/
CairoOperations.cpp
1284 lines (1091 loc) · 52.7 KB
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CairoOperations.cpp
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/*
* Copyright (C) 2006 Apple Inc. All rights reserved.
* Copyright (C) 2007 Alp Toker <alp@atoker.com>
* Copyright (C) 2008, 2009 Dirk Schulze <krit@webkit.org>
* Copyright (C) 2008 Nuanti Ltd.
* Copyright (C) 2009 Brent Fulgham <bfulgham@webkit.org>
* Copyright (C) 2010, 2011 Igalia S.L.
* Copyright (C) Research In Motion Limited 2010. All rights reserved.
* Copyright (C) 2012, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "CairoOperations.h"
#if USE(CAIRO)
#include "CairoUniquePtr.h"
#include "CairoUtilities.h"
#include "DrawErrorUnderline.h"
#include "FloatConversion.h"
#include "FloatRect.h"
#include "Gradient.h"
#include "GraphicsContext.h"
#include "GraphicsContextCairo.h"
#include "Image.h"
#include "ImageBuffer.h"
#include "NativeImage.h"
#include "Path.h"
#include "ShadowBlur.h"
#include <algorithm>
#include <cairo.h>
namespace WebCore {
namespace Cairo {
enum PatternAdjustment { NoAdjustment, AdjustPatternForGlobalAlpha };
enum AlphaPreservation { DoNotPreserveAlpha, PreserveAlpha };
static void reduceSourceByAlpha(cairo_t* cr, float alpha)
{
if (alpha >= 1)
return;
cairo_push_group(cr);
cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
cairo_paint_with_alpha(cr, alpha);
cairo_pop_group_to_source(cr);
}
static void prepareCairoContextSource(cairo_t* cr, cairo_pattern_t* pattern, cairo_pattern_t* gradient, const Color& color, float globalAlpha)
{
if (pattern) {
// Pattern source
cairo_set_source(cr, pattern);
reduceSourceByAlpha(cr, globalAlpha);
} else if (gradient) {
// Gradient source
cairo_set_source(cr, gradient);
} else {
// Solid color source
if (globalAlpha < 1)
setSourceRGBAFromColor(cr, color.colorWithAlphaMultipliedBy(globalAlpha));
else
setSourceRGBAFromColor(cr, color);
}
}
static void clipForPatternFilling(cairo_t* cr, const FloatSize& patternSize, const AffineTransform& patternTransform, bool repeatX, bool repeatY)
{
// Hold current cairo path in a variable for restoring it after configuring the pattern clip rectangle.
CairoUniquePtr<cairo_path_t> currentPath(cairo_copy_path(cr));
cairo_new_path(cr);
// Initialize clipping extent from current cairo clip extents, then shrink if needed according to pattern.
// Inspired by GraphicsContextQt::drawRepeatPattern.
double x1, y1, x2, y2;
cairo_clip_extents(cr, &x1, &y1, &x2, &y2);
FloatRect clipRect(x1, y1, x2 - x1, y2 - y1);
FloatRect patternRect = patternTransform.mapRect(FloatRect(FloatPoint(), patternSize));
if (!repeatX) {
clipRect.setX(patternRect.x());
clipRect.setWidth(patternRect.width());
}
if (!repeatY) {
clipRect.setY(patternRect.y());
clipRect.setHeight(patternRect.height());
}
if (!repeatX || !repeatY) {
cairo_rectangle(cr, clipRect.x(), clipRect.y(), clipRect.width(), clipRect.height());
cairo_clip(cr);
}
// Restoring cairo path.
cairo_append_path(cr, currentPath.get());
}
static void prepareForFilling(cairo_t* cr, const Cairo::FillSource& fillSource, PatternAdjustment patternAdjustment)
{
cairo_set_fill_rule(cr, fillSource.fillRule == WindRule::EvenOdd ? CAIRO_FILL_RULE_EVEN_ODD : CAIRO_FILL_RULE_WINDING);
bool adjustForAlpha = patternAdjustment == AdjustPatternForGlobalAlpha;
auto* gradient = fillSource.gradient.base.get();
if (adjustForAlpha && fillSource.gradient.alphaAdjusted)
gradient = fillSource.gradient.alphaAdjusted.get();
prepareCairoContextSource(cr, fillSource.pattern.object.get(), gradient,
fillSource.color, adjustForAlpha ? fillSource.globalAlpha : 1);
if (fillSource.pattern.object) {
clipForPatternFilling(cr, fillSource.pattern.size, fillSource.pattern.transform,
fillSource.pattern.repeatX, fillSource.pattern.repeatY);
}
}
static void prepareForStroking(cairo_t* cr, const Cairo::StrokeSource& strokeSource, AlphaPreservation alphaPreservation)
{
bool preserveAlpha = alphaPreservation == PreserveAlpha;
auto* gradient = strokeSource.gradient.base.get();
if (preserveAlpha && strokeSource.gradient.alphaAdjusted)
gradient = strokeSource.gradient.alphaAdjusted.get();
prepareCairoContextSource(cr, strokeSource.pattern.get(), gradient,
strokeSource.color, preserveAlpha ? strokeSource.globalAlpha : 1);
}
static void drawPatternToCairoContext(cairo_t* cr, cairo_pattern_t* pattern, const FloatRect& destRect, float alpha)
{
cairo_translate(cr, destRect.x(), destRect.y());
cairo_set_source(cr, pattern);
cairo_rectangle(cr, 0, 0, destRect.width(), destRect.height());
cairo_clip(cr);
cairo_paint_with_alpha(cr, std::max<float>(0, std::min<float>(1.0, alpha)));
}
static inline void fillRectWithColor(cairo_t* cr, const FloatRect& rect, const Color& color)
{
if (!color.isVisible() && cairo_get_operator(cr) == CAIRO_OPERATOR_OVER)
return;
setSourceRGBAFromColor(cr, color);
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
cairo_fill(cr);
}
enum PathDrawingStyle {
Fill = 1,
Stroke = 2,
FillAndStroke = Fill + Stroke
};
static void drawShadowLayerBuffer(GraphicsContextCairo& platformContext, ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize, const ShadowState& shadowState)
{
if (auto nativeImage = layerImage.copyNativeImage(DontCopyBackingStore)) {
drawPlatformImage(platformContext, nativeImage->platformImage().get(), FloatRect(roundedIntPoint(layerOrigin), layerSize), FloatRect(FloatPoint(), layerSize), { shadowState.globalCompositeOperator }, shadowState.globalAlpha, ShadowState());
}
}
// FIXME: This is mostly same as drawShadowLayerBuffer, so we should merge two.
