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Diffstat (limited to 'WebCore/html/HTMLCanvasElement.cpp')
| -rw-r--r-- | WebCore/html/HTMLCanvasElement.cpp | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/WebCore/html/HTMLCanvasElement.cpp b/WebCore/html/HTMLCanvasElement.cpp new file mode 100644 index 0000000..f3ca1fd --- /dev/null +++ b/WebCore/html/HTMLCanvasElement.cpp @@ -0,0 +1,271 @@ +/* + * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved. + * Copyright (C) 2007 Alp Toker <alp@atoker.com> + * + * 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. + */ + +#include "config.h" +#include "HTMLCanvasElement.h" + +#include "CanvasGradient.h" +#include "CanvasPattern.h" +#include "CanvasRenderingContext2D.h" +#include "CanvasStyle.h" +#include "Chrome.h" +#include "Document.h" +#include "ExceptionCode.h" +#include "Frame.h" +#include "GraphicsContext.h" +#include "HTMLNames.h" +#include "ImageBuffer.h" +#include "MIMETypeRegistry.h" +#include "Page.h" +#include "RenderHTMLCanvas.h" +#include "Settings.h" +#include <kjs/interpreter.h> +#include <math.h> +#include <stdio.h> + +namespace WebCore { + +using namespace HTMLNames; + +// These values come from the WhatWG spec. +static const int defaultWidth = 300; +static const int defaultHeight = 150; + +// Firefox limits width/height to 32767 pixels, but slows down dramatically before it +// reaches that limit. We limit by area instead, giving us larger maximum dimensions, +// in exchange for a smaller maximum canvas size. +const float HTMLCanvasElement::MaxCanvasArea = 32768 * 8192; // Maximum canvas area in CSS pixels + +HTMLCanvasElement::HTMLCanvasElement(Document* doc) + : HTMLElement(canvasTag, doc) + , m_size(defaultWidth, defaultHeight) + , m_observer(0) + , m_originClean(true) + , m_ignoreReset(false) + , m_createdImageBuffer(false) +{ +} + +HTMLCanvasElement::~HTMLCanvasElement() +{ +} + +#if ENABLE(DASHBOARD_SUPPORT) + +HTMLTagStatus HTMLCanvasElement::endTagRequirement() const +{ + Settings* settings = document()->settings(); + if (settings && settings->usesDashboardBackwardCompatibilityMode()) + return TagStatusForbidden; + + return HTMLElement::endTagRequirement(); +} + +int HTMLCanvasElement::tagPriority() const +{ + Settings* settings = document()->settings(); + if (settings && settings->usesDashboardBackwardCompatibilityMode()) + return 0; + + return HTMLElement::tagPriority(); +} + +#endif + +void HTMLCanvasElement::parseMappedAttribute(MappedAttribute* attr) +{ + const QualifiedName& attrName = attr->name(); + if (attrName == widthAttr || attrName == heightAttr) + reset(); + HTMLElement::parseMappedAttribute(attr); +} + +RenderObject* HTMLCanvasElement::createRenderer(RenderArena* arena, RenderStyle* style) +{ + Settings* settings = document()->settings(); + if (settings && settings->isJavaScriptEnabled()) { + m_rendererIsCanvas = true; + return new (arena) RenderHTMLCanvas(this); + } + + m_rendererIsCanvas = false; + return HTMLElement::createRenderer(arena, style); +} + +void HTMLCanvasElement::setHeight(int value) +{ + setAttribute(heightAttr, String::number(value)); +} + +void HTMLCanvasElement::setWidth(int value) +{ + setAttribute(widthAttr, String::number(value)); +} + +String HTMLCanvasElement::toDataURL(const String& mimeType, ExceptionCode& ec) +{ + if (!m_originClean) { + ec = SECURITY_ERR; + return String(); + } + + if (m_size.isEmpty()) + return String("data:,"); + + if (mimeType.isNull() || !MIMETypeRegistry::isSupportedImageMIMETypeForEncoding(mimeType)) + return