1
2 /*
3 * Copyright 2011 Google Inc.
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 #include "SkBoundaryPatch.h"
9
SK_DEFINE_INST_COUNT(SkBoundary)10 SK_DEFINE_INST_COUNT(SkBoundary)
11
12 SkBoundaryPatch::SkBoundaryPatch() : fBoundary(NULL) {}
13
~SkBoundaryPatch()14 SkBoundaryPatch::~SkBoundaryPatch() {
15 SkSafeUnref(fBoundary);
16 }
17
setBoundary(SkBoundary * b)18 SkBoundary* SkBoundaryPatch::setBoundary(SkBoundary* b) {
19 SkRefCnt_SafeAssign(fBoundary, b);
20 return b;
21 }
22
SkMakePoint(SkScalar x,SkScalar y)23 static SkPoint SkMakePoint(SkScalar x, SkScalar y) {
24 SkPoint pt;
25 pt.set(x, y);
26 return pt;
27 }
28
SkPointInterp(const SkPoint & a,const SkPoint & b,SkScalar t)29 static SkPoint SkPointInterp(const SkPoint& a, const SkPoint& b, SkScalar t) {
30 return SkMakePoint(SkScalarInterp(a.fX, b.fX, t),
31 SkScalarInterp(a.fY, b.fY, t));
32 }
33
eval(SkScalar unitU,SkScalar unitV)34 SkPoint SkBoundaryPatch::eval(SkScalar unitU, SkScalar unitV) {
35 SkBoundary* b = fBoundary;
36 SkPoint u = SkPointInterp(b->eval(SkBoundary::kLeft, SK_Scalar1 - unitV),
37 b->eval(SkBoundary::kRight, unitV),
38 unitU);
39 SkPoint v = SkPointInterp(b->eval(SkBoundary::kTop, unitU),
40 b->eval(SkBoundary::kBottom, SK_Scalar1 - unitU),
41 unitV);
42 return SkMakePoint(SkScalarAve(u.fX, v.fX),
43 SkScalarAve(u.fY, v.fY));
44 }
45
evalPatch(SkPoint verts[],int rows,int cols)46 bool SkBoundaryPatch::evalPatch(SkPoint verts[], int rows, int cols) {
47 if (rows < 2 || cols < 2) {
48 return false;
49 }
50
51 const SkScalar invR = SkScalarInvert(SkIntToScalar(rows - 1));
52 const SkScalar invC = SkScalarInvert(SkIntToScalar(cols - 1));
53
54 for (int y = 0; y < cols; y++) {
55 SkScalar yy = y * invC;
56 for (int x = 0; x < rows; x++) {
57 *verts++ = this->eval(x * invR, yy);
58 }
59 }
60 return true;
61 }
62
63 ////////////////////////////////////////////////////////////////////////
64
65 #include "SkGeometry.h"
66
eval(Edge e,SkScalar t)67 SkPoint SkLineBoundary::eval(Edge e, SkScalar t) {
68 SkASSERT((unsigned)e < 4);
69 return SkPointInterp(fPts[e], fPts[(e + 1) & 3], t);
70 }
71
eval(Edge e,SkScalar t)72 SkPoint SkCubicBoundary::eval(Edge e, SkScalar t) {
73 SkASSERT((unsigned)e < 4);
74
75 // ensure our 4th cubic wraps to the start of the first
76 fPts[12] = fPts[0];
77
78 SkPoint loc;
79 SkEvalCubicAt(&fPts[e * 3], t, &loc, NULL, NULL);
80 return loc;
81 }
82