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 #include "src/pathops/SkOpEdgeBuilder.h"
8 #include "src/pathops/SkPathOpsCommon.h"
9
TightBounds(const SkPath & path,SkRect * result)10 bool TightBounds(const SkPath& path, SkRect* result) {
11 SkPath::RawIter iter(path);
12 SkRect moveBounds = { SK_ScalarMax, SK_ScalarMax, SK_ScalarMin, SK_ScalarMin };
13 bool wellBehaved = true;
14 SkPath::Verb verb;
15 do {
16 SkPoint pts[4];
17 verb = iter.next(pts);
18 switch (verb) {
19 case SkPath::kMove_Verb:
20 moveBounds.fLeft = SkTMin(moveBounds.fLeft, pts[0].fX);
21 moveBounds.fTop = SkTMin(moveBounds.fTop, pts[0].fY);
22 moveBounds.fRight = SkTMax(moveBounds.fRight, pts[0].fX);
23 moveBounds.fBottom = SkTMax(moveBounds.fBottom, pts[0].fY);
24 break;
25 case SkPath::kQuad_Verb:
26 case SkPath::kConic_Verb:
27 if (!wellBehaved) {
28 break;
29 }
30 wellBehaved &= between(pts[0].fX, pts[1].fX, pts[2].fX);
31 wellBehaved &= between(pts[0].fY, pts[1].fY, pts[2].fY);
32 break;
33 case SkPath::kCubic_Verb:
34 if (!wellBehaved) {
35 break;
36 }
37 wellBehaved &= between(pts[0].fX, pts[1].fX, pts[3].fX);
38 wellBehaved &= between(pts[0].fY, pts[1].fY, pts[3].fY);
39 wellBehaved &= between(pts[0].fX, pts[2].fX, pts[3].fX);
40 wellBehaved &= between(pts[0].fY, pts[2].fY, pts[3].fY);
41 break;
42 default:
43 break;
44 }
45 } while (verb != SkPath::kDone_Verb);
46 if (wellBehaved) {
47 *result = path.getBounds();
48 return true;
49 }
50 SkSTArenaAlloc<4096> allocator; // FIXME: constant-ize, tune
51 SkOpContour contour;
52 SkOpContourHead* contourList = static_cast<SkOpContourHead*>(&contour);
53 SkOpGlobalState globalState(contourList, &allocator SkDEBUGPARAMS(false)
54 SkDEBUGPARAMS(nullptr));
55 // turn path into list of segments
56 SkOpEdgeBuilder builder(path, contourList, &globalState);
57 if (!builder.finish()) {
58 return false;
59 }
60 if (!SortContourList(&contourList, false, false)) {
61 *result = moveBounds;
62 return true;
63 }
64 SkOpContour* current = contourList;
65 SkPathOpsBounds bounds = current->bounds();
66 while ((current = current->next())) {
67 bounds.add(current->bounds());
68 }
69 *result = bounds;
70 if (!moveBounds.isEmpty()) {
71 result->join(moveBounds);
72 }
73 return true;
74 }
75