blob: 2e3f82919520d7f79818c63f37a88e79a38bc9a2 [file] [log] [blame]
/*
* Copyright (C) 2003, 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
* Copyright (C) 2008 Eric Seidel <eric@webkit.org>
*
* 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 COMPUTER, 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 COMPUTER, 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.
*/
#define _USE_MATH_DEFINES 1
#include "config.h"
#include "GraphicsContext.h"
#include "AffineTransform.h"
#include "FloatConversion.h"
#include "GraphicsContextPlatformPrivateCG.h"
#include "GraphicsContextPrivate.h"
#include "ImageBuffer.h"
#include "KURL.h"
#include "Path.h"
#include "Pattern.h"
#include <CoreGraphics/CGBitmapContext.h>
#include <CoreGraphics/CGPDFContext.h>
#include <wtf/MathExtras.h>
#include <wtf/OwnArrayPtr.h>
#include <wtf/RetainPtr.h>
#if PLATFORM(MAC) || PLATFORM(CHROMIUM)
#include "WebCoreSystemInterface.h"
#endif
#if PLATFORM(WIN)
#include <WebKitSystemInterface/WebKitSystemInterface.h>
#endif
#if PLATFORM(MAC) || (PLATFORM(CHROMIUM) && OS(DARWIN))
#if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD)
// Building on 10.6 or later: kCGInterpolationMedium is defined in the CGInterpolationQuality enum.
#define HAVE_CG_INTERPOLATION_MEDIUM 1
#endif
#if !defined(TARGETING_TIGER) && !defined(TARGETING_LEOPARD)
// Targeting 10.6 or later: use kCGInterpolationMedium.
#define WTF_USE_CG_INTERPOLATION_MEDIUM 1
#endif
#endif
using namespace std;
namespace WebCore {
static CGColorRef createCGColorWithColorSpace(const Color& color, ColorSpace colorSpace)
{
CGFloat components[4];
color.getRGBA(components[0], components[1], components[2], components[3]);
CGColorRef cgColor = 0;
if (colorSpace == sRGBColorSpace)
cgColor = CGColorCreate(sRGBColorSpaceRef(), components);
else
cgColor = CGColorCreate(deviceRGBColorSpaceRef(), components);
return cgColor;
}
static void setCGFillColor(CGContextRef context, const Color& color, ColorSpace colorSpace)
{
CGColorRef cgColor = createCGColorWithColorSpace(color, colorSpace);
CGContextSetFillColorWithColor(context, cgColor);
CFRelease(cgColor);
}
static void setCGStrokeColor(CGContextRef context, const Color& color, ColorSpace colorSpace)
{
CGColorRef cgColor = createCGColorWithColorSpace(color, colorSpace);
CGContextSetStrokeColorWithColor(context, cgColor);
CFRelease(cgColor);
}
static void setCGFillColorSpace(CGContextRef context, ColorSpace colorSpace)
{
switch (colorSpace) {
case DeviceColorSpace:
break;
case sRGBColorSpace:
CGContextSetFillColorSpace(context, sRGBColorSpaceRef());
break;
default:
ASSERT_NOT_REACHED();
break;
}
}
static void setCGStrokeColorSpace(CGContextRef context, ColorSpace colorSpace)
{
switch (colorSpace) {
case DeviceColorSpace:
break;
case sRGBColorSpace:
CGContextSetStrokeColorSpace(context, sRGBColorSpaceRef());
break;
default:
ASSERT_NOT_REACHED();
break;
}
}
CGColorSpaceRef deviceRGBColorSpaceRef()
{
static CGColorSpaceRef deviceSpace = CGColorSpaceCreateDeviceRGB();
return deviceSpace;
}
CGColorSpaceRef sRGBColorSpaceRef()
{
// FIXME: Windows should be able to use kCGColorSpaceSRGB, this is tracked by http://webkit.org/b/31363.
#if PLATFORM(WIN) || defined(BUILDING_ON_TIGER)
return deviceRGBColorSpaceRef();
#else
static CGColorSpaceRef sRGBSpace = CGColorSpaceCreateWithName(kCGColorSpaceSRGB);
return sRGBSpace;
#endif
}
GraphicsContext::GraphicsContext(CGContextRef cgContext)
: m_common(createGraphicsContextPrivate())
, m_data(new GraphicsContextPlatformPrivate(cgContext))
{
setPaintingDisabled(!cgContext);
if (cgContext) {
// Make sure the context starts in sync with our state.
setPlatformFillColor(fillColor(), fillColorSpace());
setPlatformStrokeColor(strokeColor(), strokeColorSpace());
}
}
GraphicsContext::~GraphicsContext()
{
destroyGraphicsContextPrivate(m_common);
delete m_data;
}
CGContextRef GraphicsContext::platformContext() const
{
ASSERT(!paintingDisabled());
ASSERT(m_data->m_cgContext);
return m_data->m_cgContext.get();
}
void GraphicsContext::savePlatformState()
{
// Note: Do not use this function within this class implementation, since we want to avoid the extra
// save of the secondary context (in GraphicsContextPlatformPrivateCG.h).
