mozilla
/
gecko-dev
зеркало из https://github.com/mozilla/gecko-dev.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
gecko-dev/gfx/thebes/gfxContext.h

747 строки
21 KiB
C++
Исходник Ответственный История

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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/. */
#ifndef GFX_CONTEXT_H
#define GFX_CONTEXT_H
#include "gfxTypes.h"
#include "gfxASurface.h"
#include "gfxPoint.h"
#include "gfxRect.h"
#include "gfxMatrix.h"
#include "gfxPattern.h"
#include "nsTArray.h"
#include "nsAutoPtr.h"
#include "mozilla/gfx/2D.h"
typedef struct _cairo cairo_t;
class GlyphBufferAzure;
template <typename T> class FallibleTArray;
namespace mozilla {
namespace gfx {
struct RectCornerRadii;
} // namespace gfx
} // namespace mozilla
class ClipExporter;
/**
* This is the main class for doing actual drawing. It is initialized using
* a surface and can be drawn on. It manages various state information like
* a current transformation matrix (CTM), a current path, current color,
* etc.
*
* All drawing happens by creating a path and then stroking or filling it.
* The functions like Rectangle and Arc do not do any drawing themselves.
* When a path is drawn (stroked or filled), it is filled/stroked with a
* pattern set by SetPattern, SetColor or SetSource.
*
* Note that the gfxContext takes coordinates in device pixels,
* as opposed to app units.
*/
class gfxContext final {
typedef mozilla::gfx::CapStyle CapStyle;
typedef mozilla::gfx::JoinStyle JoinStyle;
typedef mozilla::gfx::FillRule FillRule;
typedef mozilla::gfx::Path Path;
typedef mozilla::gfx::Pattern Pattern;
typedef mozilla::gfx::Rect Rect;
typedef mozilla::gfx::RectCornerRadii RectCornerRadii;
NS_INLINE_DECL_REFCOUNTING(gfxContext)
public:
/**
* Initialize this context from a DrawTarget.
* Strips any transform from aTarget.
* aTarget will be flushed in the gfxContext's destructor.
*/
explicit gfxContext(mozilla::gfx::DrawTarget *aTarget,
const mozilla::gfx::Point& aDeviceOffset = mozilla::gfx::Point());
/**
* Create a new gfxContext wrapping aTarget and preserving aTarget's
* transform. Note that the transform is moved from aTarget to the resulting
* gfxContext, aTarget will no longer have its transform.
*/
static already_AddRefed<gfxContext> ContextForDrawTarget(mozilla::gfx::DrawTarget* aTarget);
/**
* Return the current transparency group target, if any, along
* with its device offsets from the top. If no group is
* active, returns the surface the gfxContext was created with,
* and 0,0 in dx,dy.
*/
already_AddRefed<gfxASurface> CurrentSurface(gfxFloat *dx, gfxFloat *dy);
already_AddRefed<gfxASurface> CurrentSurface() {
return CurrentSurface(nullptr, nullptr);
}
/**
* Return the raw cairo_t object.
* XXX this should go away at some point.
*/
cairo_t *GetCairo();
mozilla::gfx::DrawTarget *GetDrawTarget() { return mDT; }
/**
** State
**/
// XXX document exactly what bits are saved
void Save();
void Restore();
/**
** Paths & Drawing
**/
/**
* Fill the current path according to the current settings.
*
* Does not consume the current path.
*/
void Fill();
void Fill(const Pattern& aPattern);
/**
* Forgets the current path.
*/
void NewPath();
/**
* Closes the path, i.e. connects the last drawn point to the first one.
*
* Filling a path will implicitly close it.
*/
void ClosePath();
/**
* Returns the current path.
*/
already_AddRefed<Path> GetPath();
/**
* Sets the given path as the current path.
*/
void SetPath(Path* path);
/**
* Moves the pen to a new point without drawing a line.
*/
void MoveTo(const gfxPoint& pt);
/**
* Returns the current point in the current path.
*/
gfxPoint CurrentPoint();
/**
* Draws a line from the current point to pt.
*
* @see MoveTo
*/
void LineTo(const gfxPoint& pt);
// path helpers
/**
* Draws a line from start to end.
*/
void Line(const gfxPoint& start, const gfxPoint& end); // XXX snapToPixels option?
/**
* Draws the rectangle given by rect.
* @param snapToPixels ?
