gecko-dev/gfx/public/nsIRenderingContext.h

592 lines
21 KiB
C++

/* -*- 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 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#ifndef nsIRenderingContext_h___
#define nsIRenderingContext_h___
#include "nscore.h"
#include "nsISupports.h"
#include "nsColor.h"
#include "nsCoord.h"
class nsIWidget;
class nsIFontMetrics;
class nsIImage;
class nsTransform2D;
class nsString;
class nsIDeviceContext;
class nsIRegion;
struct nsFont;
struct nsPoint;
struct nsRect;
//cliprect/region combination methods
typedef enum
{
nsClipCombine_kIntersect = 0,
nsClipCombine_kUnion = 1,
nsClipCombine_kSubtract = 2,
nsClipCombine_kReplace = 3
} nsClipCombine;
//linestyles
typedef enum
{
nsLineStyle_kNone = 0,
nsLineStyle_kSolid = 1,
nsLineStyle_kDashed = 2,
nsLineStyle_kDotted = 3
} nsLineStyle;
// IID for the nsIRenderingContext interface
#define NS_IRENDERING_CONTEXT_IID \
{ 0xa6cf9068, 0x15b3, 0x11d2,{0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32}}
//----------------------------------------------------------------------
//a cross platform way of specifying a native rendering context
typedef void * nsDrawingSurface;
// RenderingContext interface
class nsIRenderingContext : public nsISupports
{
public:
static const nsIID& IID() { static nsIID iid = NS_IRENDERING_CONTEXT_IID; return iid; }
//TBD: bind/unbind, transformation of scalars (hacky),
//potential drawmode for selection, polygons. MMP
/**
* Initialize the RenderingContext
* @param aContext the device context to use.
* @param aWidget the widget to hook up to
* @result The result of the initialization, NS_Ok if no errors
*/
NS_IMETHOD Init(nsIDeviceContext* aContext, nsIWidget *aWidget) = 0;
/**
* Initialize the RenderingContext
* @param aContext the device context to use for the drawing.
* @param aSurface the surface to draw into
* @result The result of the initialization, NS_Ok if no errors
*/
NS_IMETHOD Init(nsIDeviceContext* aContext, nsDrawingSurface aSurface) = 0;
/**
* Reset the rendering context
*/
NS_IMETHOD Reset(void) = 0;
/**
* Get the DeviceContext that this RenderingContext was initialized with
* @result the device context
*/
NS_IMETHOD GetDeviceContext(nsIDeviceContext *& aDeviceContext) = 0;
/**
* Selects an offscreen drawing surface into the RenderingContext to draw to.
* @param aSurface is the offscreen surface we are going to draw to.
* if nsnull, the original drawing surface obtained at initialization
* should be selected.
*/
NS_IMETHOD SelectOffScreenDrawingSurface(nsDrawingSurface aSurface) = 0;
/**
* Returns in aResult any rendering hints that the context has.
* See below for the hints bits. Always returns NS_OK.
*/
NS_IMETHOD GetHints(PRUint32& aResult) = 0;
/**
* Save a graphical state onto a stack.
*/
NS_IMETHOD PushState(void) = 0;
/**
* Get and and set RenderingContext to this graphical state
* @return if PR_TRUE, indicates that the clipping region after
* popping state is empty, else PR_FALSE
*/
NS_IMETHOD PopState(PRBool &aClipEmpty) = 0;
/**
* Tells if a given rectangle is visible within the rendering context
* @param aRect is the rectangle that will be checked for visiblity
* @result If true, that rectanglular area is visable.
*/
NS_IMETHOD IsVisibleRect(const nsRect& aRect, PRBool &aIsVisible) = 0;
/**
* Sets the clipping for the RenderingContext to the passed in rectangle
* @param aRect The rectangle to set the clipping rectangle to
* @param aCombine how to combine this rect with the current clip region.