CGContextSaveGState(platformContext());
m_data->save();
}
void GraphicsContext::restorePlatformState()
{
// Note: Do not use this function within this class implementation, since we want to avoid the extra
// restore of the secondary context (in GraphicsContextPlatformPrivateCG.h).
CGContextRestoreGState(platformContext());
m_data->restore();
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
// Draws a filled rectangle with a stroked border.
void GraphicsContext::drawRect(const IntRect& rect)
{
// FIXME: this function does not handle patterns and gradients
// like drawPath does, it probably should.
if (paintingDisabled())
return;
CGContextRef context = platformContext();
CGContextFillRect(context, rect);
if (strokeStyle() != NoStroke) {
// We do a fill of four rects to simulate the stroke of a border.
Color oldFillColor = fillColor();
if (oldFillColor != strokeColor())
setCGFillColor(context, strokeColor(), strokeColorSpace());
CGRect rects[4] = {
FloatRect(rect.x(), rect.y(), rect.width(), 1),
FloatRect(rect.x(), rect.bottom() - 1, rect.width(), 1),
FloatRect(rect.x(), rect.y() + 1, 1, rect.height() - 2),
FloatRect(rect.right() - 1, rect.y() + 1, 1, rect.height() - 2)
};
CGContextFillRects(context, rects, 4);
if (oldFillColor != strokeColor())
setCGFillColor(context, oldFillColor, fillColorSpace());
}
}
// This is only used to draw borders.
void GraphicsContext::drawLine(const IntPoint& point1, const IntPoint& point2)
{
if (paintingDisabled())
return;
if (strokeStyle() == NoStroke)
return;
float width = strokeThickness();
FloatPoint p1 = point1;
FloatPoint p2 = point2;
bool isVerticalLine = (p1.x() == p2.x());
// For odd widths, we add in 0.5 to the appropriate x/y so that the float arithmetic
// works out. For example, with a border width of 3, KHTML will pass us (y1+y2)/2, e.g.,
// (50+53)/2 = 103/2 = 51 when we want 51.5. It is always true that an even width gave
// us a perfect position, but an odd width gave us a position that is off by exactly 0.5.
if (strokeStyle() == DottedStroke || strokeStyle() == DashedStroke) {
if (isVerticalLine) {
p1.move(0, width);
p2.move(0, -width);
} else {
p1.move(width, 0);
p2.move(-width, 0);
}
}
if (((int)width) % 2) {
if (isVerticalLine) {
// We're a vertical line. Adjust our x.
p1.move(0.5f, 0.0f);
p2.move(0.5f, 0.0f);
} else {
// We're a horizontal line. Adjust our y.
p1.move(0.0f, 0.5f);
p2.move(0.0f, 0.5f);
}
}
int patWidth = 0;
switch (strokeStyle()) {
case NoStroke:
case SolidStroke:
break;
case DottedStroke:
patWidth = (int)width;
break;
case DashedStroke:
patWidth = 3 * (int)width;
break;
}
CGContextRef context = platformContext();
if (shouldAntialias())
CGContextSetShouldAntialias(context, false);
if (patWidth) {
CGContextSaveGState(context);
// Do a rect fill of our endpoints. This ensures we always have the
// appearance of being a border. We then draw the actual dotted/dashed line.
setCGFillColor(context, strokeColor(), strokeColorSpace()); // The save/restore make it safe to mutate the fill color here without setting it back to the old color.
if (isVerticalLine) {
CGContextFillRect(context, FloatRect(p1.x() - width / 2, p1.y() - width, width, width));
CGContextFillRect(context, FloatRect(p2.x() - width / 2, p2.y(), width, width));
} else {
CGContextFillRect(context, FloatRect(p1.x() - width, p1.y() - width / 2, width, width));
CGContextFillRect(context, FloatRect(p2.x(), p2.y() - width / 2, width, width));
}
// Example: 80 pixels with a width of 30 pixels.
// Remainder is 20. The maximum pixels of line we could paint
// will be 50 pixels.
int distance = (isVerticalLine ? (point2.y() - point1.y()) : (point2.x() - point1.x())) - 2*(int)width;
int remainder = distance % patWidth;
int coverage = distance - remainder;
int numSegments = coverage / patWidth;
float patternOffset = 0.0f;
// Special case 1px dotted borders for speed.
if (patWidth == 1)
patternOffset = 1.0f;
else {
bool evenNumberOfSegments = !(numSegments % 2);
if (remainder)
evenNumberOfSegments = !evenNumberOfSegments;
if (evenNumberOfSegments) {
if (remainder) {
patternOffset += patWidth - remainder;
patternOffset += remainder / 2;
} else
patternOffset = patWidth / 2;
} else {
if (remainder)
patternOffset = (patWidth - remainder)/2;
}
}
const CGFloat dottedLine[2] = { patWidth, patWidth };
CGContextSetLineDash(context, patternOffset, dottedLine, 2);
}
CGContextBeginPath(context);
CGContextMoveToPoint(context, p1.x(), p1.y());
CGContextAddLineToPoint(context, p2.x(), p2.y());
CGContextStrokePath(context);
if (patWidth)
CGContextRestoreGState(context);
if (shouldAntialias())
CGContextSetShouldAntialias(context, true);
}
// This method is only used to draw the little circles used in lists.
void GraphicsContext::drawEllipse(const IntRect& rect)
{
// FIXME: CG added CGContextAddEllipseinRect in Tiger, so we should be able to quite easily draw an ellipse.