*/
void Rectangle(const gfxRect& rect, bool snapToPixels = false);
void SnappedRectangle(const gfxRect& rect) { return Rectangle(rect, true); }
/**
** Transformation Matrix manipulation
**/
/**
* Post-multiplies 'other' onto the current CTM, i.e. this
* matrix's transformation will take place before the previously set
* transformations.
*/
void Multiply(const gfxMatrix& other);
/**
* Replaces the current transformation matrix with matrix.
*/
void SetMatrix(const gfxMatrix& matrix);
/**
* Returns the current transformation matrix.
*/
gfxMatrix CurrentMatrix() const;
/**
* Converts a point from device to user coordinates using the inverse
* transformation matrix.
*/
gfxPoint DeviceToUser(const gfxPoint& point) const;
/**
* Converts a size from device to user coordinates. This does not apply
* translation components of the matrix.
*/
gfxSize DeviceToUser(const gfxSize& size) const;
/**
* Converts a rectangle from device to user coordinates; this has the
* same effect as using DeviceToUser on both the rectangle's point and
* size.
*/
gfxRect DeviceToUser(const gfxRect& rect) const;
/**
* Converts a point from user to device coordinates using the transformation
* matrix.
*/
gfxPoint UserToDevice(const gfxPoint& point) const;
/**
* Converts a size from user to device coordinates. This does not apply
* translation components of the matrix.
*/
gfxSize UserToDevice(const gfxSize& size) const;
/**
* Converts a rectangle from user to device coordinates. The
* resulting rectangle is the minimum device-space rectangle that
* encloses the user-space rectangle given.
*/
gfxRect UserToDevice(const gfxRect& rect) const;
/**
* Takes the given rect and tries to align it to device pixels. If
* this succeeds, the method will return true, and the rect will
* be in device coordinates (already transformed by the CTM). If it
* fails, the method will return false, and the rect will not be
* changed.
*
* If ignoreScale is true, then snapping will take place even if
* the CTM has a scale applied. Snapping never takes place if
* there is a rotation in the CTM.
*/
bool UserToDevicePixelSnapped(gfxRect& rect, bool ignoreScale = false) const;
/**
* Takes the given point and tries to align it to device pixels. If
* this succeeds, the method will return true, and the point will
* be in device coordinates (already transformed by the CTM). If it
* fails, the method will return false, and the point will not be
* changed.
*
* If ignoreScale is true, then snapping will take place even if
* the CTM has a scale applied. Snapping never takes place if
* there is a rotation in the CTM.
*/
bool UserToDevicePixelSnapped(gfxPoint& pt, bool ignoreScale = false) const;
/**
** Painting sources
**/
/**
* Set a solid color to use for drawing. This color is in the device color space
* and is not transformed.
*/
void SetDeviceColor(const gfxRGBA& c);
/**
* Gets the current color. It's returned in the device color space.
* returns false if there is something other than a color
* set as the current source (pattern, surface, etc)
*/
bool GetDeviceColor(gfxRGBA& c);
/**
* Set a solid color in the sRGB color space to use for drawing.
* If CMS is not enabled, the color is treated as a device-space color
* and this call is identical to SetDeviceColor().
*/
void SetColor(const gfxRGBA& c);
/**
* Uses a surface for drawing. This is a shorthand for creating a
* pattern and setting it.
*
* @param offset from the source surface, to use only part of it.
* May need to make it negative.
*/
void SetSource(gfxASurface *surface, const gfxPoint& offset = gfxPoint(0.0, 0.0));
/**
* Uses a pattern for drawing.
*/
void SetPattern(gfxPattern *pattern);
/**
* Set the color that text drawn on top of transparent pixels should be
* anti-aliased into.
*/
void SetFontSmoothingBackgroundColor(const mozilla::gfx::Color& aColor);
mozilla::gfx::Color GetFontSmoothingBackgroundColor();
/**
* Get the source pattern (solid color, normal pattern, surface, etc)
*/
already_AddRefed<gfxPattern> GetPattern();
/**
** Painting
**/
/**
* Paints the current source surface/pattern everywhere in the current
* clip region.
*/
void Paint(gfxFloat alpha = 1.0);
/**
** Painting with a Mask
**/
/**
* Like Paint, except that it only draws the source where pattern is
* non-transparent.