* see the bottom of nsIRenderingContext.h
* @return PR_TRUE if the clip region is now empty, else PR_FALSE
*/
NS_IMETHOD SetClipRect(const nsRect& aRect, nsClipCombine aCombine, PRBool &aClipEmpty) = 0;
/**
* Gets the bounds of the clip region of the RenderingContext
* @param aRect out parameter to contain the clip region bounds
* for the RenderingContext
* @return PR_TRUE if the rendering context has a local cliprect set
* else aRect is undefined
*/
NS_IMETHOD GetClipRect(nsRect &aRect, PRBool &aHasLocalClip) = 0;
/**
* Sets the line style for the RenderingContext
* @param aLineStyle The line style
* @return NS_OK if the line style is correctly set
*/
NS_IMETHOD SetLineStyle(nsLineStyle aLineStyle) = 0;
/**
* Gets the line style for the RenderingContext
* @param aLineStyle The line style to be retrieved
* @return NS_OK if the line style is correctly retrieved
*/
NS_IMETHOD GetLineStyle(nsLineStyle &aLineStyle) = 0;
/**
* Sets the clipping for the RenderingContext to the passed in region
* @param aRegion The region to set the clipping area to
* @param aCombine how to combine this region with the current clip region.
* see the bottom of nsIRenderingContext.h
* @return PR_TRUE if the clip region is now empty, else PR_FALSE
*/
NS_IMETHOD SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine, PRBool &aClipEmpty) = 0;
/**
* Gets the current clipping region for the RenderingContext
* @param aRegion out parameter representing the clip region.
* if SetClipRegion() is called, do not assume that GetClipRegion()
* will return the same object.
*/
NS_IMETHOD GetClipRegion(nsIRegion **aRegion) = 0;
/**
* Sets the forground color for the RenderingContext
* @param aColor The color to set the RenderingContext to
*/
NS_IMETHOD SetColor(nscolor aColor) = 0;
/**
* Get the forground color for the RenderingContext
* @return The current forground color of the RenderingContext
*/
NS_IMETHOD GetColor(nscolor &aColor) const = 0;
/**
* Sets the font for the RenderingContext
* @param aFont The font to use in the RenderingContext
*/
NS_IMETHOD SetFont(const nsFont& aFont) = 0;
/**
* Sets the font for the RenderingContext
* @param aFontMetric The font metrics representing the
* font to use in the RenderingContext
*/
NS_IMETHOD SetFont(nsIFontMetrics *aFontMetrics) = 0;
/**
* Get the current fontmetrics for the RenderingContext
* @return The current font of the RenderingContext
*/
NS_IMETHOD GetFontMetrics(nsIFontMetrics *&aFontMetrics) = 0;
/**
* Add in a translate to the RenderingContext's transformation matrix
* @param aX The horizontal translation
* @param aY The vertical translation
*/
NS_IMETHOD Translate(nscoord aX, nscoord aY) = 0;
/**
* Add in a scale to the RenderingContext's transformation matrix
* @param aX The horizontal scale
* @param aY The vertical scale
*/
NS_IMETHOD Scale(float aSx, float aSy) = 0;
/**
* Get the current transformation matrix for the RenderingContext
* @return The transformation matrix for the RenderingContext
*/
NS_IMETHOD GetCurrentTransform(nsTransform2D *&aTransform) = 0;
/**
* Create an offscreen drawing surface compatible with this RenderingContext.
* The rect passed in is not affected by any transforms in the rendering
* context and the values are in device units.
* @param aBounds A rectangle representing the size for the drawing surface.
