xref: /aosp_15_r20/external/skia/gm/lighting.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2012 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/SkBitmap.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColor.h"
12 #include "include/core/SkImageFilter.h"
13 #include "include/core/SkPaint.h"
14 #include "include/core/SkPoint3.h"
15 #include "include/core/SkRect.h"
16 #include "include/core/SkRefCnt.h"
17 #include "include/core/SkScalar.h"
18 #include "include/core/SkSize.h"
19 #include "include/core/SkString.h"
20 #include "include/effects/SkImageFilters.h"
21 #include "tools/ToolUtils.h"
22 #include "tools/fonts/FontToolUtils.h"
23 #include "tools/timer/TimeUtils.h"
24 
25 #define WIDTH 660
26 #define HEIGHT 660
27 
28 namespace skiagm {
29 
30 class ImageLightingGM : public GM {
31 public:
ImageLightingGM()32     ImageLightingGM()
33         : fAzimuth(SkIntToScalar(kStartAzimuth)) {
34         this->setBGColor(0xFF000000);
35     }
36 
37 protected:
getName() const38     SkString getName() const override { return SkString("lighting"); }
39 
getISize()40     SkISize getISize() override { return SkISize::Make(WIDTH, HEIGHT); }
41 
drawClippedBitmap(SkCanvas * canvas,const SkPaint & paint,int x,int y)42     void drawClippedBitmap(SkCanvas* canvas, const SkPaint& paint, int x, int y) {
43         canvas->save();
44         canvas->translate(SkIntToScalar(x), SkIntToScalar(y));
45         canvas->clipIRect(fBitmap.bounds());
46         canvas->drawImage(fBitmap.asImage(), 0, 0, SkSamplingOptions(), &paint);
47         canvas->restore();
48     }
49 
onOnceBeforeDraw()50     void onOnceBeforeDraw() override {
51         fBitmap = ToolUtils::CreateStringBitmap(100, 100, 0xFFFFFFFF, 20, 70, 96, "e");
52     }
53 
onDraw(SkCanvas * canvas)54     void onDraw(SkCanvas* canvas) override {
55         canvas->clear(0xFF101010);
56         SkPaint checkPaint;
57         checkPaint.setColor(0xFF202020);
58         for (int y = 0; y < HEIGHT; y += 16) {
59           for (int x = 0; x < WIDTH; x += 16) {
60             canvas->save();
61             canvas->translate(SkIntToScalar(x), SkIntToScalar(y));
62             canvas->drawRect(SkRect::MakeXYWH(8, 0, 8, 8), checkPaint);
63             canvas->drawRect(SkRect::MakeXYWH(0, 8, 8, 8), checkPaint);
64             canvas->restore();
65           }
66         }
67         SkScalar sinAzimuth = SkScalarSin(SkDegreesToRadians(fAzimuth)),
68                  cosAzimuth = SkScalarCos(SkDegreesToRadians(fAzimuth));
69 
70         SkPoint3 spotTarget = SkPoint3::Make(SkIntToScalar(40), SkIntToScalar(40), 0);
71         SkPoint3 spotLocation = SkPoint3::Make(spotTarget.fX + 70.7214f * cosAzimuth,
72                                                spotTarget.fY + 70.7214f * sinAzimuth,
73                                                spotTarget.fZ + SkIntToScalar(20));
74         SkScalar spotExponent1 = SK_Scalar1;
75         SkScalar spotExponent10 = SkIntToScalar(10);
76         SkScalar cutoffAngleSmall = SkIntToScalar(15);
77         SkScalar cutoffAngleNone = SkIntToScalar(180);
78 
79         SkPoint3 pointLocation = SkPoint3::Make(spotTarget.fX + 50 * cosAzimuth,
80                                                 spotTarget.fY + 50 * sinAzimuth,
81                                                 SkIntToScalar(10));
82         SkScalar elevationRad = SkDegreesToRadians(SkIntToScalar(5));
83 
84         SkPoint3 distantDirection = SkPoint3::Make(cosAzimuth * SkScalarCos(elevationRad),
85                                                    sinAzimuth * SkScalarCos(elevationRad),
86                                                    SkScalarSin(elevationRad));
87         SkScalar kd = SkIntToScalar(2);
88         SkScalar ks = SkIntToScalar(1);
89         SkScalar shininess = SkIntToScalar(8);
90         SkScalar surfaceScale = SkIntToScalar(1);
91         SkScalar surfaceScaleSmall = 0.1f;
92         SkColor greenYellow = SkColorSetARGB(255, 173, 255, 47);
93         SkPaint paint;
94 
95         SkIRect cropRect = SkIRect::MakeXYWH(20, 10, 60, 65);
96         SkIRect fullSizeCropRect = SkIRect::MakeXYWH(0, 0, 100, 100);
97         sk_sp<SkImageFilter> noopCropped(SkImageFilters::Offset(0, 0, nullptr, &cropRect));
98 
99         int y = 0;
100         for (int i = 0; i < 3; i++) {
101             const SkIRect* cr = (i == 1) ? &cropRect : (i == 2) ? &fullSizeCropRect : nullptr;