// This code can only handle circles, not ellipses. But khtml only
// uses it for circles.
ASSERT(rect.width() == rect.height());
if (paintingDisabled())
return;
CGContextRef context = platformContext();
CGContextBeginPath(context);
float r = (float)rect.width() / 2;
CGContextAddArc(context, rect.x() + r, rect.y() + r, r, 0.0f, 2.0f * piFloat, 0);
CGContextClosePath(context);
drawPath();
}
void GraphicsContext::strokeArc(const IntRect& rect, int startAngle, int angleSpan)
{
if (paintingDisabled() || strokeStyle() == NoStroke || strokeThickness() <= 0.0f)
return;
CGContextRef context = platformContext();
CGContextSaveGState(context);
CGContextBeginPath(context);
CGContextSetShouldAntialias(context, false);
int x = rect.x();
int y = rect.y();
float w = (float)rect.width();
float h = (float)rect.height();
float scaleFactor = h / w;
float reverseScaleFactor = w / h;
if (w != h)
scale(FloatSize(1, scaleFactor));
float hRadius = w / 2;
float vRadius = h / 2;
float fa = startAngle;
float falen = fa + angleSpan;
float start = -fa * piFloat / 180.0f;
float end = -falen * piFloat / 180.0f;
CGContextAddArc(context, x + hRadius, (y + vRadius) * reverseScaleFactor, hRadius, start, end, true);
if (w != h)
scale(FloatSize(1, reverseScaleFactor));
float width = strokeThickness();
int patWidth = 0;
switch (strokeStyle()) {
case DottedStroke:
patWidth = (int)(width / 2);
break;
case DashedStroke:
patWidth = 3 * (int)(width / 2);
break;
default:
break;
}
if (patWidth) {
// Example: 80 pixels with a width of 30 pixels.
// Remainder is 20. The maximum pixels of line we could paint
// will be 50 pixels.
int distance;
if (hRadius == vRadius)
distance = static_cast<int>((piFloat * hRadius) / 2.0f);
else // We are elliptical and will have to estimate the distance
distance = static_cast<int>((piFloat * sqrtf((hRadius * hRadius + vRadius * vRadius) / 2.0f)) / 2.0f);
int remainder = distance % patWidth;
int coverage = distance - remainder;
int numSegments = coverage / patWidth;
float patternOffset = 0.0f;
// Special case 1px dotted borders for speed.
if (patWidth == 1)
patternOffset = 1.0f;
else {
bool evenNumberOfSegments = !(numSegments % 2);
if (remainder)
evenNumberOfSegments = !evenNumberOfSegments;
if (evenNumberOfSegments) {
if (remainder) {
patternOffset += patWidth - remainder;
patternOffset += remainder / 2.0f;
} else
patternOffset = patWidth / 2.0f;
} else {
if (remainder)
patternOffset = (patWidth - remainder) / 2.0f;
}
}
const CGFloat dottedLine[2] = { patWidth, patWidth };
CGContextSetLineDash(context, patternOffset, dottedLine, 2);
}
CGContextStrokePath(context);
CGContextRestoreGState(context);
}
void GraphicsContext::drawConvexPolygon(size_t npoints, const FloatPoint* points, bool antialiased)
{
if (paintingDisabled())
return;
if (npoints <= 1)
return;
CGContextRef context = platformContext();
if (antialiased != shouldAntialias())
CGContextSetShouldAntialias(context, antialiased);
CGContextBeginPath(context);
CGContextMoveToPoint(context, points[0].x(), points[0].y());
for (size_t i = 1; i < npoints; i++)
CGContextAddLineToPoint(context, points[i].x(), points[i].y());
CGContextClosePath(context);
drawPath();
if (antialiased != shouldAntialias())
CGContextSetShouldAntialias(context, shouldAntialias());
}
void GraphicsContext::applyStrokePattern()
{
CGContextRef cgContext = platformContext();
RetainPtr<CGPatternRef> platformPattern(AdoptCF, m_common->state.strokePattern->createPlatformPattern(getCTM()));
if (!platformPattern)
return;
RetainPtr<CGColorSpaceRef> patternSpace(AdoptCF, CGColorSpaceCreatePattern(0));
