gecko-dev/widget/ScrollbarDrawingMac.cpp
Emilio Cobos Álvarez 4b4ff83478 Bug 1689253 - Add a more sensible scrollbar size API to nsITheme, and use it to replace ScrollbarNonDisappearing. r=spohl
There's no reason we should need an scrollbar box to query the size of a
scrollbar. I plan to use this in the following patch to make the size of a
resizer not vary depending on whether the container has scrollbars or not,
which is what ultimately causes the reftest failure.

Differential Revision: https://phabricator.services.mozilla.com/D103302
2021-01-28 22:11:54 +00:00

339 lines
12 KiB
C++

/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 2; -*- */
/* vim: set sw=2 ts=8 et tw=80 : */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "ScrollbarDrawingMac.h"
#include "mozilla/gfx/Helpers.h"
#include "mozilla/gfx/PathHelpers.h"
#include "mozilla/RelativeLuminanceUtils.h"
#include "nsLayoutUtils.h"
#include "nsIFrame.h"
#include "nsLookAndFeel.h"
#include "nsContainerFrame.h"
#include "nsNativeTheme.h"
namespace mozilla {
using namespace gfx;
namespace widget {
static nsIFrame* GetParentScrollbarFrame(nsIFrame* aFrame) {
// Walk our parents to find a scrollbar frame
nsIFrame* scrollbarFrame = aFrame;
do {
if (scrollbarFrame->IsScrollbarFrame()) {
break;
}
} while ((scrollbarFrame = scrollbarFrame->GetParent()));
// We return null if we can't find a parent scrollbar frame
return scrollbarFrame;
}
static bool IsParentScrollbarRolledOver(nsIFrame* aFrame) {
nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
return nsLookAndFeel::GetInt(LookAndFeel::IntID::UseOverlayScrollbars) != 0
? nsNativeTheme::CheckBooleanAttr(scrollbarFrame, nsGkAtoms::hover)
: nsNativeTheme::GetContentState(scrollbarFrame,
StyleAppearance::None)
.HasState(NS_EVENT_STATE_HOVER);
}
CSSIntCoord ScrollbarDrawingMac::GetScrollbarSize(StyleScrollbarWidth aWidth,
bool aOverlay) {
bool isSmall = aWidth == StyleScrollbarWidth::Thin;
if (aOverlay) {
return isSmall ? 14 : 16;
}
return isSmall ? 11 : 15;
}
LayoutDeviceIntCoord ScrollbarDrawingMac::GetScrollbarSize(
StyleScrollbarWidth aWidth, bool aOverlay, float aDpiRatio) {
CSSIntCoord size = GetScrollbarSize(aWidth, aOverlay);
if (aDpiRatio >= 2.0f) {
return int32_t(size) * 2;
}
return int32_t(size);
}
LayoutDeviceIntSize ScrollbarDrawingMac::GetMinimumWidgetSize(
StyleAppearance aAppearance, nsIFrame* aFrame, float aDpiRatio) {
auto minSize = [&] {
switch (aAppearance) {
case StyleAppearance::ScrollbarthumbHorizontal:
return IntSize{26, 0};
case StyleAppearance::ScrollbarthumbVertical:
return IntSize{0, 26};
case StyleAppearance::ScrollbarVertical:
case StyleAppearance::ScrollbarHorizontal:
case StyleAppearance::ScrollbartrackVertical:
case StyleAppearance::ScrollbartrackHorizontal: {
ComputedStyle* style = nsLayoutUtils::StyleForScrollbar(aFrame);
auto scrollbarWidth = style->StyleUIReset()->mScrollbarWidth;
auto size = GetScrollbarSize(
scrollbarWidth,
LookAndFeel::GetInt(LookAndFeel::IntID::UseOverlayScrollbars));
return IntSize{size, size};
}
case StyleAppearance::MozMenulistArrowButton: {
auto size =
GetScrollbarSize(StyleScrollbarWidth::Auto, /* aOverlay = */ false);
return IntSize{size, size};
}
case StyleAppearance::ScrollbarbuttonUp:
case StyleAppearance::ScrollbarbuttonDown:
return IntSize{15, 16};
case StyleAppearance::ScrollbarbuttonLeft:
case StyleAppearance::ScrollbarbuttonRight:
return IntSize{16, 15};
default:
return IntSize{};
}
}();
if (aDpiRatio >= 2.0f) {
return LayoutDeviceIntSize{minSize.width * 2, minSize.height * 2};
}
return LayoutDeviceIntSize{minSize.width, minSize.height};
}
ScrollbarParams ScrollbarDrawingMac::ComputeScrollbarParams(
nsIFrame* aFrame, const ComputedStyle& aStyle, bool aIsHorizontal) {
ScrollbarParams params;
params.overlay =
nsLookAndFeel::GetInt(LookAndFeel::IntID::UseOverlayScrollbars) != 0;
params.rolledOver = IsParentScrollbarRolledOver(aFrame);
params.small =
aStyle.StyleUIReset()->mScrollbarWidth == StyleScrollbarWidth::Thin;
params.rtl = nsNativeTheme::IsFrameRTL(aFrame);
params.horizontal = aIsHorizontal;
params.onDarkBackground = nsNativeTheme::IsDarkBackground(aFrame);
// Don't use custom scrollbars for overlay scrollbars since they are
// generally good enough for use cases of custom scrollbars.