static void drawShadowImage(GraphicsContextCairo& platformContext, ImageBuffer& layerImage, const FloatRect& destRect, const FloatRect& srcRect, const ShadowState& shadowState)
{
if (auto nativeImage = layerImage.copyNativeImage(DontCopyBackingStore)) {
drawPlatformImage(platformContext, nativeImage->platformImage().get(), destRect, srcRect, { shadowState.globalCompositeOperator }, shadowState.globalAlpha, ShadowState());
}
}
static void fillShadowBuffer(GraphicsContextCairo& platformContext, ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize, const ShadowState& shadowState)
{
platformContext.save();
if (auto nativeImage = layerImage.copyNativeImage(DontCopyBackingStore))
clipToImageBuffer(platformContext, nativeImage->platformImage().get(), FloatRect(layerOrigin, expandedIntSize(layerSize)));
FillSource fillSource;
fillSource.globalAlpha = shadowState.globalAlpha;
fillSource.color = shadowState.color;
fillRect(platformContext, FloatRect(layerOrigin, expandedIntSize(layerSize)), fillSource, ShadowState());
platformContext.restore();
}
static inline void drawPathShadow(GraphicsContextCairo& platformContext, const FillSource& fillSource, const StrokeSource& strokeSource, const ShadowState& shadowState, PathDrawingStyle drawingStyle)
{
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
if (shadow.type() == ShadowBlur::NoShadow)
return;
// Calculate the extents of the rendered solid paths.
cairo_t* cairoContext = platformContext.cr();
CairoUniquePtr<cairo_path_t> path(cairo_copy_path(cairoContext));
FloatRect solidFigureExtents;
double x0 = 0;
double x1 = 0;
double y0 = 0;
double y1 = 0;
if (drawingStyle & Stroke) {
cairo_stroke_extents(cairoContext, &x0, &y0, &x1, &y1);
solidFigureExtents = FloatRect(x0, y0, x1 - x0, y1 - y0);
}
if (drawingStyle & Fill) {
cairo_fill_extents(cairoContext, &x0, &y0, &x1, &y1);
FloatRect fillExtents(x0, y0, x1 - x0, y1 - y0);
solidFigureExtents.unite(fillExtents);
}
shadow.drawShadowLayer(State::getCTM(platformContext), State::getClipBounds(platformContext), solidFigureExtents,
[cairoContext, drawingStyle, &path, &fillSource, &strokeSource](GraphicsContext& shadowContext)
{
cairo_t* cairoShadowContext = shadowContext.platformContext()->cr();
// It's important to copy the context properties to the new shadow
// context to preserve things such as the fill rule and stroke width.
copyContextProperties(cairoContext, cairoShadowContext);
if (drawingStyle & Fill) {
cairo_save(cairoShadowContext);
cairo_append_path(cairoShadowContext, path.get());
prepareForFilling(cairoShadowContext, fillSource, NoAdjustment);
cairo_fill(cairoShadowContext);
cairo_restore(cairoShadowContext);
}
if (drawingStyle & Stroke) {
cairo_append_path(cairoShadowContext, path.get());
prepareForStroking(cairoShadowContext, strokeSource, DoNotPreserveAlpha);
cairo_stroke(cairoShadowContext);
}
},
[&platformContext, &shadowState, &cairoContext, &path](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
// The original path may still be hanging around on the context and endShadowLayer
// will take care of properly creating a path to draw the result shadow. We remove the path
// temporarily and then restore it.
