canvasrenderingcontext2d.cpp

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void CanvasRenderingContext2D::setFillColor(const String& color)
{
    setFillStyle(CanvasStyle::create(color));
}

void CanvasRenderingContext2D::setFillColor(float grayLevel)
{
    setFillStyle(CanvasStyle::create(grayLevel, 1));
}

void CanvasRenderingContext2D::setFillColor(const String& color, float alpha)
{
    setFillStyle(CanvasStyle::create(color, alpha));
}

void CanvasRenderingContext2D::setFillColor(float grayLevel, float alpha)
{
    setFillStyle(CanvasStyle::create(grayLevel, alpha));
}

void CanvasRenderingContext2D::setFillColor(float r, float g, float b, float a)
{
    setFillStyle(CanvasStyle::create(r, g, b, a));
}

void CanvasRenderingContext2D::setFillColor(float c, float m, float y, float k, float a)
{
    setFillStyle(CanvasStyle::create(c, m, y, k, a));
}

void CanvasRenderingContext2D::beginPath()
{
    m_path.clear();
}

void CanvasRenderingContext2D::closePath()
{
    m_path.closeSubpath();
}

void CanvasRenderingContext2D::moveTo(float x, float y)
{
    if (!isfinite(x) | !isfinite(y))
        return;
    if (!state().m_invertibleCTM)
        return;
    m_path.moveTo(FloatPoint(x, y));
}

void CanvasRenderingContext2D::lineTo(float x, float y)
{
    if (!isfinite(x) | !isfinite(y))
        return;
    if (!state().m_invertibleCTM)
        return;
    m_path.addLineTo(FloatPoint(x, y));
}

void CanvasRenderingContext2D::quadraticCurveTo(float cpx, float cpy, float x, float y)
{
    if (!isfinite(cpx) | !isfinite(cpy) | !isfinite(x) | !isfinite(y))
        return;
    if (!state().m_invertibleCTM)
        return;
    m_path.addQuadCurveTo(FloatPoint(cpx, cpy), FloatPoint(x, y));
}

void CanvasRenderingContext2D::bezierCurveTo(float cp1x, float cp1y, float cp2x, float cp2y, float x, float y)
{
    if (!isfinite(cp1x) | !isfinite(cp1y) | !isfinite(cp2x) | !isfinite(cp2y) | !isfinite(x) | !isfinite(y))
        return;
    if (!state().m_invertibleCTM)
        return;
    m_path.addBezierCurveTo(FloatPoint(cp1x, cp1y), FloatPoint(cp2x, cp2y), FloatPoint(x, y));
}

void CanvasRenderingContext2D::arcTo(float x0, float y0, float x1, float y1, float r, ExceptionCode& ec)
{
    ec = 0;
    if (!isfinite(x0) | !isfinite(y0) | !isfinite(x1) | !isfinite(y1) | !isfinite(r))
        return;
    
    if (r < 0) {
        ec = INDEX_SIZE_ERR;
        return;
    }
    if (!state().m_invertibleCTM)
        return;
    m_path.addArcTo(FloatPoint(x0, y0), FloatPoint(x1, y1), r);
}

void CanvasRenderingContext2D::arc(float x, float y, float r, float sa, float ea, bool anticlockwise, ExceptionCode& ec)
{
    ec = 0;
    if (!isfinite(x) | !isfinite(y) | !isfinite(r) | !isfinite(sa) | !isfinite(ea))
        return;
    
    if (r < 0) {
        ec = INDEX_SIZE_ERR;
        return;
    }
    if (!state().m_invertibleCTM)
        return;
    m_path.addArc(FloatPoint(x, y), r, sa, ea, anticlockwise);
}
    
static bool validateRectForCanvas(float& x, float& y, float& width, float& height)
{
    if (!isfinite(x) | !isfinite(y) | !isfinite(width) | !isfinite(height))
        return false;
    
    if (width < 0) {
        width = -width;
        x -= width;
    }
    
    if (height < 0) {
        height = -height;
        y -= height;
    }
    
    return true;
}

void CanvasRenderingContext2D::rect(float x, float y, float width, float height)
{
    if (!validateRectForCanvas(x, y, width, height))
        return;
    if (!state().m_invertibleCTM)
        return;
    m_path.addRect(FloatRect(x, y, width, height));
}

