Split SVGFilterbuilder into "builder" and "node map" parts

third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp

Index: third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp
diff --git a/third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp b/third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp
index a032ced8955bf4a00af58d009d31da8dca2896f4..87e424b78dbe86629a4fc3c8c22e641c9743d749 100644
--- a/third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp
+++ b/third_party/WebKit/Source/core/svg/graphics/filters/SVGFilterBuilder.cpp
@@ -20,30 +20,130 @@
 #include "config.h"
 #include "core/svg/graphics/filters/SVGFilterBuilder.h"
 
+#include "core/css/CSSPrimitiveValue.h"
+#include "core/css/CSSPrimitiveValueMappings.h"
+#include "core/css/StylePropertySet.h"
+#include "core/dom/ElementTraversal.h"
+#include "core/layout/LayoutObject.h"
+#include "core/svg/SVGFilterElement.h"
+#include "core/svg/SVGFilterPrimitiveStandardAttributes.h"
+#include "platform/graphics/filters/Filter.h"
 #include "platform/graphics/filters/SourceAlpha.h"
 #include "platform/graphics/filters/SourceGraphic.h"
 
 namespace blink {
 
-SVGFilterBuilder::SVGFilterBuilder(PassRefPtrWillBeRawPtr<FilterEffect> sourceGraphic)
+void SVGFilterGraphNodeMap::addBuiltinEffect(FilterEffect* effect)
 {
-    RefPtrWillBeRawPtr<FilterEffect> sourceGraphicRef = sourceGraphic;
-    m_builtinEffects.add(SourceGraphic::effectName(), sourceGraphicRef);
-    m_builtinEffects.add(SourceAlpha::effectName(), SourceAlpha::create(sourceGraphicRef.get()));
-    addBuiltinEffects();
+    m_effectReferences.add(effect, FilterEffectSet());
+}
+
+void SVGFilterGraphNodeMap::addPrimitive(PassRefPtrWillBeRawPtr<FilterEffect> prpEffect, LayoutObject* object)
+{
+    RefPtrWillBeRawPtr<FilterEffect> effect = prpEffect;
+
+    // The effect must be a newly created filter effect.
+    ASSERT(!m_effectReferences.contains(effect));
+    ASSERT(object && !m_effectRenderer.contains(object));
+    m_effectReferences.add(effect, FilterEffectSet());
+
+    unsigned numberOfInputEffects = effect->inputEffects().size();
+
+    // Add references from the inputs of this effect to the effect itself, to
+    // allow determining what effects needs to be invalidated when a certain
+    // effect changes.
+    for (unsigned i = 0; i < numberOfInputEffects; ++i)
+        effectReferences(effect->inputEffect(i)).add(effect.get());
+
+    m_effectRenderer.add(object, effect.get());
 }
 
-DEFINE_TRACE(SVGFilterBuilder)
+void SVGFilterGraphNodeMap::invalidateDependentEffects(FilterEffect* effect)
+{
+    if (!effect->hasImageFilter())
+        return;
+
+    effect->clearResult();
+
+    FilterEffectSet& effectReferences = this->effectReferences(effect);
+    for (FilterEffect* effectReference : effectReferences)
+        invalidateDependentEffects(effectReference);
+}
+
+DEFINE_TRACE(SVGFilterGraphNodeMap)
 {
 #if ENABLE(OILPAN)
-    visitor->trace(m_builtinEffects);
-    visitor->trace(m_namedEffects);
     visitor->trace(m_effectRenderer);
     visitor->trace(m_effectReferences);
-    visitor->trace(m_lastEffect);
 #endif
 }
 