// See: https://bugs.webkit.org/show_bug.cgi?id=108897
cairo_new_path(cairoContext);
drawShadowLayerBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
cairo_append_path(cairoContext, path.get());
});
}
static inline void fillCurrentCairoPath(GraphicsContextCairo& platformContext, const FillSource& fillSource)
{
cairo_t* cr = platformContext.cr();
cairo_save(cr);
prepareForFilling(cr, fillSource, AdjustPatternForGlobalAlpha);
cairo_fill(cr);
cairo_restore(cr);
}
static void drawGlyphsToContext(cairo_t* context, cairo_scaled_font_t* scaledFont, double syntheticBoldOffset, const Vector<cairo_glyph_t>& glyphs, FontSmoothingMode fontSmoothingMode)
{
cairo_matrix_t originalTransform;
if (syntheticBoldOffset)
cairo_get_matrix(context, &originalTransform);
cairo_set_scaled_font(context, scaledFont);
// The scaled font defaults to FontSmoothingMode::AutoSmoothing. Only override antialiasing settings if its not auto.
if (fontSmoothingMode != FontSmoothingMode::AutoSmoothing) {
CairoUniquePtr<cairo_font_options_t> fontOptionsSmoothing(cairo_font_options_create());
cairo_scaled_font_get_font_options(scaledFont, fontOptionsSmoothing.get());
switch (fontSmoothingMode) {
case FontSmoothingMode::Antialiased:
// Don't use CAIRO_ANTIALIAS_GRAY in Windows. It is mapped to ANTIALIASED_QUALITY which looks jaggy and faint.
#if !OS(WINDOWS)
cairo_font_options_set_antialias(fontOptionsSmoothing.get(), CAIRO_ANTIALIAS_GRAY);
break;
#endif
case FontSmoothingMode::SubpixelAntialiased:
cairo_font_options_set_antialias(fontOptionsSmoothing.get(), CAIRO_ANTIALIAS_SUBPIXEL);
break;
case FontSmoothingMode::NoSmoothing:
cairo_font_options_set_antialias(fontOptionsSmoothing.get(), CAIRO_ANTIALIAS_NONE);
break;
default:
ASSERT_NOT_REACHED();
}
cairo_set_font_options(context, fontOptionsSmoothing.get());
}
cairo_show_glyphs(context, glyphs.data(), glyphs.size());
if (syntheticBoldOffset) {
cairo_translate(context, syntheticBoldOffset, 0);
cairo_show_glyphs(context, glyphs.data(), glyphs.size());
cairo_set_matrix(context, &originalTransform);
}
}
static void drawGlyphsShadow(GraphicsContextCairo& platformContext, const ShadowState& shadowState, TextDrawingModeFlags textDrawingMode, const FloatSize& shadowOffset, const Color& shadowColor, const FloatPoint& point, cairo_scaled_font_t* scaledFont, double syntheticBoldOffset, const Vector<cairo_glyph_t>& glyphs, FontSmoothingMode fontSmoothingMode)
{
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
if (!textDrawingMode.contains(TextDrawingMode::Fill) || shadow.type() == ShadowBlur::NoShadow)
return;
if (!shadowState.isRequired(platformContext)) {
// Optimize non-blurry shadows, by just drawing text without the ShadowBlur.
cairo_t* context = platformContext.cr();
cairo_save(context);
cairo_translate(context, shadowOffset.width(), shadowOffset.height());
setSourceRGBAFromColor(context, shadowColor);
drawGlyphsToContext(context, scaledFont, syntheticBoldOffset, glyphs, fontSmoothingMode);
cairo_restore(context);
return;
}
cairo_text_extents_t extents;
cairo_scaled_font_glyph_extents(scaledFont, glyphs.data(), glyphs.size(), &extents);
FloatRect fontExtentsRect(point.x() + extents.x_bearing, point.y() + extents.y_bearing, extents.width, extents.height);
shadow.drawShadowLayer(State::getCTM(platformContext), State::getClipBounds(platformContext), fontExtentsRect,
[scaledFont, syntheticBoldOffset, &glyphs, fontSmoothingMode](GraphicsContext& shadowContext)
{
drawGlyphsToContext(shadowContext.platformContext()->cr(), scaledFont, syntheticBoldOffset, glyphs, fontSmoothingMode);
},
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
drawShadowLayerBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
});
}
static bool cairoSurfaceHasAlpha(cairo_surface_t* surface)
{
return cairo_surface_get_content(surface) != CAIRO_CONTENT_COLOR;
}
// FIXME: Fix GraphicsContext::computeLineBoundsAndAntialiasingModeForText()
// to be a static public function that operates on CTM and strokeThickness
// arguments instead of using an underlying GraphicsContext object.
FloatRect computeLineBoundsAndAntialiasingModeForText(GraphicsContextCairo& platformContext, const FloatPoint& point, float width, bool printing, Color& color, float strokeThickness)
{
FloatPoint origin = point;
float thickness = std::max(strokeThickness, 0.5f);
if (printing)
return FloatRect(origin, FloatSize(width, thickness));
AffineTransform transform = Cairo::State::getCTM(platformContext);
// Just compute scale in x dimension, assuming x and y scales are equal.
float scale = transform.b() ? std::hypot(transform.a(), transform.b()) : transform.a();
if (scale < 1.0) {
// This code always draws a line that is at least one-pixel line high,
// which tends to visually overwhelm text at small scales. To counter this
// effect, an alpha is applied to the underline color when text is at small scales.
static const float minimumUnderlineAlpha = 0.4f;
float shade = scale > minimumUnderlineAlpha ? scale : minimumUnderlineAlpha;
color = color.colorWithAlphaMultipliedBy(shade);
}
FloatPoint devicePoint = transform.mapPoint(point);
// Visual overflow might occur here due to integral roundf/ceilf. visualOverflowForDecorations adjusts the overflow value for underline decoration.
