1 /*
2 * Copyright 2015 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 "SampleCode.h"
9 #include "SkAnimTimer.h"
10 #include "SkCanvas.h"
11 #include "SkGradientShader.h"
12 #include "SkPatchUtils.h"
13 #include "SkPerlinNoiseShader2/SkPerlinNoiseShader2.h"
14
draw_control_points(SkCanvas * canvas,const SkPoint cubics[12])15 static void draw_control_points(SkCanvas* canvas, const SkPoint cubics[12]) {
16 //draw control points
17 SkPaint paint;
18 SkPoint bottom[SkPatchUtils::kNumPtsCubic];
19 SkPatchUtils::getBottomCubic(cubics, bottom);
20 SkPoint top[SkPatchUtils::kNumPtsCubic];
21 SkPatchUtils::getTopCubic(cubics, top);
22 SkPoint left[SkPatchUtils::kNumPtsCubic];
23 SkPatchUtils::getLeftCubic(cubics, left);
24 SkPoint right[SkPatchUtils::kNumPtsCubic];
25 SkPatchUtils::getRightCubic(cubics, right);
26
27 paint.setColor(SK_ColorBLACK);
28 paint.setStrokeWidth(0.5f);
29 SkPoint corners[4] = { bottom[0], bottom[3], top[0], top[3] };
30 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, bottom, paint);
31 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, bottom + 1, paint);
32 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, top, paint);
33 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, left, paint);
34 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, right, paint);
35
36 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, top + 1, paint);
37 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, left + 1, paint);
38 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, right + 1, paint);
39
40 paint.setStrokeWidth(2);
41
42 paint.setColor(SK_ColorRED);
43 canvas->drawPoints(SkCanvas::kPoints_PointMode, 4, corners, paint);
44
45 paint.setColor(SK_ColorBLUE);
46 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, bottom + 1, paint);
47
48 paint.setColor(SK_ColorCYAN);
49 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, top + 1, paint);
50
51 paint.setColor(SK_ColorYELLOW);
52 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, left + 1, paint);
53
54 paint.setColor(SK_ColorGREEN);
55 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right + 1, paint);
56 }
57
58 // These are actually half the total width and hieghts
59 const SkScalar TexWidth = 100.0f;
60 const SkScalar TexHeight = 100.0f;
61
62 class PerlinPatchView : public SampleView {
63 SkShader* fShader0;
64 SkShader* fShader1;
65 SkShader* fShaderCompose;
66 SkScalar fXFreq;
67 SkScalar fYFreq;
68 SkScalar fSeed;
69 SkPoint fPts[SkPatchUtils::kNumCtrlPts];
70 SkScalar fTexX;
71 SkScalar fTexY;
72 SkScalar fTexScale;
73 SkMatrix fInvMatrix;
74 public:
PerlinPatchView()75 PerlinPatchView() : fXFreq(0.025f), fYFreq(0.025f), fSeed(0.0f),
76 fTexX(100.0), fTexY(50.0), fTexScale(1.0f) {
77 const SkScalar s = 2;
78 // The order of the colors and points is clockwise starting at upper-left corner.
