1 /* 2 * Copyright (C) 2007, 2008 Rob Buis <buis (at) kde.org> 3 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann (at) kde.org> 4 * Copyright (C) 2007 Eric Seidel <eric (at) webkit.org> 5 * Copyright (C) 2009 Google, Inc. All rights reserved. 6 * Copyright (C) 2009 Dirk Schulze <krit (at) webkit.org> 7 * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved. 8 * 9 * This library is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU Library General Public 11 * License as published by the Free Software Foundation; either 12 * version 2 of the License, or (at your option) any later version. 13 * 14 * This library is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Library General Public License for more details. 18 * 19 * You should have received a copy of the GNU Library General Public License 20 * along with this library; see the file COPYING.LIB. If not, write to 21 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 22 * Boston, MA 02110-1301, USA. 23 */ 24 25 #include "config.h" 26 27 #include "core/rendering/svg/SVGRenderingContext.h" 28 29 #include "core/frame/FrameHost.h" 30 #include "core/frame/FrameView.h" 31 #include "core/frame/LocalFrame.h" 32 #include "core/frame/Settings.h" 33 #include "core/rendering/RenderLayer.h" 34 #include "core/rendering/svg/RenderSVGImage.h" 35 #include "core/rendering/svg/RenderSVGResource.h" 36 #include "core/rendering/svg/RenderSVGResourceFilter.h" 37 #include "core/rendering/svg/RenderSVGResourceMasker.h" 38 #include "core/rendering/svg/SVGResources.h" 39 #include "core/rendering/svg/SVGResourcesCache.h" 40 41 static int kMaxImageBufferSize = 4096; 42 43 namespace WebCore { 44 45 static inline bool isRenderingMaskImage(RenderObject* object) 46 { 47 if (object->frame() && object->frame()->view()) 48 return object->frame()->view()->paintBehavior() & PaintBehaviorRenderingSVGMask; 49 return false; 50 } 51 52 SVGRenderingContext::~SVGRenderingContext() 53 { 54 // Fast path if we don't need to restore anything. 55 if (!(m_renderingFlags & ActionsNeeded)) 56 return; 57 58 ASSERT(m_object && m_paintInfo); 59 60 if (m_renderingFlags & PostApplyResources) { 61 ASSERT(m_masker || m_clipper || m_filter); 62 ASSERT(SVGResourcesCache::cachedResourcesForRenderObject(m_object)); 63 64 if (m_filter) { 65 ASSERT(SVGResourcesCache::cachedResourcesForRenderObject(m_object)->filter() == m_filter); 66 m_filter->postApplyResource(m_object, m_paintInfo->context, ApplyToDefaultMode, 0, 0); 67 m_paintInfo->context = m_savedContext; 68 m_paintInfo->rect = m_savedPaintRect; 69 } 70 71 if (m_clipper) { 72 ASSERT(SVGResourcesCache::cachedResourcesForRenderObject(m_object)->clipper() == m_clipper); 73 m_clipper->postApplyStatefulResource(m_object, m_paintInfo->context, m_clipperContext); 74 } 75 76 if (m_masker) { 77 ASSERT(SVGResourcesCache::cachedResourcesForRenderObject(m_object)->masker() == m_masker); 78 m_masker->postApplyResource(m_object, m_paintInfo->context, ApplyToDefaultMode, 0, 0); 79 } 80 } 81 82 if (m_renderingFlags & EndOpacityLayer) 83 m_paintInfo->context->endLayer(); 84 85 if (m_renderingFlags & RestoreGraphicsContext) 86 m_paintInfo->context->restore(); 87 } 88 89 void SVGRenderingContext::prepareToRenderSVGContent(RenderObject* object, PaintInfo& paintInfo, NeedsGraphicsContextSave needsGraphicsContextSave) 90 { 91 ASSERT(object); 92 93 #ifndef NDEBUG 94 // This function must not be called twice! 95 ASSERT(!(m_renderingFlags & PrepareToRenderSVGContentWasCalled)); 96 m_renderingFlags |= PrepareToRenderSVGContentWasCalled; 97 #endif 98 99 m_object = object; 100 m_paintInfo = &paintInfo; 101 m_filter = 0; 102 103 // We need to save / restore the context even if the initialization failed. 104 if (needsGraphicsContextSave == SaveGraphicsContext) { 105 m_paintInfo->context->save(); 106 m_renderingFlags |= RestoreGraphicsContext; 107 } 108 109 RenderStyle* style = m_object->style(); 110 ASSERT(style); 111 112 const SVGRenderStyle* svgStyle = style->svgStyle(); 113 ASSERT(svgStyle); 114 115 // Setup transparency layers before setting up SVG resources! 