1 /*
2 * Copyright 2020 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "modules/svg/include/SkSVGFeLighting.h"
9
10 #include "include/core/SkImageFilter.h"
11 #include "include/core/SkM44.h"
12 #include "include/core/SkPoint3.h"
13 #include "include/effects/SkImageFilters.h"
14 #include "include/private/base/SkDebug.h"
15 #include "include/private/base/SkTArray.h"
16 #include "modules/svg/include/SkSVGAttributeParser.h"
17 #include "modules/svg/include/SkSVGFeLightSource.h"
18 #include "modules/svg/include/SkSVGFilterContext.h"
19 #include "modules/svg/include/SkSVGRenderContext.h"
20
parseAndSetAttribute(const char * n,const char * v)21 bool SkSVGFeLighting::parseAndSetAttribute(const char* n, const char* v) {
22 return INHERITED::parseAndSetAttribute(n, v) ||
23 this->setSurfaceScale(
24 SkSVGAttributeParser::parse<SkSVGNumberType>("surfaceScale", n, v)) ||
25 this->setKernelUnitLength(SkSVGAttributeParser::parse<SkSVGFeLighting::KernelUnitLength>(
26 "kernelUnitLength", n, v));
27 }
28
29 template <>
parse(SkSVGFeLighting::KernelUnitLength * kernelUnitLength)30 bool SkSVGAttributeParser::parse<SkSVGFeLighting::KernelUnitLength>(
31 SkSVGFeLighting::KernelUnitLength* kernelUnitLength) {
32 std::vector<SkSVGNumberType> values;
33 if (!this->parse(&values)) {
34 return false;
35 }
36
37 kernelUnitLength->fDx = values[0];
38 kernelUnitLength->fDy = values.size() > 1 ? values[1] : values[0];
39 return true;
40 }
41
onMakeImageFilter(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx) const42 sk_sp<SkImageFilter> SkSVGFeLighting::onMakeImageFilter(const SkSVGRenderContext& ctx,
43 const SkSVGFilterContext& fctx) const {
44 for (const auto& child : fChildren) {
45 switch (child->tag()) {
46 case SkSVGTag::kFeDistantLight:
47 return this->makeDistantLight(
48 ctx, fctx, static_cast<const SkSVGFeDistantLight*>(child.get()));
49 case SkSVGTag::kFePointLight:
50 return this->makePointLight(
51 ctx, fctx, static_cast<const SkSVGFePointLight*>(child.get()));
52 case SkSVGTag::kFeSpotLight:
53 return this->makeSpotLight(
54 ctx, fctx, static_cast<const SkSVGFeSpotLight*>(child.get()));
55 default:
56 // Ignore unknown children, such as <desc> elements
57 break;
58 }
59 }
60
61 SkDEBUGF("lighting filter effect needs exactly one light source\n");
62 return nullptr;
63 }
64
resolveLightingColor(const SkSVGRenderContext & ctx) const65 SkColor SkSVGFeLighting::resolveLightingColor(const SkSVGRenderContext& ctx) const {
66 const auto color = this->getLightingColor();
67 if (!color.isValue()) {
68 // Uninherited presentation attributes should have a concrete value by now.
69 SkDEBUGF("unhandled: lighting-color has no value\n");
70 return SK_ColorWHITE;
71 }
72
73 return ctx.resolveSvgColor(*color);
74 }
75
resolveXYZ(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,SkSVGNumberType x,SkSVGNumberType y,SkSVGNumberType z) const76 SkPoint3 SkSVGFeLighting::resolveXYZ(const SkSVGRenderContext& ctx,
77 const SkSVGFilterContext& fctx,
78 SkSVGNumberType x,
79 SkSVGNumberType y,
80 SkSVGNumberType z) const {
81 const auto obbt = ctx.transformForCurrentOBB(fctx.primitiveUnits());
82 const auto xy = SkV2{x,y} * obbt.scale + obbt.offset;
83 z = SkSVGLengthContext({obbt.scale.x, obbt.scale.y})
84 .resolve(SkSVGLength(z * 100.f, SkSVGLength::Unit::kPercentage),
85 SkSVGLengthContext::LengthType::kOther);
86 return SkPoint3::Make(xy.x, xy.y, z);
87 }
88
parseAndSetAttribute(const char * n,const char * v)89 bool SkSVGFeSpecularLighting::parseAndSetAttribute(const char* n, const char* v) {
90 return INHERITED::parseAndSetAttribute(n, v) ||
91 this->setSpecularConstant(
92 SkSVGAttributeParser::parse<SkSVGNumberType>("specularConstant", n, v)) ||
93 this->setSpecularExponent(
94 SkSVGAttributeParser::parse<SkSVGNumberType>("specularExponent", n, v));
95 }
96
makeDistantLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFeDistantLight * light) const97 sk_sp<SkImageFilter> SkSVGFeSpecularLighting::makeDistantLight(
98 const SkSVGRenderContext& ctx,
99 const SkSVGFilterContext& fctx,
100 const SkSVGFeDistantLight* light) const {
101 const SkPoint3 dir = light->computeDirection();
102 return SkImageFilters::DistantLitSpecular(
103 this->resolveXYZ(ctx, fctx, dir.fX, dir.fY, dir.fZ),
