1 /*
2 * Copyright 2016 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 "include/core/SkCanvas.h"
9 #include "include/core/SkMatrix.h"
10 #include "include/pathops/SkPathOps.h"
11 #include "include/private/base/SkTPin.h"
12 #include "modules/svg/include/SkSVGNode.h"
13 #include "modules/svg/include/SkSVGRenderContext.h"
14 #include "modules/svg/include/SkSVGValue.h"
15 #include "src/base/SkTLazy.h"
16
SkSVGNode(SkSVGTag t)17 SkSVGNode::SkSVGNode(SkSVGTag t) : fTag(t) {
18 // Uninherited presentation attributes need a non-null default value.
19 fPresentationAttributes.fStopColor.set(SkSVGColor(SK_ColorBLACK));
20 fPresentationAttributes.fStopOpacity.set(SkSVGNumberType(1.0f));
21 fPresentationAttributes.fFloodColor.set(SkSVGColor(SK_ColorBLACK));
22 fPresentationAttributes.fFloodOpacity.set(SkSVGNumberType(1.0f));
23 fPresentationAttributes.fLightingColor.set(SkSVGColor(SK_ColorWHITE));
24 }
25
~SkSVGNode()26 SkSVGNode::~SkSVGNode() { }
27
render(const SkSVGRenderContext & ctx) const28 void SkSVGNode::render(const SkSVGRenderContext& ctx) const {
29 SkSVGRenderContext localContext(ctx, this);
30
31 if (this->onPrepareToRender(&localContext)) {
32 this->onRender(localContext);
33 }
34 }
35
asPaint(const SkSVGRenderContext & ctx,SkPaint * paint) const36 bool SkSVGNode::asPaint(const SkSVGRenderContext& ctx, SkPaint* paint) const {
37 SkSVGRenderContext localContext(ctx);
38
39 return this->onPrepareToRender(&localContext) && this->onAsPaint(localContext, paint);
40 }
41
asPath(const SkSVGRenderContext & ctx) const42 SkPath SkSVGNode::asPath(const SkSVGRenderContext& ctx) const {
43 SkSVGRenderContext localContext(ctx);
44 if (!this->onPrepareToRender(&localContext)) {
45 return SkPath();
46 }
47
48 SkPath path = this->onAsPath(localContext);
49
50 if (const auto* clipPath = localContext.clipPath()) {
51 // There is a clip-path present on the current node.
52 Op(path, *clipPath, kIntersect_SkPathOp, &path);
53 }
54
55 return path;
56 }
57
objectBoundingBox(const SkSVGRenderContext & ctx) const58 SkRect SkSVGNode::objectBoundingBox(const SkSVGRenderContext& ctx) const {
59 return this->onObjectBoundingBox(ctx);
60 }
61
onPrepareToRender(SkSVGRenderContext * ctx) const62 bool SkSVGNode::onPrepareToRender(SkSVGRenderContext* ctx) const {
63 ctx->applyPresentationAttributes(fPresentationAttributes,
64 this->hasChildren() ? 0 : SkSVGRenderContext::kLeaf);
65
66 // visibility:hidden and display:none disable rendering.
67 // TODO: if display is not a value (true when display="inherit"), we currently
68 // ignore it. Eventually we should be able to add SkASSERT(display.isValue()).
69 const auto visibility = ctx->presentationContext().fInherited.fVisibility->type();
70 const auto display = fPresentationAttributes.fDisplay; // display is uninherited
71 return visibility != SkSVGVisibility::Type::kHidden &&
72 (!display.isValue() || *display != SkSVGDisplay::kNone);
73 }
74
setAttribute(SkSVGAttribute attr,const SkSVGValue & v)75 void SkSVGNode::setAttribute(SkSVGAttribute attr, const SkSVGValue& v) {
76 this->onSetAttribute(attr, v);
77 }
78
79 template <typename T>
SetInheritedByDefault(SkTLazy<T> & presentation_attribute,const T & value)80 void SetInheritedByDefault(SkTLazy<T>& presentation_attribute, const T& value) {
81 if (value.type() != T::Type::kInherit) {
82 presentation_attribute.set(value);
83 } else {
84 // kInherited values are semantically equivalent to
85 // the absence of a local presentation attribute.