CGContextSetStrokeColorSpace(cgContext, patternSpace.get());
const CGFloat patternAlpha = 1;
CGContextSetStrokePattern(cgContext, platformPattern.get(), &patternAlpha);
}
void GraphicsContext::applyFillPattern()
{
CGContextRef cgContext = platformContext();
RetainPtr<CGPatternRef> platformPattern(AdoptCF, m_common->state.fillPattern->createPlatformPattern(getCTM()));
if (!platformPattern)
return;
RetainPtr<CGColorSpaceRef> patternSpace(AdoptCF, CGColorSpaceCreatePattern(0));
CGContextSetFillColorSpace(cgContext, patternSpace.get());
const CGFloat patternAlpha = 1;
CGContextSetFillPattern(cgContext, platformPattern.get(), &patternAlpha);
}
static inline bool calculateDrawingMode(const GraphicsContextState& state, CGPathDrawingMode& mode)
{
bool shouldFill = state.fillPattern || state.fillColor.alpha();
bool shouldStroke = state.strokePattern || (state.strokeStyle != NoStroke && state.strokeColor.alpha());
bool useEOFill = state.fillRule == RULE_EVENODD;
if (shouldFill) {
if (shouldStroke) {
if (useEOFill)
mode = kCGPathEOFillStroke;
else
mode = kCGPathFillStroke;
} else { // fill, no stroke
if (useEOFill)
mode = kCGPathEOFill;
else
mode = kCGPathFill;
}
} else {
// Setting mode to kCGPathStroke even if shouldStroke is false. In that case, we return false and mode will not be used,
// but the compiler will not complain about an uninitialized variable.
mode = kCGPathStroke;
}
return shouldFill || shouldStroke;
}
void GraphicsContext::drawPath()
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
const GraphicsContextState& state = m_common->state;
if (state.fillGradient || state.strokeGradient) {
// We don't have any optimized way to fill & stroke a path using gradients
fillPath();
strokePath();
return;
}
if (state.fillPattern)
applyFillPattern();
if (state.strokePattern)
applyStrokePattern();
CGPathDrawingMode drawingMode;
if (calculateDrawingMode(state, drawingMode))
CGContextDrawPath(context, drawingMode);
}
static inline void fillPathWithFillRule(CGContextRef context, WindRule fillRule)
{
if (fillRule == RULE_EVENODD)
CGContextEOFillPath(context);
else
CGContextFillPath(context);
}
void GraphicsContext::fillPath()
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
// FIXME: Is this helpful and correct in the fillPattern and fillGradient cases?
setCGFillColorSpace(context, m_common->state.fillColorSpace);
if (m_common->state.fillGradient) {
CGContextSaveGState(context);
if (fillRule() == RULE_EVENODD)
CGContextEOClip(context);
else
CGContextClip(context);
CGContextConcatCTM(context, m_common->state.fillGradient->gradientSpaceTransform());
m_common->state.fillGradient->paint(this);
CGContextRestoreGState(context);
return;
}
if (m_common->state.fillPattern)
applyFillPattern();
fillPathWithFillRule(context, fillRule());
}
void GraphicsContext::strokePath()
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
// FIXME: Is this helpful and correct in the strokePattern and strokeGradient cases?
setCGStrokeColorSpace(context, m_common->state.strokeColorSpace);
if (m_common->state.strokeGradient) {
CGContextSaveGState(context);
CGContextReplacePathWithStrokedPath(context);
CGContextClip(context);
CGContextConcatCTM(context, m_common->state.strokeGradient->gradientSpaceTransform());
m_common->state.strokeGradient->paint(this);
CGContextRestoreGState(context);
return;
}
if (m_common->state.strokePattern)
applyStrokePattern();
CGContextStrokePath(context);
}
void GraphicsContext::fillRect(const FloatRect& rect)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
// FIXME: Is this helpful and correct in the fillPattern and fillGradient cases?