104 this->resolveLightingColor(ctx),
105 this->getSurfaceScale(),
106 fSpecularConstant,
107 fSpecularExponent,
108 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
109 this->resolveFilterSubregion(ctx, fctx));
110 }
111
makePointLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFePointLight * light) const112 sk_sp<SkImageFilter> SkSVGFeSpecularLighting::makePointLight(const SkSVGRenderContext& ctx,
113 const SkSVGFilterContext& fctx,
114 const SkSVGFePointLight* light) const {
115 return SkImageFilters::PointLitSpecular(
116 this->resolveXYZ(ctx, fctx, light->getX(), light->getY(), light->getZ()),
117 this->resolveLightingColor(ctx),
118 this->getSurfaceScale(),
119 fSpecularConstant,
120 fSpecularExponent,
121 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
122 this->resolveFilterSubregion(ctx, fctx));
123 }
124
makeSpotLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFeSpotLight * light) const125 sk_sp<SkImageFilter> SkSVGFeSpecularLighting::makeSpotLight(const SkSVGRenderContext& ctx,
126 const SkSVGFilterContext& fctx,
127 const SkSVGFeSpotLight* light) const {
128 const auto& limitingConeAngle = light->getLimitingConeAngle();
129 const float cutoffAngle = limitingConeAngle.isValid() ? *limitingConeAngle : 180.f;
130
131 return SkImageFilters::SpotLitSpecular(
132 this->resolveXYZ(ctx, fctx, light->getX(), light->getY(), light->getZ()),
133 this->resolveXYZ(
134 ctx, fctx, light->getPointsAtX(), light->getPointsAtY(), light->getPointsAtZ()),
135 light->getSpecularExponent(),
136 cutoffAngle,
137 this->resolveLightingColor(ctx),
138 this->getSurfaceScale(),
139 fSpecularConstant,
140 fSpecularExponent,
141 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
142 this->resolveFilterSubregion(ctx, fctx));
143 }
144
parseAndSetAttribute(const char * n,const char * v)145 bool SkSVGFeDiffuseLighting::parseAndSetAttribute(const char* n, const char* v) {
146 return INHERITED::parseAndSetAttribute(n, v) ||
147 this->setDiffuseConstant(
148 SkSVGAttributeParser::parse<SkSVGNumberType>("diffuseConstant", n, v));
149 }
150
makeDistantLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFeDistantLight * light) const151 sk_sp<SkImageFilter> SkSVGFeDiffuseLighting::makeDistantLight(
152 const SkSVGRenderContext& ctx,
153 const SkSVGFilterContext& fctx,
154 const SkSVGFeDistantLight* light) const {
155 const SkPoint3 dir = light->computeDirection();
156 return SkImageFilters::DistantLitDiffuse(
157 this->resolveXYZ(ctx, fctx, dir.fX, dir.fY, dir.fZ),
158 this->resolveLightingColor(ctx),
159 this->getSurfaceScale(),
160 this->getDiffuseConstant(),
161 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
162 this->resolveFilterSubregion(ctx, fctx));
163 }
164
makePointLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFePointLight * light) const165 sk_sp<SkImageFilter> SkSVGFeDiffuseLighting::makePointLight(const SkSVGRenderContext& ctx,
166 const SkSVGFilterContext& fctx,
167 const SkSVGFePointLight* light) const {
168 return SkImageFilters::PointLitDiffuse(
169 this->resolveXYZ(ctx, fctx, light->getX(), light->getY(), light->getZ()),
170 this->resolveLightingColor(ctx),
171 this->getSurfaceScale(),
172 this->getDiffuseConstant(),
173 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
174 this->resolveFilterSubregion(ctx, fctx));
175 }
176
makeSpotLight(const SkSVGRenderContext & ctx,const SkSVGFilterContext & fctx,const SkSVGFeSpotLight * light) const177 sk_sp<SkImageFilter> SkSVGFeDiffuseLighting::makeSpotLight(const SkSVGRenderContext& ctx,
178 const SkSVGFilterContext& fctx,
179 const SkSVGFeSpotLight* light) const {
180 const auto& limitingConeAngle = light->getLimitingConeAngle();
181 const float cutoffAngle = limitingConeAngle.isValid() ? *limitingConeAngle : 180.f;
182
183 return SkImageFilters::SpotLitDiffuse(
184 this->resolveXYZ(ctx, fctx, light->getX(), light->getY(), light->getZ()),
185 this->resolveXYZ(
186 ctx, fctx, light->getPointsAtX(), light->getPointsAtY(), light->getPointsAtZ()),
187 light->getSpecularExponent(),
188 cutoffAngle,
189 this->resolveLightingColor(ctx),
190 this->getSurfaceScale(),
191 this->getDiffuseConstant(),
192 fctx.resolveInput(ctx, this->getIn(), this->resolveColorspace(ctx, fctx)),
193 this->resolveFilterSubregion(ctx, fctx));
194 }
195