISPLAY_BLOCK:
case NS_STYLE_DISPLAY_LIST_ITEM:
case NS_STYLE_DISPLAY_TABLE:
case NS_STYLE_DISPLAY_TABLE_CAPTION:
frameType = NS_CSS_FRAME_TYPE_BLOCK;
break;
case NS_STYLE_DISPLAY_INLINE:
case NS_STYLE_DISPLAY_MARKER:
case NS_STYLE_DISPLAY_INLINE_TABLE:
frameType = NS_CSS_FRAME_TYPE_INLINE;
break;
case NS_STYLE_DISPLAY_RUN_IN:
case NS_STYLE_DISPLAY_COMPACT:
// XXX need to look ahead at the frame's sibling
frameType = NS_CSS_FRAME_TYPE_BLOCK;
break;
case NS_STYLE_DISPLAY_TABLE_CELL:
case NS_STYLE_DISPLAY_TABLE_ROW_GROUP:
case NS_STYLE_DISPLAY_TABLE_COLUMN:
case NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP:
case NS_STYLE_DISPLAY_TABLE_HEADER_GROUP:
case NS_STYLE_DISPLAY_TABLE_FOOTER_GROUP:
case NS_STYLE_DISPLAY_TABLE_ROW:
frameType = NS_CSS_FRAME_TYPE_INTERNAL_TABLE;
break;
case NS_STYLE_DISPLAY_NONE:
default:
frameType = NS_CSS_FRAME_TYPE_UNKNOWN;
break;
}
}
// See if the frame is replaced
if (frameState & NS_FRAME_REPLACED_ELEMENT) {
frameType = NS_FRAME_REPLACED(frameType);
}
return frameType;
}
void
nsHTMLReflowState::ComputeRelativeOffsets(const nsHTMLReflowState* cbrs,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
nsStyleCoord coord;
// Compute the 'left' and 'right' values. 'Left' moves the boxes to the right,
// and 'right' moves the boxes to the left. The computed values are always:
// left=-right
PRBool leftIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit();
PRBool rightIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit();
// Check for percentage based values and an unconstrained containing
// block width. Treat them like 'auto'
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
if (eStyleUnit_Percent == mStylePosition->mOffset.GetLeftUnit()) {
leftIsAuto = PR_TRUE;
}
if (eStyleUnit_Percent == mStylePosition->mOffset.GetRightUnit()) {
rightIsAuto = PR_TRUE;
}
}
// If neither 'left' not 'right' are auto, then we're over-constrained and
// we ignore one of them
if (!leftIsAuto && !rightIsAuto) {
const nsStyleDisplay* display;
frame->GetStyleData(eStyleStruct_Display, (const nsStyleStruct*&)display);
if (NS_STYLE_DIRECTION_LTR == display->mDirection) {
rightIsAuto = PR_TRUE;
} else {
leftIsAuto = PR_TRUE;
}
}
if (leftIsAuto) {
if (rightIsAuto) {
// If both are 'auto' (their initial values), the computed values are 0
mComputedOffsets.left = mComputedOffsets.right = 0;
} else {
// 'Right' isn't 'auto' so compute its value
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetRightUnit()) {
mComputedOffsets.right = cbrs->mComputedOffsets.right;
} else {
ComputeHorizontalValue(aContainingBlockWidth, mStylePosition->mOffset.GetRightUnit(),
mStylePosition->mOffset.GetRight(coord),
mComputedOffsets.right);
}
// Computed value for 'left' is minus the value of 'right'
mComputedOffsets.left = -mComputedOffsets.right;
}
} else {
NS_ASSERTION(rightIsAuto, "unexpected specified constraint");
// 'Left' isn't 'auto' so compute its value
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetLeftUnit()) {
mComputedOffsets.left = cbrs->mComputedOffsets.left;
} else {
ComputeHorizontalValue(aContainingBlockWidth, mStylePosition->mOffset.GetLeftUnit(),
mStylePosition->mOffset.GetLeft(coord),
mComputedOffsets.left);
}
// Computed value for 'right' is minus the value of 'left'
mComputedOffsets.right = -mComputedOffsets.left;
}
// Compute the 'top' and 'bottom' values. The 'top' and 'bottom' properties
// move relatively positioned elements up and down. They also must be each
// other's negative
PRBool topIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit();
PRBool bottomIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit();
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
if (eStyleUnit_Percent == mStylePosition->mOffset.GetTopUnit()) {
topIsAuto = PR_TRUE;
}
if (eStyleUnit_Percent == mStylePosition->mOffset.GetBottomUnit()) {
bottomIsAuto = PR_TRUE;
}
}
// If neither is 'auto', 'bottom' is ignored
if (!topIsAuto && !bottomIsAuto) {
bottomIsAuto = PR_TRUE;
}
if (topIsAuto) {
if (bottomIsAuto) {
// If both are 'auto' (their initial values), the computed values are 0
mComputedOffsets.top = mComputedOffsets.bottom = 0;
} else {
// 'Bottom' isn't 'auto' so compute its value
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetBottomUnit()) {
mComputedOffsets.bottom = cbrs->mComputedOffsets.bottom;
} else {
ComputeVerticalValue(aContainingBlockHeight, mStylePosition->mOffset.GetBottomUnit(),
mStylePosition->mOffset.GetBottom(coord),
mComputedOffsets.bottom);
}
// Computed value for 'top' is minus the value of 'bottom'
mComputedOffsets.top = -mComputedOffsets.bottom;
}
} else {
NS_ASSERTION(bottomIsAuto, "unexpected specified constraint");
// 'Top' isn't 'auto' so compute its value
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetTopUnit()) {
mComputedOffsets.top = cbrs->mComputedOffsets.top;
} else {
ComputeVerticalValue(aContainingBlockHeight, mStylePosition->mOffset.GetTopUnit(),
mStylePosition->mOffset.GetTop(coord),
mComputedOffsets.top);
}
// Computed value for 'bottom' is minus the value of 'top'
mComputedOffsets.bottom = -mComputedOffsets.top;
}
}
// Returns the nearest containing block frame for the specified frame.
// Also returns the left, top, right, and bottom edges of the specified
// frame's content area. These are in the coordinate space of the block
// frame itself
static nsIFrame*
GetNearestContainingBlock(nsIFrame* aFrame, nsMargin& aContentArea)
{
aFrame->GetParent(&aFrame);
while (aFrame) {
nsIAtom* frameType;
PRBool isBlock;
aFrame->GetFrameType(&frameType);
isBlock = (frameType == nsLayoutAtoms::blockFrame) ||
(frameType == nsLayoutAtoms::areaFrame);
NS_IF_RELEASE(frameType);
if (isBlock) {
break;
}
aFrame->GetParent(&aFrame);
}
if (aFrame) {
nsSize size;
aFrame->GetSize(size);
aContentArea.left = 0;
aContentArea.top = 0;
aContentArea.right = size.width;
aContentArea.bottom = size.height;
// Subtract off for border and padding. If it can't be computed because
// it's percentage based (for example) then just ignore it
nsStyleSpacing* spacing;
nsMargin borderPadding;
aFrame->GetStyleData(eStyleStruct_Spacing, (const nsStyleStruct*&)spacing);
if (spacing->GetBorderPadding(borderPadding)) {
aContentArea.left += borderPadding.left;
aContentArea.top += borderPadding.top;
aContentArea.right -= borderPadding.right;
aContentArea.bottom -= borderPadding.bottom;
}
}
return aFrame;
}
// When determining the hypothetical box that would have been if the element
// had been in the flow we may not be able to exactly determine both the left
// and right edges. For example, if the element is a non-replaced inline-level
// element we would have to reflow it in order to determine it desired width.
// In that case depending on the progression direction either the left or
// right edge would be marked as not being exact
struct nsHypotheticalBox {
nscoord mLeft, mRight;
nscoord mTop;
PRPackedBool mLeftIsExact, mRightIsExact;
nsHypotheticalBox() {
mLeftIsExact = mRightIsExact = PR_FALSE;
}
};
static PRBool
GetIntrinsicSizeFor(nsIFrame* aFrame, nsSize& aIntrinsicSize)
{
// See if it is an image frame
nsIAtom* frameType;
PRBool result = PR_FALSE;
// Currently the only type of replaced frame that we can get the intrinsic
// size for is an image frame
// XXX We should add back the GetReflowMetrics() function and one of the
// things should be the intrinsic size...