setCGFillColorSpace(context, m_common->state.fillColorSpace);
if (m_common->state.fillGradient) {
CGContextSaveGState(context);
CGContextClipToRect(context, rect);
CGContextConcatCTM(context, m_common->state.fillGradient->gradientSpaceTransform());
m_common->state.fillGradient->paint(this);
CGContextRestoreGState(context);
return;
}
if (m_common->state.fillPattern)
applyFillPattern();
CGContextFillRect(context, rect);
}
void GraphicsContext::fillRect(const FloatRect& rect, const Color& color, ColorSpace colorSpace)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
Color oldFillColor = fillColor();
ColorSpace oldColorSpace = fillColorSpace();
if (oldFillColor != color || oldColorSpace != colorSpace)
setCGFillColor(context, color, colorSpace);
CGContextFillRect(context, rect);
if (oldFillColor != color || oldColorSpace != colorSpace)
setCGFillColor(context, oldFillColor, oldColorSpace);
}
void GraphicsContext::fillRoundedRect(const IntRect& rect, const IntSize& topLeft, const IntSize& topRight, const IntSize& bottomLeft, const IntSize& bottomRight, const Color& color, ColorSpace colorSpace)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
Color oldFillColor = fillColor();
ColorSpace oldColorSpace = fillColorSpace();
if (oldFillColor != color || oldColorSpace != colorSpace)
setCGFillColor(context, color, colorSpace);
addPath(Path::createRoundedRectangle(rect, topLeft, topRight, bottomLeft, bottomRight));
fillPath();
if (oldFillColor != color || oldColorSpace != colorSpace)
setCGFillColor(context, oldFillColor, oldColorSpace);
}
void GraphicsContext::clip(const FloatRect& rect)
{
if (paintingDisabled())
return;
CGContextClipToRect(platformContext(), rect);
m_data->clip(rect);
}
void GraphicsContext::clipOut(const IntRect& rect)
{
if (paintingDisabled())
return;
CGRect rects[2] = { CGContextGetClipBoundingBox(platformContext()), rect };
CGContextBeginPath(platformContext());
CGContextAddRects(platformContext(), rects, 2);
CGContextEOClip(platformContext());
}
void GraphicsContext::clipOutEllipseInRect(const IntRect& rect)
{
if (paintingDisabled())
return;
CGContextBeginPath(platformContext());
CGContextAddRect(platformContext(), CGContextGetClipBoundingBox(platformContext()));
CGContextAddEllipseInRect(platformContext(), rect);
CGContextEOClip(platformContext());
}
void GraphicsContext::clipPath(WindRule clipRule)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
if (!CGContextIsPathEmpty(context)) {
if (clipRule == RULE_EVENODD)
CGContextEOClip(context);
else
CGContextClip(context);
}
}
void GraphicsContext::addInnerRoundedRectClip(const IntRect& rect, int thickness)
{
if (paintingDisabled())
return;
clip(rect);
CGContextRef context = platformContext();
// Add outer ellipse
CGContextAddEllipseInRect(context, CGRectMake(rect.x(), rect.y(), rect.width(), rect.height()));
// Add inner ellipse.
CGContextAddEllipseInRect(context, CGRectMake(rect.x() + thickness, rect.y() + thickness,
rect.width() - (thickness * 2), rect.height() - (thickness * 2)));
CGContextEOClip(context);
}
void GraphicsContext::clipToImageBuffer(const FloatRect& rect, const ImageBuffer* imageBuffer)
{
if (paintingDisabled())
return;
CGContextTranslateCTM(platformContext(), rect.x(), rect.y() + rect.height());
CGContextScaleCTM(platformContext(), 1, -1);
CGContextClipToMask(platformContext(), FloatRect(FloatPoint(), rect.size()), imageBuffer->image()->getCGImageRef());
CGContextScaleCTM(platformContext(), 1, -1);
CGContextTranslateCTM(platformContext(), -rect.x(), -rect.y() - rect.height());
}
void GraphicsContext::beginTransparencyLayer(float opacity)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
CGContextSaveGState(context);
CGContextSetAlpha(context, opacity);
CGContextBeginTransparencyLayer(context, 0);
m_data->beginTransparencyLayer();
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
void GraphicsContext::endTransparencyLayer()
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
CGContextEndTransparencyLayer(context);
CGContextRestoreGState(context);
m_data->endTransparencyLayer();
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
void GraphicsContext::setPlatformShadow(const IntSize& offset, int blur, const Color& color, ColorSpace colorSpace)
{
if (paintingDisabled())
return;
CGFloat xOffset = offset.width();
CGFloat yOffset = offset.height();
CGFloat blurRadius = blur;
CGContextRef context = platformContext();
if (!m_common->state.shadowsIgnoreTransforms) {
CGAffineTransform userToBaseCTM = wkGetUserToBaseCTM(context);
CGFloat A = userToBaseCTM.a * userToBaseCTM.a + userToBaseCTM.b * userToBaseCTM.b;
CGFloat B = userToBaseCTM.a * userToBaseCTM.c + userToBaseCTM.b * userToBaseCTM.d;
CGFloat C = B;
CGFloat D = userToBaseCTM.c * userToBaseCTM.c + userToBaseCTM.d * userToBaseCTM.d;
CGFloat smallEigenvalue = narrowPrecisionToCGFloat(sqrt(0.5 * ((A + D) - sqrt(4 * B * C + (A - D) * (A - D)))));
// Extreme "blur" values can make text drawing crash or take crazy long times, so clamp
blurRadius = min(blur * smallEigenvalue, narrowPrecisionToCGFloat(1000.0));
CGSize offsetInBaseSpace = CGSizeApplyAffineTransform(offset, userToBaseCTM);
xOffset = offsetInBaseSpace.width;
yOffset = offsetInBaseSpace.height;
}
// Work around <rdar://problem/5539388> by ensuring that the offsets will get truncated
// to the desired integer.
