[svg] Add light source classes and lighting-color pres attr

https://www.w3.org/TR/SVG11/filters.html#LightSourceDefinitions

The three classes represent light source elements that will eventually
be used for feSpecularLighting and feDiffuseLighting. Currently they are
unused.

Also added the (currently unused) lighting-color presentation attribute.

Bug: skia:10841
Change-Id: Ic7824671662b8cd88cf627affc54173d5e881b7d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/359557
Commit-Queue: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>

modules/svg/include/SkSVGAttribute.h

@@ -109,6 +109,7 @@ struct SkSVGPresentationAttributes {
     SkSVGProperty<SkSVGNumberType, false> fStopOpacity;
     SkSVGProperty<SkSVGColor     , false> fFloodColor;
     SkSVGProperty<SkSVGNumberType, false> fFloodOpacity;
+    SkSVGProperty<SkSVGColor     , false> fLightingColor;
 };
 
 #endif // SkSVGAttribute_DEFINED

modules/svg/include/SkSVGFeLightSource.h

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2021 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkSVGFeLightSource_DEFINED
+#define SkSVGFeLightSource_DEFINED
+
+#include "modules/svg/include/SkSVGHiddenContainer.h"
+#include "modules/svg/include/SkSVGTypes.h"
+
+class SkSVGFeLightSource : public SkSVGHiddenContainer {
+public:
+    void appendChild(sk_sp<SkSVGNode>) final {
+        SkDebugf("cannot append child nodes to an SVG light source.\n");
+    }
+
+protected:
+    explicit SkSVGFeLightSource(SkSVGTag tag) : INHERITED(tag) {}
+
+private:
+    using INHERITED = SkSVGHiddenContainer;
+};
+
+class SkSVGFeDistantLight final : public SkSVGFeLightSource {
+public:
+    static sk_sp<SkSVGFeDistantLight> Make() {
+        return sk_sp<SkSVGFeDistantLight>(new SkSVGFeDistantLight());
+    }
+
+    SVG_ATTR(Azimuth  , SkSVGNumberType, 0)
+    SVG_ATTR(Elevation, SkSVGNumberType, 0)
+
+private:
+    SkSVGFeDistantLight() : INHERITED(SkSVGTag::kFeDistantLight) {}
+
+    bool parseAndSetAttribute(const char*, const char*) override;
+
+    using INHERITED = SkSVGFeLightSource;
+};
+
+class SkSVGFePointLight final : public SkSVGFeLightSource {
+public:
+    static sk_sp<SkSVGFePointLight> Make() {
+        return sk_sp<SkSVGFePointLight>(new SkSVGFePointLight());
+    }
+
+    SVG_ATTR(X, SkSVGNumberType, 0)
+    SVG_ATTR(Y, SkSVGNumberType, 0)
+    SVG_ATTR(Z, SkSVGNumberType, 0)
+
+private:
+    SkSVGFePointLight() : INHERITED(SkSVGTag::kFePointLight) {}
+
+    bool parseAndSetAttribute(const char*, const char*) override;
+
+    using INHERITED = SkSVGFeLightSource;
+};
+
+class SkSVGFeSpotLight final : public SkSVGFeLightSource {
+public:
+    static sk_sp<SkSVGFeSpotLight> Make() {
+        return sk_sp<SkSVGFeSpotLight>(new SkSVGFeSpotLight());
+    }
+
+    SVG_ATTR(X               , SkSVGNumberType, 0)
+    SVG_ATTR(Y               , SkSVGNumberType, 0)
+    SVG_ATTR(Z               , SkSVGNumberType, 0)
+    SVG_ATTR(PointsAtX       , SkSVGNumberType, 0)
+    SVG_ATTR(PointsAtY       , SkSVGNumberType, 0)
+    SVG_ATTR(PointsAtZ       , SkSVGNumberType, 0)
+    SVG_ATTR(SpecularExponent, SkSVGNumberType, 1)
+
+    SVG_OPTIONAL_ATTR(LimitingConeAngle, SkSVGNumberType)
+
+private:
+    SkSVGFeSpotLight() : INHERITED(SkSVGTag::kFeSpotLight) {}
+
+    bool parseAndSetAttribute(const char*, const char*) override;
+
+    using INHERITED = SkSVGFeLightSource;
+};
+
+#endif  // SkSVGFeLightSource_DEFINED