aFrame->GetFrameType(&frameType);
if (frameType == nsLayoutAtoms::imageFrame) {
nsImageFrame* imageFrame = (nsImageFrame*)aFrame;
imageFrame->GetIntrinsicImageSize(aIntrinsicSize);
result = (aIntrinsicSize != nsSize(0, 0));
}
NS_IF_RELEASE(frameType);
return result;
}
nscoord
nsHTMLReflowState::CalculateHorizBorderPaddingMargin(nscoord aContainingBlockWidth)
{
nsMargin border, padding, margin;
// Get the border
if (!mStyleSpacing->GetBorder(border)) {
// CSS2 has no percentage borders
border.SizeTo(0, 0, 0, 0);
}
// See if the style system can provide us the padding directly
if (!mStyleSpacing->GetPadding(padding)) {
nsStyleCoord left, right;
// We have to compute the left and right values
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetLeftUnit()) {
padding.left = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetLeftUnit(),
mStyleSpacing->mPadding.GetLeft(left),
padding.left);
}
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetRightUnit()) {
padding.right = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetRightUnit(),
mStyleSpacing->mPadding.GetRight(right),
padding.right);
}
}
// See if the style system can provide us the margin directly
if (!mStyleSpacing->GetMargin(margin)) {
nsStyleCoord left, right;
// We have to compute the left and right values
if ((eStyleUnit_Auto == mStyleSpacing->mMargin.GetLeftUnit()) ||
(eStyleUnit_Inherit == mStyleSpacing->mMargin.GetLeftUnit())) {
margin.left = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetLeftUnit(),
mStyleSpacing->mMargin.GetLeft(left),
margin.left);
}
if ((eStyleUnit_Auto == mStyleSpacing->mMargin.GetRightUnit()) ||
(eStyleUnit_Inherit == mStyleSpacing->mMargin.GetRightUnit())) {
margin.right = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetRightUnit(),
mStyleSpacing->mMargin.GetRight(right),
margin.right);
}
}
return padding.left + padding.right + border.left + border.right +
margin.left + margin.right;
}
static void
GetPlaceholderOffset(nsIFrame* aPlaceholderFrame,
nsIFrame* aBlockFrame,
nsPoint& aOffset)
{
aPlaceholderFrame->GetOrigin(aOffset);
// Convert the placeholder position to the coordinate space of the block
// frame that contains it
nsIFrame* parent;
aPlaceholderFrame->GetParent(&parent);
while (parent && (parent != aBlockFrame)) {
nsPoint origin;
parent->GetOrigin(origin);
aOffset += origin;
parent->GetParent(&parent);
}
}
static nsIFrame*
FindImmediateChildOf(nsIFrame* aParent, nsIFrame* aDescendantFrame)
{
nsIFrame* result = aDescendantFrame;
while (result) {
nsIFrame* parent;
result->GetParent(&parent);
if (parent == aParent) {
break;
}
// The frame is not an immediate child of aParent so walk up another level
result = parent;
}
return result;
}
// Calculate the hypothetical box that the element would have if it were in
// the flow. The values returned are relative to the padding edge of the
// absolute containing block
void
nsHTMLReflowState::CalculateHypotheticalBox(nsIPresContext* aPresContext,
nsIFrame* aPlaceholderFrame,
nsIFrame* aBlockFrame,
nsMargin& aBlockContentArea,
nsIFrame* aAbsoluteContainingBlockFrame,
nsHypotheticalBox& aHypotheticalBox)
{
// If it's a replaced element and it has a 'auto' value for 'width', see if we
// can get the intrinsic size. This will allow us to exactly determine both the
// left and right edges
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
nsSize intrinsicSize;
PRBool knowIntrinsicSize = PR_FALSE;
if (NS_FRAME_IS_REPLACED(mFrameType) && (eStyleUnit_Auto == widthUnit)) {
// See if we can get the intrinsic size of the element
knowIntrinsicSize = GetIntrinsicSizeFor(frame, intrinsicSize);
}
// See if we can calculate what the box width would have been if the
// element had been in the flow
nscoord boxWidth;
PRBool knowBoxWidth = PR_FALSE;
if ((NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mDisplay) &&
!NS_FRAME_IS_REPLACED(mFrameType)) {
// For non-replaced inline-level elements the 'width' property doesn't apply,
// so we don't know what the width would have been without reflowing it
} else {
// It's either a replaced inline-level element or a block-level element
nscoord horizBorderPaddingMargin;
// Determine the total amount of horizontal border/padding/margin that
// the element would have had if it had been in the flow. Note that we
// ignore any 'auto' and 'inherit' values
horizBorderPaddingMargin = CalculateHorizBorderPaddingMargin(aBlockContentArea.right -
aBlockContentArea.left);
if (NS_FRAME_IS_REPLACED(mFrameType) && (eStyleUnit_Auto == widthUnit)) {
// It's a replaced element with an 'auto' width so the box width is
// its intrinsic size plus any border/padding/margin
if (knowIntrinsicSize) {
boxWidth = intrinsicSize.width + horizBorderPaddingMargin;
knowBoxWidth = PR_TRUE;
}
} else if ((eStyleUnit_Inherit == widthUnit) || (eStyleUnit_Auto == widthUnit)) {
// The box width is the containing block width
boxWidth = aBlockContentArea.right - aBlockContentArea.left;
knowBoxWidth = PR_TRUE;
} else {
// We need to compute it. It's important we do this, because if it's
// percentage based this computed value may be different from the comnputed
// value calculated using the absolute containing block width
ComputeHorizontalValue(aBlockContentArea.right - aBlockContentArea.left,
widthUnit, mStylePosition->mWidth, boxWidth);
boxWidth += horizBorderPaddingMargin;
knowBoxWidth = PR_TRUE;
}
}
// Get the 'direction' of the block
const nsStyleDisplay* blockDisplay;
aBlockFrame->GetStyleData(eStyleStruct_Display, (const nsStyleStruct*&)blockDisplay);
// How we determine the hypothetical box depends on whether the element
// would have been inline-level or block-level
if (NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mDisplay) {
nsPoint placeholderOffset;
// Get the placeholder x-offset and y-offset in the coordinate
// space of the block frame that contains it
GetPlaceholderOffset(aPlaceholderFrame, aBlockFrame, placeholderOffset);
// The y-offset is the baseline of where the text would be if it were
// in the flow. We need the top position and not the baseline position
nsIFontMetrics* metrics;
const nsStyleFont* font;
frame->GetStyleData(eStyleStruct_Font, (const nsStyleStruct*&)font);
aPresContext->GetMetricsFor(font->mFont, &metrics);
if (metrics) {
nscoord ascent;
// Adjust the y-offset up by the font ascent. That will translate from
// the baseline to the top of where the text would be
metrics->GetMaxAscent(ascent);
placeholderOffset.y -= ascent;
NS_RELEASE(metrics);
}
aHypotheticalBox.mTop = placeholderOffset.y;
// To determine the left and right offsets we need to look at the block's 'direction'
if (NS_STYLE_DIRECTION_LTR == blockDisplay->mDirection) {
// The placeholder represents the left edge of the hypothetical box
aHypotheticalBox.mLeft = placeholderOffset.x;
aHypotheticalBox.mLeftIsExact = PR_TRUE;
if (knowBoxWidth) {
aHypotheticalBox.mRight = aHypotheticalBox.mLeft + boxWidth;
aHypotheticalBox.mRightIsExact = PR_TRUE;
} else {
// We can't compute the right edge because we don't know the desired
// width. So instead use the right content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mRight = aBlockContentArea.right;
aHypotheticalBox.mRightIsExact = PR_FALSE;
}
} else {
// The placeholder represents the right edge of the hypothetical box
aHypotheticalBox.mRight = placeholderOffset.x;
aHypotheticalBox.mRightIsExact = PR_TRUE;
if (knowBoxWidth) {
aHypotheticalBox.mLeft = aHypotheticalBox.mRight - boxWidth;
aHypotheticalBox.mLeftIsExact = PR_TRUE;
} else {
// We can't compute the left edge because we don't know the desired
// width. So instead use the left content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mLeft = aBlockContentArea.left;
aHypotheticalBox.mLeftIsExact = PR_FALSE;
}
}
} else {
// The element would have been block-level which means it would be below
// the line containing the placeholder frame
if (aBlockFrame) {
nsIFrame* blockChild;
nsLineBox* lineBox;
nsLineBox* prevLineBox;
PRBool isFloater;
// We need the immediate child of the block frame, and that may not be
// the placeholder frame
blockChild = FindImmediateChildOf(aBlockFrame, aPlaceholderFrame);
lineBox = ((nsBlockFrame*)aBlockFrame)->FindLineFor(blockChild, &prevLineBox,
&isFloater);
if (lineBox) {
// The top of the hypothetical box is just below the line containing
// the placeholder
aHypotheticalBox.mTop = lineBox->mBounds.YMost();
} else {
nsPoint placeholderOffset;
// Just use the placeholder's y-offset
GetPlaceholderOffset(aPlaceholderFrame, aBlockFrame, placeholderOffset);
aHypotheticalBox.mTop = placeholderOffset.y;
}
}
// To determine the left and right offsets we need to look at the block's 'direction'
if (NS_STYLE_DIRECTION_LTR == blockDisplay->mDirection) {
aHypotheticalBox.mLeft = aBlockContentArea.left;
aHypotheticalBox.mLeftIsExact = PR_TRUE;
// If we know the box width then we can determine the right edge
if (knowBoxWidth) {
aHypotheticalBox.mRight = aHypotheticalBox.mLeft + boxWidth;
aHypotheticalBox.mRightIsExact = PR_TRUE;
} else {
// We can't compute the right edge because we don't know the intrinsic
// width yet. So instead use the right content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mRight = aBlockContentArea.right;
aHypotheticalBox.mRightIsExact = PR_FALSE;
}
} else {
aHypotheticalBox.mRight = aBlockContentArea.right;
aHypotheticalBox.mRightIsExact = PR_TRUE;
// If we know the box width then we can determine the left edge
if (knowBoxWidth) {
aHypotheticalBox.mLeft = aHypotheticalBox.mRight - boxWidth;
aHypotheticalBox.mLeftIsExact = PR_TRUE;
} else {
// We can't compute the left edge because we don't know the intrinsic
// width yet. So instead use the left content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mLeft = aBlockContentArea.left;
aHypotheticalBox.mLeftIsExact = PR_FALSE;
}
}
}
// The current coordinate space is that of the nearest block to the placeholder.