#if ENABLE(DASHBOARD_SUPPORT)
void CanvasRenderingContext2D::clearPathForDashboardBackwardCompatibilityMode()
{
    if (Settings* settings = m_canvas->document()->settings())
        if (settings->usesDashboardBackwardCompatibilityMode())
            m_path.clear();
}
#endif

void CanvasRenderingContext2D::fill()
{
    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;

    if (!m_path.isEmpty()) {
        c->beginPath();
        c->addPath(m_path);
        willDraw(m_path.boundingRect());
        c->fillPath();
    }

#if ENABLE(DASHBOARD_SUPPORT)
    clearPathForDashboardBackwardCompatibilityMode();
#endif
}

void CanvasRenderingContext2D::stroke()
{
    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;

    if (!m_path.isEmpty()) {
        c->beginPath();
        c->addPath(m_path);

        CanvasStrokeStyleApplier strokeApplier(this);
        FloatRect boundingRect = m_path.strokeBoundingRect(&strokeApplier);
        willDraw(boundingRect);

        c->strokePath();
    }

#if ENABLE(DASHBOARD_SUPPORT)
    clearPathForDashboardBackwardCompatibilityMode();
#endif
}

void CanvasRenderingContext2D::clip()
{
    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;
    c->clip(m_path);
#if ENABLE(DASHBOARD_SUPPORT)
    clearPathForDashboardBackwardCompatibilityMode();
#endif
}

bool CanvasRenderingContext2D::isPointInPath(const float x, const float y)
{
    GraphicsContext* c = drawingContext();
    if (!c)
        return false;
    if (!state().m_invertibleCTM)
        return false;

    FloatPoint point(x, y);
    TransformationMatrix ctm = state().m_transform;
    FloatPoint transformedPoint = ctm.inverse().mapPoint(point);
    return m_path.contains(transformedPoint);
}

void CanvasRenderingContext2D::clearRect(float x, float y, float width, float height)
{
    if (!validateRectForCanvas(x, y, width, height))
        return;
    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;
    FloatRect rect(x, y, width, height);
    willDraw(rect);
    c->clearRect(rect);
}

void CanvasRenderingContext2D::fillRect(float x, float y, float width, float height)
{
    if (!validateRectForCanvas(x, y, width, height))
        return;

    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;

    FloatRect rect(x, y, width, height);
    willDraw(rect);

    c->save();
    c->fillRect(rect);
    c->restore();
}

void CanvasRenderingContext2D::strokeRect(float x, float y, float width, float height)
{
    if (!validateRectForCanvas(x, y, width, height))
        return;
    strokeRect(x, y, width, height, state().m_lineWidth);
}

void CanvasRenderingContext2D::strokeRect(float x, float y, float width, float height, float lineWidth)
{
    if (!validateRectForCanvas(x, y, width, height))
        return;
    
    if (!(lineWidth >= 0))
        return;

    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;

    FloatRect rect(x, y, width, height);

    FloatRect boundingRect = rect;
    boundingRect.inflate(lineWidth / 2);
    willDraw(boundingRect);

    c->strokeRect(rect, lineWidth);
}

#if PLATFORM(CG)
static inline CGSize adjustedShadowSize(CGFloat width, CGFloat height)
{
    // Work around <rdar://problem/5539388> by ensuring that shadow offsets will get truncated
    // to the desired integer.
    static const CGFloat extraShadowOffset = narrowPrecisionToCGFloat(1.0 / 128);
    if (width > 0)
        width += extraShadowOffset;
    else if (width < 0)
        width -= extraShadowOffset;

    if (height > 0)
        height += extraShadowOffset;
    else if (height < 0)
        height -= extraShadowOffset;

    return CGSizeMake(width, height);
}
#endif

void CanvasRenderingContext2D::setShadow(float width, float height, float blur)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = "";
    applyShadow();
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, const String& color)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = color;
    applyShadow();
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float grayLevel)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = "";

    GraphicsContext* c = drawingContext();
    if (!c)
        return;

    RGBA32 rgba = makeRGBA32FromFloats(grayLevel, grayLevel, grayLevel, 1.0f);
    c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba));
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, const String& color, float alpha)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = color;

    GraphicsContext* c = drawingContext();
    if (!c)
        return;

    RGBA32 rgba = 0; // default is transparent black
    if (!state().m_shadowColor.isEmpty())
        CSSParser::parseColor(rgba, state().m_shadowColor);
    c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(colorWithOverrideAlpha(rgba, alpha)));
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float grayLevel, float alpha)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = "";

    GraphicsContext* c = drawingContext();
    if (!c)
        return;

