The Tor Browser / file comparison
comparison: gfx/skia/trunk/src/animator/SkParseSVGPath.cpp
gfx/skia/trunk/src/animator/SkParseSVGPath.cpp
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
equal
deleted
inserted
replaced
| -1:000000000000 | 0:688834bc456b |
|---|---|
| 1 | |
| 2 /* | |
| 3 * Copyright 2006 The Android Open Source Project | |
| 4 * | |
| 5 * Use of this source code is governed by a BSD-style license that can be | |
| 6 * found in the LICENSE file. | |
| 7 */ | |
| 8 | |
| 9 | |
| 10 #include <ctype.h> | |
| 11 #include "SkDrawPath.h" | |
| 12 #include "SkParse.h" | |
| 13 #include "SkPoint.h" | |
| 14 #include "SkUtils.h" | |
| 15 #define QUADRATIC_APPROXIMATION 1 | |
| 16 | |
| 17 #if QUADRATIC_APPROXIMATION | |
| 18 //////////////////////////////////////////////////////////////////////////////////// | |
| 19 //functions to approximate a cubic using two quadratics | |
| 20 | |
| 21 // midPt sets the first argument to be the midpoint of the other two | |
| 22 // it is used by quadApprox | |
| 23 static inline void midPt(SkPoint& dest,const SkPoint& a,const SkPoint& b) | |
| 24 { | |
| 25 dest.set(SkScalarAve(a.fX, b.fX),SkScalarAve(a.fY, b.fY)); | |
| 26 } | |
| 27 // quadApprox - makes an approximation, which we hope is faster | |
| 28 static void quadApprox(SkPath &fPath, const SkPoint &p0, const SkPoint &p1, const SkPoint &p2) | |
| 29 { | |
| 30 //divide the cubic up into two cubics, then convert them into quadratics | |
| 31 //define our points | |
| 32 SkPoint c,j,k,l,m,n,o,p,q, mid; | |
| 33 fPath.getLastPt(&c); | |
| 34 midPt(j, p0, c); | |
| 35 midPt(k, p0, p1); | |
| 36 midPt(l, p1, p2); | |
| 37 midPt(o, j, k); | |
| 38 midPt(p, k, l); | |
| 39 midPt(q, o, p); | |
| 40 //compute the first half | |
| 41 m.set(SkScalarHalf(3*j.fX - c.fX), SkScalarHalf(3*j.fY - c.fY)); | |
| 42 n.set(SkScalarHalf(3*o.fX -q.fX), SkScalarHalf(3*o.fY - q.fY)); | |
| 43 midPt(mid,m,n); | |
| 44 fPath.quadTo(mid,q); | |
| 45 c = q; | |
| 46 //compute the second half | |
| 47 m.set(SkScalarHalf(3*p.fX - c.fX), SkScalarHalf(3*p.fY - c.fY)); | |
| 48 n.set(SkScalarHalf(3*l.fX -p2.fX),SkScalarHalf(3*l.fY -p2.fY)); | |
| 49 midPt(mid,m,n); | |
| 50 fPath.quadTo(mid,p2); | |
| 51 } | |
| 52 #endif | |
| 53 | |
| 54 | |
| 55 static inline bool is_between(int c, int min, int max) | |
| 56 { | |
| 57 return (unsigned)(c - min) <= (unsigned)(max - min); | |
| 58 } | |
| 59 | |
| 60 static inline bool is_ws(int c) | |
| 61 { | |
| 62 return is_between(c, 1, 32); | |
| 63 } | |
| 64 | |
| 65 static inline bool is_digit(int c) | |
| 66 { | |
| 67 return is_between(c, '0', '9'); | |
| 68 } | |
| 69 | |
| 70 static inline bool is_sep(int c) | |
| 71 { | |
| 72 return is_ws(c) || c == ','; | |
| 73 } | |
| 74 | |
| 75 static const char* skip_ws(const char str[]) | |
| 76 { | |
| 77 SkASSERT(str); | |
| 78 while (is_ws(*str)) | |
| 79 str++; | |
| 80 return str; | |
| 81 } | |
| 82 | |
| 83 static const char* skip_sep(const char str[]) | |
| 84 { | |
| 85 SkASSERT(str); | |
| 86 while (is_sep(*str)) | |
| 87 str++; | |
| 88 return str; | |
| 89 } | |
| 90 | |
| 91 static const char* find_points(const char str[], SkPoint value[], int count, | |
| 92 bool isRelative, SkPoint* relative) | |
| 93 { | |
| 94 str = SkParse::FindScalars(str, &value[0].fX, count * 2); | |
| 95 if (isRelative) { | |
| 96 for (int index = 0; index < count; index++) { | |
| 97 value[index].fX += relative->fX; | |
| 98 value[index].fY += relative->fY; | |
| 99 } | |
| 100 } | |
| 101 return str; | |
| 102 } | |
| 103 | |
| 104 static const char* find_scalar(const char str[], SkScalar* value, | |
| 105 bool isRelative, SkScalar relative) | |
| 106 { | |
| 107 str = SkParse::FindScalar(str, value); | |
| 108 if (isRelative) | |
| 109 *value += relative; | |