// Convert to the coordinate space of the absolute containing block
if (aBlockFrame != aAbsoluteContainingBlockFrame) {
nsIFrame* parent = aBlockFrame;
do {
nsPoint origin;
parent->GetOrigin(origin);
aHypotheticalBox.mLeft += origin.x;
aHypotheticalBox.mRight += origin.x;
aHypotheticalBox.mTop += origin.y;
// Move up the tree one level
parent->GetParent(&parent);
} while (parent && (parent != aAbsoluteContainingBlockFrame));
}
// The specified offsets are relative to the absolute containing block's padding
// edge, and our current values are relative to the border edge so translate
nsMargin border;
const nsStyleSpacing* spacing;
aAbsoluteContainingBlockFrame->GetStyleData(eStyleStruct_Spacing, (const nsStyleStruct*&)spacing);
if (!spacing->GetBorder(border)) {
NS_NOTYETIMPLEMENTED("percentage border");
}
aHypotheticalBox.mLeft -= border.left;
aHypotheticalBox.mRight -= border.left;
aHypotheticalBox.mTop -= border.top;
}
void
nsHTMLReflowState::InitAbsoluteConstraints(nsIPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nscoord containingBlockWidth,
nscoord containingBlockHeight)
{
NS_PRECONDITION(containingBlockHeight != NS_AUTOHEIGHT,
"containing block height must be constrained");
// Get the placeholder frame
nsIFrame* placeholderFrame;
nsCOMPtr<nsIPresShell> presShell;
aPresContext->GetShell(getter_AddRefs(presShell));
presShell->GetPlaceholderFrameFor(frame, &placeholderFrame);
NS_ASSERTION(nsnull != placeholderFrame, "no placeholder frame");
// Find the nearest containing block frame to the placeholder frame,
// and return its content area left, top, right, and bottom edges
nsMargin blockContentArea;
nsIFrame* blockFrame = GetNearestContainingBlock(placeholderFrame,
blockContentArea);
// If both 'left' and 'right' are 'auto' or both 'top' and 'bottom' are
// 'auto', then compute the hypothetical box of where the element would
// have been if it had been in the flow
nsHypotheticalBox hypotheticalBox;
if (((eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit()) &&
(eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit())) ||
((eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit()) &&
(eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit()))) {
CalculateHypotheticalBox(aPresContext, placeholderFrame, blockFrame,
blockContentArea, cbrs->frame, hypotheticalBox);
}
// Initialize the 'left' and 'right' computed offsets
// XXX Handle new 'static-position' value...
PRBool leftIsAuto = PR_FALSE, rightIsAuto = PR_FALSE;
nsStyleCoord coord;
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetLeftUnit()) {
mComputedOffsets.left = cbrs->mComputedOffsets.left;
} else if (eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit()) {
mComputedOffsets.left = 0;
leftIsAuto = PR_TRUE;
} else {
ComputeHorizontalValue(containingBlockWidth, mStylePosition->mOffset.GetLeftUnit(),
mStylePosition->mOffset.GetLeft(coord),
mComputedOffsets.left);
}
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetRightUnit()) {
mComputedOffsets.right = cbrs->mComputedOffsets.right;
} else if (eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit()) {
mComputedOffsets.right = 0;
rightIsAuto = PR_TRUE;
} else {
ComputeHorizontalValue(containingBlockWidth, mStylePosition->mOffset.GetRightUnit(),
mStylePosition->mOffset.GetRight(coord),
mComputedOffsets.right);
}
// When the CSS2 spec refers to direction it means the containing block's
// direction and not the direction of the absolutely positioned element itself
PRUint8 direction = cbrs->mStyleDisplay->mDirection;
// Initialize the 'width' computed value
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
PRBool widthIsAuto = (eStyleUnit_Auto == widthUnit);
if (!widthIsAuto) {
if (eStyleUnit_Inherit == widthUnit) {
// The inherited value comes from the parent and not the absolute
// containing block
mComputedWidth = blockContentArea.right - blockContentArea.left;
} else {
// Use the specified value for the computed width
ComputeHorizontalValue(containingBlockWidth, widthUnit,
mStylePosition->mWidth, mComputedWidth);
}
// Factor in any minimum and maximum size information
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
}
// See if none of 'left', 'width', and 'right', is 'auto'
if (!leftIsAuto && !widthIsAuto && !rightIsAuto) {
// See whether we're over-constrained
PRInt32 availBoxSpace = containingBlockWidth - mComputedOffsets.left - mComputedOffsets.right;
PRInt32 availContentSpace = availBoxSpace - mComputedBorderPadding.left -
mComputedBorderPadding.right;
if (availContentSpace < mComputedWidth) {
// We're over-constrained so use 'direction' to dictate which value to
// ignore
if (NS_STYLE_DIRECTION_LTR == direction) {
// Ignore the specified value for 'right'
mComputedOffsets.right = containingBlockWidth - mComputedOffsets.left -
mComputedBorderPadding.left - mComputedWidth - mComputedBorderPadding.right;
} else {
// Ignore the specified value for 'left'
mComputedOffsets.left = containingBlockWidth - mComputedBorderPadding.left -
mComputedWidth - mComputedBorderPadding.right - mComputedOffsets.right;
}
} else {
// Calculate any 'auto' margin values
PRBool marginLeftIsAuto = (eStyleUnit_Auto == mStyleSpacing->mMargin.GetLeftUnit());
PRBool marginRightIsAuto = (eStyleUnit_Auto == mStyleSpacing->mMargin.GetRightUnit());
PRInt32 availMarginSpace = availContentSpace - mComputedWidth;
if (marginLeftIsAuto) {
if (marginRightIsAuto) {
// Both 'margin-left' and 'margin-right' are 'auto', so they get
// equal values
mComputedMargin.left = availMarginSpace / 2;
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
} else {
// Just 'margin-left' is 'auto'
mComputedMargin.left = availMarginSpace - mComputedMargin.right;
}
} else {
// Just 'margin-right' is 'auto'
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
}
}
} else {
// See if all three of 'left', 'width', and 'right', are 'auto'
if (leftIsAuto && widthIsAuto && rightIsAuto) {
// Use the 'direction' to dictate whether 'left' or 'right' is
// treated like 'static-position'
if (NS_STYLE_DIRECTION_LTR == direction) {
if (hypotheticalBox.mLeftIsExact) {
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
} else {
// Well, we don't know 'left' so we have to use 'right' and
// then solve for 'left'
mComputedOffsets.right = hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
}
} else {
if (hypotheticalBox.mRightIsExact) {
mComputedOffsets.right = containingBlockWidth - hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
} else {
// Well, we don't know 'right' so we have to use 'left' and
// then solve for 'right'
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
}
}
}
// At this point we know that at least one of 'left', 'width', and 'right'
// is 'auto', but not all three. Examine the various combinations
if (widthIsAuto) {
if (leftIsAuto || rightIsAuto) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For a replaced element we use the intrinsic size
mComputedWidth = NS_INTRINSICSIZE;
} else {
// The width is shrink-to-fit but constrained by the containing block width
mComputedWidth = NS_SHRINKWRAPWIDTH;
PRInt32 maxWidth = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left -
mComputedBorderPadding.right - mComputedMargin.right -
mComputedOffsets.right;
if (maxWidth <= 0) {
maxWidth = 1;
}
if (mComputedMaxWidth > maxWidth) {
mComputedMaxWidth = maxWidth;
}
}
if (leftIsAuto) {
mComputedOffsets.left = NS_AUTOOFFSET; // solve for 'left'
} else {
mComputedOffsets.right = NS_AUTOOFFSET; // solve for 'right'
}
} else {
// Only 'width' is 'auto' so just solve for 'width'
mComputedWidth = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left -
mComputedBorderPadding.right -
mComputedMargin.right - mComputedOffsets.right;
// Factor in any minimum and maximum size information
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
// XXX If the direction is rtl then we need to reevaluate left...