    RGBA32 rgba = makeRGBA32FromFloats(grayLevel, grayLevel, grayLevel, alpha);
    c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba));
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float r, float g, float b, float a)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = "";

    GraphicsContext* c = drawingContext();
    if (!c)
        return;

    RGBA32 rgba = makeRGBA32FromFloats(r, g, b, a); // default is transparent black
    if (!state().m_shadowColor.isEmpty())
        CSSParser::parseColor(rgba, state().m_shadowColor);
    c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba));
}

void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float c, float m, float y, float k, float a)
{
    state().m_shadowOffset = FloatSize(width, height);
    state().m_shadowBlur = blur;
    state().m_shadowColor = "";

    GraphicsContext* dc = drawingContext();
    if (!dc)
        return;
#if PLATFORM(CG)
    const CGFloat components[5] = { c, m, y, k, a };
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceCMYK();
    CGColorRef shadowColor = CGColorCreate(colorSpace, components);
    CGColorSpaceRelease(colorSpace);
    CGContextSetShadowWithColor(dc->platformContext(), adjustedShadowSize(width, -height), blur, shadowColor);
    CGColorRelease(shadowColor);
#else
    dc->setShadow(IntSize(width, -height), blur, Color(c, m, y, k, a));
#endif
}

void CanvasRenderingContext2D::clearShadow()
{
    state().m_shadowOffset = FloatSize();
    state().m_shadowBlur = 0;
    state().m_shadowColor = "";
    applyShadow();
}

void CanvasRenderingContext2D::applyShadow()
{
    GraphicsContext* c = drawingContext();
    if (!c)
        return;

    RGBA32 rgba = 0; // default is transparent black
    if (!state().m_shadowColor.isEmpty())
        CSSParser::parseColor(rgba, state().m_shadowColor);
    float width = state().m_shadowOffset.width();
    float height = state().m_shadowOffset.height();
    c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba));
}

static IntSize size(HTMLImageElement* image)
{
    if (CachedImage* cachedImage = image->cachedImage())
        return cachedImage->imageSize(1.0f); // FIXME: Not sure about this.
    return IntSize();
}

static inline FloatRect normalizeRect(const FloatRect& rect)
{
    return FloatRect(min(rect.x(), rect.right()),
        min(rect.y(), rect.bottom()),
        max(rect.width(), -rect.width()),
        max(rect.height(), -rect.height()));
}

void CanvasRenderingContext2D::drawImage(HTMLImageElement* image, float x, float y)
{
    ASSERT(image);
    IntSize s = size(image);
    ExceptionCode ec;
    drawImage(image, x, y, s.width(), s.height(), ec);
}

void CanvasRenderingContext2D::drawImage(HTMLImageElement* image,
    float x, float y, float width, float height, ExceptionCode& ec)
{
    ASSERT(image);
    IntSize s = size(image);
    drawImage(image, FloatRect(0, 0, s.width(), s.height()), FloatRect(x, y, width, height), ec);
}

void CanvasRenderingContext2D::checkOrigin(const KURL& url)
{
    RefPtr<SecurityOrigin> origin = SecurityOrigin::create(url);
    if (!m_canvas->document()->securityOrigin()->canAccess(origin.get()))
        m_canvas->setOriginTainted();
}

void CanvasRenderingContext2D::drawImage(HTMLImageElement* image, const FloatRect& srcRect, const FloatRect& dstRect,
    ExceptionCode& ec)
{
    ASSERT(image);

    ec = 0;

    FloatRect imageRect = FloatRect(FloatPoint(), size(image));
    if (!imageRect.contains(normalizeRect(srcRect)) || srcRect.width() == 0 || srcRect.height() == 0) {
        ec = INDEX_SIZE_ERR;
        return;
    }

    if (!dstRect.width() || !dstRect.height())
        return;

    GraphicsContext* c = drawingContext();
    if (!c)
        return;
    if (!state().m_invertibleCTM)
        return;

    CachedImage* cachedImage = image->cachedImage();
    if (!cachedImage)
        return;

    if (m_canvas->originClean())
        checkOrigin(cachedImage->response().url());

    if (m_canvas->originClean() && !cachedImage->image()->hasSingleSecurityOrigin())
        m_canvas->setOriginTainted();

    FloatRect sourceRect = c->roundToDevicePixels(srcRect);
    FloatRect destRect = c->roundToDevicePixels(dstRect);
    willDraw(destRect);