1 /*
2 * Copyright 2011 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 "SkView.h"
11 #include "SkCanvas.h"
12 #include "SkCornerPathEffect.h"
13 #include "SkGradientShader.h"
14 #include "SkGraphics.h"
15 #include "SkPath.h"
16 #include "SkRandom.h"
17 #include "SkRegion.h"
18 #include "SkShader.h"
19 #include "SkUtils.h"
20 #include "SkColorPriv.h"
21 #include "SkColorFilter.h"
22 #include "SkTime.h"
23 #include "SkTypeface.h"
24 #include "SkStream.h"
25 #include "SkColorPriv.h"
26
27 static SkRandom gRand;
28
generate_pts(SkPoint pts[],int count,int w,int h)29 static void generate_pts(SkPoint pts[], int count, int w, int h) {
30 for (int i = 0; i < count; i++) {
31 pts[i].set(gRand.nextUScalar1() * 3 * w - SkIntToScalar(w),
32 gRand.nextUScalar1() * 3 * h - SkIntToScalar(h));
33 }
34 }
35
check_zeros(const SkPMColor pixels[],int count,int skip)36 static bool check_zeros(const SkPMColor pixels[], int count, int skip) {
37 for (int i = 0; i < count; i++) {
38 if (*pixels) {
39 return false;
40 }
41 pixels += skip;
42 }
43 return true;
44 }
45
check_bitmap_margin(const SkBitmap & bm,int margin)46 static bool check_bitmap_margin(const SkBitmap& bm, int margin) {
47 size_t rb = bm.rowBytes();
48 for (int i = 0; i < margin; i++) {
49 if (!check_zeros(bm.getAddr32(0, i), bm.width(), 1)) {
50 return false;
51 }
52 int bottom = bm.height() - i - 1;
53 if (!check_zeros(bm.getAddr32(0, bottom), bm.width(), 1)) {
54 return false;
55 }
56 // left column
57 if (!check_zeros(bm.getAddr32(i, 0), bm.height(), SkToInt(rb >> 2))) {
58 return false;
59 }
60 int right = bm.width() - margin + i;
61 if (!check_zeros(bm.getAddr32(right, 0), bm.height(),
62 SkToInt(rb >> 2))) {
63 return false;
64 }
65 }
66 return true;
67 }
68
69 #define WIDTH 620
70 #define HEIGHT 460
71 #define MARGIN 10
72
line_proc(SkCanvas * canvas,const SkPaint & paint,const SkBitmap & bm)73 static void line_proc(SkCanvas* canvas, const SkPaint& paint,
74 const SkBitmap& bm) {
75 const int N = 2;
76 SkPoint pts[N];
77 for (int i = 0; i < 400; i++) {
78 generate_pts(pts, N, WIDTH, HEIGHT);
79
80 canvas->drawLine(pts[0].fX, pts[0].fY, pts[1].fX, pts[1].fY, paint);
81 if (!check_bitmap_margin(bm, MARGIN)) {
82 SkDebugf("---- hairline failure (%g %g) (%g %g)\n",
83 pts[0].fX, pts[0].fY, pts[1].fX, pts[1].fY);
84 break;
85 }
86 }
87 }
88
poly_proc(SkCanvas * canvas,const SkPaint & paint,const SkBitmap & bm)89 static void poly_proc(SkCanvas* canvas, const SkPaint& paint,
90 const SkBitmap& bm) {
91 const int N = 8;
92 SkPoint pts[N];
93 for (int i = 0; i < 50; i++) {
94 generate_pts(pts, N, WIDTH, HEIGHT);
95
96 SkPath path;
97 path.moveTo(pts[0]);
98 for (int j = 1; j < N; j++) {
99 path.lineTo(pts[j]);
100 }
101 canvas->drawPath(path, paint);
102 }
103 }
104
ave(const SkPoint & a,const SkPoint & b)105 static SkPoint ave(const SkPoint& a, const SkPoint& b) {
106 SkPoint c = a + b;
107 c.fX = SkScalarHalf(c.fX);
108 c.fY = SkScalarHalf(c.fY);
109 return c;
110 }
111
quad_proc(SkCanvas * canvas,const SkPaint & paint,const SkBitmap & bm)112 static void quad_proc(SkCanvas* canvas, const SkPaint& paint,
113 const SkBitmap& bm) {
114 const int N = 30;
115 SkPoint pts[N];
116 for (int i = 0; i < 10; i++) {
117 generate_pts(pts, N, WIDTH, HEIGHT);
118
119 SkPath path;
120 path.moveTo(pts[0]);
121 for (int j = 1; j < N - 2; j++) {
122 path.quadTo(pts[j], ave(pts[j], pts[j+1]));
123 }
124 path.quadTo(pts[N - 2], pts[N - 1]);
125
126 canvas->drawPath(path, paint);
127 }
128 }
129