modules/svg/include/SkSVGNode.h

@@ -29,10 +29,13 @@ enum class SkSVGTag {
     kFeColorMatrix,
     kFeComposite,
     kFeDisplacementMap,
+    kFeDistantLight,
     kFeFlood,
     kFeGaussianBlur,
     kFeMorphology,
     kFeOffset,
+    kFePointLight,
+    kFeSpotLight,
     kFeTurbulence,
     kFilter,
     kG,
@@ -136,6 +139,7 @@ public:
     SVG_PRES_ATTR(StopOpacity              , SkSVGNumberType, false)
     SVG_PRES_ATTR(FloodColor               , SkSVGColor     , false)
     SVG_PRES_ATTR(FloodOpacity             , SkSVGNumberType, false)
+    SVG_PRES_ATTR(LightingColor            , SkSVGColor     , false)
 
 protected:
     SkSVGNode(SkSVGTag);

modules/svg/src/SkSVGAttribute.cpp

@@ -40,6 +40,7 @@ SkSVGPresentationAttributes SkSVGPresentationAttributes::MakeInitial() {
     result.fStopOpacity.set(SkSVGNumberType(1));
     result.fFloodColor.set(SkSVGColor(SK_ColorBLACK));
     result.fFloodOpacity.set(SkSVGNumberType(1));
+    result.fLightingColor.set(SkSVGColor(SK_ColorWHITE));
 
     return result;
 }

modules/svg/src/SkSVGDOM.cpp

@@ -22,6 +22,7 @@
 #include "modules/svg/include/SkSVGFeDisplacementMap.h"
 #include "modules/svg/include/SkSVGFeFlood.h"
 #include "modules/svg/include/SkSVGFeGaussianBlur.h"
+#include "modules/svg/include/SkSVGFeLightSource.h"
 #include "modules/svg/include/SkSVGFeMorphology.h"
 #include "modules/svg/include/SkSVGFeOffset.h"
 #include "modules/svg/include/SkSVGFeTurbulence.h"
@@ -266,11 +267,14 @@ SortedDictionaryEntry<sk_sp<SkSVGNode>(*)()> gTagFactories[] = {
     { "feBlend"          , []() -> sk_sp<SkSVGNode> { return SkSVGFeBlend::Make();           }},
     { "feColorMatrix"    , []() -> sk_sp<SkSVGNode> { return SkSVGFeColorMatrix::Make();     }},
     { "feComposite"      , []() -> sk_sp<SkSVGNode> { return SkSVGFeComposite::Make();       }},
+    { "feDistantLight"   , []() -> sk_sp<SkSVGNode> { return SkSVGFeDistantLight::Make();    }},
     { "feDisplacementMap", []() -> sk_sp<SkSVGNode> { return SkSVGFeDisplacementMap::Make(); }},
     { "feFlood"          , []() -> sk_sp<SkSVGNode> { return SkSVGFeFlood::Make();           }},
     { "feGaussianBlur"   , []() -> sk_sp<SkSVGNode> { return SkSVGFeGaussianBlur::Make();    }},
     { "feMorphology"     , []() -> sk_sp<SkSVGNode> { return SkSVGFeMorphology::Make();      }},
     { "feOffset"         , []() -> sk_sp<SkSVGNode> { return SkSVGFeOffset::Make();          }},
+    { "fePointLight"     , []() -> sk_sp<SkSVGNode> { return SkSVGFePointLight::Make();      }},
+    { "feSpotLight"      , []() -> sk_sp<SkSVGNode> { return SkSVGFeSpotLight::Make();       }},
     { "feTurbulence"     , []() -> sk_sp<SkSVGNode> { return SkSVGFeTurbulence::Make();      }},
     { "filter"           , []() -> sk_sp<SkSVGNode> { return SkSVGFilter::Make();            }},
     { "g"                , []() -> sk_sp<SkSVGNode> { return SkSVGG::Make();                 }},