static const CGFloat extraShadowOffset = narrowPrecisionToCGFloat(1.0 / 128);
if (xOffset > 0)
xOffset += extraShadowOffset;
else if (xOffset < 0)
xOffset -= extraShadowOffset;
if (yOffset > 0)
yOffset += extraShadowOffset;
else if (yOffset < 0)
yOffset -= extraShadowOffset;
// Check for an invalid color, as this means that the color was not set for the shadow
// and we should therefore just use the default shadow color.
if (!color.isValid())
CGContextSetShadow(context, CGSizeMake(xOffset, yOffset), blurRadius);
else {
RetainPtr<CGColorRef> colorCG(AdoptCF, createCGColorWithColorSpace(color, colorSpace));
CGContextSetShadowWithColor(context,
CGSizeMake(xOffset, yOffset),
blurRadius,
colorCG.get());
}
}
void GraphicsContext::clearPlatformShadow()
{
if (paintingDisabled())
return;
CGContextSetShadowWithColor(platformContext(), CGSizeZero, 0, 0);
}
void GraphicsContext::setMiterLimit(float limit)
{
if (paintingDisabled())
return;
CGContextSetMiterLimit(platformContext(), limit);
}
void GraphicsContext::setAlpha(float alpha)
{
if (paintingDisabled())
return;
CGContextSetAlpha(platformContext(), alpha);
}
void GraphicsContext::clearRect(const FloatRect& r)
{
if (paintingDisabled())
return;
CGContextClearRect(platformContext(), r);
}
void GraphicsContext::strokeRect(const FloatRect& r, float lineWidth)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
// FIXME: Is this helpful and correct in the strokePattern and strokeGradient cases?
setCGStrokeColorSpace(context, m_common->state.strokeColorSpace);
if (m_common->state.strokeGradient) {
CGContextSaveGState(context);
setStrokeThickness(lineWidth);
CGContextAddRect(context, r);
CGContextReplacePathWithStrokedPath(context);
CGContextClip(context);
m_common->state.strokeGradient->paint(this);
CGContextRestoreGState(context);
return;
}
if (m_common->state.strokePattern)
applyStrokePattern();
CGContextStrokeRectWithWidth(context, r, lineWidth);
}
void GraphicsContext::setLineCap(LineCap cap)
{
if (paintingDisabled())
return;
switch (cap) {
case ButtCap:
CGContextSetLineCap(platformContext(), kCGLineCapButt);
break;
case RoundCap:
CGContextSetLineCap(platformContext(), kCGLineCapRound);
break;
case SquareCap:
CGContextSetLineCap(platformContext(), kCGLineCapSquare);
break;
}
}
void GraphicsContext::setLineDash(const DashArray& dashes, float dashOffset)
{
CGContextSetLineDash(platformContext(), dashOffset, dashes.data(), dashes.size());
}
void GraphicsContext::setLineJoin(LineJoin join)
{
if (paintingDisabled())
return;
switch (join) {
case MiterJoin:
CGContextSetLineJoin(platformContext(), kCGLineJoinMiter);
break;
case RoundJoin:
CGContextSetLineJoin(platformContext(), kCGLineJoinRound);
break;
case BevelJoin:
CGContextSetLineJoin(platformContext(), kCGLineJoinBevel);
break;
}
}
void GraphicsContext::beginPath()
{
CGContextBeginPath(platformContext());
}
void GraphicsContext::addPath(const Path& path)
{
CGContextAddPath(platformContext(), path.platformPath());
}
void GraphicsContext::clip(const Path& path)
{
if (paintingDisabled())
return;
CGContextRef context = platformContext();
CGContextBeginPath(context);
CGContextAddPath(context, path.platformPath());
CGContextClip(context);
m_data->clip(path);
}
void GraphicsContext::canvasClip(const Path& path)
{
clip(path);
}
void GraphicsContext::clipOut(const Path& path)
{
if (paintingDisabled())
return;
CGContextBeginPath(platformContext());
CGContextAddRect(platformContext(), CGContextGetClipBoundingBox(platformContext()));
CGContextAddPath(platformContext(), path.platformPath());
CGContextEOClip(platformContext());
}
void GraphicsContext::scale(const FloatSize& size)
{
if (paintingDisabled())
return;
CGContextScaleCTM(platformContext(), size.width(), size.height());
m_data->scale(size);
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
void GraphicsContext::rotate(float angle)
{
if (paintingDisabled())
return;
CGContextRotateCTM(platformContext(), angle);
m_data->rotate(angle);
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
void GraphicsContext::translate(float x, float y)
{
if (paintingDisabled())
return;
CGContextTranslateCTM(platformContext(), x, y);
m_data->translate(x, y);
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
void GraphicsContext::concatCTM(const AffineTransform& transform)
{
if (paintingDisabled())
return;
CGContextConcatCTM(platformContext(), transform);
m_data->concatCTM(transform);
m_data->m_userToDeviceTransformKnownToBeIdentity = false;
}
AffineTransform GraphicsContext::getCTM() const
{
CGAffineTransform t = CGContextGetCTM(platformContext());
return AffineTransform(t.a, t.b, t.c, t.d, t.tx, t.ty);
}
FloatRect GraphicsContext::roundToDevicePixels(const FloatRect& rect)
{
// It is not enough just to round to pixels in device space. The rotation part of the
// affine transform matrix to device space can mess with this conversion if we have a
// rotating image like the hands of the world clock widget. We just need the scale, so
// we get the affine transform matrix and extract the scale.