FloatPoint deviceOrigin = FloatPoint(roundf(devicePoint.x()), ceilf(devicePoint.y()));
if (auto inverse = transform.inverse())
origin = inverse.value().mapPoint(deviceOrigin);
return FloatRect(origin, FloatSize(width, thickness));
};
// FIXME: Replace once GraphicsContext::dashedLineCornerWidthForStrokeWidth()
// is refactored as a static public function.
static float dashedLineCornerWidthForStrokeWidth(float strokeWidth, StrokeStyle strokeStyle, float strokeThickness)
{
return strokeStyle == DottedStroke ? strokeThickness : std::min(2.0f * strokeThickness, std::max(strokeThickness, strokeWidth / 3.0f));
}
// FIXME: Replace once GraphicsContext::dashedLinePatternWidthForStrokeWidth()
// is refactored as a static public function.
static float dashedLinePatternWidthForStrokeWidth(float strokeWidth, StrokeStyle strokeStyle, float strokeThickness)
{
return strokeStyle == DottedStroke ? strokeThickness : std::min(3.0f * strokeThickness, std::max(strokeThickness, strokeWidth / 3.0f));
}
// FIXME: Replace once GraphicsContext::dashedLinePatternOffsetForPatternAndStrokeWidth()
// is refactored as a static public function.
static float dashedLinePatternOffsetForPatternAndStrokeWidth(float patternWidth, float strokeWidth)
{
// Pattern starts with full fill and ends with the empty fill.
// 1. Let's start with the empty phase after the corner.
// 2. Check if we've got odd or even number of patterns and whether they fully cover the line.
// 3. In case of even number of patterns and/or remainder, move the pattern start position
// so that the pattern is balanced between the corners.
float patternOffset = patternWidth;
int numberOfSegments = std::floor(strokeWidth / patternWidth);
bool oddNumberOfSegments = numberOfSegments % 2;
float remainder = strokeWidth - (numberOfSegments * patternWidth);
if (oddNumberOfSegments && remainder)
patternOffset -= remainder / 2.0f;
else if (!oddNumberOfSegments) {
if (remainder)
patternOffset += patternOffset - (patternWidth + remainder) / 2.0f;
else
patternOffset += patternWidth / 2.0f;
}
return patternOffset;
}
// FIXME: Replace once GraphicsContext::centerLineAndCutOffCorners()
// is refactored as a static public function.
static Vector<FloatPoint> centerLineAndCutOffCorners(bool isVerticalLine, float cornerWidth, FloatPoint point1, FloatPoint point2)
{
// Center line and cut off corners for pattern painting.
if (isVerticalLine) {
float centerOffset = (point2.x() - point1.x()) / 2.0f;
point1.move(centerOffset, cornerWidth);
point2.move(-centerOffset, -cornerWidth);
} else {
float centerOffset = (point2.y() - point1.y()) / 2.0f;
point1.move(cornerWidth, centerOffset);
point2.move(-cornerWidth, -centerOffset);
}
return { point1, point2 };
}
namespace State {
void setStrokeThickness(GraphicsContextCairo& platformContext, float strokeThickness)
{
cairo_set_line_width(platformContext.cr(), strokeThickness);
}
void setStrokeStyle(GraphicsContextCairo& platformContext, StrokeStyle strokeStyle)
{
static const double dashPattern[] = { 5.0, 5.0 };
static const double dotPattern[] = { 1.0, 1.0 };
cairo_t* cr = platformContext.cr();
switch (strokeStyle) {
case NoStroke:
// FIXME: is it the right way to emulate NoStroke?
cairo_set_line_width(cr, 0);
break;
case SolidStroke:
case DoubleStroke:
case WavyStroke:
// FIXME: https://bugs.webkit.org/show_bug.cgi?id=94110 - Needs platform support.
cairo_set_dash(cr, 0, 0, 0);
break;
case DottedStroke:
cairo_set_dash(cr, dotPattern, 2, 0);
break;
case DashedStroke:
cairo_set_dash(cr, dashPattern, 2, 0);
break;
}
}
void setCompositeOperation(GraphicsContextCairo& platformContext, CompositeOperator compositeOperation, BlendMode blendMode)
{
cairo_set_operator(platformContext.cr(), toCairoOperator(compositeOperation, blendMode));
}
void setShouldAntialias(GraphicsContextCairo& platformContext, bool enable)
{
// When true, use the default Cairo backend antialias mode (usually this
// enables standard 'grayscale' antialiasing); false to explicitly disable
// antialiasing.