*/
void Mask(mozilla::gfx::SourceSurface *aSurface, const mozilla::gfx::Matrix& aTransform);
/**
* Shorthand for creating a pattern and calling the pattern-taking
* variant of Mask.
*/
void Mask(gfxASurface *surface, const gfxPoint& offset = gfxPoint(0.0, 0.0));
void Mask(mozilla::gfx::SourceSurface *surface, float alpha = 1.0f, const mozilla::gfx::Point& offset = mozilla::gfx::Point());
/**
** Line Properties
**/
void SetDash(gfxFloat *dashes, int ndash, gfxFloat offset);
// Return true if dashing is set, false if it's not enabled or the
// context is in an error state. |offset| can be nullptr to mean
// "don't care".
bool CurrentDash(FallibleTArray<gfxFloat>& dashes, gfxFloat* offset) const;
// Returns 0.0 if dashing isn't enabled.
gfxFloat CurrentDashOffset() const;
/**
* Sets the line width that's used for line drawing.
*/
void SetLineWidth(gfxFloat width);
/**
* Returns the currently set line width.
*
* @see SetLineWidth
*/
gfxFloat CurrentLineWidth() const;
/**
* Sets the line caps, i.e. how line endings are drawn.
*/
void SetLineCap(CapStyle cap);
CapStyle CurrentLineCap() const;
/**
* Sets the line join, i.e. how the connection between two lines is
* drawn.
*/
void SetLineJoin(JoinStyle join);
JoinStyle CurrentLineJoin() const;
void SetMiterLimit(gfxFloat limit);
gfxFloat CurrentMiterLimit() const;
/**
** Fill Properties
**/
void SetFillRule(FillRule rule);
FillRule CurrentFillRule() const;
/**
** Operators and Rendering control
**/
// define enum for operators (clear, src, dst, etc)
enum GraphicsOperator {
OPERATOR_SOURCE,
OPERATOR_OVER,
OPERATOR_IN,
OPERATOR_OUT,
OPERATOR_ATOP,
OPERATOR_DEST,
OPERATOR_DEST_OVER,
OPERATOR_DEST_IN,
OPERATOR_DEST_OUT,
OPERATOR_DEST_ATOP,
OPERATOR_XOR,
OPERATOR_ADD,
OPERATOR_SATURATE,
OPERATOR_MULTIPLY,
OPERATOR_SCREEN,
OPERATOR_OVERLAY,
OPERATOR_DARKEN,
OPERATOR_LIGHTEN,
OPERATOR_COLOR_DODGE,
OPERATOR_COLOR_BURN,
OPERATOR_HARD_LIGHT,
OPERATOR_SOFT_LIGHT,
OPERATOR_DIFFERENCE,
OPERATOR_EXCLUSION,
OPERATOR_HUE,
OPERATOR_SATURATION,
OPERATOR_COLOR,
OPERATOR_LUMINOSITY
};
/**
* Sets the operator used for all further drawing. The operator affects
* how drawing something will modify the destination. For example, the
* OVER operator will do alpha blending of source and destination, while
* SOURCE will replace the destination with the source.
*/
void SetOperator(GraphicsOperator op);
GraphicsOperator CurrentOperator() const;
void SetAntialiasMode(mozilla::gfx::AntialiasMode mode);
mozilla::gfx::AntialiasMode CurrentAntialiasMode() const;
/**
** Clipping
**/
/**
* Clips all further drawing to the current path.
* This does not consume the current path.
*/
void Clip();
/**
* Helper functions that will create a rect path and call Clip().
* Any current path will be destroyed by these functions!
*/
void Clip(const Rect& rect);
void Clip(const gfxRect& rect); // will clip to a rect
void Clip(Path* aPath);
void PopClip();
/**
* This will return the current bounds of the clip region in user
* space.
*/
gfxRect GetClipExtents();
/**
* Whether the current clip is not a simple rectangle.
*/
bool HasComplexClip() const;
/**
* Returns true if the given rectangle is fully contained in the current clip.
* This is conservative; it may return false even when the given rectangle is
* fully contained by the current clip.
*/
bool ClipContainsRect(const gfxRect& aRect);
/**
* Exports the current clip using the provided exporter.
