1 /*
2 * Copyright 2012 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 "SkStrokeRec.h"
9 #include "SkPaintDefaults.h"
10
11 // must be < 0, since ==0 means hairline, and >0 means normal stroke
12 #define kStrokeRec_FillStyleWidth (-SK_Scalar1)
13
SkStrokeRec(InitStyle s)14 SkStrokeRec::SkStrokeRec(InitStyle s) {
15 fResScale = 1;
16 fWidth = (kFill_InitStyle == s) ? kStrokeRec_FillStyleWidth : 0;
17 fMiterLimit = SkPaintDefaults_MiterLimit;
18 fCap = SkPaint::kDefault_Cap;
19 fJoin = SkPaint::kDefault_Join;
20 fStrokeAndFill = false;
21 }
22
SkStrokeRec(const SkPaint & paint,SkScalar resScale)23 SkStrokeRec::SkStrokeRec(const SkPaint& paint, SkScalar resScale) {
24 this->init(paint, paint.getStyle(), resScale);
25 }
26
SkStrokeRec(const SkPaint & paint,SkPaint::Style styleOverride,SkScalar resScale)27 SkStrokeRec::SkStrokeRec(const SkPaint& paint, SkPaint::Style styleOverride, SkScalar resScale) {
28 this->init(paint, styleOverride, resScale);
29 }
30
init(const SkPaint & paint,SkPaint::Style style,SkScalar resScale)31 void SkStrokeRec::init(const SkPaint& paint, SkPaint::Style style, SkScalar resScale) {
32 fResScale = resScale;
33
34 switch (style) {
35 case SkPaint::kFill_Style:
36 fWidth = kStrokeRec_FillStyleWidth;
37 fStrokeAndFill = false;
38 break;
39 case SkPaint::kStroke_Style:
40 fWidth = paint.getStrokeWidth();
41 fStrokeAndFill = false;
42 break;
43 case SkPaint::kStrokeAndFill_Style:
44 if (0 == paint.getStrokeWidth()) {
45 // hairline+fill == fill
46 fWidth = kStrokeRec_FillStyleWidth;
47 fStrokeAndFill = false;
48 } else {
49 fWidth = paint.getStrokeWidth();
50 fStrokeAndFill = true;
51 }
52 break;
53 default:
54 SkDEBUGFAIL("unknown paint style");
55 // fall back on just fill
56 fWidth = kStrokeRec_FillStyleWidth;
57 fStrokeAndFill = false;
58 break;
59 }
60
61 // copy these from the paint, regardless of our "style"
62 fMiterLimit = paint.getStrokeMiter();
63 fCap = paint.getStrokeCap();
64 fJoin = paint.getStrokeJoin();
65 }
66
getStyle() const67 SkStrokeRec::Style SkStrokeRec::getStyle() const {
68 if (fWidth < 0) {
69 return kFill_Style;
70 } else if (0 == fWidth) {
71 return kHairline_Style;
72 } else {
73 return fStrokeAndFill ? kStrokeAndFill_Style : kStroke_Style;
74 }
75 }
76
setFillStyle()77 void SkStrokeRec::setFillStyle() {
78 fWidth = kStrokeRec_FillStyleWidth;
79 fStrokeAndFill = false;
80 }
81
setHairlineStyle()82 void SkStrokeRec::setHairlineStyle() {
83 fWidth = 0;
84 fStrokeAndFill = false;
85 }
86
setStrokeStyle(SkScalar width,bool strokeAndFill)87 void SkStrokeRec::setStrokeStyle(SkScalar width, bool strokeAndFill) {
88 if (strokeAndFill && (0 == width)) {
89 // hairline+fill == fill
90 this->setFillStyle();
91 } else {
92 fWidth = width;
93 fStrokeAndFill = strokeAndFill;
94 }
95 }
96
97 #include "SkStroke.h"
98
99 #ifdef SK_DEBUG
100 // enables tweaking these values at runtime from Viewer
101 bool gDebugStrokerErrorSet = false;
102 SkScalar gDebugStrokerError;
103 #endif
104
applyToPath(SkPath * dst,const SkPath & src) const105 bool SkStrokeRec::applyToPath(SkPath* dst, const SkPath& src) const {
106 if (fWidth <= 0) { // hairline or fill
107 return false;
108 }
109
110 SkStroke stroker;
111 stroker.setCap((SkPaint::Cap)fCap);
112 stroker.setJoin((SkPaint::Join)fJoin);
113 stroker.setMiterLimit(fMiterLimit);
114 stroker.setWidth(fWidth);
115 stroker.setDoFill(fStrokeAndFill);
116 #ifdef SK_DEBUG
117 stroker.setResScale(gDebugStrokerErrorSet ? gDebugStrokerError : fResScale);
118 #else
119 stroker.setResScale(fResScale);
120 #endif
121 stroker.strokePath(src, dst);
122 return true;
123 }
124
applyToPaint(SkPaint * paint) const125 void SkStrokeRec::applyToPaint(SkPaint* paint) const {
126 if (fWidth < 0) { // fill
127 paint->setStyle(SkPaint::kFill_Style);
128 return;
129 }
130
131 paint->setStyle(fStrokeAndFill ? SkPaint::kStrokeAndFill_Style : SkPaint::kStroke_Style);
132 paint->setStrokeWidth(fWidth);
133 paint->setStrokeMiter(fMiterLimit);
134 paint->setStrokeCap((SkPaint::Cap)fCap);
135 paint->setStrokeJoin((SkPaint::Join)fJoin);
136 }
137
getInflationRadius() const138 SkScalar SkStrokeRec::getInflationRadius() const {
139 return GetInflationRadius((SkPaint::Join)fJoin, fMiterLimit, (SkPaint::Cap)fCap, fWidth);
140 }
141
GetInflationRadius(const SkPaint & paint,SkPaint::Style style)142 SkScalar SkStrokeRec::GetInflationRadius(const SkPaint& paint, SkPaint::Style style) {
143 SkScalar width = SkPaint::kFill_Style == style ? -SK_Scalar1 : paint.getStrokeWidth();
144 return GetInflationRadius(paint.getStrokeJoin(), paint.getStrokeMiter(), paint.getStrokeCap(),
145 width);
146
147 }
148
GetInflationRadius(SkPaint::Join join,SkScalar miterLimit,SkPaint::Cap cap,SkScalar strokeWidth)149 SkScalar SkStrokeRec::GetInflationRadius(SkPaint::Join join, SkScalar miterLimit, SkPaint::Cap cap,
150 SkScalar strokeWidth) {
151 if (strokeWidth < 0) { // fill
152 return 0;
153 } else if (0 == strokeWidth) {
154 // FIXME: We need a "matrixScale" parameter here in order to properly handle hairlines.
155 // Their with is determined in device space, unlike other strokes.
156 // http://skbug.com/8157
157 return SK_Scalar1;
158 }
159
160 // since we're stroked, outset the rect by the radius (and join type, caps)
161 SkScalar multiplier = SK_Scalar1;
162 if (SkPaint::kMiter_Join == join) {
163 multiplier = SkTMax(multiplier, miterLimit);
164 }
165 if (SkPaint::kSquare_Cap == cap) {
166 multiplier = SkTMax(multiplier, SK_ScalarSqrt2);
167 }
168 return strokeWidth/2 * multiplier;
169 }
170
171