+SVGFilterBuilder::SVGFilterBuilder(
+    PassRefPtrWillBeRawPtr<Filter> filter,
+    PassRefPtrWillBeRawPtr<FilterEffect> sourceGraphic,
+    PassRefPtrWillBeRawPtr<SVGFilterGraphNodeMap> nodeMap)
+    : m_filter(filter)
+    , m_nodeMap(nodeMap)
+{
+    RefPtrWillBeRawPtr<FilterEffect> sourceGraphicRef = sourceGraphic;
+    m_builtinEffects.add(SourceGraphic::effectName(), sourceGraphicRef);
+    m_builtinEffects.add(SourceAlpha::effectName(), SourceAlpha::create(sourceGraphicRef.get()));
+    addBuiltinEffects();
+}
+
+void SVGFilterBuilder::addBuiltinEffects()
+{
+    if (!m_nodeMap)
+        return;
+    for (const auto& entry : m_builtinEffects)
+        m_nodeMap->addBuiltinEffect(entry.value.get());
+}
+
+// Returns the color-interpolation-filters property of the element.
+static EColorInterpolation colorInterpolationForElement(SVGElement& element, EColorInterpolation parentColorInterpolation)
+{
+    if (const LayoutObject* layoutObject = element.layoutObject())
+        return layoutObject->styleRef().svgStyle().colorInterpolationFilters();
+
+    // No layout has been performed, try to determine the property value
+    // "manually" (used by external SVG files.)
+    if (const StylePropertySet* propertySet = element.presentationAttributeStyle()) {
+        RefPtrWillBeRawPtr<CSSValue> cssValue = propertySet->getPropertyCSSValue(CSSPropertyColorInterpolationFilters);
+        if (cssValue && cssValue->isPrimitiveValue()) {
+            const CSSPrimitiveValue& primitiveValue = *((CSSPrimitiveValue*)cssValue.get());
+            return static_cast<EColorInterpolation>(primitiveValue);
+        }
+    }
+    // 'auto' is the default (per Filter Effects), but since the property is
+    // inherited, propagate the parent's value.
+    return parentColorInterpolation;
+}
+
+void SVGFilterBuilder::buildGraph(SVGFilterElement& filterElement, const FloatRect& referenceBox)
+{
+    EColorInterpolation filterColorInterpolation = colorInterpolationForElement(filterElement, CI_AUTO);
+
+    for (SVGElement* element = Traversal<SVGElement>::firstChild(filterElement); element; element = Traversal<SVGElement>::nextSibling(*element)) {
+        if (!element->isFilterEffect())
+            continue;
+
+        SVGFilterPrimitiveStandardAttributes* effectElement = static_cast<SVGFilterPrimitiveStandardAttributes*>(element);
+        RefPtrWillBeRawPtr<FilterEffect> effect = effectElement->build(this, m_filter.get());
+        if (!effect)
+            continue;
+
+        if (m_nodeMap && effectElement->layoutObject())
+            m_nodeMap->addPrimitive(effect, effectElement->layoutObject());
+        effectElement->setStandardAttributes(effect.get());
+        effect->setEffectBoundaries(SVGLengthContext::resolveRectangle<SVGFilterPrimitiveStandardAttributes>(effectElement, filterElement.primitiveUnits()->currentValue()->enumValue(), referenceBox));
+        EColorInterpolation colorInterpolation = colorInterpolationForElement(*effectElement, filterColorInterpolation);
+        effect->setOperatingColorSpace(colorInterpolation == CI_LINEARRGB ? ColorSpaceLinearRGB : ColorSpaceDeviceRGB);
+
+        add(AtomicString(effectElement->result()->currentValue()->value()), effect);
+    }
+    m_filter->setLastEffect(m_lastEffect);

[Stephen White, 2015/10/07 19:44:01]

It seems a shame to add the Filter as a member of SVGFilterBuilder, if its only
purpose is to call setLastEffect() on it. Could we do this outside the builder?

[fs, 2015/10/08 10:53:11]

We still need it so that we can pass it to SVGFE*Element::build(...) though. I
change it to be an argument of buildGraph instead, sinking the setLastEffect
call out into callers. Better? (For disclosure, I was going to just drop the
Filter* to SVGFE*Element::build(...) and let them read it from the passed
builder instead - I do agree it's hanging pretty loose though...)

[Stephen White, 2015/10/08 18:48:03]

Ah yes, I missed that. Definitely better as an arg.

+}
+
 void SVGFilterBuilder::add(const AtomicString& id, PassRefPtrWillBeRawPtr<FilterEffect> effect)
 {
     if (id.isEmpty()) {
@@ -74,42 +174,4 @@ FilterEffect* SVGFilterBuilder::getEffectById(const AtomicString& id) const
     return m_builtinEffects.get(SourceGraphic::effectName());
 }
 
-void SVGFilterBuilder::appendEffectToEffectReferences(PassRefPtrWillBeRawPtr<FilterEffect> prpEffect, LayoutObject* object)
-{
-    RefPtrWillBeRawPtr<FilterEffect> effect = prpEffect;
-
-    // The effect must be a newly created filter effect.
-    ASSERT(!m_effectReferences.contains(effect));
-    ASSERT(object && !m_effectRenderer.contains(object));
-    m_effectReferences.add(effect, FilterEffectSet());
-
-    unsigned numberOfInputEffects = effect->inputEffects().size();
-
-    // It is not possible to add the same value to a set twice.
-    for (unsigned i = 0; i < numberOfInputEffects; ++i)
-        effectReferences(effect->inputEffect(i)).add(effect.get());
-    m_effectRenderer.add(object, effect.get());
-}
-
-void SVGFilterBuilder::clearEffects()
-{
-    m_lastEffect = nullptr;
-    m_namedEffects.clear();
-    m_effectReferences.clear();
-    m_effectRenderer.clear();
-    addBuiltinEffects();
-}
-
-void SVGFilterBuilder::clearResultsRecursive(FilterEffect* effect)
-{
-    if (!effect->hasImageFilter())
-        return;
-
-    effect->clearResult();
-
-    FilterEffectSet& effectReferences = this->effectReferences(effect);
-    for (FilterEffect* effectReference : effectReferences)
-        clearResultsRecursive(effectReference);
-}
-
 } // namespace blink