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 <tuple>
9
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkRRect.h"
12 #include "include/core/SkRect.h"
13 #include "modules/svg/include/SkSVGRect.h"
14 #include "modules/svg/include/SkSVGRenderContext.h"
15 #include "modules/svg/src/SkSVGRectPriv.h"
16
ResolveOptionalRadii(const SkTLazy<SkSVGLength> & opt_rx,const SkTLazy<SkSVGLength> & opt_ry,const SkSVGLengthContext & lctx)17 std::tuple<float, float> ResolveOptionalRadii(const SkTLazy<SkSVGLength>& opt_rx,
18 const SkTLazy<SkSVGLength>& opt_ry,
19 const SkSVGLengthContext& lctx) {
20 // https://www.w3.org/TR/SVG2/shapes.html#RectElement
21 //
22 // The used values for rx and ry are determined from the computed values by following these
23 // steps in order:
24 //
25 // 1. If both rx and ry have a computed value of auto (since auto is the initial value for both
26 // properties, this will also occur if neither are specified by the author or if all
27 // author-supplied values are invalid), then the used value of both rx and ry is 0.
28 // (This will result in square corners.)
29 // 2. Otherwise, convert specified values to absolute values as follows:
30 // 1. If rx is set to a length value or a percentage, but ry is auto, calculate an absolute
31 // length equivalent for rx, resolving percentages against the used width of the
32 // rectangle; the absolute value for ry is the same.
33 // 2. If ry is set to a length value or a percentage, but rx is auto, calculate the absolute
34 // length equivalent for ry, resolving percentages against the used height of the
35 // rectangle; the absolute value for rx is the same.
36 // 3. If both rx and ry were set to lengths or percentages, absolute values are generated
37 // individually, resolving rx percentages against the used width, and resolving ry
38 // percentages against the used height.
39 const float rx = opt_rx.isValid()
40 ? lctx.resolve(*opt_rx, SkSVGLengthContext::LengthType::kHorizontal)
41 : 0;
42 const float ry = opt_ry.isValid()
43 ? lctx.resolve(*opt_ry, SkSVGLengthContext::LengthType::kVertical)
44 : 0;
45
46 return std::make_tuple(opt_rx.isValid() ? rx : ry,
47 opt_ry.isValid() ? ry : rx);
48 }
49
SkSVGRect()50 SkSVGRect::SkSVGRect() : INHERITED(SkSVGTag::kRect) {}
51
parseAndSetAttribute(const char * n,const char * v)52 bool SkSVGRect::parseAndSetAttribute(const char* n, const char* v) {
53 return INHERITED::parseAndSetAttribute(n, v) ||
54 this->setX(SkSVGAttributeParser::parse<SkSVGLength>("x", n, v)) ||
55 this->setY(SkSVGAttributeParser::parse<SkSVGLength>("y", n, v)) ||
56 this->setWidth(SkSVGAttributeParser::parse<SkSVGLength>("width", n, v)) ||
57 this->setHeight(SkSVGAttributeParser::parse<SkSVGLength>("height", n, v)) ||
58 this->setRx(SkSVGAttributeParser::parse<SkSVGLength>("rx", n, v)) ||
59 this->setRy(SkSVGAttributeParser::parse<SkSVGLength>("ry", n, v));
60 }
61
resolve(const SkSVGLengthContext & lctx) const62 SkRRect SkSVGRect::resolve(const SkSVGLengthContext& lctx) const {
63 const auto rect = lctx.resolveRect(fX, fY, fWidth, fHeight);
64 const auto [ rx, ry ] = ResolveOptionalRadii(fRx, fRy, lctx);
65
66 // https://www.w3.org/TR/SVG2/shapes.html#RectElement
67 // ...
68 // 3. Finally, apply clamping to generate the used values:
69 // 1. If the absolute rx (after the above steps) is greater than half of the used width,
70 // then the used value of rx is half of the used width.
71 // 2. If the absolute ry (after the above steps) is greater than half of the used height,
72 // then the used value of ry is half of the used height.
73 // 3. Otherwise, the used values of rx and ry are the absolute values computed previously.
74
75 return SkRRect::MakeRectXY(rect,
76 std::min(rx, rect.width() / 2),
77 std::min(ry, rect.height() / 2));
78 }
79
onDraw(SkCanvas * canvas,const SkSVGLengthContext & lctx,const SkPaint & paint,SkPathFillType) const80 void SkSVGRect::onDraw(SkCanvas* canvas, const SkSVGLengthContext& lctx,
81 const SkPaint& paint, SkPathFillType) const {
82 canvas->drawRRect(this->resolve(lctx), paint);
83 }
84
onAsPath(const SkSVGRenderContext & ctx) const85 SkPath SkSVGRect::onAsPath(const SkSVGRenderContext& ctx) const {
86 SkPath path = SkPath::RRect(this->resolve(ctx.lengthContext()));
87
88 this->mapToParent(&path);
89
90 return path;
91 }
92
onObjectBoundingBox(const SkSVGRenderContext & ctx) const93 SkRect SkSVGRect::onObjectBoundingBox(const SkSVGRenderContext& ctx) const {
94 return ctx.lengthContext().resolveRect(fX, fY, fWidth, fHeight);
95 }
96