* if nsnull then a bitmap will not be created and associated
* with the new drawing surface
* @param aSurfFlags see bottom of nsIRenderingContext.h
* @return A nsDrawingSurface
*/
NS_IMETHOD CreateDrawingSurface(nsRect *aBounds, PRUint32 aSurfFlags, nsDrawingSurface &aSurface) = 0;
/**
* Destroy a drawing surface created by CreateDrawingSurface()
* @param aDS A drawing surface to destroy
*/
NS_IMETHOD DestroyDrawingSurface(nsDrawingSurface aDS) = 0;
/**
* Draw a line
* @param aXO starting horiztonal coord in twips
* @param aY0 starting vertical coord in twips
* @param aX1 end horiztonal coord in twips
* @param aY1 end vertical coord in twips
*/
NS_IMETHOD DrawLine(nscoord aX0, nscoord aY0, nscoord aX1, nscoord aY1) = 0;
/**
* Draw a polyline
* @param aPoints array of endpoints
* @param aNumPonts number of points
*/
NS_IMETHOD DrawPolyline(const nsPoint aPoints[], PRInt32 aNumPoints) = 0;
/**
* Draw a rectangle
* @param aRect The rectangle to draw
*/
NS_IMETHOD DrawRect(const nsRect& aRect) = 0;
/**
* Draw a rectangle
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of rectangle in twips
* @param aHeight Height of rectangle in twips
*/
NS_IMETHOD DrawRect(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight) = 0;
/**
* Fill a rectangle in the current foreground color
* @param aRect The rectangle to draw
*/
NS_IMETHOD FillRect(const nsRect& aRect) = 0;
/**
* Fill a rectangle in the current foreground color
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of rectangle in twips
* @param aHeight Height of rectangle in twips
*/
NS_IMETHOD FillRect(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight) = 0;
/**
* Draw a poly in the current foreground color
* @param aPoints points to use for the drawing, last must equal first
* @param aNumPonts number of points in the polygon
*/
NS_IMETHOD DrawPolygon(const nsPoint aPoints[], PRInt32 aNumPoints) = 0;
/**
* Fill a poly in the current foreground color
* @param aPoints points to use for the drawing, last must equal first
* @param aNumPonts number of points in the polygon
*/
NS_IMETHOD FillPolygon(const nsPoint aPoints[], PRInt32 aNumPoints) = 0;
/**
* Draw an ellipse in the current foreground color
* @param aRect The rectangle define bounds of ellipse to draw
*/
NS_IMETHOD DrawEllipse(const nsRect& aRect) = 0;
/**
* Draw an ellipse in the current foreground color
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of horizontal axis in twips
* @param aHeight Height of vertical axis in twips
*/
NS_IMETHOD DrawEllipse(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight) = 0;
/**
* Fill an ellipse in the current foreground color
* @param aRect The rectangle define bounds of ellipse to draw
*/
NS_IMETHOD FillEllipse(const nsRect& aRect) = 0;
/**
* Fill an ellipse in the current foreground color
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of horizontal axis in twips
* @param aHeight Height of vertical axis in twips
*/
NS_IMETHOD FillEllipse(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight) = 0;
/**
* Draw an arc in the current forground color
* @param aRect The rectangle define bounds of ellipse to use
* @param aStartAngle the starting angle of the arc, in the ellipse
* @param aEndAngle The ending angle of the arc, in the ellipse
*/
NS_IMETHOD DrawArc(const nsRect& aRect,
float aStartAngle, float aEndAngle) = 0;
/**
* Draw an arc in the current forground color
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of horizontal axis in twips
* @param aHeight Height of vertical axis in twips
* @param aStartAngle the starting angle of the arc, in the ellipse
* @param aEndAngle The ending angle of the arc, in the ellipse
*/
NS_IMETHOD DrawArc(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight,
float aStartAngle, float aEndAngle) = 0;
/**
* Fill an arc in the current forground color
* @param aRect The rectangle define bounds of ellipse to use
* @param aStartAngle the starting angle of the arc, in the ellipse
* @param aEndAngle The ending angle of the arc, in the ellipse
*/
NS_IMETHOD FillArc(const nsRect& aRect,
float aStartAngle, float aEndAngle) = 0;
/**
* Fill an arc in the current forground color
* @param aX Horizontal left Coordinate in twips
* @param aY Vertical top Coordinate in twips
* @param aWidth Width of horizontal axis in twips
* @param aHeight Height of vertical axis in twips
* @param aStartAngle the starting angle of the arc, in the ellipse
* @param aEndAngle The ending angle of the arc, in the ellipse
*/
NS_IMETHOD FillArc(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight,
float aStartAngle, float aEndAngle) = 0;
/**
* Returns the width (in app units) of an 8-bit character
* If no font has been Set, the results are undefined.