*/
bool ExportClip(ClipExporter& aExporter);
/**
* Groups
*/
void PushGroup(gfxContentType content = gfxContentType::COLOR);
/**
* Like PushGroup, but if the current surface is gfxContentType::COLOR and
* content is gfxContentType::COLOR_ALPHA, makes the pushed surface gfxContentType::COLOR
* instead and copies the contents of the current surface to the pushed
* surface. This is good for pushing opacity groups, since blending the
* group back to the current surface with some alpha applied will give
* the correct results and using an opaque pushed surface gives better
* quality and performance.
* This API really only makes sense if you do a PopGroupToSource and
* immediate Paint with OPERATOR_OVER.
*/
void PushGroupAndCopyBackground(gfxContentType content = gfxContentType::COLOR);
already_AddRefed<gfxPattern> PopGroup();
void PopGroupToSource();
already_AddRefed<mozilla::gfx::SourceSurface>
PopGroupToSurface(mozilla::gfx::Matrix* aMatrix);
mozilla::gfx::Point GetDeviceOffset() const;
// Work out whether cairo will snap inter-glyph spacing to pixels.
void GetRoundOffsetsToPixels(bool *aRoundX, bool *aRoundY);
#ifdef MOZ_DUMP_PAINTING
/**
* Debug functions to encode the current surface as a PNG and export it.
*/
/**
* Writes a binary PNG file.
*/
void WriteAsPNG(const char* aFile);
/**
* Write as a PNG encoded Data URL to stdout.
*/
void DumpAsDataURI();
/**
* Copy a PNG encoded Data URL to the clipboard.
*/
void CopyAsDataURI();
#endif
static mozilla::gfx::UserDataKey sDontUseAsSourceKey;
private:
~gfxContext();
friend class PatternFromState;
friend class GlyphBufferAzure;
typedef mozilla::gfx::Matrix Matrix;
typedef mozilla::gfx::DrawTarget DrawTarget;
typedef mozilla::gfx::Color Color;
typedef mozilla::gfx::StrokeOptions StrokeOptions;
typedef mozilla::gfx::Float Float;
typedef mozilla::gfx::CompositionOp CompositionOp;
typedef mozilla::gfx::PathBuilder PathBuilder;
typedef mozilla::gfx::SourceSurface SourceSurface;
struct AzureState {
AzureState()
: op(mozilla::gfx::CompositionOp::OP_OVER)
, color(0, 0, 0, 1.0f)
, clipWasReset(false)
, fillRule(mozilla::gfx::FillRule::FILL_WINDING)
, aaMode(mozilla::gfx::AntialiasMode::SUBPIXEL)
, patternTransformChanged(false)
{}
mozilla::gfx::CompositionOp op;
Color color;
nsRefPtr<gfxPattern> pattern;
nsRefPtr<gfxASurface> sourceSurfCairo;
mozilla::RefPtr<SourceSurface> sourceSurface;
mozilla::gfx::Point sourceSurfaceDeviceOffset;
Matrix surfTransform;
Matrix transform;
struct PushedClip {
mozilla::RefPtr<Path> path;
Rect rect;
Matrix transform;
};
nsTArray<PushedClip> pushedClips;
nsTArray<Float> dashPattern;
bool clipWasReset;
mozilla::gfx::FillRule fillRule;
StrokeOptions strokeOptions;
mozilla::RefPtr<DrawTarget> drawTarget;
mozilla::RefPtr<DrawTarget> parentTarget;
mozilla::gfx::AntialiasMode aaMode;
bool patternTransformChanged;
Matrix patternTransform;
Color fontSmoothingBackgroundColor;
// This is used solely for using minimal intermediate surface size.
mozilla::gfx::Point deviceOffset;
};
// This ensures mPath contains a valid path (in user space!)
void EnsurePath();
// This ensures mPathBuilder contains a valid PathBuilder (in user space!)
void EnsurePathBuilder();
void FillAzure(const Pattern& aPattern, mozilla::gfx::Float aOpacity);
void PushClipsToDT(mozilla::gfx::DrawTarget *aDT);
CompositionOp GetOp();
void ChangeTransform(const mozilla::gfx::Matrix &aNewMatrix, bool aUpdatePatternTransform = true);
Rect GetAzureDeviceSpaceClipBounds();
Matrix GetDeviceTransform() const;
Matrix GetDTTransform() const;
void PushNewDT(gfxContentType content);
bool mPathIsRect;
bool mTransformChanged;
Matrix mPathTransform;
Rect mRect;
mozilla::RefPtr<PathBuilder> mPathBuilder;
mozilla::RefPtr<Path> mPath;
Matrix mTransform;
nsTArray<AzureState> mStateStack;
AzureState &CurrentState() { return mStateStack[mStateStack.Length() - 1]; }
const AzureState &CurrentState() const { return mStateStack[mStateStack.Length() - 1]; }
cairo_t *mRefCairo;
mozilla::RefPtr<DrawTarget> mDT;
mozilla::RefPtr<DrawTarget> mOriginalDT;
};
/**
* Sentry helper class for functions with multiple return points that need to
* call Save() on a gfxContext and have Restore() called automatically on the
* gfxContext before they return.