if (!params.overlay) {
const nsStyleUI* ui = aStyle.StyleUI();
if (ui->HasCustomScrollbars()) {
const auto& colors = ui->mScrollbarColor.AsColors();
params.custom = true;
params.trackColor = colors.track.CalcColor(aStyle);
params.faceColor = colors.thumb.CalcColor(aStyle);
}
}
return params;
}
void ScrollbarDrawingMac::DrawScrollbarThumb(DrawTarget& aDT, const Rect& aRect,
const ScrollbarParams& aParams) {
// Compute the thumb thickness. This varies based on aParams.small,
// aParams.overlay and aParams.rolledOver. non-overlay: 6 / 8, overlay
// non-hovered: 5 / 7, overlay hovered: 9 / 11
float thickness = aParams.small ? 6.0f : 8.0f;
if (aParams.overlay) {
thickness -= 1.0f;
if (aParams.rolledOver) {
thickness += 4.0f;
}
}
// Compute the thumb rect.
float outerSpacing = (aParams.overlay || aParams.small) ? 1.0f : 2.0f;
Rect thumbRect = aRect;
thumbRect.Deflate(1.0f);
if (aParams.horizontal) {
float bottomEdge = thumbRect.YMost() - outerSpacing;
thumbRect.SetBoxY(bottomEdge - thickness, bottomEdge);
} else {
if (aParams.rtl) {
float leftEdge = thumbRect.X() + outerSpacing;
thumbRect.SetBoxX(leftEdge, leftEdge + thickness);
} else {
float rightEdge = thumbRect.XMost() - outerSpacing;
thumbRect.SetBoxX(rightEdge - thickness, rightEdge);
}
}
// Compute the thumb fill color.
nscolor faceColor;
if (aParams.custom) {
faceColor = aParams.faceColor;
} else {
if (aParams.overlay) {
faceColor = aParams.onDarkBackground ? NS_RGBA(255, 255, 255, 128)
: NS_RGBA(0, 0, 0, 128);
} else {
faceColor = aParams.rolledOver ? NS_RGBA(125, 125, 125, 255)
: NS_RGBA(194, 194, 194, 255);
}
}
// Fill the thumb shape with the color.
float cornerRadius =
(aParams.horizontal ? thumbRect.Height() : thumbRect.Width()) / 2.0f;
aDT.FillRoundedRect(RoundedRect(thumbRect, RectCornerRadii(cornerRadius)),
ColorPattern(ToDeviceColor(faceColor)));
// Overlay scrollbars have an additional stroke around the fill.
if (aParams.overlay) {
float strokeOutset = aParams.onDarkBackground ? 0.3f : 0.5f;
float strokeWidth = aParams.onDarkBackground ? 0.6f : 0.8f;
nscolor strokeColor = aParams.onDarkBackground ? NS_RGBA(0, 0, 0, 48)
: NS_RGBA(255, 255, 255, 48);
Rect thumbStrokeRect = thumbRect;
thumbStrokeRect.Inflate(strokeOutset);
float strokeRadius = (aParams.horizontal ? thumbStrokeRect.Height()
: thumbStrokeRect.Width()) /
2.0f;
RefPtr<Path> path = MakePathForRoundedRect(aDT, thumbStrokeRect,
RectCornerRadii(strokeRadius));
aDT.Stroke(path, ColorPattern(ToDeviceColor(strokeColor)),
StrokeOptions(strokeWidth));
}
}
struct ScrollbarTrackDecorationColors {
nscolor mInnerColor = 0;
nscolor mShadowColor = 0;
nscolor mOuterColor = 0;
};
static ScrollbarTrackDecorationColors ComputeScrollbarTrackDecorationColors(
nscolor aTrackColor) {
ScrollbarTrackDecorationColors result;
float luminance = RelativeLuminanceUtils::Compute(aTrackColor);
if (luminance >= 0.5f) {
result.mInnerColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 0.836f);
result.mShadowColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 0.982f);
result.mOuterColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 0.886f);
} else {
result.mInnerColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 1.196f);
result.mShadowColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 1.018f);
result.mOuterColor =
RelativeLuminanceUtils::Adjust(aTrackColor, luminance * 1.129f);
}
return result;
}
void ScrollbarDrawingMac::DrawScrollbarTrack(DrawTarget& aDT, const Rect& aRect,
const ScrollbarParams& aParams) {
if (aParams.overlay && !aParams.rolledOver) {
// Non-hovered overlay scrollbars don't have a track. Draw nothing.
