src/third_party/WebKit/Source/core/rendering/RenderGeometryMap.cpp

   1 /*
   2  * Copyright (C) 2012 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "core/rendering/RenderGeometryMap.h"
  28
  29 #include "core/frame/LocalFrame.h"
  30 #include "core/rendering/RenderLayer.h"
  31 #include "core/rendering/RenderView.h"
  32 #include "platform/geometry/TransformState.h"
  33 #include "wtf/TemporaryChange.h"
  34
  35 namespace blink {
  36
  37 RenderGeometryMap::RenderGeometryMap(MapCoordinatesFlags flags)
  38     : m_insertionPosition(kNotFound)
  39     , m_nonUniformStepsCount(0)
  40     , m_transformedStepsCount(0)
  41     , m_fixedStepsCount(0)
  42     , m_mapCoordinatesFlags(flags)
  43 {
  44 }
  45
  46 RenderGeometryMap::~RenderGeometryMap()
  47 {
  48 }
  49
  50 void RenderGeometryMap::mapToContainer(TransformState& transformState, const RenderLayerModelObject* container) const
  51 {
  52     // If the mapping includes something like columns, we have to go via renderers.
  53     if (hasNonUniformStep()) {
  54         m_mapping.last().m_renderer->mapLocalToContainer(container, transformState, ApplyContainerFlip | m_mapCoordinatesFlags);
  55         transformState.flatten();
  56         return;
  57     }
  58
  59     bool inFixed = false;
  60 #if ENABLE(ASSERT)
  61     bool foundContainer = !container || (m_mapping.size() && m_mapping[0].m_renderer == container);
  62 #endif
  63
  64     for (int i = m_mapping.size() - 1; i >= 0; --i) {
  65         const RenderGeometryMapStep& currentStep = m_mapping[i];
  66
  67         // If container is the root RenderView (step 0) we want to apply its fixed position offset.
  68         if (i > 0 && currentStep.m_renderer == container) {
  69 #if ENABLE(ASSERT)
  70             foundContainer = true;
  71 #endif
  72             break;
  73         }
  74
  75         // If this box has a transform, it acts as a fixed position container
  76         // for fixed descendants, which prevents the propagation of 'fixed'
  77         // unless the layer itself is also fixed position.
  78         if (i && currentStep.m_hasTransform && !currentStep.m_isFixedPosition)
  79             inFixed = false;
  80         else if (currentStep.m_isFixedPosition)
  81             inFixed = true;
  82
  83         ASSERT(!i == isTopmostRenderView(currentStep.m_renderer));
  84
  85         if (!i) {
  86             // A null container indicates mapping through the root RenderView, so including its transform (the page scale).
  87             if (!container && currentStep.m_transform)
  88                 transformState.applyTransform(*currentStep.m_transform.get());
  89         } else {
  90             TransformState::TransformAccumulation accumulate = currentStep.m_accumulatingTransform ? TransformState::AccumulateTransform : TransformState::FlattenTransform;
  91             if (currentStep.m_transform)
  92                 transformState.applyTransform(*currentStep.m_transform.get(), accumulate);
  93             else
  94                 transformState.move(currentStep.m_offset.width(), currentStep.m_offset.height(), accumulate);
  95         }
  96
  97         if (inFixed && !currentStep.m_offsetForFixedPosition.isZero()) {
  98             ASSERT(currentStep.m_renderer->isRenderView());
  99             transformState.move(currentStep.m_offsetForFixedPosition);
 100         }
 101     }
 102
 103     ASSERT(foundContainer);
 104     transformState.flatten();
 105 }
 106
 107 FloatPoint RenderGeometryMap::mapToContainer(const FloatPoint& p, const RenderLayerModelObject* container) const
 108 {
 109     FloatPoint result;
 110
 111     if (!hasFixedPositionStep() && !hasTransformStep() && !hasNonUniformStep() && (!container || (m_mapping.size() && container == m_mapping[0].m_renderer)))
 112         result = p + m_accumulatedOffset;
 113     else {
 114         TransformState transformState(TransformState::ApplyTransformDirection, p);
 115         mapToContainer(transformState, container);
 116         result = transformState.lastPlanarPoint();
 117     }
 118
 119 #if ENABLE(ASSERT)
 120     if (m_mapping.size() > 0) {
 121         const RenderObject* lastRenderer = m_mapping.last().m_renderer;
 122         const RenderLayer* layer = lastRenderer->enclosingLayer();
 123
 124         // Bounds for invisible layers are intentionally not calculated, and are
 125         // therefore not necessarily expected to be correct here. This is ok,
 126         // because they will be recomputed if the layer becomes visible.