}
} else {
// Either 'left' or 'right' or both is 'auto'
if (leftIsAuto && rightIsAuto) {
// Use the 'direction' to dictate whether 'left' or 'right' is treated like
// 'static-position'
if (NS_STYLE_DIRECTION_LTR == direction) {
if (hypotheticalBox.mLeftIsExact) {
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
} else {
// Well, we don't know 'left' so we have to use 'right' and
// then solve for 'left'
mComputedOffsets.right = hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
}
} else {
if (hypotheticalBox.mRightIsExact) {
mComputedOffsets.right = containingBlockWidth - hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
} else {
// Well, we don't know 'right' so we have to use 'left' and
// then solve for 'right'
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
}
}
}
if (leftIsAuto) {
// Solve for 'left'
mComputedOffsets.left = containingBlockWidth - mComputedMargin.left -
mComputedBorderPadding.left - mComputedWidth - mComputedBorderPadding.right -
mComputedMargin.right - mComputedOffsets.right;
} else if (rightIsAuto) {
// Solve for 'right'
mComputedOffsets.right = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left - mComputedWidth -
mComputedBorderPadding.right - mComputedMargin.right;
}
}
}
// Initialize the 'top' and 'bottom' computed offsets
nsStyleUnit heightUnit = mStylePosition->mHeight.GetUnit();
PRBool topIsAuto = PR_FALSE, bottomIsAuto = PR_FALSE;
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetTopUnit()) {
mComputedOffsets.top = cbrs->mComputedOffsets.top;
} else if (eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit()) {
mComputedOffsets.top = 0;
topIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeVerticalValue(containingBlockHeight,
mStylePosition->mOffset.GetTopUnit(),
mStylePosition->mOffset.GetTop(c),
mComputedOffsets.top);
}
if (eStyleUnit_Inherit == mStylePosition->mOffset.GetBottomUnit()) {
mComputedOffsets.bottom = cbrs->mComputedOffsets.bottom;
} else if (eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit()) {
mComputedOffsets.bottom = 0;
bottomIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeVerticalValue(containingBlockHeight,
mStylePosition->mOffset.GetBottomUnit(),
mStylePosition->mOffset.GetBottom(c),
mComputedOffsets.bottom);
}
// Initialize the 'height' computed value
PRBool heightIsAuto = (eStyleUnit_Auto == heightUnit);
if (!heightIsAuto) {
if (eStyleUnit_Inherit == heightUnit) {
// The inherited value comes from the parent and not the absolute
// containing block
mComputedHeight = blockContentArea.bottom - blockContentArea.top;
} else {
// Use the specified value for the computed height
// XXX Handle 'inherit'. The inherited value comes from the parent
// and not the containing block
ComputeVerticalValue(containingBlockHeight, heightUnit,
mStylePosition->mHeight, mComputedHeight);
}
// Factor in any minimum and maximum size information
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
}
// See if none of 'top', 'height', and 'bottom', is 'auto'
if (!topIsAuto && !heightIsAuto && !bottomIsAuto) {
// See whether we're over-constrained
PRInt32 availBoxSpace = containingBlockHeight - mComputedOffsets.top - mComputedOffsets.bottom;
PRInt32 availContentSpace = availBoxSpace - mComputedBorderPadding.top -
mComputedBorderPadding.bottom;
if (availContentSpace < mComputedHeight) {
// We're over-constrained so ignore the specified value for 'bottom'
mComputedOffsets.bottom = containingBlockHeight - mComputedOffsets.top -
mComputedBorderPadding.top - mComputedHeight - mComputedBorderPadding.bottom;
} else {
// Calculate any 'auto' margin values
PRBool marginTopIsAuto = (eStyleUnit_Auto == mStyleSpacing->mMargin.GetTopUnit());
PRBool marginBottomIsAuto = (eStyleUnit_Auto == mStyleSpacing->mMargin.GetBottomUnit());
PRInt32 availMarginSpace = availContentSpace - mComputedHeight;
if (marginTopIsAuto) {
if (marginBottomIsAuto) {
// Both 'margin-top' and 'margin-bottom' are 'auto', so they get
// equal values
mComputedMargin.top = availMarginSpace / 2;
mComputedMargin.bottom = availMarginSpace - mComputedMargin.top;
} else {
// Just 'margin-top' is 'auto'
mComputedMargin.top = availMarginSpace - mComputedMargin.bottom;
}
} else {
// Just 'margin-bottom' is 'auto'
mComputedMargin.bottom = availMarginSpace - mComputedMargin.top;
}
}
} else {
// See if all three of 'top', 'height', and 'bottom', are 'auto'
if (topIsAuto && heightIsAuto && bottomIsAuto) {
// Treat 'top' like 'static-position'
mComputedOffsets.top = hypotheticalBox.mTop;
topIsAuto = PR_FALSE;
}
// At this point we know that at least one of 'top', 'height', and 'bottom'
// is 'auto', but not all three. Examine the various combinations
if (heightIsAuto) {
if (topIsAuto || bottomIsAuto) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For a replaced element we use the intrinsic size
mComputedHeight = NS_INTRINSICSIZE;
} else {
// The height is based on the content
mComputedHeight = NS_AUTOHEIGHT;
}
if (topIsAuto) {
mComputedOffsets.top = NS_AUTOOFFSET; // solve for 'top'
} else {
mComputedOffsets.bottom = NS_AUTOOFFSET; // solve for 'bottom'
}
} else {
// Only 'height' is 'auto' so just solve for 'height'
mComputedHeight = containingBlockHeight - mComputedOffsets.top -
mComputedMargin.top - mComputedBorderPadding.top -
mComputedBorderPadding.bottom -
mComputedMargin.bottom - mComputedOffsets.bottom;
// Factor in any minimum and maximum size information
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
}
} else {
// Either 'top' or 'bottom' or both is 'auto'
if (topIsAuto && bottomIsAuto) {
// Treat 'top' like 'static-position'
mComputedOffsets.top = hypotheticalBox.mTop;
topIsAuto = PR_FALSE;
}
if (topIsAuto) {
// Solve for 'top'
mComputedOffsets.top = containingBlockHeight - mComputedMargin.top -
mComputedBorderPadding.top - mComputedHeight - mComputedBorderPadding.bottom -
mComputedMargin.bottom - mComputedOffsets.bottom;
} else if (bottomIsAuto) {
// Solve for 'bottom'
mComputedOffsets.bottom = containingBlockHeight - mComputedOffsets.top -
mComputedMargin.top - mComputedBorderPadding.top - mComputedHeight -
mComputedBorderPadding.bottom - mComputedMargin.bottom;
}
}
}
}
static PRBool
IsInitialContainingBlock(nsIFrame* aFrame)
{
nsIContent* content;
PRBool result = PR_FALSE;
aFrame->GetContent(&content);
if (content) {
nsIContent* parentContent;
content->GetParent(parentContent);
if (!parentContent) {
// The containing block corresponds to the document element so it's
// the initial containing block
result = PR_TRUE;
}
NS_IF_RELEASE(parentContent);
}
NS_IF_RELEASE(content);
return result;
}
nscoord
GetVerticalMarginBorderPadding(const nsHTMLReflowState* aReflowState)
{
nscoord result = 0;
if (!aReflowState) return result;
// zero auto margins
nsMargin margin = aReflowState->mComputedMargin;
if (NS_AUTOMARGIN == margin.top)
margin.top = 0;
if (NS_AUTOMARGIN == margin.bottom)
margin.bottom = 0;
result += margin.top + margin.bottom;
result += aReflowState->mComputedBorderPadding.top +
aReflowState->mComputedBorderPadding.bottom;
return result;
}
/* Get the height based on the viewport of the containing block specified
* in aReflowState when the containing block has mComputedHeight == NS_AUTOHEIGHT
* and it is the body.
*/
nscoord
CalcQuirkContainingBlockHeight(const nsHTMLReflowState& aReflowState)
{
nsHTMLReflowState* firstBlockRS = nsnull; // a candidate for body frame
nsHTMLReflowState* firstAreaRS = nsnull; // a candidate for html frame
nscoord result = 0;
const nsHTMLReflowState* rs = &aReflowState;
for (; rs; rs = (nsHTMLReflowState *)(rs->parentReflowState)) {
nsCOMPtr<nsIAtom> frameType;
rs->frame->GetFrameType(getter_AddRefs(frameType));
// if the ancestor is auto height then skip it and continue up if it
// is the first block/area frame and possibly the body/html
if (nsLayoutAtoms::blockFrame == frameType.get()) {
if (!firstBlockRS) {
firstBlockRS = (nsHTMLReflowState*)rs;
if (NS_AUTOHEIGHT == rs->mComputedHeight) continue;
}
else break;
}
else if (nsLayoutAtoms::areaFrame == frameType.get()) {
if (!firstAreaRS) {
firstAreaRS = (nsHTMLReflowState*)rs;
if (NS_AUTOHEIGHT == rs->mComputedHeight) continue;
}
else break;
}
else if (nsLayoutAtoms::canvasFrame == frameType.get()) {
// Use scroll frames' computed height if we have one, this will
// allow us to get viewport height for native scrollbars.