86 presentation_attribute.reset();
87 }
88 }
89
parseAndSetAttribute(const char * n,const char * v)90 bool SkSVGNode::parseAndSetAttribute(const char* n, const char* v) {
91 #define PARSE_AND_SET(svgName, attrName) \
92 this->set##attrName( \
93 SkSVGAttributeParser::parseProperty<decltype(fPresentationAttributes.f##attrName)>( \
94 svgName, n, v))
95
96 return PARSE_AND_SET( "clip-path" , ClipPath)
97 || PARSE_AND_SET("clip-rule" , ClipRule)
98 || PARSE_AND_SET("color" , Color)
99 || PARSE_AND_SET("color-interpolation" , ColorInterpolation)
100 || PARSE_AND_SET("color-interpolation-filters", ColorInterpolationFilters)
101 || PARSE_AND_SET("display" , Display)
102 || PARSE_AND_SET("fill" , Fill)
103 || PARSE_AND_SET("fill-opacity" , FillOpacity)
104 || PARSE_AND_SET("fill-rule" , FillRule)
105 || PARSE_AND_SET("filter" , Filter)
106 || PARSE_AND_SET("flood-color" , FloodColor)
107 || PARSE_AND_SET("flood-opacity" , FloodOpacity)
108 || PARSE_AND_SET("font-family" , FontFamily)
109 || PARSE_AND_SET("font-size" , FontSize)
110 || PARSE_AND_SET("font-style" , FontStyle)
111 || PARSE_AND_SET("font-weight" , FontWeight)
112 || PARSE_AND_SET("lighting-color" , LightingColor)
113 || PARSE_AND_SET("mask" , Mask)
114 || PARSE_AND_SET("opacity" , Opacity)
115 || PARSE_AND_SET("stop-color" , StopColor)
116 || PARSE_AND_SET("stop-opacity" , StopOpacity)
117 || PARSE_AND_SET("stroke" , Stroke)
118 || PARSE_AND_SET("stroke-dasharray" , StrokeDashArray)
119 || PARSE_AND_SET("stroke-dashoffset" , StrokeDashOffset)
120 || PARSE_AND_SET("stroke-linecap" , StrokeLineCap)
121 || PARSE_AND_SET("stroke-linejoin" , StrokeLineJoin)
122 || PARSE_AND_SET("stroke-miterlimit" , StrokeMiterLimit)
123 || PARSE_AND_SET("stroke-opacity" , StrokeOpacity)
124 || PARSE_AND_SET("stroke-width" , StrokeWidth)
125 || PARSE_AND_SET("text-anchor" , TextAnchor)
126 || PARSE_AND_SET("visibility" , Visibility);
127
128 #undef PARSE_AND_SET
129 }
130
131 // https://www.w3.org/TR/SVG11/coords.html#PreserveAspectRatioAttribute
ComputeViewboxMatrix(const SkRect & viewBox,const SkRect & viewPort,SkSVGPreserveAspectRatio par)132 SkMatrix SkSVGNode::ComputeViewboxMatrix(const SkRect& viewBox,
133 const SkRect& viewPort,
134 SkSVGPreserveAspectRatio par) {
135 if (viewBox.isEmpty() || viewPort.isEmpty()) {
136 return SkMatrix::Scale(0, 0);
137 }
138
139 auto compute_scale = [&]() -> SkV2 {
140 const auto sx = viewPort.width() / viewBox.width(),
141 sy = viewPort.height() / viewBox.height();
142
143 if (par.fAlign == SkSVGPreserveAspectRatio::kNone) {
144 // none -> anisotropic scaling, regardless of fScale
145 return {sx, sy};
146 }
147
148 // isotropic scaling
149 const auto s = par.fScale == SkSVGPreserveAspectRatio::kMeet
150 ? std::min(sx, sy)
151 : std::max(sx, sy);
152 return {s, s};
153 };
154
155 auto compute_trans = [&](const SkV2& scale) -> SkV2 {
156 static constexpr float gAlignCoeffs[] = {
157 0.0f, // Min
158 0.5f, // Mid
159 1.0f // Max
160 };
161
162 const size_t x_coeff = par.fAlign >> 0 & 0x03,
163 y_coeff = par.fAlign >> 2 & 0x03;
164
165 SkASSERT(x_coeff < std::size(gAlignCoeffs) &&
166 y_coeff < std::size(gAlignCoeffs));
167
168 const auto tx = -viewBox.x() * scale.x,
169 ty = -viewBox.y() * scale.y,
170 dx = viewPort.width() - viewBox.width() * scale.x,
171 dy = viewPort.height() - viewBox.height() * scale.y;
172
173 return {
174 tx + dx * gAlignCoeffs[x_coeff],
175 ty + dy * gAlignCoeffs[y_coeff]
176 };
177 };
178
179 const auto s = compute_scale(),
180 t = compute_trans(s);
181
182 return SkMatrix::Translate(t.x, t.y) *
183 SkMatrix::Scale(s.x, s.y);
184 }
185