 127         if (!layer || !layer->subtreeIsInvisible()) {
 128             FloatPoint rendererMappedResult = lastRenderer->localToContainerPoint(p, container, m_mapCoordinatesFlags);
 129
 130             ASSERT(roundedIntPoint(rendererMappedResult) == roundedIntPoint(result));
 131         }
 132     }
 133 #endif
 134
 135     return result;
 136 }
 137
 138 #ifndef NDEBUG
 139 // Handy function to call from gdb while debugging mismatched point/rect errors.
 140 void RenderGeometryMap::dumpSteps() const
 141 {
 142     fprintf(stderr, "RenderGeometryMap::dumpSteps accumulatedOffset=%d,%d\n", m_accumulatedOffset.width().toInt(), m_accumulatedOffset.height().toInt());
 143     for (int i = m_mapping.size() - 1; i >= 0; --i) {
 144         fprintf(stderr, " [%d] %s: offset=%d,%d", i, m_mapping[i].m_renderer->debugName().ascii().data(), m_mapping[i].m_offset.width().toInt(), m_mapping[i].m_offset.height().toInt());
 145         if (m_mapping[i].m_hasTransform)
 146             fprintf(stderr, " hasTransform");
 147         fprintf(stderr, "\n");
 148     }
 149 }
 150 #endif
 151
 152 FloatQuad RenderGeometryMap::mapToContainer(const FloatRect& rect, const RenderLayerModelObject* container) const
 153 {
 154     FloatRect result;
 155
 156     if (!hasFixedPositionStep() && !hasTransformStep() && !hasNonUniformStep() && (!container || (m_mapping.size() && container == m_mapping[0].m_renderer))) {
 157         result = rect;
 158         result.move(m_accumulatedOffset);
 159     } else {
 160         TransformState transformState(TransformState::ApplyTransformDirection, rect.center(), rect);
 161         mapToContainer(transformState, container);
 162         result = transformState.lastPlanarQuad().boundingBox();
 163     }
 164
 165 #if ENABLE(ASSERT)
 166     if (m_mapping.size() > 0) {
 167         const RenderObject* lastRenderer = m_mapping.last().m_renderer;
 168         const RenderLayer* layer = lastRenderer->enclosingLayer();
 169
 170         // Bounds for invisible layers are intentionally not calculated, and are
 171         // therefore not necessarily expected to be correct here. This is ok,
 172         // because they will be recomputed if the layer becomes visible.
 173         if (!layer->subtreeIsInvisible() && lastRenderer->style()->visibility() == VISIBLE) {
 174             FloatRect rendererMappedResult = lastRenderer->localToContainerQuad(rect, container, m_mapCoordinatesFlags).boundingBox();
 175
 176             // Inspector creates renderers with negative width <https://bugs.webkit.org/show_bug.cgi?id=87194>.
 177             // Taking FloatQuad bounds avoids spurious assertions because of that.
 178             ASSERT(enclosingIntRect(rendererMappedResult) == enclosingIntRect(FloatQuad(result).boundingBox()));
 179         }
 180     }
 181 #endif
 182
 183     return result;
 184 }
 185
 186 void RenderGeometryMap::pushMappingsToAncestor(const RenderObject* renderer, const RenderLayerModelObject* ancestorRenderer)
 187 {
 188     // We need to push mappings in reverse order here, so do insertions rather than appends.
