1 // Copyright 2019 Google LLC.
2 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3 #include "tools/fiddle/examples.h"
4 // HASH=d56f93e4bc763c7ba4914321ed07a8b5
5 REG_FIDDLE(Matrix_mapHomogeneousPoints, 256, 256, false, 0) {
draw(SkCanvas * canvas)6 void draw(SkCanvas* canvas) {
7 SkPoint3 src[] = {{3, 3, 1}, {8, 2, 2}, {5, 0, 4}, {0, 1, 3},
8 {3, 7, 1}, {8, 6, 2}, {5, 4, 4}, {0, 5, 3}};
9 int lines[] = { 0, 1, 1, 2, 2, 3, 3, 0, 4, 5, 5, 6, 6, 7, 7, 4, 0, 4, 1, 5, 2, 6, 3, 7 };
10 constexpr int count = SK_ARRAY_COUNT(src);
11 auto debugster = [=](SkPoint3 src[]) -> void {
12 for (size_t i = 0; i < SK_ARRAY_COUNT(lines); i += 2) {
13 const SkPoint3& s = src[lines[i]];
14 const SkPoint3& e = src[lines[i + 1]];
15 SkPaint paint;
16 paint.setARGB(77, 23, 99, 154);
17 canvas->drawLine(s.fX / s.fZ, s.fY / s.fZ, e.fX / e.fZ, e.fY / e.fZ, paint);
18 }
19 };
20 canvas->save();
21 canvas->translate(5, 5);
22 canvas->scale(15, 15);
23 debugster(src);
24 canvas->restore();
25 canvas->translate(128, 128);
26 SkMatrix matrix;
27 matrix.setAll(15, 0, 0, 0, 15, 0, -0.08f, 0.04f, 1);
28 matrix.mapHomogeneousPoints(src, src, count);
29 debugster(src);
30 }
31 } // END FIDDLE
32