1 /*
2 * Copyright 2020 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
8 #include "gm/gm.h"
9 #include "include/core/SkCanvas.h"
10 #include "include/core/SkData.h"
11 #include "include/core/SkPicture.h"
12 #include "include/core/SkPictureRecorder.h"
13
14 #include <cmath>
15
16 struct Info {
17 float fNear = 0.05f;
18 float fFar = 4;
19 float fAngle = SK_ScalarPI / 4;
20
21 SkV3 fEye { 0, 0, 1.0f/std::tan(fAngle/2) - 1 };
22 SkV3 fCOA { 0, 0, 0 };
23 SkV3 fUp { 0, 1, 0 };
24 };
25
inv(const SkM44 & m)26 static SkM44 inv(const SkM44& m) {
27 SkM44 inverse(SkM44::kUninitialized_Constructor);
28 if (!m.invert(&inverse)) {
29 inverse.setIdentity();
30 }
31 return inverse;
32 }
33
make_ctm(const Info & info,const SkM44 & model,SkSize size)34 static SkM44 make_ctm(const Info& info, const SkM44& model, SkSize size) {
35 SkM44 camera, perspective, viewport;
36
37 SkScalar w = size.width();
38 SkScalar h = size.height();
39
40 perspective = SkM44::Perspective(info.fNear, info.fFar, info.fAngle);
41 camera = SkM44::LookAt(info.fEye, info.fCOA, info.fUp);
42 viewport.setScale(w*0.5f, h*0.5f, 1);//.postTranslate(r.centerX(), r.centerY(), 0);
43
44 return viewport * perspective * camera * model * inv(viewport);
45 }
46
do_draw(SkCanvas * canvas,SkColor color)47 static void do_draw(SkCanvas* canvas, SkColor color) {
48 SkAutoCanvasRestore acr(canvas, true);
49
50 Info info;
51
52 SkM44 m = SkM44::Rotate({0, 1, 0}, SK_ScalarPI/6);
53
54 canvas->concat(make_ctm(info, m, {300, 300}));
55
56 canvas->translate(150, 150);
57 SkPaint paint;
58 paint.setColor(color);
59 canvas->drawRect({-100, -100, 100, 100}, paint);
60 }
61
62 /*
63 * Test calling drawables w/ translate and matrices
64 */
65 DEF_SIMPLE_GM(sk3d_simple, real_canvas, 300, 300) {
66 do_draw(real_canvas, 0xFFFF0000);
67
68 SkPictureRecorder recorder;
69 SkCanvas* canvas = recorder.beginRecording(300, 300);
70
71 do_draw(canvas, 0x880000FF);
72
73 auto pic = recorder.finishRecordingAsPicture();
74 real_canvas->drawPicture(pic);
75 }
76