102             sk_sp<SkImageFilter> input = (i == 2) ? noopCropped : nullptr;
103             // Basic point, distant and spot lights with diffuse lighting
104             paint.setImageFilter(SkImageFilters::PointLitDiffuse(
105                     pointLocation, SK_ColorWHITE, surfaceScale, kd, input, cr));
106             drawClippedBitmap(canvas, paint, 0, y);
107 
108             paint.setImageFilter(SkImageFilters::DistantLitDiffuse(
109                     distantDirection, SK_ColorWHITE, surfaceScale, kd, input, cr));
110             drawClippedBitmap(canvas, paint, 110, y);
111 
112             paint.setImageFilter(SkImageFilters::SpotLitDiffuse(
113                     spotLocation, spotTarget, spotExponent1, cutoffAngleSmall, SK_ColorWHITE,
114                     surfaceScale, kd, input, cr));
115             drawClippedBitmap(canvas, paint, 220, y);
116 
117             // Spot light with no angle cutoff
118             paint.setImageFilter(SkImageFilters::SpotLitDiffuse(
119                     spotLocation, spotTarget, spotExponent10, cutoffAngleNone, SK_ColorWHITE,
120                     surfaceScale, kd,  input, cr));
121             drawClippedBitmap(canvas, paint, 330, y);
122 
123             // Spot light with falloff exponent
124             paint.setImageFilter(SkImageFilters::SpotLitDiffuse(
125                     spotLocation, spotTarget, spotExponent1, cutoffAngleNone, SK_ColorWHITE,
126                     surfaceScaleSmall, kd, input, cr));
127             drawClippedBitmap(canvas, paint, 440, y);
128 
129             // Large constant to show oversaturation
130             paint.setImageFilter(SkImageFilters::DistantLitDiffuse(
131                     distantDirection, greenYellow, surfaceScale, 4.f * kd, input, cr));
132             drawClippedBitmap(canvas, paint, 550, y);
133 
134             y += 110;
135 
136             // Basic point, distant and spot lights with specular lighting
137             paint.setImageFilter(SkImageFilters::PointLitSpecular(
138                     pointLocation, SK_ColorWHITE, surfaceScale, ks, shininess, input, cr));
139             drawClippedBitmap(canvas, paint, 0, y);
140 
141             paint.setImageFilter(SkImageFilters::DistantLitSpecular(
142                     distantDirection, SK_ColorWHITE, surfaceScale, ks, shininess, input, cr));
143             drawClippedBitmap(canvas, paint, 110, y);
144 
145             paint.setImageFilter(SkImageFilters::SpotLitSpecular(
146                     spotLocation, spotTarget, spotExponent1, cutoffAngleSmall, SK_ColorWHITE,
147                     surfaceScale, ks, shininess, input, cr));
148             drawClippedBitmap(canvas, paint, 220, y);
149 
150             // Spot light with no angle cutoff
151             paint.setImageFilter(SkImageFilters::SpotLitSpecular(
152                     spotLocation, spotTarget, spotExponent10, cutoffAngleNone, SK_ColorWHITE,
153                     surfaceScale, ks,  shininess, input, cr));
154             drawClippedBitmap(canvas, paint, 330, y);
155 
156             // Spot light with falloff exponent
157             paint.setImageFilter(SkImageFilters::SpotLitSpecular(
158                     spotLocation, spotTarget, spotExponent1, cutoffAngleNone, SK_ColorWHITE,
159                     surfaceScaleSmall, ks, shininess, input, cr));
160             drawClippedBitmap(canvas, paint, 440, y);
161 
162             // Large constant to show oversaturation
163             paint.setImageFilter(SkImageFilters::DistantLitSpecular(
164                     distantDirection, greenYellow, surfaceScale, 4.f * ks, shininess, input, cr));
165             drawClippedBitmap(canvas, paint, 550, y);
166 
167             y += 110;
168         }
169     }
170 
onAnimate(double nanos)171     bool onAnimate(double nanos) override {
172         constexpr SkScalar kDesiredDurationSecs = 15.0f;
173 
174         fAzimuth = kStartAzimuth + TimeUtils::Scaled(1e-9 * nanos, 360.0f/kDesiredDurationSecs, 360.0f);
175         return true;
176     }
177 
178 private:
179     inline static constexpr int kStartAzimuth = 225;
180 
181     SkBitmap fBitmap;
182     SkScalar fAzimuth;
183 
184     using INHERITED = GM;
185 };
186 
187 //////////////////////////////////////////////////////////////////////////////
188 
189 DEF_GM(return new ImageLightingGM;)
190 }  // namespace skiagm
191