| 110 return str; | |
| 111 } | |
| 112 | |
| 113 void SkDrawPath::parseSVG() { | |
| 114 fPath.reset(); | |
| 115 const char* data = d.c_str(); | |
| 116 SkPoint f = {0, 0}; | |
| 117 SkPoint c = {0, 0}; | |
| 118 SkPoint lastc = {0, 0}; | |
| 119 SkPoint points[3]; | |
| 120 char op = '\0'; | |
| 121 char previousOp = '\0'; | |
| 122 bool relative = false; | |
| 123 do { | |
| 124 data = skip_ws(data); | |
| 125 if (data[0] == '\0') | |
| 126 break; | |
| 127 char ch = data[0]; | |
| 128 if (is_digit(ch) || ch == '-' || ch == '+') { | |
| 129 if (op == '\0') | |
| 130 return; | |
| 131 } | |
| 132 else { | |
| 133 op = ch; | |
| 134 relative = false; | |
| 135 if (islower(op)) { | |
| 136 op = (char) toupper(op); | |
| 137 relative = true; | |
| 138 } | |
| 139 data++; | |
| 140 data = skip_sep(data); | |
| 141 } | |
| 142 switch (op) { | |
| 143 case 'M': | |
| 144 data = find_points(data, points, 1, relative, &c); | |
| 145 fPath.moveTo(points[0]); | |
| 146 op = 'L'; | |
| 147 c = points[0]; | |
| 148 break; | |
| 149 case 'L': | |
| 150 data = find_points(data, points, 1, relative, &c); | |
| 151 fPath.lineTo(points[0]); | |
| 152 c = points[0]; | |
| 153 break; | |
| 154 case 'H': { | |
| 155 SkScalar x; | |
| 156 data = find_scalar(data, &x, relative, c.fX); | |
| 157 fPath.lineTo(x, c.fY); | |
| 158 c.fX = x; | |
| 159 } | |
| 160 break; | |
| 161 case 'V': { | |
| 162 SkScalar y; | |
| 163 data = find_scalar(data, &y, relative, c.fY); | |
| 164 fPath.lineTo(c.fX, y); | |
| 165 c.fY = y; | |
| 166 } | |
| 167 break; | |
| 168 case 'C': | |
| 169 data = find_points(data, points, 3, relative, &c); | |
| 170 goto cubicCommon; | |
| 171 case 'S': | |
| 172 data = find_points(data, &points[1], 2, relative, &c); | |
| 173 points[0] = c; | |
| 174 if (previousOp == 'C' || previousOp == 'S') { | |
| 175 points[0].fX -= lastc.fX - c.fX; | |
| 176 points[0].fY -= lastc.fY - c.fY; | |
| 177 } | |
| 178 cubicCommon: | |
| 179 // if (data[0] == '\0') | |
| 180 // return; | |
| 181 #if QUADRATIC_APPROXIMATION | |
| 182 quadApprox(fPath, points[0], points[1], points[2]); | |
| 183 #else //this way just does a boring, slow old cubic | |
| 184 fPath.cubicTo(points[0], points[1], points[2]); | |
| 185 #endif | |
| 186 //if we are using the quadApprox, lastc is what it would have been if we had used | |
| 187 //cubicTo | |
| 188 lastc = points[1]; | |
| 189 c = points[2]; | |
| 190 break; | |
| 191 case 'Q': // Quadratic Bezier Curve | |
| 192 data = find_points(data, points, 2, relative, &c); | |
| 193 goto quadraticCommon; | |
| 194 case 'T': | |
| 195 data = find_points(data, &points[1], 1, relative, &c); | |
| 196 points[0] = points[1]; | |
| 197 if (previousOp == 'Q' || previousOp == 'T') { | |
| 198 points[0].fX = c.fX * 2 - lastc.fX; | |
| 199 points[0].fY = c.fY * 2 - lastc.fY; | |
| 200 } | |
| 201 quadraticCommon: | |
| 202 fPath.quadTo(points[0], points[1]); | |
| 203 lastc = points[0]; | |
| 204 c = points[1]; | |
| 205 break; | |
| 206 case 'Z': | |
| 207 fPath.close(); | |
| 208 #if 0 // !!! still a bug? | |
| 209 if (fPath.isEmpty() && (f.fX != 0 || f.fY != 0)) { | |
| 210 c.fX -= SkScalar.Epsilon; // !!! enough? | |
| 211 fPath.moveTo(c); | |
| 212 fPath.lineTo(f); | |
| 213 fPath.close(); | |
| 214 } | |
| 215 #endif | |
| 216 c = f; | |
| 217 op = '\0'; | |
| 218 break; | |
| 219 case '~': { | |
| 220 SkPoint args[2]; | |
| 221 data = find_points(data, args, 2, false, NULL); | |
| 222 fPath.moveTo(args[0].fX, args[0].fY); | |
| 223 fPath.lineTo(args[1].fX, args[1].fY); | |
| 224 } | |
| 225 break; | |
| 226 default: | |
| 227 SkASSERT(0); | |
| 228 return; | |
| 229 } | |
| 230 if (previousOp == 0) | |
| 231 f = c; | |
| 232 previousOp = op; | |
| 233 } while (data[0] > 0); | |
| 234 } |