return;
}
nscolor trackColor;
if (aParams.custom) {
trackColor = aParams.trackColor;
} else {
if (aParams.overlay) {
trackColor = aParams.onDarkBackground ? NS_RGBA(201, 201, 201, 38)
: NS_RGBA(250, 250, 250, 191);
} else {
trackColor = NS_RGBA(250, 250, 250, 255);
}
}
float thickness = aParams.horizontal ? aRect.height : aRect.width;
// The scrollbar track is drawn as multiple non-overlapping segments, which
// make up lines of different widths and with slightly different shading.
ScrollbarTrackDecorationColors colors =
ComputeScrollbarTrackDecorationColors(trackColor);
struct {
nscolor color;
float thickness;
} segments[] = {
{colors.mInnerColor, 1.0f},
{colors.mShadowColor, 1.0f},
{trackColor, thickness - 3.0f},
{colors.mOuterColor, 1.0f},
};
// Iterate over the segments "from inside to outside" and fill each segment.
// For horizontal scrollbars, iterate top to bottom.
// For vertical scrollbars, iterate left to right or right to left based on
// aParams.rtl.
float accumulatedThickness = 0.0f;
for (const auto& segment : segments) {
Rect segmentRect = aRect;
float startThickness = accumulatedThickness;
float endThickness = startThickness + segment.thickness;
if (aParams.horizontal) {
segmentRect.SetBoxY(aRect.Y() + startThickness, aRect.Y() + endThickness);
} else {
if (aParams.rtl) {
segmentRect.SetBoxX(aRect.XMost() - endThickness,
aRect.XMost() - startThickness);
} else {
segmentRect.SetBoxX(aRect.X() + startThickness,
aRect.X() + endThickness);
}
}
aDT.FillRect(segmentRect, ColorPattern(ToDeviceColor(segment.color)));
accumulatedThickness = endThickness;
}
}
void ScrollbarDrawingMac::DrawScrollCorner(DrawTarget& aDT, const Rect& aRect,
const ScrollbarParams& aParams) {
if (aParams.overlay && !aParams.rolledOver) {
// Non-hovered overlay scrollbars don't have a corner. Draw nothing.
return;
}
// Draw the following scroll corner.
//
// Output: Rectangles:
// +---+---+----------+---+ +---+---+----------+---+
// | I | S | T ... T | O | | I | S | T ... T | O |
// +---+ | | | +---+---+ | |
// | S S | T ... T | | | S S | T ... T | . |
// +-------+ | . | +-------+----------+ . |
// | T ... T | . | | T ... T | . |
// | . . | . | | . . | |
// | T ... T | | | T ... T | O |
// +------------------+ | +------------------+---+
// | O ... O | | O ... O |
// +----------------------+ +----------------------+
float width = aRect.width;
float height = aRect.height;
nscolor trackColor =
aParams.custom ? aParams.trackColor : NS_RGBA(250, 250, 250, 255);
ScrollbarTrackDecorationColors colors =
ComputeScrollbarTrackDecorationColors(trackColor);
struct {
nscolor color;
Rect relativeRect;
} pieces[] = {
{colors.mInnerColor, {0.0f, 0.0f, 1.0f, 1.0f}},
{colors.mShadowColor, {1.0f, 0.0f, 1.0f, 1.0f}},
{colors.mShadowColor, {0.0f, 1.0f, 2.0f, 1.0f}},
{trackColor, {2.0f, 0.0f, width - 3.0f, 2.0f}},
{trackColor, {0.0f, 2.0f, width - 1.0f, height - 3.0f}},
{colors.mOuterColor, {width - 1.0f, 0.0f, 1.0f, height - 1.0f}},
{colors.mOuterColor, {0.0f, height - 1.0f, width, 1.0f}},
};
for (const auto& piece : pieces) {
Rect pieceRect = piece.relativeRect + aRect.TopLeft();
if (aParams.rtl) {
pieceRect.x = aRect.XMost() - piece.relativeRect.XMost();
}
aDT.FillRect(pieceRect, ColorPattern(ToDeviceColor(piece.color)));
}
}
} // namespace widget
} // namespace mozilla