if (m_data->m_userToDeviceTransformKnownToBeIdentity)
return rect;
CGAffineTransform deviceMatrix = CGContextGetUserSpaceToDeviceSpaceTransform(platformContext());
if (CGAffineTransformIsIdentity(deviceMatrix)) {
m_data->m_userToDeviceTransformKnownToBeIdentity = true;
return rect;
}
float deviceScaleX = sqrtf(deviceMatrix.a * deviceMatrix.a + deviceMatrix.b * deviceMatrix.b);
float deviceScaleY = sqrtf(deviceMatrix.c * deviceMatrix.c + deviceMatrix.d * deviceMatrix.d);
CGPoint deviceOrigin = CGPointMake(rect.x() * deviceScaleX, rect.y() * deviceScaleY);
CGPoint deviceLowerRight = CGPointMake((rect.x() + rect.width()) * deviceScaleX,
(rect.y() + rect.height()) * deviceScaleY);
deviceOrigin.x = roundf(deviceOrigin.x);
deviceOrigin.y = roundf(deviceOrigin.y);
deviceLowerRight.x = roundf(deviceLowerRight.x);
deviceLowerRight.y = roundf(deviceLowerRight.y);
// Don't let the height or width round to 0 unless either was originally 0
if (deviceOrigin.y == deviceLowerRight.y && rect.height())
deviceLowerRight.y += 1;
if (deviceOrigin.x == deviceLowerRight.x && rect.width())
deviceLowerRight.x += 1;
FloatPoint roundedOrigin = FloatPoint(deviceOrigin.x / deviceScaleX, deviceOrigin.y / deviceScaleY);
FloatPoint roundedLowerRight = FloatPoint(deviceLowerRight.x / deviceScaleX, deviceLowerRight.y / deviceScaleY);
return FloatRect(roundedOrigin, roundedLowerRight - roundedOrigin);
}
void GraphicsContext::drawLineForText(const IntPoint& point, int width, bool printing)
{
if (paintingDisabled())
return;
if (width <= 0)
return;
float x = point.x();
float y = point.y();
float lineLength = width;
// Use a minimum thickness of 0.5 in user space.
// See http://bugs.webkit.org/show_bug.cgi?id=4255 for details of why 0.5 is the right minimum thickness to use.
float thickness = max(strokeThickness(), 0.5f);
bool restoreAntialiasMode = false;
if (!printing) {
// On screen, use a minimum thickness of 1.0 in user space (later rounded to an integral number in device space).
float adjustedThickness = max(thickness, 1.0f);
// FIXME: This should be done a better way.
// We try to round all parameters to integer boundaries in device space. If rounding pixels in device space
// makes our thickness more than double, then there must be a shrinking-scale factor and rounding to pixels
// in device space will make the underlines too thick.
CGRect lineRect = roundToDevicePixels(FloatRect(x, y, lineLength, adjustedThickness));
if (lineRect.size.height < thickness * 2.0) {
x = lineRect.origin.x;
y = lineRect.origin.y;
lineLength = lineRect.size.width;
thickness = lineRect.size.height;
if (shouldAntialias()) {
CGContextSetShouldAntialias(platformContext(), false);
restoreAntialiasMode = true;
}
}
}
if (fillColor() != strokeColor())
setCGFillColor(platformContext(), strokeColor(), strokeColorSpace());
CGContextFillRect(platformContext(), CGRectMake(x, y, lineLength, thickness));
if (fillColor() != strokeColor())
setCGFillColor(platformContext(), fillColor(), fillColorSpace());
if (restoreAntialiasMode)
CGContextSetShouldAntialias(platformContext(), true);
}
void GraphicsContext::setURLForRect(const KURL& link, const IntRect& destRect)
{
if (paintingDisabled())
return;
RetainPtr<CFURLRef> urlRef(AdoptCF, link.createCFURL());
if (!urlRef)
return;
CGContextRef context = platformContext();
// Get the bounding box to handle clipping.