nsHTMLReflowState* scrollState = (nsHTMLReflowState *)rs->parentReflowState;
nsCOMPtr<nsIAtom> scrollFrameType;
scrollState->frame->GetFrameType(getter_AddRefs(scrollFrameType));
if (nsLayoutAtoms::scrollFrame == scrollFrameType.get()) {
rs = scrollState;
}
}
else {
break;
}
// if the ancestor has a computed height, it is the percent base
result = rs->mComputedHeight;
// if unconstrained - don't sutract borders - would result in huge height
if (NS_AUTOHEIGHT == result) return result;
// if we got to the canvas frame, then subtract out
// margin/border/padding for the BODY and HTML elements
if (nsLayoutAtoms::canvasFrame == frameType.get()) {
result -= GetVerticalMarginBorderPadding(firstBlockRS);
result -= GetVerticalMarginBorderPadding(firstAreaRS);
}
// if we got to the html frame, then subtract out
// margin/border/padding for the BODY element
else if (nsLayoutAtoms::areaFrame == frameType.get()) {
// make sure it is the body
nsCOMPtr<nsIAtom> fType;
rs->parentReflowState->frame->GetFrameType(getter_AddRefs(fType));
if (nsLayoutAtoms::canvasFrame == fType.get()) {
result -= GetVerticalMarginBorderPadding(firstBlockRS);
}
}
break;
}
return result;
}
// Called by InitConstraints() to compute the containing block rectangle for
// the element. Handles the special logic for absolutely positioned elements
void
nsHTMLReflowState::ComputeContainingBlockRectangle(nsIPresContext* aPresContext,
const nsHTMLReflowState* aContainingBlockRS,
nscoord& aContainingBlockWidth,
nscoord& aContainingBlockHeight)
{
// Unless the element is absolutely positioned, the containing block is
// formed by the content edge of the nearest block-level ancestor
aContainingBlockWidth = aContainingBlockRS->mComputedWidth;
aContainingBlockHeight = aContainingBlockRS->mComputedHeight;
if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE) {
// See if the ancestor is block-level or inline-level
if (NS_FRAME_GET_TYPE(aContainingBlockRS->mFrameType) == NS_CSS_FRAME_TYPE_INLINE) {
// The CSS2 spec says that if the ancestor is inline-level, the containing
// block depends on the 'direction' property of the ancestor. For direction
// 'ltr', it's the top and left of the content edges of the first box and
// the bottom and right content edges of the last box
//
// XXX This is a pain because it isn't top-down and it requires that we've
// completely reflowed the ancestor. It also isn't clear what happens when
// a relatively positioned ancestor is split across pages. So instead use
// the computed width and height of the nearest block-level ancestor
const nsHTMLReflowState* cbrs = aContainingBlockRS;
while (cbrs) {
nsCSSFrameType type = NS_FRAME_GET_TYPE(cbrs->mFrameType);
if ((NS_CSS_FRAME_TYPE_BLOCK == type) ||
(NS_CSS_FRAME_TYPE_FLOATING == type) ||
(NS_CSS_FRAME_TYPE_ABSOLUTE == type)) {
aContainingBlockWidth = cbrs->mComputedWidth;
aContainingBlockHeight = cbrs->mComputedHeight;
if (NS_CSS_FRAME_TYPE_ABSOLUTE == type) {
aContainingBlockWidth += cbrs->mComputedPadding.left +
cbrs->mComputedPadding.right;
aContainingBlockHeight += cbrs->mComputedPadding.top +
cbrs->mComputedPadding.bottom;
}
break;
}
cbrs = (const nsHTMLReflowState*)cbrs->parentReflowState; // XXX cast
}
} else {
// If the ancestor is block-level, the containing block is formed by the
// padding edge of the ancestor
aContainingBlockWidth += aContainingBlockRS->mComputedPadding.left +
aContainingBlockRS->mComputedPadding.right;
// If the containing block is the initial containing block and it has a
// height that depends on its content, then use the viewport height instead.
// This gives us a reasonable value against which to compute percentage
// based heights and to do bottom relative positioning
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
IsInitialContainingBlock(aContainingBlockRS->frame)) {
// Use the viewport height as the containing block height
const nsHTMLReflowState* rs = aContainingBlockRS->parentReflowState;
while (rs) {
aContainingBlockHeight = rs->mComputedHeight;
rs = rs->parentReflowState;
}
} else {
aContainingBlockHeight += aContainingBlockRS->mComputedPadding.top +
aContainingBlockRS->mComputedPadding.bottom;
}
}
} else {
// If this is an unconstrained reflow, then reset the containing block
// width to NS_UNCONSTRAINEDSIZE. This way percentage based values have
// no effect
if (NS_UNCONSTRAINEDSIZE == availableWidth) {
aContainingBlockWidth = NS_UNCONSTRAINEDSIZE;
}
// an element in quirks mode gets a containing block based on the viewport (less
// body margins, border, padding) if the element is a child of the body.
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
nsCompatibility mode;
aPresContext->GetCompatibilityMode(&mode);
if (eCompatibility_NavQuirks == mode) {
aContainingBlockHeight = CalcQuirkContainingBlockHeight(*aContainingBlockRS);
}
}
}
}
// XXX refactor this code to have methods for each set of properties
// we are computing: width,height,line-height; margin; offsets
void
nsHTMLReflowState::InitConstraints(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
// If this is the root frame, then set the computed width and
// height equal to the available space
if (nsnull == parentReflowState) {
mComputedWidth = availableWidth;
mComputedHeight = availableHeight;
mComputedMargin.SizeTo(0, 0, 0, 0);
mComputedPadding.SizeTo(0, 0, 0, 0);
mComputedBorderPadding.SizeTo(0, 0, 0, 0);
mComputedOffsets.SizeTo(0, 0, 0, 0);
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
// Get the containing block reflow state
const nsHTMLReflowState* cbrs =
GetContainingBlockReflowState(parentReflowState);
NS_ASSERTION(nsnull != cbrs, "no containing block");
// If we weren't given a containing block width and height, then
// compute one
if (aContainingBlockWidth == -1) {
ComputeContainingBlockRectangle(aPresContext, cbrs, aContainingBlockWidth,
aContainingBlockHeight);
}
// See if the element is relatively positioned
if (NS_STYLE_POSITION_RELATIVE == mStylePosition->mPosition) {
ComputeRelativeOffsets(cbrs, aContainingBlockWidth, aContainingBlockHeight);
} else {
// Initialize offsets to 0
mComputedOffsets.SizeTo(0, 0, 0, 0);
}
#if 0
nsFrame::ListTag(stdout, frame); printf(": cb=");
nsFrame::ListTag(stdout, cbrs->frame); printf(" size=%d,%d\n", aContainingBlockWidth, aContainingBlockHeight);
#endif
// See if the containing block height is based on the size of its
// content
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
// See if the containing block is a scrolled frame, i.e. its
// parent is a scroll frame. The presence of the intervening
// frame (that the scroll frame scrolls) needs to be hidden from
// the containingBlockHeight calcuation.
if (cbrs->parentReflowState) {
nsIFrame* f = cbrs->parentReflowState->frame;
nsCOMPtr<nsIAtom> fType;
f->GetFrameType(getter_AddRefs(fType));
if (nsLayoutAtoms::scrollFrame == fType.get()) {
// Use the scroll frame's computed height instead
aContainingBlockHeight =
((nsHTMLReflowState*)cbrs->parentReflowState)->mComputedHeight;
}
}
}
// Compute margins from the specified margin style information. These
// become the default computed values, and may be adjusted below
// XXX fix to provide 0,0 for the top&bottom margins for
// inline-non-replaced elements
ComputeMargin(aContainingBlockWidth, cbrs);
ComputePadding(aContainingBlockWidth, cbrs);
if (!mStyleSpacing->GetBorder(mComputedBorderPadding)) {
// CSS2 has no percentage borders
mComputedBorderPadding.SizeTo(0, 0, 0, 0);
}
mComputedBorderPadding += mComputedPadding;
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
nsStyleUnit heightUnit = mStylePosition->mHeight.GetUnit();
nsCOMPtr<nsIAtom> frameType;
frame->GetFrameType(getter_AddRefs(frameType));
// Check for a percentage based width and an unconstrained containing
// block width
if (eStyleUnit_Percent == widthUnit) {
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
widthUnit = eStyleUnit_Auto;
}
}
// Check for a percentage based height and a containing block height
// that depends on the content height
if (eStyleUnit_Percent == heightUnit) {
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
// this if clause enables %-height on replaced inline frames,
// such as images. See bug 54119. The else clause "heightUnit = eStyleUnit_Auto;"
// used to be called exclusively.
if (NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_INLINE) == mFrameType) {
// Get the containing block reflow state
const nsHTMLReflowState* cbrs =
GetContainingBlockReflowState(parentReflowState);
NS_ASSERTION(nsnull != cbrs, "no containing block");
nsCompatibility mode;
aPresContext->GetCompatibilityMode(&mode);
// in quirks mode, get the cb height using the special quirk method
if (eCompatibility_NavQuirks == mode) {
aContainingBlockHeight = CalcQuirkContainingBlockHeight(*cbrs);
}
// in standard mode, use the cb height. if it's "auto", as will be the case
// by default in BODY, use auto height as per CSS2 spec.
else
{
if (NS_AUTOHEIGHT != cbrs->mComputedHeight)
aContainingBlockHeight = cbrs->mComputedHeight;
else
heightUnit = eStyleUnit_Auto;
}
}
else {
// default to interpreting the height like 'auto'
heightUnit = eStyleUnit_Auto;
}
}
}
// Calculate the computed values for min and max properties
ComputeMinMaxValues(aContainingBlockWidth, aContainingBlockHeight, cbrs);
// Calculate the computed width and height. This varies by frame type
if ((NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_INLINE) == mFrameType) ||
(NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_FLOATING) == mFrameType)) {
// Inline replaced element and floating replaced element are basically
// treated the same. First calculate the computed width
if (eStyleUnit_Inherit == widthUnit) {
mComputedWidth = aContainingBlockWidth;
} else if (eStyleUnit_Auto == widthUnit) {
// A specified value of 'auto' uses the element's intrinsic width
mComputedWidth = NS_INTRINSICSIZE;
} else {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth,
mComputedWidth);
}
if (mComputedWidth != NS_INTRINSICSIZE) {
// Take into account minimum and maximum sizes
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
// See what edge the width applies to (the default is the content
// edge)
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedWidth -= mComputedPadding.left + mComputedPadding.right;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedWidth -= mComputedBorderPadding.left + mComputedBorderPadding.right;
}
}
// Now calculate the computed height
if (eStyleUnit_Inherit == heightUnit) {
mComputedHeight = aContainingBlockHeight;
} else if (eStyleUnit_Auto == heightUnit) {
// A specified value of 'auto' uses the element's intrinsic height
mComputedHeight = NS_INTRINSICSIZE;
} else {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
mStylePosition->mHeight,
mComputedHeight);
}
if (mComputedHeight != NS_INTRINSICSIZE) {
// Take into account minimum and maximum sizes
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
// See what edge the height applies to (the default is the content
// edge)
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedHeight -= mComputedPadding.top + mComputedPadding.bottom;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedHeight -= mComputedBorderPadding.top + mComputedBorderPadding.bottom;
}
}
} else if (NS_CSS_FRAME_TYPE_FLOATING == mFrameType) {
// Floating non-replaced element. First calculate the computed width
if (eStyleUnit_Inherit == widthUnit) {
mComputedWidth = aContainingBlockWidth;
} else if (eStyleUnit_Auto == widthUnit) {
if ((NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) &&
(eStyleUnit_Percent == mStylePosition->mWidth.GetUnit())) {
// The element has a percentage width, but since the containing
// block width is unconstrained we set 'widthUnit' to 'auto'
// above. However, we want the element to be unconstrained, too
mComputedWidth = NS_UNCONSTRAINEDSIZE;
} else if (NS_STYLE_DISPLAY_TABLE == mStyleDisplay->mDisplay) {
// It's an outer table because an inner table is not positioned
// shrink wrap its width since the outer table is anonymous
mComputedWidth = NS_SHRINKWRAPWIDTH;
} else {
// The CSS2 spec says the computed width should be 0; however, that's
// not what Nav and IE do and even the spec doesn't really want that
// to happen.