* @param aC character to measure
* @param aWidth out parameter for width
* @return error status
*/
NS_IMETHOD GetWidth(char aC, nscoord &aWidth) = 0;
/**
* Returns the width (in app units) of a unicode character
* If no font has been Set, the results are undefined.
* @param aC character to measure
* @param aWidth out parameter for width
* @param aFontID an optional out parameter used to store a
* font identifier that can be passed into the DrawString()
* methods to speed rendering
* @return error status
*/
NS_IMETHOD GetWidth(PRUnichar aC, nscoord &aWidth,
PRInt32 *aFontID = nsnull) = 0;
/**
* Returns the width (in app units) of an nsString
* If no font has been Set, the results are undefined.
* @param aString string to measure
* @param aWidth out parameter for width
* @param aFontID an optional out parameter used to store a
* font identifier that can be passed into the DrawString()
* methods to speed rendering
* @return error status
*/
NS_IMETHOD GetWidth(const nsString& aString, nscoord &aWidth,
PRInt32 *aFontID = nsnull) = 0;
/**
* Returns the width (in app units) of an 8-bit character string
* If no font has been Set, the results are undefined.
* @param aString string to measure
* @param aWidth out parameter for width
* @return error status
*/
NS_IMETHOD GetWidth(const char* aString, nscoord& aWidth) = 0;
/**
* Returns the width (in app units) of an 8-bit character string
* If no font has been Set, the results are undefined.
* @param aString string to measure
* @param aLength number of characters in string
* @param aWidth out parameter for width
* @return error status
*/
NS_IMETHOD GetWidth(const char* aString, PRUint32 aLength,
nscoord& aWidth) = 0;
/**
* Returns the width (in app units) of a Unicode character string
* If no font has been Set, the results are undefined.
* @param aString string to measure
* @param aLength number of characters in string
* @param aWidth out parameter for width
* @param aFontID an optional out parameter used to store a
* font identifier that can be passed into the DrawString()
* methods to speed rendering
* @return error status
*/
NS_IMETHOD GetWidth(const PRUnichar *aString, PRUint32 aLength,
nscoord &aWidth, PRInt32 *aFontID = nsnull) = 0;
/**
* Draw a string in the RenderingContext
* @param aString The string to draw
* @param aLength The length of the aString
* @param aX Horizontal starting point of baseline
* @param aY Vertical starting point of baseline.
* @param aSpacing inter-character spacing to apply
*/
NS_IMETHOD DrawString(const char *aString, PRUint32 aLength,
nscoord aX, nscoord aY,
const nscoord* aSpacing = nsnull) = 0;
/**
* Draw a string in the RenderingContext
* @param aString A PRUnichar of the string
* @param aLength The length of the aString
* @param aX Horizontal starting point of baseline
* @param aY Vertical starting point of baseline.
* @param aFontID an optional parameter used to speed font
* selection for complex unicode strings. the value
* passed is returned by the DrawString() methods.
* @param aSpacing inter-character spacing to apply
*/
NS_IMETHOD DrawString(const PRUnichar *aString, PRUint32 aLength,
nscoord aX, nscoord aY,
PRInt32 aFontID = -1,
const nscoord* aSpacing = nsnull) = 0;
/**
* Draw a string in the RenderingContext
* @param aString A nsString of the string
* @param aX Horizontal starting point of baseline
* @param aY Vertical starting point of baseline.
* @param aFontID an optional parameter used to speed font
* selection for complex unicode strings. the value
* passed is returned by the DrawString() methods.