cairo_set_antialias(platformContext.cr(), enable ? CAIRO_ANTIALIAS_DEFAULT : CAIRO_ANTIALIAS_NONE);
}
void setCTM(GraphicsContextCairo& platformContext, const AffineTransform& transform)
{
const cairo_matrix_t matrix = toCairoMatrix(transform);
cairo_set_matrix(platformContext.cr(), &matrix);
}
AffineTransform getCTM(GraphicsContextCairo& platformContext)
{
cairo_matrix_t m;
cairo_get_matrix(platformContext.cr(), &m);
return AffineTransform(m.xx, m.yx, m.xy, m.yy, m.x0, m.y0);
}
IntRect getClipBounds(GraphicsContextCairo& platformContext)
{
double x1, x2, y1, y2;
cairo_clip_extents(platformContext.cr(), &x1, &y1, &x2, &y2);
return enclosingIntRect(FloatRect(x1, y1, x2 - x1, y2 - y1));
}
FloatRect roundToDevicePixels(GraphicsContextCairo& platformContext, const FloatRect& rect)
{
FloatRect result;
double x = rect.x();
double y = rect.y();
cairo_t* cr = platformContext.cr();
cairo_user_to_device(cr, &x, &y);
x = round(x);
y = round(y);
cairo_device_to_user(cr, &x, &y);
result.setX(narrowPrecisionToFloat(x));
result.setY(narrowPrecisionToFloat(y));
// We must ensure width and height are at least 1 (or -1) when
// we're given float values in the range between 0 and 1 (or -1 and 0).
double width = rect.width();
double height = rect.height();
cairo_user_to_device_distance(cr, &width, &height);
if (width > -1 && width < 0)
width = -1;
else if (width > 0 && width < 1)
width = 1;
else
width = round(width);
if (height > -1 && height < 0)
height = -1;
else if (height > 0 && height < 1)
height = 1;
else
height = round(height);
cairo_device_to_user_distance(cr, &width, &height);
result.setWidth(narrowPrecisionToFloat(width));
result.setHeight(narrowPrecisionToFloat(height));
return result;
}
bool isAcceleratedContext(GraphicsContextCairo& platformContext)
{
return cairo_surface_get_type(cairo_get_target(platformContext.cr())) == CAIRO_SURFACE_TYPE_GL;
}
} // namespace State
FillSource::FillSource(const GraphicsContextState& state)
: globalAlpha(state.alpha)
, fillRule(state.fillRule)
{
if (state.fillPattern) {
pattern.object = adoptRef(state.fillPattern->createPlatformPattern(AffineTransform()));
auto& patternImage = state.fillPattern->tileImage();
pattern.size = patternImage.size();
pattern.transform = state.fillPattern->patternSpaceTransform();
pattern.repeatX = state.fillPattern->repeatX();
pattern.repeatY = state.fillPattern->repeatY();
} else if (state.fillGradient) {
gradient.base = state.fillGradient->createPattern(1, state.fillGradientSpaceTransform);
if (state.alpha != 1)
gradient.alphaAdjusted = state.fillGradient->createPattern(state.alpha, state.fillGradientSpaceTransform);
} else
color = state.fillColor;
}
StrokeSource::StrokeSource(const GraphicsContextState& state)
: globalAlpha(state.alpha)
{
if (state.strokePattern)
pattern = adoptRef(state.strokePattern->createPlatformPattern(AffineTransform()));
else if (state.strokeGradient) {
gradient.base = state.strokeGradient->createPattern(1, state.strokeGradientSpaceTransform);
if (state.alpha != 1)
gradient.alphaAdjusted = state.strokeGradient->createPattern(state.alpha, state.strokeGradientSpaceTransform);
} else
color = state.strokeColor;
}
ShadowState::ShadowState(const GraphicsContextState& state)
: offset(state.shadowOffset)
, blur(state.shadowBlur)
, color(state.shadowColor)
, ignoreTransforms(state.shadowsIgnoreTransforms)
, globalAlpha(state.alpha)
, globalCompositeOperator(state.compositeOperator)
{
}
bool ShadowState::isVisible() const
{
return color.isVisible() && (offset.width() || offset.height() || blur);
}
bool ShadowState::isRequired(GraphicsContextCairo& platformContext) const
{
// We can't avoid ShadowBlur if the shadow has blur.
if (color.isVisible() && blur)
return true;
// We can avoid ShadowBlur and optimize, since we're not drawing on a
// canvas and box shadows are affected by the transformation matrix.
if (!ignoreTransforms)
return false;
// We can avoid ShadowBlur, since there are no transformations to apply to the canvas.
if (State::getCTM(platformContext).isIdentity())
return false;
// Otherwise, no chance avoiding ShadowBlur.