 189     TemporaryChange<size_t> positionChange(m_insertionPosition, m_mapping.size());
 190     do {
 191         renderer = renderer->pushMappingToContainer(ancestorRenderer, *this);
 192     } while (renderer && renderer != ancestorRenderer);
 193
 194     ASSERT(m_mapping.isEmpty() || isTopmostRenderView(m_mapping[0].m_renderer));
 195 }
 196
 197 static bool canMapBetweenRenderers(const RenderObject* renderer, const RenderObject* ancestor)
 198 {
 199     for (const RenderObject* current = renderer; ; current = current->parent()) {
 200         const RenderStyle* style = current->style();
 201         if (style->position() == FixedPosition || style->isFlippedBlocksWritingMode())
 202             return false;
 203
 204         if (current->hasColumns() || current->hasTransform() || current->isRenderFlowThread() || current->isSVGRoot())
 205             return false;
 206
 207         if (current == ancestor)
 208             break;
 209     }
 210
 211     return true;
 212 }
 213
 214 void RenderGeometryMap::pushMappingsToAncestor(const RenderLayer* layer, const RenderLayer* ancestorLayer)
 215 {
 216     const RenderObject* renderer = layer->renderer();
 217
 218     bool crossDocument = ancestorLayer && layer->renderer()->frame() != ancestorLayer->renderer()->frame();
 219     ASSERT(!crossDocument || m_mapCoordinatesFlags & TraverseDocumentBoundaries);
 220
 221     // We have to visit all the renderers to detect flipped blocks. This might defeat the gains
 222     // from mapping via layers.
 223     bool canConvertInLayerTree = (ancestorLayer && !crossDocument) ? canMapBetweenRenderers(layer->renderer(), ancestorLayer->renderer()) : false;
 224
 225 //    fprintf(stderr, "RenderGeometryMap::pushMappingsToAncestor from layer %p to layer %p, canConvertInLayerTree=%d\n", layer, ancestorLayer, canConvertInLayerTree);
 226
 227     if (canConvertInLayerTree) {
 228         LayoutPoint layerOffset;
 229         layer->convertToLayerCoords(ancestorLayer, layerOffset);
 230
 231         // The RenderView must be pushed first.
 232         if (!m_mapping.size()) {
 233             ASSERT(ancestorLayer->renderer()->isRenderView());
 234             pushMappingsToAncestor(ancestorLayer->renderer(), 0);
 235         }
 236
 237         TemporaryChange<size_t> positionChange(m_insertionPosition, m_mapping.size());
 238         bool accumulatingTransform = layer->renderer()->style()->preserves3D() || ancestorLayer->renderer()->style()->preserves3D();
 239         push(renderer, toLayoutSize(layerOffset), accumulatingTransform, /*isNonUniform*/ false, /*isFixedPosition*/ false, /*hasTransform*/ false);
 240         return;
 241     }
 242     const RenderLayerModelObject* ancestorRenderer = ancestorLayer ? ancestorLayer->renderer() : 0;
 243     pushMappingsToAncestor(renderer, ancestorRenderer);
 244 }
 245
 246 void RenderGeometryMap::push(const RenderObject* renderer, const LayoutSize& offsetFromContainer, bool accumulatingTransform, bool isNonUniform, bool isFixedPosition, bool hasTransform, LayoutSize offsetForFixedPosition)
 247 {
 248 //    fprintf(stderr, "RenderGeometryMap::push %p %d,%d isNonUniform=%d\n", renderer, offsetFromContainer.width().toInt(), offsetFromContainer.height().toInt(), isNonUniform);
 249
 250     ASSERT(m_insertionPosition != kNotFound);
 251     ASSERT(!renderer->isRenderView() || !m_insertionPosition || m_mapCoordinatesFlags & TraverseDocumentBoundaries);