116 bool isRenderingMask = isRenderingMaskImage(m_object); 117 // RenderLayer takes care of root opacity. 118 float opacity = (object->isSVGRoot() || isRenderingMask) ? 1 : style->opacity(); 119 bool hasBlendMode = style->hasBlendMode() && !isRenderingMask; 120 121 if (opacity < 1 || hasBlendMode || style->hasIsolation()) { 122 FloatRect repaintRect = m_object->paintInvalidationRectInLocalCoordinates(); 123 m_paintInfo->context->clip(repaintRect); 124 125 if (hasBlendMode) { 126 if (!(m_renderingFlags & RestoreGraphicsContext)) { 127 m_paintInfo->context->save(); 128 m_renderingFlags |= RestoreGraphicsContext; 129 } 130 m_paintInfo->context->setCompositeOperation(CompositeSourceOver, style->blendMode()); 131 } 132 133 m_paintInfo->context->beginTransparencyLayer(opacity); 134 135 if (hasBlendMode) 136 m_paintInfo->context->setCompositeOperation(CompositeSourceOver, blink::WebBlendModeNormal); 137 138 m_renderingFlags |= EndOpacityLayer; 139 } 140 141 ClipPathOperation* clipPathOperation = style->clipPath(); 142 if (clipPathOperation && clipPathOperation->type() == ClipPathOperation::SHAPE) { 143 ShapeClipPathOperation* clipPath = toShapeClipPathOperation(clipPathOperation); 144 m_paintInfo->context->clipPath(clipPath->path(object->objectBoundingBox()), clipPath->windRule()); 145 } 146 147 SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(m_object); 148 if (!resources) { 149 if (svgStyle->hasFilter()) 150 return; 151 152 m_renderingFlags |= RenderingPrepared; 153 return; 154 } 155 156 if (!isRenderingMask) { 157 if (RenderSVGResourceMasker* masker = resources->masker()) { 158 if (!masker->applyResource(m_object, style, m_paintInfo->context, ApplyToDefaultMode)) 159 return; 160 m_masker = masker; 161 m_renderingFlags |= PostApplyResources; 162 } 163 } 164 165 RenderSVGResourceClipper* clipper = resources->clipper(); 166 if (!clipPathOperation && clipper) { 167 if (!clipper->applyStatefulResource(m_object, m_paintInfo->context, m_clipperContext)) 168 return; 169 m_clipper = clipper; 170 m_renderingFlags |= PostApplyResources; 171 } 172 173 if (!isRenderingMask) { 174 m_filter = resources->filter(); 175 if (m_filter) { 176 m_savedContext = m_paintInfo->context; 177 m_savedPaintRect = m_paintInfo->rect; 178 // Return with false here may mean that we don't need to draw the content 179 // (because it was either drawn before or empty) but we still need to apply the filter. 180 m_renderingFlags |= PostApplyResources; 181 if (!m_filter->applyResource(m_object, style, m_paintInfo->context, ApplyToDefaultMode)) 182 return; 183 184 // Since we're caching the resulting bitmap and do not invalidate it on repaint rect 185 // changes, we need to paint the whole filter region. Otherwise, elements not visible 186 // at the time of the initial paint (due to scrolling, window size, etc.) will never 187 // be drawn. 188 m_paintInfo->rect = IntRect(m_filter->drawingRegion(m_object)); 189 } 190 } 191 192 m_renderingFlags |= RenderingPrepared; 193 } 194 195 static AffineTransform& currentContentTransformation() 196 { 197 DEFINE_STATIC_LOCAL(AffineTransform, s_currentContentTransformation, ()); 198 return s_currentContentTransformation; 199 } 200 201 float SVGRenderingContext::calculateScreenFontSizeScalingFactor(const RenderObject* renderer) 202 { 203 ASSERT(renderer); 204 205 AffineTransform ctm; 206 // FIXME: calculateDeviceSpaceTransformation() queries layer compositing state - which is not 207 // supported during layout. Hence, the result may not include all CSS transforms. 208 calculateDeviceSpaceTransformation(renderer, ctm); 209 return narrowPrecisionToFloat(sqrt((pow(ctm.xScale(), 2) + pow(ctm.yScale(), 2)) / 2)); 210 } 211 212 void SVGRenderingContext::calculateDeviceSpaceTransformation(const RenderObject* renderer, AffineTransform& absoluteTransform) 213 { 214 // FIXME: trying to compute a device space transform at record time is wrong. All clients 215 // should be updated to avoid relying on this information, and the method should be removed. 