add_cubic(SkPath * path,const SkPoint & mid,const SkPoint & end)130 static void add_cubic(SkPath* path, const SkPoint& mid, const SkPoint& end) {
131 SkPoint start;
132 path->getLastPt(&start);
133 path->cubicTo(ave(start, mid), ave(mid, end), end);
134 }
135
cube_proc(SkCanvas * canvas,const SkPaint & paint,const SkBitmap & bm)136 static void cube_proc(SkCanvas* canvas, const SkPaint& paint,
137 const SkBitmap& bm) {
138 const int N = 30;
139 SkPoint pts[N];
140 for (int i = 0; i < 10; i++) {
141 generate_pts(pts, N, WIDTH, HEIGHT);
142
143 SkPath path;
144 path.moveTo(pts[0]);
145 for (int j = 1; j < N - 2; j++) {
146 add_cubic(&path, pts[j], ave(pts[j], pts[j+1]));
147 }
148 add_cubic(&path, pts[N - 2], pts[N - 1]);
149
150 canvas->drawPath(path, paint);
151 }
152 }
153
154 typedef void (*HairProc)(SkCanvas*, const SkPaint&, const SkBitmap&);
155
156 static const struct {
157 const char* fName;
158 HairProc fProc;
159 } gProcs[] = {
160 { "line", line_proc },
161 { "poly", poly_proc },
162 { "quad", quad_proc },
163 { "cube", cube_proc },
164 };
165
cycle_hairproc_index(int index)166 static int cycle_hairproc_index(int index) {
167 return (index + 1) % SK_ARRAY_COUNT(gProcs);
168 }
169
170 class HairlineView : public SampleView {
171 SkMSec fNow;
172 int fProcIndex;
173 bool fDoAA;
174 public:
HairlineView()175 HairlineView() {
176 fProcIndex = 0;
177 fDoAA = true;
178 fNow = 0;
179 }
180
181 protected:
182 // overrides from SkEventSink
onQuery(SkEvent * evt)183 bool onQuery(SkEvent* evt) override {
184 if (SampleCode::TitleQ(*evt)) {
185 SkString str;
186 str.printf("Hair-%s", gProcs[fProcIndex].fName);
187 SampleCode::TitleR(evt, str.c_str());
188 return true;
189 }
190 return this->INHERITED::onQuery(evt);
191 }
192
show_bitmaps(SkCanvas * canvas,const SkBitmap & b0,const SkBitmap & b1,const SkIRect & inset)193 void show_bitmaps(SkCanvas* canvas, const SkBitmap& b0, const SkBitmap& b1,
194 const SkIRect& inset) {
195 canvas->drawBitmap(b0, 0, 0, nullptr);
196 canvas->drawBitmap(b1, SkIntToScalar(b0.width()), 0, nullptr);
197 }
198
onDrawContent(SkCanvas * canvas)199 void onDrawContent(SkCanvas* canvas) override {
200 gRand.setSeed(fNow);
201
202 SkBitmap bm, bm2;
203 bm.allocN32Pixels(WIDTH + MARGIN*2, HEIGHT + MARGIN*2);
204 // this will erase our margin, which we want to always stay 0
205 bm.eraseColor(SK_ColorTRANSPARENT);
206
207 bm2.installPixels(SkImageInfo::MakeN32Premul(WIDTH, HEIGHT),
208 bm.getAddr32(MARGIN, MARGIN), bm.rowBytes());
209
210 SkCanvas c2(bm2);
211 SkPaint paint;
212 paint.setAntiAlias(fDoAA);
213 paint.setStyle(SkPaint::kStroke_Style);
214
215 bm2.eraseColor(SK_ColorTRANSPARENT);
216 gProcs[fProcIndex].fProc(&c2, paint, bm);
217 canvas->drawBitmap(bm2, SkIntToScalar(10), SkIntToScalar(10), nullptr);
218 }
219
onAnimate(const SkAnimTimer &)220 bool onAnimate(const SkAnimTimer&) override {
221 if (fDoAA) {
222 fProcIndex = cycle_hairproc_index(fProcIndex);
223 // todo: signal that we want to rebuild our TITLE
224 }
225 fDoAA = !fDoAA;
226 return true;
227 }
228
onFindClickHandler(SkScalar x,SkScalar y,unsigned modi)229 SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
230 fDoAA = !fDoAA;
231 this->inval(nullptr);
232 return this->INHERITED::onFindClickHandler(x, y, modi);
233 }
234
235
236 private:
237 typedef SampleView INHERITED;
238 };
239
240 //////////////////////////////////////////////////////////////////////////////
241
MyFactory()242 static SkView* MyFactory() { return new HairlineView; }
243 static SkViewRegister reg(MyFactory);
244