modules/svg/src/SkSVGFeLightSource.cpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2021 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "modules/svg/include/SkSVGAttributeParser.h"
+#include "modules/svg/include/SkSVGFeLightSource.h"
+#include "modules/svg/include/SkSVGValue.h"
+
+bool SkSVGFeDistantLight::parseAndSetAttribute(const char* n, const char* v) {
+    return INHERITED::parseAndSetAttribute(n, v) ||
+           this->setAzimuth(SkSVGAttributeParser::parse<SkSVGNumberType>("azimuth", n, v)) ||
+           this->setElevation(SkSVGAttributeParser::parse<SkSVGNumberType>("elevation", n, v));
+}
+
+bool SkSVGFePointLight::parseAndSetAttribute(const char* n, const char* v) {
+    return INHERITED::parseAndSetAttribute(n, v) ||
+           this->setX(SkSVGAttributeParser::parse<SkSVGNumberType>("x", n, v)) ||
+           this->setY(SkSVGAttributeParser::parse<SkSVGNumberType>("y", n, v)) ||
+           this->setZ(SkSVGAttributeParser::parse<SkSVGNumberType>("z", n, v));
+}
+
+bool SkSVGFeSpotLight::parseAndSetAttribute(const char* n, const char* v) {
+    return INHERITED::parseAndSetAttribute(n, v) ||
+           this->setX(SkSVGAttributeParser::parse<SkSVGNumberType>("x", n, v)) ||
+           this->setY(SkSVGAttributeParser::parse<SkSVGNumberType>("y", n, v)) ||
+           this->setZ(SkSVGAttributeParser::parse<SkSVGNumberType>("z", n, v)) ||
+           this->setPointsAtX(SkSVGAttributeParser::parse<SkSVGNumberType>("pointsAtX", n, v)) ||
+           this->setPointsAtY(SkSVGAttributeParser::parse<SkSVGNumberType>("pointsAtY", n, v)) ||
+           this->setPointsAtZ(SkSVGAttributeParser::parse<SkSVGNumberType>("pointsAtZ", n, v)) ||
+           this->setSpecularExponent(
+                   SkSVGAttributeParser::parse<SkSVGNumberType>("specularExponent", n, v)) ||
+           this->setLimitingConeAngle(
+                   SkSVGAttributeParser::parse<SkSVGNumberType>("limitingConeAngle", n, v));
+}

modules/svg/src/SkSVGNode.cpp

@@ -20,6 +20,7 @@ SkSVGNode::SkSVGNode(SkSVGTag t) : fTag(t) {
     fPresentationAttributes.fStopOpacity.set(SkSVGNumberType(1.0f));
     fPresentationAttributes.fFloodColor.set(SkSVGColor(SK_ColorBLACK));
     fPresentationAttributes.fFloodOpacity.set(SkSVGNumberType(1.0f));
+    fPresentationAttributes.fLightingColor.set(SkSVGColor(SK_ColorWHITE));
 }
 
 SkSVGNode::~SkSVGNode() { }
@@ -103,6 +104,7 @@ bool SkSVGNode::parseAndSetAttribute(const char* n, const char* v) {
            || PARSE_AND_SET("font-size"                  , FontSize)
            || PARSE_AND_SET("font-style"                 , FontStyle)
            || PARSE_AND_SET("font-weight"                , FontWeight)
+           || PARSE_AND_SET("lighting-color"             , LightingColor)
            || PARSE_AND_SET("mask"                       , Mask)
            || PARSE_AND_SET("opacity"                    , Opacity)
            || PARSE_AND_SET("stop-color"                 , StopColor)

modules/svg/src/SkSVGRenderContext.cpp

@@ -254,6 +254,7 @@ void SkSVGRenderContext::applyPresentationAttributes(const SkSVGPresentationAttr
     // - stop-opacity
     // - flood-color
     // - flood-opacity
+    // - lighting-color
 }
 
 void SkSVGRenderContext::applyOpacity(SkScalar opacity, uint32_t flags, bool hasFilter) {

modules/svg/svg.gni

@@ -23,6 +23,7 @@ skia_svg_public = [
   "$_include/SkSVGFeDisplacementMap.h",
   "$_include/SkSVGFeFlood.h",
   "$_include/SkSVGFeGaussianBlur.h",
+  "$_include/SkSVGFeLightSource.h",
   "$_include/SkSVGFeMorphology.h",
   "$_include/SkSVGFeOffset.h",
   "$_include/SkSVGFeTurbulence.h",
@@ -67,6 +68,7 @@ skia_svg_sources = [
   "$_src/SkSVGFeDisplacementMap.cpp",
   "$_src/SkSVGFeFlood.cpp",
   "$_src/SkSVGFeGaussianBlur.cpp",
+  "$_src/SkSVGFeLightSource.cpp",
   "$_src/SkSVGFeMorphology.cpp",
   "$_src/SkSVGFeOffset.cpp",
   "$_src/SkSVGFeTurbulence.cpp",