return true;
}
void setLineCap(GraphicsContextCairo& platformContext, LineCap lineCap)
{
cairo_line_cap_t cairoCap { };
switch (lineCap) {
case ButtCap:
cairoCap = CAIRO_LINE_CAP_BUTT;
break;
case RoundCap:
cairoCap = CAIRO_LINE_CAP_ROUND;
break;
case SquareCap:
cairoCap = CAIRO_LINE_CAP_SQUARE;
break;
}
cairo_set_line_cap(platformContext.cr(), cairoCap);
}
void setLineDash(GraphicsContextCairo& platformContext, const DashArray& dashes, float dashOffset)
{
if (std::all_of(dashes.begin(), dashes.end(), [](auto& dash) { return !dash; }))
cairo_set_dash(platformContext.cr(), 0, 0, 0);
else
cairo_set_dash(platformContext.cr(), dashes.data(), dashes.size(), dashOffset);
}
void setLineJoin(GraphicsContextCairo& platformContext, LineJoin lineJoin)
{
cairo_line_join_t cairoJoin { };
switch (lineJoin) {
case MiterJoin:
cairoJoin = CAIRO_LINE_JOIN_MITER;
break;
case RoundJoin:
cairoJoin = CAIRO_LINE_JOIN_ROUND;
break;
case BevelJoin:
cairoJoin = CAIRO_LINE_JOIN_BEVEL;
break;
}
cairo_set_line_join(platformContext.cr(), cairoJoin);
}
void setMiterLimit(GraphicsContextCairo& platformContext, float miterLimit)
{
cairo_set_miter_limit(platformContext.cr(), miterLimit);
}
void fillRect(GraphicsContextCairo& platformContext, const FloatRect& rect, const FillSource& fillSource, const ShadowState& shadowState)
{
cairo_t* cr = platformContext.cr();
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
drawPathShadow(platformContext, fillSource, { }, shadowState, Fill);
fillCurrentCairoPath(platformContext, fillSource);
}
void fillRect(GraphicsContextCairo& platformContext, const FloatRect& rect, const Color& color, const ShadowState& shadowState)
{
if (shadowState.isVisible()) {
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
shadow.drawRectShadow(State::getCTM(platformContext), State::getClipBounds(platformContext), FloatRoundedRect(rect),
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
fillShadowBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
},
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatRect& destRect, const FloatRect& srcRect)
{
drawShadowImage(platformContext, layerImage, destRect, srcRect, shadowState);
},
[&platformContext](const FloatRect& rect, const Color& color)
{
fillRectWithColor(platformContext.cr(), rect, color);
});
}
fillRectWithColor(platformContext.cr(), rect, color);
}
void fillRect(GraphicsContextCairo& platformContext, const FloatRect& rect, cairo_pattern_t* platformPattern)
{
cairo_t* cr = platformContext.cr();
cairo_set_source(cr, platformPattern);
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
cairo_fill(cr);
}
void fillRoundedRect(GraphicsContextCairo& platformContext, const FloatRoundedRect& rect, const Color& color, const ShadowState& shadowState)
{
if (shadowState.isVisible()) {
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
shadow.drawRectShadow(State::getCTM(platformContext), State::getClipBounds(platformContext), rect,
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
fillShadowBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
},
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatRect& destRect, const FloatRect& srcRect)
{
drawShadowImage(platformContext, layerImage, destRect, srcRect, shadowState);
},
[&platformContext](const FloatRect& rect, const Color& color)
{
fillRectWithColor(platformContext.cr(), rect, color);
});
}
cairo_t* cr = platformContext.cr();
cairo_save(cr);
Path path;
path.addRoundedRect(rect);
appendWebCorePathToCairoContext(cr, path);
setSourceRGBAFromColor(cr, color);
cairo_fill(cr);
cairo_restore(cr);
}
void fillRectWithRoundedHole(GraphicsContextCairo& platformContext, const FloatRect& rect, const FloatRoundedRect& roundedHoleRect, const FillSource& fillSource, const ShadowState& shadowState)
{
// FIXME: this should leverage the specified color.
if (shadowState.isVisible()) {
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
shadow.drawInsetShadow(State::getCTM(platformContext), State::getClipBounds(platformContext), rect, roundedHoleRect,
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
fillShadowBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
},
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatRect& destRect, const FloatRect& srcRect)
{
drawShadowImage(platformContext, layerImage, destRect, srcRect, shadowState);
},
[&platformContext](const FloatRect& rect, const FloatRect& holeRect, const Color& color)
{
// FIXME: We should use fillRectWithRoundedHole.