//
// Instead, have the element shrink wrap its width
mComputedWidth = NS_SHRINKWRAPWIDTH;
// Limnit the width to the containing block width
if (mComputedMaxWidth > aContainingBlockWidth) {
mComputedMaxWidth = aContainingBlockWidth;
}
}
} else {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth,
mComputedWidth);
}
// Take into account minimum and maximum sizes
if (mComputedWidth != NS_SHRINKWRAPWIDTH) {
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
// See what edge the width applies to (the default is the content
// edge)
if (mComputedWidth > 0) {
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedWidth -= mComputedPadding.left + mComputedPadding.right;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedWidth -= mComputedBorderPadding.left + mComputedBorderPadding.right;
}
}
}
// Now calculate the computed height
if (eStyleUnit_Inherit == heightUnit) {
mComputedHeight = aContainingBlockHeight;
} else if (eStyleUnit_Auto == heightUnit) {
mComputedHeight = NS_AUTOHEIGHT; // let it choose its height
} else {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
mStylePosition->mHeight,
mComputedHeight);
}
// Take into account minimum and maximum sizes
if (mComputedHeight != NS_AUTOHEIGHT) {
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
// See what edge the height applies to (the default is the content
// edge)
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedHeight -= mComputedPadding.top + mComputedPadding.bottom;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedHeight -= mComputedBorderPadding.top + mComputedBorderPadding.bottom;
}
}
} else if (NS_CSS_FRAME_TYPE_INTERNAL_TABLE == mFrameType) {
// Internal table elements. The rules vary depending on the type.
// Calculate the computed width
PRBool rowOrRowGroup = PR_FALSE;
if ((NS_STYLE_DISPLAY_TABLE_ROW == mStyleDisplay->mDisplay) ||
(NS_STYLE_DISPLAY_TABLE_ROW_GROUP == mStyleDisplay->mDisplay)) {
// 'width' property doesn't apply to table rows and row groups
widthUnit = eStyleUnit_Auto;
rowOrRowGroup = PR_TRUE;
}
if (eStyleUnit_Inherit == widthUnit) {
mComputedWidth = aContainingBlockWidth;
} else if (eStyleUnit_Auto == widthUnit) {
mComputedWidth = availableWidth;
if ((mComputedWidth != NS_UNCONSTRAINEDSIZE) && !rowOrRowGroup){
// Internal table elements don't have margins. Only tables and
// cells have border and padding
mComputedWidth -= mComputedBorderPadding.left +
mComputedBorderPadding.right;
}
} else {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth,
mComputedWidth);
}
// Calculate the computed height
if ((NS_STYLE_DISPLAY_TABLE_COLUMN == mStyleDisplay->mDisplay) ||
(NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP == mStyleDisplay->mDisplay)) {
// 'height' property doesn't apply to table columns and column groups
heightUnit = eStyleUnit_Auto;
}
if (eStyleUnit_Inherit == heightUnit) {
mComputedHeight = aContainingBlockHeight;
} else if (eStyleUnit_Auto == heightUnit) {
mComputedHeight = NS_AUTOHEIGHT;
} else {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
mStylePosition->mHeight,
mComputedHeight);
}
// Doesn't apply to table elements
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE) {
// XXX not sure if this belongs here or somewhere else - cwk
// an nsHTMLFrameInnerFrame doesn't get a placeholder frame, the nsHTMLFrameOuterFrame does
nsIAtom* targetFrameType;
frame->GetFrameType(&targetFrameType);
if (nsLayoutAtoms::htmlFrameInnerFrame != targetFrameType) {
InitAbsoluteConstraints(aPresContext, cbrs, aContainingBlockWidth,
aContainingBlockHeight);
}
NS_IF_RELEASE(targetFrameType);
} else if (NS_CSS_FRAME_TYPE_INLINE == mFrameType) {
// Inline non-replaced elements do not have computed widths or heights
// XXX add this check to HaveFixedContentHeight/Width too
mComputedWidth = NS_UNCONSTRAINEDSIZE;
mComputedHeight = NS_UNCONSTRAINEDSIZE;
mComputedMargin.top = 0;
mComputedMargin.bottom = 0;
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
ComputeBlockBoxData(aPresContext, cbrs, widthUnit, heightUnit,
aContainingBlockWidth,
aContainingBlockHeight);
}
}
}
// Compute the box data for block and block-replaced elements in the
// normal flow.
void
nsHTMLReflowState::ComputeBlockBoxData(nsIPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nsStyleUnit aWidthUnit,
nsStyleUnit aHeightUnit,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
// Compute the content width
if (eStyleUnit_Auto == aWidthUnit) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// Block-level replaced element in the flow. A specified value of
// 'auto' uses the element's intrinsic width (CSS2 10.3.4)
mComputedWidth = NS_INTRINSICSIZE;
} else {
// Block-level non-replaced element in the flow. 'auto' values
// for margin-left and margin-right become 0, and the sum of the
// areas must equal the width of the content-area of the parent
// element.
if (NS_UNCONSTRAINEDSIZE == availableWidth) {
// During pass1 table reflow, auto side margin values are
// uncomputable (== 0).
mComputedWidth = NS_UNCONSTRAINEDSIZE;
} else if (NS_SHRINKWRAPWIDTH == aContainingBlockWidth) {
// The containing block should shrink wrap its width, so have
// the child block do the same
mComputedWidth = NS_UNCONSTRAINEDSIZE;
// Let its content area be as wide as the containing block's max width
// minus any margin and border/padding
nscoord maxWidth = cbrs->mComputedMaxWidth - mComputedMargin.left -
mComputedBorderPadding.left - mComputedMargin.right -
mComputedBorderPadding.right;
if (maxWidth < mComputedMaxWidth) {
mComputedMaxWidth = maxWidth;
}
} else {
// tables act like replaced elements regarding mComputedWidth
nsCOMPtr<nsIAtom> fType;
frame->GetFrameType(getter_AddRefs(fType));
if (nsLayoutAtoms::tableOuterFrame == fType.get()) {
mComputedWidth = 0; // XXX temp fix for trees
} else if (nsLayoutAtoms::tableFrame == fType.get()) {
mComputedWidth = NS_SHRINKWRAPWIDTH;
if (eStyleUnit_Auto == mStyleSpacing->mMargin.GetLeftUnit()) {
mComputedMargin.left = NS_AUTOMARGIN;
}
if (eStyleUnit_Auto == mStyleSpacing->mMargin.GetRightUnit()) {
mComputedMargin.right = NS_AUTOMARGIN;
}
} else {
mComputedWidth = availableWidth - mComputedMargin.left -
mComputedMargin.right - mComputedBorderPadding.left -
mComputedBorderPadding.right;
}
// Take into account any min and max values
if (mComputedWidth > mComputedMaxWidth) {
// Use 'max-width' as the value for 'width'
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
// Use 'min-width' as the value for 'width'
mComputedWidth = mComputedMinWidth;
}
}
}
} else {
if (eStyleUnit_Inherit == aWidthUnit) {
// Use parent element's width. Note that if its width was
// 'inherit', then it already did this so we don't need to
// recurse upwards.
//
// We use the containing block's width here for the "parent"
// elements width, because we want to skip over any intervening
// inline elements (since width doesn't apply to them).
if (NS_UNCONSTRAINEDSIZE != aContainingBlockWidth) {
mComputedWidth = aContainingBlockWidth;
}
else {
mComputedWidth = NS_UNCONSTRAINEDSIZE;
}
}
else {
ComputeHorizontalValue(aContainingBlockWidth, aWidthUnit,
mStylePosition->mWidth, mComputedWidth);
}
// Take into account any min and max values
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
// See what edge the width applies to (the default is the content
// edge)
if (mComputedWidth != NS_UNCONSTRAINEDSIZE) {
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedWidth -= mComputedPadding.left + mComputedPadding.right;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedWidth -= mComputedBorderPadding.left + mComputedBorderPadding.right;
}
}
// Now that we have the computed-width, compute the side margins
CalculateBlockSideMargins(cbrs->mComputedWidth, mComputedWidth);
}
// Compute the content height
if (eStyleUnit_Inherit == aHeightUnit) {
// Use parent elements height (note that if its height was inherit
// then it already did this so we don't need to recurse upwards).