* @param aSpacing inter-character spacing to apply
*/
NS_IMETHOD DrawString(const nsString& aString, nscoord aX, nscoord aY,
PRInt32 aFontID = -1,
const nscoord* aSpacing = nsnull) = 0;
/**
* Copy an image to the RenderingContext
* @param aX Horzontal left destination coordinate
* @param aY Vertical top of destinatio coordinate
*/
NS_IMETHOD DrawImage(nsIImage *aImage, nscoord aX, nscoord aY) = 0;
/**
* Copy an image to the RenderingContext, scaling can occur if width/hieght does not match source
* @param aX Horzontal left destination coordinate
* @param aY Vertical top of destinatio coordinate
* @param aWidth Width of destination,
* @param aHeight Height of destination
*/
NS_IMETHOD DrawImage(nsIImage *aImage, nscoord aX, nscoord aY,
nscoord aWidth, nscoord aHeight) = 0;
/**
* Copy an image to the RenderingContext, scaling can occur if source/dest rects differ
* @param aRect Destination rectangle to copy the image to
*/
NS_IMETHOD DrawImage(nsIImage *aImage, const nsRect& aRect) = 0;
/**
* Copy an image to the RenderingContext, scaling/clipping can occur if source/dest rects differ
* @param aSRect Source rectangle to copy from
* @param aDRect Destination rectangle to copy the image to
*/
NS_IMETHOD DrawImage(nsIImage *aImage, const nsRect& aSRect, const nsRect& aDRect)=0;
/**
* Copy offscreen pixelmap to this RenderingContext.
* @param aSrcSurf drawing surface to copy bits from
* @param aSrcX x offset into source pixelmap to copy from
* @param aSrcY y offset into source pixelmap to copy from
* @param aDestBounds Destination rectangle to copy to
* @param aCopyFlags see below
*/
NS_IMETHOD CopyOffScreenBits(nsDrawingSurface aSrcSurf, PRInt32 aSrcX, PRInt32 aSrcY,
const nsRect &aDestBounds, PRUint32 aCopyFlags) = 0;
};
//modifiers for text rendering
#define NS_DRAWSTRING_NORMAL 0x0
#define NS_DRAWSTRING_UNDERLINE 0x1
#define NS_DRAWSTRING_OVERLINE 0x2
#define NS_DRAWSTRING_LINE_THROUGH 0x4
// Bit values for GetHints
/**
* This bit, when set, indicates that the underlying rendering system
* prefers 8 bit text rendering over PRUnichar text rendering. When this
* bit is <b>not</b> set the opposite is true: the system prefers PRUnichar
* rendering, not 8 bit rendering.
*/
#define NS_RENDERING_HINT_FAST_8BIT_TEXT 0x1
/**
* This bit, when set, indicates that the rendering is being done
* remotely.
*/
#define NS_RENDERING_HINT_REMOTE_RENDERING 0x2
//flags for copy CopyOffScreenBits
//when performing the blit, use the region, if any,
//that exists in the source drawingsurface as a
//blit mask.
#define NS_COPYBITS_USE_SOURCE_CLIP_REGION 0x0001
//transform the source offsets by the xform in the
//rendering context
#define NS_COPYBITS_XFORM_SOURCE_VALUES 0x0002
//transform the destination rect by the xform in the
//rendering context
#define NS_COPYBITS_XFORM_DEST_VALUES 0x0004
//this is basically a hack and is used by callers
//who have selected an alternate drawing surface and
//wish the copy to happen to that buffer rather than
//the "front" buffer. i'm not proud of this. MMP
#define NS_COPYBITS_TO_BACK_BUFFER 0x0008
//when creating a drawing surface, you can use this
//to tell the rendering context that you anticipate
//the need to get to the actual bits of the drawing
//surface at some point during it's lifetime. typically
//used when creating bitmaps to be operated on by the
//nsIBlender implementations.
#define NS_CREATEDRAWINGSURFACE_FOR_PIXEL_ACCESS 0x0001
#endif /* nsIRenderingContext_h___ */