cairo_t* cr = platformContext.cr();
cairo_save(cr);
setSourceRGBAFromColor(cr, color);
cairo_set_fill_rule(cr, CAIRO_FILL_RULE_EVEN_ODD);
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
cairo_rectangle(cr, holeRect.x(), holeRect.y(), holeRect.width(), holeRect.height());
cairo_fill(cr);
cairo_restore(cr);
});
}
Path path;
path.addRect(rect);
if (!roundedHoleRect.radii().isZero())
path.addRoundedRect(roundedHoleRect);
else
path.addRect(roundedHoleRect.rect());
cairo_t* cr = platformContext.cr();
cairo_save(cr);
setPathOnCairoContext(platformContext.cr(), path.cairoPath());
fillCurrentCairoPath(platformContext, fillSource);
cairo_restore(cr);
}
void fillPath(GraphicsContextCairo& platformContext, const Path& path, const FillSource& fillSource, const ShadowState& shadowState)
{
cairo_t* cr = platformContext.cr();
setPathOnCairoContext(cr, path.cairoPath());
drawPathShadow(platformContext, fillSource, { }, shadowState, Fill);
fillCurrentCairoPath(platformContext, fillSource);
}
void strokeRect(GraphicsContextCairo& platformContext, const FloatRect& rect, float lineWidth, const StrokeSource& strokeSource, const ShadowState& shadowState)
{
cairo_t* cr = platformContext.cr();
cairo_save(cr);
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
cairo_set_line_width(cr, lineWidth);
drawPathShadow(platformContext, { }, strokeSource, shadowState, Stroke);
prepareForStroking(cr, strokeSource, PreserveAlpha);
cairo_stroke(cr);
cairo_restore(cr);
}
void strokePath(GraphicsContextCairo& platformContext, const Path& path, const StrokeSource& strokeSource, const ShadowState& shadowState)
{
cairo_t* cr = platformContext.cr();
setPathOnCairoContext(cr, path.cairoPath());
drawPathShadow(platformContext, { }, strokeSource, shadowState, Stroke);
prepareForStroking(cr, strokeSource, PreserveAlpha);
cairo_stroke(cr);
}
void clearRect(GraphicsContextCairo& platformContext, const FloatRect& rect)
{
cairo_t* cr = platformContext.cr();
cairo_save(cr);
cairo_rectangle(cr, rect.x(), rect.y(), rect.width(), rect.height());
cairo_set_operator(cr, CAIRO_OPERATOR_CLEAR);
cairo_fill(cr);
cairo_restore(cr);
}
void drawGlyphs(GraphicsContextCairo& platformContext, const FillSource& fillSource, const StrokeSource& strokeSource, const ShadowState& shadowState, const FloatPoint& point, cairo_scaled_font_t* scaledFont, double syntheticBoldOffset, const Vector<cairo_glyph_t>& glyphs, float xOffset, TextDrawingModeFlags textDrawingMode, float strokeThickness, const FloatSize& shadowOffset, const Color& shadowColor, FontSmoothingMode fontSmoothingMode)
{
drawGlyphsShadow(platformContext, shadowState, textDrawingMode, shadowOffset, shadowColor, point, scaledFont, syntheticBoldOffset, glyphs, fontSmoothingMode);
cairo_t* cr = platformContext.cr();
cairo_save(cr);
if (textDrawingMode.contains(TextDrawingMode::Fill)) {
prepareForFilling(cr, fillSource, AdjustPatternForGlobalAlpha);
drawGlyphsToContext(cr, scaledFont, syntheticBoldOffset, glyphs, fontSmoothingMode);
}
// Prevent running into a long computation within cairo. If the stroke width is
// twice the size of the width of the text we will not ask cairo to stroke
// the text as even one single stroke would cover the full wdth of the text.
// See https://bugs.webkit.org/show_bug.cgi?id=33759.
if (textDrawingMode.contains(TextDrawingMode::Stroke) && strokeThickness < 2 * xOffset) {
prepareForStroking(cr, strokeSource, PreserveAlpha);
cairo_set_line_width(cr, strokeThickness);
// This may disturb the CTM, but we are going to call cairo_restore soon after.
cairo_set_scaled_font(cr, scaledFont);
cairo_glyph_path(cr, glyphs.data(), glyphs.size());
cairo_stroke(cr);
}
cairo_restore(cr);
}
void drawPlatformImage(GraphicsContextCairo& platformContext, cairo_surface_t* surface, const FloatRect& destRect, const FloatRect& srcRect, const ImagePaintingOptions& options, float globalAlpha, const ShadowState& shadowState)
{
platformContext.save();
// Set the compositing operation.
if (options.compositeOperator() == CompositeOperator::SourceOver && options.blendMode() == BlendMode::Normal && !cairoSurfaceHasAlpha(surface))
Cairo::State::setCompositeOperation(platformContext, CompositeOperator::Copy, BlendMode::Normal);
else
Cairo::State::setCompositeOperation(platformContext, options.compositeOperator(), options.blendMode());
FloatRect dst = destRect;
if (options.orientation() != ImageOrientation::None) {
// ImageOrientation expects the origin to be at (0, 0).
Cairo::translate(platformContext, dst.x(), dst.y());
dst.setLocation(FloatPoint());
Cairo::concatCTM(platformContext, options.orientation().transformFromDefault(dst.size()));
if (options.orientation().usesWidthAsHeight()) {
// The destination rectangle will have its width and height already reversed for the orientation of
// the image, as it was needed for page layout, so we need to reverse it back here.
dst = FloatRect(dst.x(), dst.y(), dst.height(), dst.width());
}
}
auto orientationSizing = options.orientation().usesWidthAsHeight() ? OrientationSizing::WidthAsHeight : OrientationSizing::Normal;
drawSurface(platformContext, surface, dst, srcRect, options.interpolationQuality(), globalAlpha, shadowState, orientationSizing);
platformContext.restore();
}
void drawPattern(GraphicsContextCairo& platformContext, cairo_surface_t* surface, const IntSize& size, const FloatRect& destRect, const FloatRect& tileRect, const AffineTransform& patternTransform, const FloatPoint& phase, const ImagePaintingOptions& options)
{
// FIXME: Investigate why the size has to be passed in as an IntRect.
drawPatternToCairoContext(platformContext.cr(), surface, size, tileRect, patternTransform, phase, toCairoOperator(options.compositeOperator(), options.blendMode()), options.interpolationQuality(), destRect);
}
void drawSurface(GraphicsContextCairo& platformContext, cairo_surface_t* surface, const FloatRect& destRect, const FloatRect& originalSrcRect, InterpolationQuality imageInterpolationQuality, float globalAlpha, const ShadowState& shadowState, OrientationSizing orientationSizing)
{
// Avoid invalid cairo matrix with small values.