216 217 ASSERT(renderer); 218 // We're about to possibly clear renderer, so save the deviceScaleFactor now. 219 float deviceScaleFactor = renderer->document().frameHost()->deviceScaleFactor(); 220 221 // Walk up the render tree, accumulating SVG transforms. 222 absoluteTransform = currentContentTransformation(); 223 while (renderer) { 224 absoluteTransform = renderer->localToParentTransform() * absoluteTransform; 225 if (renderer->isSVGRoot()) 226 break; 227 renderer = renderer->parent(); 228 } 229 230 // Continue walking up the layer tree, accumulating CSS transforms. 231 RenderLayer* layer = renderer ? renderer->enclosingLayer() : 0; 232 while (layer && layer->isAllowedToQueryCompositingState()) { 233 // We can stop at compositing layers, to match the backing resolution. 234 // FIXME: should we be computing the transform to the nearest composited layer, 235 // or the nearest composited layer that does not paint into its ancestor? 236 // I think this is the nearest composited ancestor since we will inherit its 237 // transforms in the composited layer tree. 238 if (layer->compositingState() != NotComposited) 239 break; 240 241 if (TransformationMatrix* layerTransform = layer->transform()) 242 absoluteTransform = layerTransform->toAffineTransform() * absoluteTransform; 243 244 layer = layer->parent(); 245 } 246 247 absoluteTransform.scale(deviceScaleFactor); 248 } 249 250 void SVGRenderingContext::renderSubtree(GraphicsContext* context, RenderObject* item, const AffineTransform& subtreeContentTransformation) 251 { 252 ASSERT(item); 253 ASSERT(context); 254 255 PaintInfo info(context, PaintInfo::infiniteRect(), PaintPhaseForeground, PaintBehaviorNormal); 256 257 AffineTransform& contentTransformation = currentContentTransformation(); 258 AffineTransform savedContentTransformation = contentTransformation; 259 contentTransformation = subtreeContentTransformation * contentTransformation; 260 261 ASSERT(!item->needsLayout()); 262 item->paint(info, IntPoint()); 263 264 contentTransformation = savedContentTransformation; 265 } 266 267 FloatRect SVGRenderingContext::clampedAbsoluteTargetRect(const FloatRect& absoluteTargetRect) 268 { 269 const FloatSize maxImageBufferSize(kMaxImageBufferSize, kMaxImageBufferSize); 270 return FloatRect(absoluteTargetRect.location(), absoluteTargetRect.size().shrunkTo(maxImageBufferSize)); 271 } 272 273 void SVGRenderingContext::clear2DRotation(AffineTransform& transform) 274 { 275 AffineTransform::DecomposedType decomposition; 276 transform.decompose(decomposition); 277 decomposition.angle = 0; 278 transform.recompose(decomposition); 279 } 280 281 bool SVGRenderingContext::bufferForeground(OwnPtr<ImageBuffer>& imageBuffer) 282 { 283 ASSERT(m_paintInfo); 284 ASSERT(m_object->isSVGImage()); 285 FloatRect boundingBox = m_object->objectBoundingBox(); 286 287 // Invalidate an existing buffer if the scale is not correct. 288 if (imageBuffer) { 289 AffineTransform transform = m_paintInfo->context->getCTM(); 290 IntSize expandedBoundingBox = expandedIntSize(boundingBox.size()); 291 IntSize bufferSize(static_cast<int>(ceil(expandedBoundingBox.width() * transform.xScale())), static_cast<int>(ceil(expandedBoundingBox.height() * transform.yScale()))); 292 if (bufferSize != imageBuffer->size()) 293 imageBuffer.clear(); 294 } 295 296 // Create a new buffer and paint the foreground into it. 297 if (!imageBuffer) { 298 if ((imageBuffer = m_paintInfo->context->createCompatibleBuffer(expandedIntSize(boundingBox.size())))) { 299 GraphicsContext* bufferedRenderingContext = imageBuffer->context(); 300 bufferedRenderingContext->translate(-boundingBox.x(), -boundingBox.y()); 301 PaintInfo bufferedInfo(*m_paintInfo); 302 bufferedInfo.context = bufferedRenderingContext; 303 toRenderSVGImage(m_object)->paintForeground(bufferedInfo); 304 } else 305 return false; 306 } 307 308 m_paintInfo->context->drawImageBuffer(imageBuffer.get(), boundingBox); 309 return true; 310 } 311 312 } 313