1 #include "SkMeshUtils.h"
2 #include "SkCanvas.h"
3 #include "SkPaint.h"
4
SkMeshIndices()5 SkMeshIndices::SkMeshIndices() {
6 sk_bzero(this, sizeof(*this));
7 }
8
~SkMeshIndices()9 SkMeshIndices::~SkMeshIndices() {
10 sk_free(fStorage);
11 }
12
init(SkPoint tex[],uint16_t indices[],int texW,int texH,int rows,int cols)13 bool SkMeshIndices::init(SkPoint tex[], uint16_t indices[],
14 int texW, int texH, int rows, int cols) {
15 if (rows < 2 || cols < 2) {
16 sk_free(fStorage);
17 fStorage = NULL;
18 fTex = NULL;
19 fIndices = NULL;
20 fTexCount = fIndexCount = 0;
21 return false;
22 }
23
24 sk_free(fStorage);
25 fStorage = NULL;
26
27 fTexCount = rows * cols;
28 rows -= 1;
29 cols -= 1;
30 fIndexCount = rows * cols * 6;
31
32 if (tex) {
33 fTex = tex;
34 fIndices = indices;
35 } else {
36 fStorage = sk_malloc_throw(fTexCount * sizeof(SkPoint) +
37 fIndexCount * sizeof(uint16_t));
38 fTex = (SkPoint*)fStorage;
39 fIndices = (uint16_t*)(fTex + fTexCount);
40 }
41
42 // compute the indices
43 {
44 uint16_t* idx = fIndices;
45 int index = 0;
46 for (int y = 0; y < cols; y++) {
47 for (int x = 0; x < rows; x++) {
48 *idx++ = index;
49 *idx++ = index + rows + 1;
50 *idx++ = index + 1;
51
52 *idx++ = index + 1;
53 *idx++ = index + rows + 1;
54 *idx++ = index + rows + 2;
55
56 index += 1;
57 }
58 index += 1;
59 }
60 }
61
62 // compute texture coordinates
63 {
64 SkPoint* tex = fTex;
65 const SkScalar dx = SkIntToScalar(texW) / rows;
66 const SkScalar dy = SkIntToScalar(texH) / cols;
67 for (int y = 0; y <= cols; y++) {
68 for (int x = 0; x <= rows; x++) {
69 tex->set(x*dx, y*dy);
70 tex += 1;
71 }
72 }
73 }
74 return true;
75 }
76
77 ///////////////////////////////////////////////////////////////////////////////
78
79 #include "SkShader.h"
80
Draw(SkCanvas * canvas,const SkBitmap & bitmap,int rows,int cols,const SkPoint verts[],const SkColor colors[],const SkPaint & paint)81 void SkMeshUtils::Draw(SkCanvas* canvas, const SkBitmap& bitmap,
82 int rows, int cols, const SkPoint verts[],
83 const SkColor colors[], const SkPaint& paint) {
84 SkMeshIndices idx;
85
86 if (idx.init(bitmap.width(), bitmap.height(), rows, cols)) {
87 SkPaint p(paint);
88 p.setShader(SkShader::CreateBitmapShader(bitmap,
89 SkShader::kClamp_TileMode,
90 SkShader::kClamp_TileMode))->unref();
91 canvas->drawVertices(SkCanvas::kTriangles_VertexMode,
92 rows * cols, verts, idx.tex(), colors, NULL,
93 idx.indices(), idx.indexCount(), p);
94 }
95 }
96
97