 252     ASSERT(offsetForFixedPosition.isZero() || renderer->isRenderView());
 253
 254     m_mapping.insert(m_insertionPosition, RenderGeometryMapStep(renderer, accumulatingTransform, isNonUniform, isFixedPosition, hasTransform));
 255
 256     RenderGeometryMapStep& step = m_mapping[m_insertionPosition];
 257     step.m_offset = offsetFromContainer;
 258     step.m_offsetForFixedPosition = offsetForFixedPosition;
 259
 260     stepInserted(step);
 261 }
 262
 263 void RenderGeometryMap::push(const RenderObject* renderer, const TransformationMatrix& t, bool accumulatingTransform, bool isNonUniform, bool isFixedPosition, bool hasTransform, LayoutSize offsetForFixedPosition)
 264 {
 265     ASSERT(m_insertionPosition != kNotFound);
 266     ASSERT(!renderer->isRenderView() || !m_insertionPosition || m_mapCoordinatesFlags & TraverseDocumentBoundaries);
 267     ASSERT(offsetForFixedPosition.isZero() || renderer->isRenderView());
 268
 269     m_mapping.insert(m_insertionPosition, RenderGeometryMapStep(renderer, accumulatingTransform, isNonUniform, isFixedPosition, hasTransform));
 270
 271     RenderGeometryMapStep& step = m_mapping[m_insertionPosition];
 272     step.m_offsetForFixedPosition = offsetForFixedPosition;
 273
 274     if (!t.isIntegerTranslation())
 275         step.m_transform = adoptPtr(new TransformationMatrix(t));
 276     else
 277         step.m_offset = LayoutSize(t.e(), t.f());
 278
 279     stepInserted(step);
 280 }
 281
 282 void RenderGeometryMap::popMappingsToAncestor(const RenderLayerModelObject* ancestorRenderer)
 283 {
 284     ASSERT(m_mapping.size());
 285
 286     while (m_mapping.size() && m_mapping.last().m_renderer != ancestorRenderer) {
 287         stepRemoved(m_mapping.last());
 288         m_mapping.removeLast();
 289     }
 290 }
 291
 292 void RenderGeometryMap::popMappingsToAncestor(const RenderLayer* ancestorLayer)
 293 {
 294     const RenderLayerModelObject* ancestorRenderer = ancestorLayer ? ancestorLayer->renderer() : 0;
 295     popMappingsToAncestor(ancestorRenderer);
 296 }
 297
 298 void RenderGeometryMap::stepInserted(const RenderGeometryMapStep& step)
 299 {
 300     m_accumulatedOffset += step.m_offset;
 301
 302     if (step.m_isNonUniform)
 303         ++m_nonUniformStepsCount;
 304
 305     if (step.m_transform)
 306         ++m_transformedStepsCount;
 307
 308     if (step.m_isFixedPosition)
 309         ++m_fixedStepsCount;
 310 }
 311
 312 void RenderGeometryMap::stepRemoved(const RenderGeometryMapStep& step)
 313 {
 314     m_accumulatedOffset -= step.m_offset;
 315
 316     if (step.m_isNonUniform) {
 317         ASSERT(m_nonUniformStepsCount);
 318         --m_nonUniformStepsCount;
 319     }
 320
 321     if (step.m_transform) {
 322         ASSERT(m_transformedStepsCount);
 323         --m_transformedStepsCount;
 324     }
 325
 326     if (step.m_isFixedPosition) {
 327         ASSERT(m_fixedStepsCount);
 328         --m_fixedStepsCount;
 329     }
 330 }
 331
 332 #if ENABLE(ASSERT)
 333 bool RenderGeometryMap::isTopmostRenderView(const RenderObject* renderer) const
 334 {
 335     if (!renderer->isRenderView())
 336         return false;
 337
 338     // If we're not working with multiple RenderViews, then any view is considered
 339     // "topmost" (to preserve original behavior).
 340     if (!(m_mapCoordinatesFlags & TraverseDocumentBoundaries))
 341         return true;
 342
 343     return renderer->frame()->isMainFrame();
 344 }
 345 #endif
 346
 347 } // namespace blink