79 //top points
80 fPts[0].set(100 * s, 100 * s);
81 fPts[1].set(150 * s, 50 * s);
82 fPts[2].set(250 * s, 150 * s);
83 fPts[3].set(300 * s, 100 * s);
84 //right points
85 fPts[4].set(275 * s, 150 * s);
86 fPts[5].set(350 * s, 250 * s);
87 //bottom points
88 fPts[6].set(300 * s, 300 * s);
89 fPts[7].set(250 * s, 250 * s);
90 //left points
91 fPts[8].set(150 * s, 350 * s);
92 fPts[9].set(100 * s, 300 * s);
93 fPts[10].set(50 * s, 250 * s);
94 fPts[11].set(150 * s, 150 * s);
95
96 const SkColor colors[SkPatchUtils::kNumCorners] = {
97 0xFF5555FF, 0xFF8888FF, 0xFFCCCCFF
98 };
99 const SkPoint points[2] = { SkPoint::Make(0.0f, 0.0f),
100 SkPoint::Make(100.0f, 100.0f) };
101 fShader0 = SkGradientShader::CreateLinear(points,
102 colors,
103 NULL,
104 3,
105 SkShader::kMirror_TileMode,
106 0,
107 NULL);
108 }
109
~PerlinPatchView()110 virtual ~PerlinPatchView() {
111 SkSafeUnref(fShader0);
112 }
113 protected:
114 // overrides from SkEventSink
onQuery(SkEvent * evt)115 bool onQuery(SkEvent* evt) override {
116 if (SampleCode::TitleQ(*evt)) {
117 SampleCode::TitleR(evt, "PerlinPatch");
118 return true;
119 }
120 return this->INHERITED::onQuery(evt);
121 }
122
onAnimate(const SkAnimTimer & timer)123 bool onAnimate(const SkAnimTimer& timer) override {
124 fSeed += 0.005f;
125 return true;
126 }
127
128
onDrawContent(SkCanvas * canvas)129 void onDrawContent(SkCanvas* canvas) override {
130 if (!canvas->getTotalMatrix().invert(&fInvMatrix)) {
131 return;
132 }
133
134 SkPaint paint;
135
136 SkScalar texWidth = fTexScale * TexWidth;
137 SkScalar texHeight = fTexScale * TexHeight;
138 const SkPoint texCoords[SkPatchUtils::kNumCorners] = {
139 { fTexX - texWidth, fTexY - texHeight},
140 { fTexX + texWidth, fTexY - texHeight},
141 { fTexX + texWidth, fTexY + texHeight},
142 { fTexX - texWidth, fTexY + texHeight}}
143 ;
144
145 SkAutoTUnref<SkXfermode> xfer(SkXfermode::Create(SkXfermode::kSrc_Mode));
146
147 SkScalar scaleFreq = 2.0;
148 fShader1 = SkPerlinNoiseShader2::CreateImprovedNoise(fXFreq/scaleFreq, fYFreq/scaleFreq, 4,
149 fSeed);
150 fShaderCompose = SkShader::CreateComposeShader(fShader0, fShader1, nullptr);
151
152 paint.setShader(fShaderCompose);
153 canvas->drawPatch(fPts, nullptr, texCoords, xfer, paint);
154
155 draw_control_points(canvas, fPts);
156 SkSafeUnref(fShader1);
157 SkSafeUnref(fShaderCompose);
158 }
159
160 class PtClick : public Click {
161 public:
162 int fIndex;
PtClick(SkView * view,int index)163 PtClick(SkView* view, int index) : Click(view), fIndex(index) {}
164 };
165
hittest(const SkPoint & pt,SkScalar x,SkScalar y)166 static bool hittest(const SkPoint& pt, SkScalar x, SkScalar y) {
167 return SkPoint::Length(pt.fX - x, pt.fY - y) < SkIntToScalar(5);
168 }
169
onFindClickHandler(SkScalar x,SkScalar y,unsigned modi)170 SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
171 // holding down shift
172 if (1 == modi) {
173 return new PtClick(this, -1);
174 }
175 // holding down ctrl
176 if (2 == modi) {
177 return new PtClick(this, -2);
178 }
179 SkPoint clickPoint = {x, y};
180 fInvMatrix.mapPoints(&clickPoint, 1);
181 for (size_t i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
182 if (hittest(fPts[i], clickPoint.fX, clickPoint.fY)) {
183 return new PtClick(this, (int)i);
184 }
185 }
186 return this->INHERITED::onFindClickHandler(x, y, modi);
187 }
188
onClick(Click * click)189 bool onClick(Click* click) override {
190 PtClick* ptClick = (PtClick*)click;
191 if (ptClick->fIndex >= 0) {
192 fPts[ptClick->fIndex].set(click->fCurr.fX , click->fCurr.fY );
193 } else if (-1 == ptClick->fIndex) {
194 SkScalar xDiff = click->fPrev.fX - click->fCurr.fX;
195 SkScalar yDiff = click->fPrev.fY - click->fCurr.fY;
196 fTexX += xDiff * fTexScale;
197 fTexY += yDiff * fTexScale;
198 } else if (-2 == ptClick->fIndex) {
199 SkScalar yDiff = click->fCurr.fY - click->fPrev.fY;
200 fTexScale += yDiff / 10.0f;
201 fTexScale = SkTMax(0.1f, SkTMin(20.f, fTexScale));
202 }
203 this->inval(nullptr);
204 return true;
205 }
206
207 private:
208 typedef SampleView INHERITED;
209 };
210
211 DEF_SAMPLE( return new PerlinPatchView(); )
212
213