if (std::fabs(destRect.width()) < 0.5f || std::fabs(destRect.height()) < 0.5f)
return;
FloatRect srcRect = originalSrcRect;
// We need to account for negative source dimensions by flipping the rectangle.
if (originalSrcRect.width() < 0) {
srcRect.setX(originalSrcRect.x() + originalSrcRect.width());
srcRect.setWidth(std::fabs(originalSrcRect.width()));
}
if (originalSrcRect.height() < 0) {
srcRect.setY(originalSrcRect.y() + originalSrcRect.height());
srcRect.setHeight(std::fabs(originalSrcRect.height()));
}
RefPtr<cairo_surface_t> patternSurface = surface;
float leftPadding = 0;
float topPadding = 0;
auto surfaceSize = cairoSurfaceSize(surface);
bool didUseWidthAsHeight = orientationSizing == OrientationSizing::WidthAsHeight;
bool differentSize = srcRect.size() != (didUseWidthAsHeight ? surfaceSize.transposedSize() : surfaceSize);
if (srcRect.x() || srcRect.y() || differentSize) {
// Cairo subsurfaces don't support floating point boundaries well, so we expand the rectangle.
IntRect expandedSrcRect(enclosingIntRect(srcRect));
expandedSrcRect.intersect({ { }, cairoSurfaceSize(surface) });
// We use a subsurface here so that we don't end up sampling outside the originalSrcRect rectangle.
// See https://bugs.webkit.org/show_bug.cgi?id=58309
patternSurface = adoptRef(cairo_surface_create_for_rectangle(surface, expandedSrcRect.x(),
expandedSrcRect.y(), expandedSrcRect.width(), expandedSrcRect.height()));
leftPadding = static_cast<float>(expandedSrcRect.x()) - floorf(srcRect.x());
topPadding = static_cast<float>(expandedSrcRect.y()) - floorf(srcRect.y());
}
RefPtr<cairo_pattern_t> pattern = adoptRef(cairo_pattern_create_for_surface(patternSurface.get()));
switch (imageInterpolationQuality) {
case InterpolationQuality::DoNotInterpolate:
case InterpolationQuality::Low:
cairo_pattern_set_filter(pattern.get(), CAIRO_FILTER_FAST);
break;
case InterpolationQuality::Medium:
case InterpolationQuality::Default:
cairo_pattern_set_filter(pattern.get(), CAIRO_FILTER_GOOD);
break;
case InterpolationQuality::High:
cairo_pattern_set_filter(pattern.get(), CAIRO_FILTER_BEST);
break;
}
cairo_pattern_set_extend(pattern.get(), CAIRO_EXTEND_PAD);
// The pattern transformation properly scales the pattern for when the source rectangle is a
// different size than the destination rectangle. We also account for any offset we introduced
// by expanding floating point source rectangle sizes. It's important to take the absolute value
// of the scale since the original width and height might be negative.
float scaleX = 1;
float scaleY = 1;
if (didUseWidthAsHeight) {
scaleX = std::fabs(srcRect.width() / destRect.height());
scaleY = std::fabs(srcRect.height() / destRect.width());
} else {
scaleX = std::fabs(srcRect.width() / destRect.width());
scaleY = std::fabs(srcRect.height() / destRect.height());
}
cairo_matrix_t matrix = { scaleX, 0, 0, scaleY, leftPadding, topPadding };
cairo_pattern_set_matrix(pattern.get(), &matrix);
ShadowBlur shadow({ shadowState.blur, shadowState.blur }, shadowState.offset, shadowState.color, shadowState.ignoreTransforms);
if (shadow.type() != ShadowBlur::NoShadow) {
shadow.drawShadowLayer(State::getCTM(platformContext), State::getClipBounds(platformContext), destRect,
[&pattern, &destRect](GraphicsContext& shadowContext)
{
drawPatternToCairoContext(shadowContext.platformContext()->cr(), pattern.get(), destRect, 1);
},
[&platformContext, &shadowState](ImageBuffer& layerImage, const FloatPoint& layerOrigin, const FloatSize& layerSize)
{
drawShadowLayerBuffer(platformContext, layerImage, layerOrigin, layerSize, shadowState);
});
}
auto* cr = platformContext.cr();
cairo_save(cr);
drawPatternToCairoContext(cr, pattern.get(), destRect, globalAlpha);
cairo_restore(cr);
}
void drawRect(GraphicsContextCairo& platformContext, const FloatRect& rect, float borderThickness, const Color& fillColor, StrokeStyle strokeStyle, const Color& strokeColor)
{
// FIXME: how should borderThickness be used?
UNUSED_PARAM(borderThickness);
cairo_t* cr = platformContext.cr();
cairo_save(cr);
fillRectWithColor(cr, rect, fillColor);
if (strokeStyle != NoStroke) {
setSourceRGBAFromColor(cr, strokeColor);
FloatRect r(rect);
r.inflate(-.5f);
cairo_rectangle(cr, r.x(), r.y(), r.width(), r.height());
cairo_set_line_width(cr, 1.0); // borderThickness?
cairo_stroke(cr);