//
// We use the containing blocks height here for the "parent"
// elements height because we want to skip over any interveening
// inline elements (since height doesn't apply to them).
if (NS_UNCONSTRAINEDSIZE != aContainingBlockHeight) {
mComputedHeight = aContainingBlockHeight;
}
else {
mComputedHeight = NS_UNCONSTRAINEDSIZE;
}
} else if (eStyleUnit_Auto == aHeightUnit) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For replaced elements use the intrinsic size for "auto"
mComputedHeight = NS_INTRINSICSIZE;
} else {
// For non-replaced elements auto means unconstrained
mComputedHeight = NS_UNCONSTRAINEDSIZE;
}
} else {
ComputeVerticalValue(aContainingBlockHeight, aHeightUnit,
mStylePosition->mHeight, mComputedHeight);
}
// Take into account any min and max values
if (mComputedHeight != NS_AUTOHEIGHT) {
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
}
// See what edge the height applies to (the default is the content
// edge)
if (mComputedHeight != NS_UNCONSTRAINEDSIZE) {
if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_PADDING) {
mComputedHeight -= mComputedPadding.top + mComputedPadding.bottom;
} else if (mStylePosition->mBoxSizing == NS_STYLE_BOX_SIZING_BORDER) {
mComputedHeight -= mComputedBorderPadding.top + mComputedBorderPadding.bottom;
}
}
}
// This code enforces section 10.3.3 of the CSS2 spec for this formula:
//
// 'margin-left' + 'border-left-width' + 'padding-left' + 'width' +
// 'padding-right' + 'border-right-width' + 'margin-right'
// = width of containing block
//
// Note: the width unit is not auto when this is called
void
nsHTMLReflowState::CalculateBlockSideMargins(nscoord aAvailWidth,
nscoord aComputedWidth)
{
// We can only provide values for auto side margins in a constrained
// reflow. For unconstrained reflow there is no effective width to
// compute against...
if ((NS_UNCONSTRAINEDSIZE == aComputedWidth) ||
(NS_UNCONSTRAINEDSIZE == aAvailWidth)) {
return;
}
nscoord sum = mComputedMargin.left + mComputedBorderPadding.left +
aComputedWidth + mComputedBorderPadding.right + mComputedMargin.right;
if (sum == aAvailWidth) {
// The sum is already correct
return;
}
// Determine the left and right margin values. The width value
// remains constant while we do this.
PRBool isAutoLeftMargin =
eStyleUnit_Auto == mStyleSpacing->mMargin.GetLeftUnit();
PRBool isAutoRightMargin =
eStyleUnit_Auto == mStyleSpacing->mMargin.GetRightUnit();
// Calculate how much space is available for margins
nscoord availMarginSpace = aAvailWidth - aComputedWidth -
mComputedBorderPadding.left - mComputedBorderPadding.right;
if (mStyleDisplay->mDisplay == NS_STYLE_DISPLAY_TABLE) {
// Special rules for tables. In general, tables will stick to the
// left edge when they are too large otherwise they behave like
// blocks.
if (availMarginSpace < 0) {
// Whoops - the TABLE element is too large for the available
// space. In this case use the "direction" property to pin the
// element to the left or right side. Note that we look at the
// parent's direction since the parent will be placing this
// element.
mComputedMargin.left = 0;
mComputedMargin.right = 0;
const nsHTMLReflowState* prs = (const nsHTMLReflowState*)
parentReflowState;
if (prs && (NS_STYLE_DIRECTION_RTL == prs->mStyleDisplay->mDirection)) {
mComputedMargin.left = availMarginSpace;
}
isAutoLeftMargin = isAutoRightMargin = PR_FALSE;
}
}
else {
// The css2 spec clearly defines how block elements should be have
// in section 10.3.3.
if (!isAutoLeftMargin && !isAutoRightMargin) {
// Neither margin is 'auto' so we're over constrained. Use the
// 'direction' property of the parent to tell which margin to
// ignore
const nsHTMLReflowState* prs = (const nsHTMLReflowState*)
parentReflowState;
if (prs) {
// First check if there is an HTML alignment that we should honor
if ((prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER) ||
(prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_RIGHT))
{
isAutoLeftMargin = PR_TRUE;
isAutoRightMargin =
(prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER);
} else
// Otherwise apply the CSS rules
if (NS_STYLE_DIRECTION_LTR == prs->mStyleDisplay->mDirection) {
// The specified value of margin-right is ignored (== forced
// to auto)
isAutoRightMargin = PR_TRUE;
}
else {
isAutoLeftMargin = PR_TRUE;
}
}
else {
// No parent reflow state -- assume direction is ltr
isAutoRightMargin = PR_TRUE;
}
}
}
// Logic which is common to blocks and tables
if (isAutoLeftMargin) {
if (isAutoRightMargin) {
// Both margins are 'auto' so their computed values are equal
mComputedMargin.left = availMarginSpace / 2;
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
} else {
mComputedMargin.left = availMarginSpace - mComputedMargin.right;
}
} else if (isAutoRightMargin) {
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
}
}
PRBool
nsHTMLReflowState::UseComputedHeight()
{
static PRBool useComputedHeight = PR_FALSE;
#if defined(XP_UNIX) || defined(XP_PC) || defined(XP_BEOS)
static PRBool firstTime = 1;
if (firstTime) {
if (getenv("GECKO_USE_COMPUTED_HEIGHT")) {
useComputedHeight = PR_TRUE;
}
firstTime = 0;
}
#endif
return useComputedHeight;
}
static nsIStyleContext*
GetNonInheritedLineHeightStyleContext(nsIStyleContext* aStyleContext)
{
nsIStyleContext* parentSC;
parentSC = aStyleContext->GetParent();
if (parentSC) {
const nsStyleText* text = (const nsStyleText*)
parentSC->GetStyleData(eStyleStruct_Text);
if (eStyleUnit_Inherit == text->mLineHeight.GetUnit()) {
nsIStyleContext* sc = GetNonInheritedLineHeightStyleContext(parentSC);
NS_RELEASE(parentSC);
return sc;
}
}
return parentSC;
}
static nscoord
ComputeLineHeight(nsIRenderingContext* aRenderingContext,
nsIStyleContext* aStyleContext)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
nscoord lineHeight = -1;
const nsStyleText* text = (const nsStyleText*)
aStyleContext->GetStyleData(eStyleStruct_Text);
const nsStyleFont* font = (const nsStyleFont*)
aStyleContext->GetStyleData(eStyleStruct_Font);
const nsStyleDisplay* display = (const nsStyleDisplay*)
aStyleContext->GetStyleData(eStyleStruct_Display);
nsStyleUnit unit = text->mLineHeight.GetUnit();
if (eStyleUnit_Inherit == unit) {
// Inherit parents line-height value
nsCOMPtr<nsIStyleContext> parentSC =
getter_AddRefs(GetNonInheritedLineHeightStyleContext(aStyleContext));
if (parentSC) {
text = (const nsStyleText*) parentSC->GetStyleData(eStyleStruct_Text);
unit = text->mLineHeight.GetUnit();
if (eStyleUnit_Percent == unit) {
// For percent, we inherit the computed value so update the
// font to use the parent's font not our font.
font = (const nsStyleFont*) parentSC->GetStyleData(eStyleStruct_Font);
}
}
}
if (eStyleUnit_Coord == unit) {
// For length values just use the pre-computed value
lineHeight = text->mLineHeight.GetCoordValue();
}
else {
// For "normal", factor or percentage units the computed value of
// the line-height property is found by multiplying the factor by
// the font's <b>actual</b> em height. For "normal" we use the
// font's normal line height (em height + leading).
nscoord emHeight = -1;
nscoord normalLineHeight = -1;
nsCOMPtr<nsIDeviceContext> deviceContext;
aRenderingContext->GetDeviceContext(*getter_AddRefs(deviceContext));
nsCOMPtr<nsIAtom> langGroup;
if (display->mLanguage) {
display->mLanguage->GetLanguageGroup(getter_AddRefs(langGroup));
}
nsCOMPtr<nsIFontMetrics> fm;
deviceContext->GetMetricsFor(font->mFont, langGroup, *getter_AddRefs(fm));
#ifdef NEW_FONT_HEIGHT_APIS
if (fm) {
fm->GetEmHeight(emHeight);
fm->GetNormalLineHeight(normalLineHeight);
}
#endif
float factor;
if (eStyleUnit_Factor == unit) {
factor = text->mLineHeight.GetFactorValue();
}
else if (eStyleUnit_Percent == unit) {
factor = text->mLineHeight.GetPercentValue();
}
else {
factor = (((float) normalLineHeight) / PR_MAX(1, emHeight));
}
// Note: we normally use the actual font height for computing the
// line-height raw value from the style context. On systems where
// they disagree the actual font height is more appropriate. This
// little hack lets us override that behavior to allow for more
// precise layout in the face of imprecise fonts.
if (nsHTMLReflowState::UseComputedHeight()) {
emHeight = font->mFont.size;
}
lineHeight = NSToCoordRound(factor * emHeight);
}
return lineHeight;
}
nscoord
nsHTMLReflowState::CalcLineHeight(nsIPresContext* aPresContext,
nsIRenderingContext* aRenderingContext,
nsIFrame* aFrame)
{
nscoord lineHeight = -1;
nsCOMPtr<nsIStyleContext> sc;
aFrame->GetStyleContext(getter_AddRefs(sc));
if (sc) {
lineHeight = ComputeLineHeight(aRenderingContext, sc);
}
if (lineHeight < 0) {
// Negative line-heights are not allowed by the spec. Translate
// them into "normal" when found.
const nsStyleFont* font = (const nsStyleFont*)
sc->GetStyleData(eStyleStruct_Font);
if (UseComputedHeight()) {
lineHeight = font->mFont.size;
}
else {
aRenderingContext->SetFont(font->mFont);
nsCOMPtr<nsIFontMetrics> fm;
aRenderingContext->GetFontMetrics(*getter_AddRefs(fm));
#ifdef NEW_FONT_HEIGHT_APIS
if (fm) {
fm->GetNormalLineHeight(lineHeight);
}
#endif
}
}
return lineHeight;
}
void
nsHTMLReflowState::ComputeHorizontalValue(nscoord aContainingBlockWidth,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
NS_PRECONDITION(eStyleUnit_Inherit != aUnit, "unexpected unit");
aResult = 0;
if (eStyleUnit_Percent == aUnit) {
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
aResult = 0;
} else {
float pct = aCoord.GetPercentValue();
aResult = NSToCoordFloor(aContainingBlockWidth * pct);
}
} else if (eStyleUnit_Coord == aUnit) {
aResult = aCoord.GetCoordValue();
}
else if (eStyleUnit_Chars == aUnit) {
if ((nsnull == rendContext) || (nsnull == frame)) {
// We can't compute it without a rendering context or frame, so
// pretend its zero...