buffer()->toDataURL("image/png"); + + return buffer()->toDataURL(mimeType); +} + +CanvasRenderingContext* HTMLCanvasElement::getContext(const String& type) +{ + if (type == "2d") { + if (!m_2DContext) + m_2DContext.set(new CanvasRenderingContext2D(this)); + return m_2DContext.get(); + } + return 0; +} + +void HTMLCanvasElement::willDraw(const FloatRect& rect) +{ + m_imageBuffer->clearImage(); + + if (RenderObject* ro = renderer()) { +#ifdef CANVAS_INCREMENTAL_REPAINT + // Handle CSS triggered scaling + float widthScale = static_cast<float>(ro->width()) / static_cast<float>(m_size.width()); + float heightScale = static_cast<float>(ro->height()) / static_cast<float>(m_size.height()); + FloatRect r(rect.x() * widthScale, rect.y() * heightScale, rect.width() * widthScale, rect.height() * heightScale); + ro->repaintRectangle(enclosingIntRect(r)); +#else + ro->repaint(); +#endif + } + + if (m_observer) + m_observer->canvasChanged(this, rect); +} + +void HTMLCanvasElement::reset() +{ + if (m_ignoreReset) + return; + + bool ok; + int w = getAttribute(widthAttr).toInt(&ok); + if (!ok) + w = defaultWidth; + int h = getAttribute(heightAttr).toInt(&ok); + if (!ok) + h = defaultHeight; + + IntSize oldSize = m_size; + m_size = IntSize(w, h); + + bool hadImageBuffer = m_createdImageBuffer; + m_createdImageBuffer = false; + m_imageBuffer.clear(); + if (m_2DContext) + m_2DContext->reset(); + + if (RenderObject* ro = renderer()) + if (m_rendererIsCanvas) { + if (oldSize != m_size) + static_cast<RenderHTMLCanvas*>(ro)->canvasSizeChanged(); + if (hadImageBuffer) + ro->repaint(); + } + + if (m_observer) + m_observer->canvasResized(this); +} + +void HTMLCanvasElement::paint(GraphicsContext* context, const IntRect& r) +{ + if (context->paintingDisabled()) + return; + + if (m_imageBuffer) { + Image* image = m_imageBuffer->image(); + if (image) + context->drawImage(image, r); + } +} + +IntRect HTMLCanvasElement::convertLogicalToDevice(const FloatRect& logicalRect) const +{ + return IntRect(convertLogicalToDevice(logicalRect.location()), convertLogicalToDevice(logicalRect.size())); +} + +IntSize HTMLCanvasElement::convertLogicalToDevice(const FloatSize& logicalSize) const +{ + float pageScaleFactor = document()->frame() ? document()->frame()->page()->chrome()->scaleFactor() : 1.0f; + float wf = ceilf(logicalSize.width() * pageScaleFactor); + float hf = ceilf(logicalSize.height() * pageScaleFactor); + + if (!(wf >= 1 && hf >= 1 && wf * hf <= MaxCanvasArea)) + return IntSize(); + + return IntSize(static_cast<unsigned>(wf), static_cast<unsigned>(hf)); +} + +IntPoint HTMLCanvasElement::convertLogicalToDevice(const FloatPoint& logicalPos) const +{ + float pageScaleFactor = document()->frame() ? document()->frame()->page()->chrome()->scaleFactor() : 1.0f; + float xf = logicalPos.x() * pageScaleFactor; + float yf = logicalPos.y() * pageScaleFactor; + + return IntPoint(static_cast<unsigned>(xf), static_cast<unsigned>(yf)); +} + +void HTMLCanvasElement::createImageBuffer() const +{ + ASSERT(!m_imageBuffer); + + m_createdImageBuffer = true; + + FloatSize unscaledSize(width(), height()); + IntSize size = convertLogicalToDevice(unscaledSize); + if (!size.width() || !size.height()) + return; + m_imageBuffer.set(ImageBuffer::create(size, false).release()); +} + +GraphicsContext* HTMLCanvasElement::drawingContext() const +{ + return buffer() ? m_imageBuffer->context() : 0; +} + +ImageBuffer* HTMLCanvasElement::buffer() const +{ + if (!m_createdImageBuffer) + createImageBuffer(); + return m_imageBuffer.get(); +} + +} |