1 /*
2 * Copyright 2014 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 "SkMatrix.h"
9 #include "SkPath.h"
10 #include "SkPathOps.h"
11
add(const SkPath & path,SkPathOp op)12 void SkOpBuilder::add(const SkPath& path, SkPathOp op) {
13 if (0 == fOps.count() && op != kUnion_SkPathOp) {
14 fPathRefs.push_back() = SkPath();
15 *fOps.append() = kUnion_SkPathOp;
16 }
17 fPathRefs.push_back() = path;
18 *fOps.append() = op;
19 }
20
reset()21 void SkOpBuilder::reset() {
22 fPathRefs.reset();
23 fOps.reset();
24 }
25
26 /* OPTIMIZATION: Union doesn't need to be all-or-nothing. A run of three or more convex
27 paths with union ops could be locally resolved and still improve over doing the
28 ops one at a time. */
resolve(SkPath * result)29 bool SkOpBuilder::resolve(SkPath* result) {
30 SkPath original = *result;
31 int count = fOps.count();
32 bool allUnion = true;
33 SkPath::Direction firstDir;
34 for (int index = 0; index < count; ++index) {
35 SkPath* test = &fPathRefs[index];
36 if (kUnion_SkPathOp != fOps[index] || test->isInverseFillType()) {
37 allUnion = false;
38 break;
39 }
40 // If all paths are convex, track direction, reversing as needed.
41 if (test->isConvex()) {
42 SkPath::Direction dir;
43 if (!test->cheapComputeDirection(&dir)) {
44 allUnion = false;
45 break;
46 }
47 if (index == 0) {
48 firstDir = dir;
49 } else if (firstDir != dir) {
50 SkPath temp;
51 temp.reverseAddPath(*test);
52 *test = temp;
53 }
54 continue;
55 }
56 // If the path is not convex but its bounds do not intersect the others, simplify is enough.
57 const SkRect& testBounds = test->getBounds();
58 for (int inner = 0; inner < index; ++inner) {
59 // OPTIMIZE: check to see if the contour bounds do not intersect other contour bounds?
60 if (SkRect::Intersects(fPathRefs[inner].getBounds(), testBounds)) {
61 allUnion = false;
62 break;
63 }
64 }
65 }
66 if (!allUnion) {
67 *result = fPathRefs[0];
68 for (int index = 1; index < count; ++index) {
69 if (!Op(*result, fPathRefs[index], fOps[index], result)) {
70 reset();
71 *result = original;
72 return false;
73 }
74 }
75 reset();
76 return true;
77 }
78 SkPath sum;
79 for (int index = 0; index < count; ++index) {
80 if (!Simplify(fPathRefs[index], &fPathRefs[index])) {
81 reset();
82 *result = original;
83 return false;
84 }
85 sum.addPath(fPathRefs[index]);
86 }
87 reset();
88 sum.setFillType(SkPath::kEvenOdd_FillType);
89 bool success = Simplify(sum, result);
90 if (!success) {
91 *result = original;
92 }
93 return success;
94 }
95