}
else {
const nsStyleFont* font;
frame->GetStyleData(eStyleStruct_Font, (const nsStyleStruct*&) font);
rendContext->SetFont(font->mFont);
nscoord fontWidth;
rendContext->GetWidth('M', fontWidth);
aResult = aCoord.GetIntValue() * fontWidth;
}
}
}
void
nsHTMLReflowState::ComputeVerticalValue(nscoord aContainingBlockHeight,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
NS_PRECONDITION(eStyleUnit_Inherit != aUnit, "unexpected unit");
aResult = 0;
if (eStyleUnit_Percent == aUnit) {
// Verify no one is trying to calculate a percentage based height against
// a height that's shrink wrapping to its content. In that case they should
// treat the specified value like 'auto'
NS_ASSERTION(NS_AUTOHEIGHT != aContainingBlockHeight, "unexpected containing block height");
if (NS_AUTOHEIGHT!=aContainingBlockHeight)
{
float pct = aCoord.GetPercentValue();
aResult = NSToCoordFloor(aContainingBlockHeight * pct);
}
else { // safest thing to do for an undefined height is to make it 0
aResult = 0;
}
} else if (eStyleUnit_Coord == aUnit) {
aResult = aCoord.GetCoordValue();
}
}
void
nsHTMLReflowState::ComputeMargin(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS)
{
// If style style can provide us the margin directly, then use it.
if (!mStyleSpacing->GetMargin(mComputedMargin)) {
// We have to compute the value
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
mComputedMargin.left = 0;
mComputedMargin.right = 0;
if (eStyleUnit_Coord == mStyleSpacing->mMargin.GetLeftUnit()) {
nsStyleCoord left;
mStyleSpacing->mMargin.GetLeft(left),
mComputedMargin.left = left.GetCoordValue();
}
if (eStyleUnit_Coord == mStyleSpacing->mMargin.GetRightUnit()) {
nsStyleCoord right;
mStyleSpacing->mMargin.GetRight(right),
mComputedMargin.right = right.GetCoordValue();
}
} else {
nsStyleCoord left, right;
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetLeftUnit()) {
mComputedMargin.left = aContainingBlockRS->mComputedMargin.left;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetLeftUnit(),
mStyleSpacing->mMargin.GetLeft(left),
mComputedMargin.left);
}
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetRightUnit()) {
mComputedMargin.right = aContainingBlockRS->mComputedMargin.right;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetRightUnit(),
mStyleSpacing->mMargin.GetRight(right),
mComputedMargin.right);
}
}
const nsHTMLReflowState* rs2 = GetPageBoxReflowState(parentReflowState);
nsStyleCoord top, bottom;
if (nsnull != rs2) {
// According to the CSS2 spec, margin percentages are
// calculated with respect to the *height* of the containing
// block when in a paginated context.
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetTopUnit()) {
mComputedMargin.top = aContainingBlockRS->mComputedMargin.top;
} else {
ComputeVerticalValue(rs2->mComputedHeight,
mStyleSpacing->mMargin.GetTopUnit(),
mStyleSpacing->mMargin.GetTop(top),
mComputedMargin.top);
}
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetBottomUnit()) {
mComputedMargin.bottom = aContainingBlockRS->mComputedMargin.bottom;
} else {
ComputeVerticalValue(rs2->mComputedHeight,
mStyleSpacing->mMargin.GetBottomUnit(),
mStyleSpacing->mMargin.GetBottom(bottom),
mComputedMargin.bottom);
}
}
else {
// According to the CSS2 spec, margin percentages are
// calculated with respect to the *width* of the containing
// block, even for margin-top and margin-bottom.
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
mComputedMargin.top = 0;
mComputedMargin.bottom = 0;
} else {
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetTopUnit()) {
mComputedMargin.top = aContainingBlockRS->mComputedMargin.top;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetTopUnit(),
mStyleSpacing->mMargin.GetTop(top),
mComputedMargin.top);
}
if (eStyleUnit_Inherit == mStyleSpacing->mMargin.GetBottomUnit()) {
mComputedMargin.bottom = aContainingBlockRS->mComputedMargin.bottom;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mMargin.GetBottomUnit(),
mStyleSpacing->mMargin.GetBottom(bottom),
mComputedMargin.bottom);
}
}
}
}
}
void
nsHTMLReflowState::ComputePadding(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS)
{
// If style can provide us the padding directly, then use it.
if (!mStyleSpacing->GetPadding(mComputedPadding)) {
// We have to compute the value
nsStyleCoord left, right, top, bottom;
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetLeftUnit()) {
mComputedPadding.left = aContainingBlockRS->mComputedPadding.left;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetLeftUnit(),
mStyleSpacing->mPadding.GetLeft(left),
mComputedPadding.left);
}
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetRightUnit()) {
mComputedPadding.right = aContainingBlockRS->mComputedPadding.right;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetRightUnit(),
mStyleSpacing->mPadding.GetRight(right),
mComputedPadding.right);
}
// According to the CSS2 spec, percentages are calculated with respect to
// containing block width for padding-top and padding-bottom
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetTopUnit()) {
mComputedPadding.top = aContainingBlockRS->mComputedPadding.top;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetTopUnit(),
mStyleSpacing->mPadding.GetTop(top),
mComputedPadding.top);
}
if (eStyleUnit_Inherit == mStyleSpacing->mPadding.GetBottomUnit()) {
mComputedPadding.bottom = aContainingBlockRS->mComputedPadding.bottom;
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleSpacing->mPadding.GetBottomUnit(),
mStyleSpacing->mPadding.GetBottom(bottom),
mComputedPadding.bottom);
}
}
}
void
nsHTMLReflowState::ComputeMinMaxValues(nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsHTMLReflowState* aContainingBlockRS)
{
nsStyleUnit minWidthUnit = mStylePosition->mMinWidth.GetUnit();
if (eStyleUnit_Inherit == minWidthUnit) {
mComputedMinWidth = aContainingBlockRS->mComputedMinWidth;
} else {
ComputeHorizontalValue(aContainingBlockWidth, minWidthUnit,
mStylePosition->mMinWidth, mComputedMinWidth);
}
nsStyleUnit maxWidthUnit = mStylePosition->mMaxWidth.GetUnit();
if (eStyleUnit_Inherit == maxWidthUnit) {
mComputedMaxWidth = aContainingBlockRS->mComputedMaxWidth;
} else if (eStyleUnit_Null == maxWidthUnit) {
// Specified value of 'none'
mComputedMaxWidth = NS_UNCONSTRAINEDSIZE; // no limit
} else {
ComputeHorizontalValue(aContainingBlockWidth, maxWidthUnit,
mStylePosition->mMaxWidth, mComputedMaxWidth);
}
// If the computed value of 'min-width' is greater than the value of
// 'max-width', 'max-width' is set to the value of 'min-width'
if (mComputedMinWidth > mComputedMaxWidth) {
mComputedMaxWidth = mComputedMinWidth;
}
nsStyleUnit minHeightUnit = mStylePosition->mMinHeight.GetUnit();
if (eStyleUnit_Inherit == minHeightUnit) {
mComputedMinHeight = aContainingBlockRS->mComputedMinHeight;
} else {
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
(eStyleUnit_Percent == minHeightUnit)) {
mComputedMinHeight = 0;
} else {
ComputeVerticalValue(aContainingBlockHeight, minHeightUnit,
mStylePosition->mMinHeight, mComputedMinHeight);
}
}
nsStyleUnit maxHeightUnit = mStylePosition->mMaxHeight.GetUnit();
if (eStyleUnit_Inherit == maxHeightUnit) {
mComputedMaxHeight = aContainingBlockRS->mComputedMaxHeight;
} else if (eStyleUnit_Null == maxHeightUnit) {
// Specified value of 'none'
mComputedMaxHeight = NS_UNCONSTRAINEDSIZE; // no limit
} else {
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
(eStyleUnit_Percent == maxHeightUnit)) {
mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
ComputeVerticalValue(aContainingBlockHeight, maxHeightUnit,
mStylePosition->mMaxHeight, mComputedMaxHeight);
}
}
// If the computed value of 'min-height' is greater than the value of
// 'max-height', 'max-height' is set to the value of 'min-height'
if (mComputedMinHeight > mComputedMaxHeight) {
mComputedMaxHeight = mComputedMinHeight;
}
}
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