CGRect box = CGContextGetClipBoundingBox(context);
IntRect intBox((int)box.origin.x, (int)box.origin.y, (int)box.size.width, (int)box.size.height);
IntRect rect = destRect;
rect.intersect(intBox);
CGPDFContextSetURLForRect(context, urlRef.get(),
CGRectApplyAffineTransform(rect, CGContextGetCTM(context)));
}
void GraphicsContext::setImageInterpolationQuality(InterpolationQuality mode)
{
if (paintingDisabled())
return;
CGInterpolationQuality quality = kCGInterpolationDefault;
switch (mode) {
case InterpolationDefault:
quality = kCGInterpolationDefault;
break;
case InterpolationNone:
quality = kCGInterpolationNone;
break;
case InterpolationLow:
quality = kCGInterpolationLow;
break;
// Fall through to InterpolationHigh if kCGInterpolationMedium is not usable.
case InterpolationMedium:
#if USE(CG_INTERPOLATION_MEDIUM)
quality = kCGInterpolationMedium;
break;
#endif
case InterpolationHigh:
quality = kCGInterpolationHigh;
break;
}
CGContextSetInterpolationQuality(platformContext(), quality);
}
InterpolationQuality GraphicsContext::imageInterpolationQuality() const
{
if (paintingDisabled())
return InterpolationDefault;
CGInterpolationQuality quality = CGContextGetInterpolationQuality(platformContext());
switch (quality) {
case kCGInterpolationDefault:
return InterpolationDefault;
case kCGInterpolationNone:
return InterpolationNone;
case kCGInterpolationLow:
return InterpolationLow;
#if HAVE(CG_INTERPOLATION_MEDIUM)
// kCGInterpolationMedium is known to be present in the CGInterpolationQuality enum.
case kCGInterpolationMedium:
#if USE(CG_INTERPOLATION_MEDIUM)
// Only map to InterpolationMedium if targeting a system that understands it.
return InterpolationMedium;
#else
return InterpolationDefault;
#endif // USE(CG_INTERPOLATION_MEDIUM)
#endif // HAVE(CG_INTERPOLATION_MEDIUM)
case kCGInterpolationHigh:
return InterpolationHigh;
}
return InterpolationDefault;
}
void GraphicsContext::setPlatformTextDrawingMode(int mode)
{
if (paintingDisabled())
return;
// Wow, wish CG had used bits here.
CGContextRef context = platformContext();
switch (mode) {
case cTextInvisible: // Invisible
CGContextSetTextDrawingMode(context, kCGTextInvisible);
break;
case cTextFill: // Fill
CGContextSetTextDrawingMode(context, kCGTextFill);
break;
case cTextStroke: // Stroke
CGContextSetTextDrawingMode(context, kCGTextStroke);
break;
case 3: // Fill | Stroke
CGContextSetTextDrawingMode(context, kCGTextFillStroke);
break;
case cTextClip: // Clip
CGContextSetTextDrawingMode(context, kCGTextClip);
break;
case 5: // Fill | Clip
CGContextSetTextDrawingMode(context, kCGTextFillClip);
break;
case 6: // Stroke | Clip
CGContextSetTextDrawingMode(context, kCGTextStrokeClip);
break;
case 7: // Fill | Stroke | Clip
CGContextSetTextDrawingMode(context, kCGTextFillStrokeClip);
break;
default:
break;
}
}
void GraphicsContext::setPlatformStrokeColor(const Color& color, ColorSpace colorSpace)
{
if (paintingDisabled())
return;
setCGStrokeColor(platformContext(), color, colorSpace);
}
void GraphicsContext::setPlatformStrokeThickness(float thickness)
{
if (paintingDisabled())
return;
CGContextSetLineWidth(platformContext(), thickness);
}
void GraphicsContext::setPlatformFillColor(const Color& color, ColorSpace colorSpace)
{
if (paintingDisabled())
return;
setCGFillColor(platformContext(), color, colorSpace);
}
void GraphicsContext::setPlatformShouldAntialias(bool enable)
{
if (paintingDisabled())
return;
CGContextSetShouldAntialias(platformContext(), enable);
}
#ifndef BUILDING_ON_TIGER // Tiger's setCompositeOperation() is defined in GraphicsContextMac.mm.
void GraphicsContext::setCompositeOperation(CompositeOperator mode)
{
if (paintingDisabled())
return;
CGBlendMode target = kCGBlendModeNormal;
switch (mode) {
case CompositeClear:
target = kCGBlendModeClear;
break;
case CompositeCopy:
target = kCGBlendModeCopy;
break;
case CompositeSourceOver:
//kCGBlendModeNormal
break;
case CompositeSourceIn:
target = kCGBlendModeSourceIn;
break;
case CompositeSourceOut:
target = kCGBlendModeSourceOut;
break;
case CompositeSourceAtop:
target = kCGBlendModeSourceAtop;
break;
case CompositeDestinationOver:
target = kCGBlendModeDestinationOver;
break;
case CompositeDestinationIn:
target = kCGBlendModeDestinationIn;
break;
case CompositeDestinationOut:
target = kCGBlendModeDestinationOut;
break;
case CompositeDestinationAtop:
target = kCGBlendModeDestinationAtop;
break;
case CompositeXOR:
target = kCGBlendModeXOR;
break;
case CompositePlusDarker:
target = kCGBlendModePlusDarker;
break;
case CompositeHighlight:
// currently unsupported
break;
case CompositePlusLighter:
target = kCGBlendModePlusLighter;
break;
}
CGContextSetBlendMode(platformContext(), target);
}
#endif
}