*/
class gfxContextAutoSaveRestore
{
public:
gfxContextAutoSaveRestore() : mContext(nullptr) {}
explicit gfxContextAutoSaveRestore(gfxContext *aContext) : mContext(aContext) {
mContext->Save();
}
~gfxContextAutoSaveRestore() {
Restore();
}
void SetContext(gfxContext *aContext) {
NS_ASSERTION(!mContext, "Not going to call Restore() on some context!!!");
mContext = aContext;
mContext->Save();
}
void EnsureSaved(gfxContext *aContext) {
MOZ_ASSERT(!mContext || mContext == aContext, "wrong context");
if (!mContext) {
mContext = aContext;
mContext->Save();
}
}
void Restore() {
if (mContext) {
mContext->Restore();
mContext = nullptr;
}
}
private:
gfxContext *mContext;
};
/**
* Sentry helper class for functions with multiple return points that need to
* back up the current matrix of a context and have it automatically restored
* before they return.
*/
class gfxContextMatrixAutoSaveRestore
{
public:
gfxContextMatrixAutoSaveRestore() :
mContext(nullptr)
{
}
explicit gfxContextMatrixAutoSaveRestore(gfxContext *aContext) :
mContext(aContext), mMatrix(aContext->CurrentMatrix())
{
}
~gfxContextMatrixAutoSaveRestore()
{
if (mContext) {
mContext->SetMatrix(mMatrix);
}
}
void SetContext(gfxContext *aContext)
{
NS_ASSERTION(!mContext, "Not going to restore the matrix on some context!");
mContext = aContext;
mMatrix = aContext->CurrentMatrix();
}
void Restore()
{
if (mContext) {
mContext->SetMatrix(mMatrix);
}
}
const gfxMatrix& Matrix()
{
MOZ_ASSERT(mContext, "mMatrix doesn't contain a useful matrix");
return mMatrix;
}
private:
gfxContext *mContext;
gfxMatrix mMatrix;
};
class gfxContextAutoDisableSubpixelAntialiasing {
public:
gfxContextAutoDisableSubpixelAntialiasing(gfxContext *aContext, bool aDisable)
{
if (aDisable) {
mDT = aContext->GetDrawTarget();
mSubpixelAntialiasingEnabled = mDT->GetPermitSubpixelAA();
mDT->SetPermitSubpixelAA(false);
}
}
~gfxContextAutoDisableSubpixelAntialiasing()
{
if (mDT) {
mDT->SetPermitSubpixelAA(mSubpixelAntialiasingEnabled);
}
}
private:
mozilla::RefPtr<mozilla::gfx::DrawTarget> mDT;
bool mSubpixelAntialiasingEnabled;
};
/* This class lives on the stack and allows gfxContext users to easily, and
* performantly get a gfx::Pattern to use for drawing in their current context.
*/
class PatternFromState
{
public:
explicit PatternFromState(gfxContext *aContext) : mContext(aContext), mPattern(nullptr) {}
~PatternFromState() { if (mPattern) { mPattern->~Pattern(); } }
operator mozilla::gfx::Pattern&();
private:
union {
mozilla::AlignedStorage2<mozilla::gfx::ColorPattern> mColorPattern;
mozilla::AlignedStorage2<mozilla::gfx::SurfacePattern> mSurfacePattern;
};
gfxContext *mContext;
mozilla::gfx::Pattern *mPattern;
};
/* This interface should be implemented to handle exporting the clip from a context.
*/
class ClipExporter : public mozilla::gfx::PathSink {
public:
virtual void BeginClip(const mozilla::gfx::Matrix& aMatrix) = 0;
virtual void EndClip() = 0;
};
#endif /* GFX_CONTEXT_H */
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку