xref: /aosp_15_r20/external/skia/docs/examples/Octopus_Generator_Animated.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 // Copyright 2020 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 
5 REG_FIDDLE_ANIMATED(Octopus_Generator_Animated, 256, 256, false, 0, 4) {
6 #include <random>
7 
paintOctopus(float x,float y,int size_base,SkColor color,SkCanvas * canvas)8 void paintOctopus(float x, float y, int size_base, SkColor color, SkCanvas* canvas) {
9     SkPaint paint;
10     paint.setAntiAlias(true);
11     paint.setColor(color);
12     int radius = 3*size_base;
13     canvas->drawCircle(x, y, radius, paint);
14     for (int leg = 0; leg < 8; ++leg) {
15       canvas->drawCircle(x - radius + (2*radius/7.5*leg),
16                          y + radius - pow(abs(4-leg), 2), size_base/2 + 2, paint);
17     }
18     paint.setColor(SkColorSetRGB(std::min(255u, SkColorGetR(color) + 20),
19                                  std::min(255u, SkColorGetG(color) + 20),
20                                  std::min(255u, SkColorGetB(color) + 20)));
21     canvas->drawCircle(x-size_base, y+size_base, size_base/2, paint);
22     canvas->drawCircle(x+size_base, y+size_base, size_base/2, paint);
23 }
24 
draw(SkCanvas * canvas)25 void draw(SkCanvas* canvas) {
26     std::default_random_engine rng;
27     const auto randScalar = [&rng](float min, float max) -> float {
28         return std::uniform_real_distribution<float>(min, max)(rng);
29     };
30     const auto randInt = [&rng](int min, int max) -> int {
31         return std::uniform_int_distribution<int>(min, max)(rng);
32     };
33     const auto randOpaqueColor = [&rng]() -> SkColor {
34         return std::uniform_int_distribution<uint32_t>(0, 0xFFFFFF)(rng) | 0xFF000000;
35     };
36 
37     for (int i = 0; i < 400; ++i) {
38       float x = randScalar(0, 256);
39       float y = randScalar(0, 256);
40       int s = randInt(6, 12);
41       SkColor c = randOpaqueColor();
42       float radius = randScalar(0, 40);
43       float angle = (randScalar(0, 1) + frame) * 6.28319;
44       x += radius * cos(angle);
45       y += radius * sin(angle);
46       paintOctopus(x, y, s, c, canvas);
47     }
48 }
49 }  // END FIDDLE
50