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 "Sample.h"
9 #include "SkBitmap.h"
10 #include "SkCanvas.h"
11 #include "SkFont.h"
12 #include "SkFontMetrics.h"
13 #include "SkGradientShader.h"
14 #include "SkPath.h"
15 #include "SkRegion.h"
16 #include "SkShader.h"
17 #include "SkUTF.h"
18
19 #include <math.h>
20
test_strokerect(SkCanvas * canvas)21 static void test_strokerect(SkCanvas* canvas) {
22 int width = 100;
23 int height = 100;
24
25 SkBitmap bitmap;
26 bitmap.allocPixels(SkImageInfo::MakeA8(width*2, height*2));
27 bitmap.eraseColor(SK_ColorTRANSPARENT);
28
29 SkScalar dx = 20;
30 SkScalar dy = 20;
31
32 SkPath path;
33 path.addRect(0.0f, 0.0f,
34 SkIntToScalar(width), SkIntToScalar(height),
35 SkPath::kCW_Direction);
36 SkRect r = SkRect::MakeWH(SkIntToScalar(width), SkIntToScalar(height));
37
38 SkCanvas c(bitmap);
39 c.translate(dx, dy);
40
41 SkPaint paint;
42 paint.setStyle(SkPaint::kStroke_Style);
43 paint.setStrokeWidth(1);
44
45 // use the rect
46 c.clear(SK_ColorTRANSPARENT);
47 c.drawRect(r, paint);
48 canvas->drawBitmap(bitmap, 0, 0, nullptr);
49
50 // use the path
51 c.clear(SK_ColorTRANSPARENT);
52 c.drawPath(path, paint);
53 canvas->drawBitmap(bitmap, SkIntToScalar(2*width), 0, nullptr);
54 }
55
drawFadingText(SkCanvas * canvas,const char * text,size_t len,SkScalar x,SkScalar y,const SkFont & font,const SkPaint & paint)56 static void drawFadingText(SkCanvas* canvas,
57 const char* text, size_t len, SkScalar x, SkScalar y,
58 const SkFont& font, const SkPaint& paint) {
59 // Need a bounds for the text
60 SkRect bounds;
61 SkFontMetrics fm;
62
63 font.getMetrics(&fm);
64 bounds.set(x, y + fm.fTop, x + font.measureText(text, len, kUTF8_SkTextEncoding), y + fm.fBottom);
65
66 // may need to outset bounds a little, to account for hinting and/or
67 // antialiasing
68 bounds.inset(-SkIntToScalar(2), -SkIntToScalar(2));
69
70 canvas->saveLayer(&bounds, nullptr);
71 canvas->drawSimpleText(text, len, kUTF8_SkTextEncoding, x, y, font, paint);
72
73 const SkPoint pts[] = {
74 { bounds.fLeft, y },
75 { bounds.fRight, y }
76 };
77 const SkColor colors[] = { SK_ColorBLACK, SK_ColorBLACK, 0 };
78
79 // pos[1] value is where we start to fade, relative to the width
80 // of our pts[] array.
81 const SkScalar pos[] = { 0, 0.9f, SK_Scalar1 };
82
83 SkPaint p;
84 p.setShader(SkGradientShader::MakeLinear(pts, colors, pos, 3, SkShader::kClamp_TileMode));
85 p.setBlendMode(SkBlendMode::kDstIn);
86 canvas->drawRect(bounds, p);
87
88 canvas->restore();
89 }
90
test_text(SkCanvas * canvas)91 static void test_text(SkCanvas* canvas) {
92 SkPaint paint;
93 paint.setAntiAlias(true);
94
95 SkFont font;
96 font.setSize(20);
97
98 const char* str = "Hamburgefons";
99 size_t len = strlen(str);
100 SkScalar x = 20;
101 SkScalar y = 20;
102
103 canvas->drawSimpleText(str, len, kUTF8_SkTextEncoding, x, y, font, paint);
104
105 y += 20;
106
107 const SkPoint pts[] = { { x, y }, { x + font.measureText(str, len, kUTF8_SkTextEncoding), y } };
108 const SkColor colors[] = { SK_ColorBLACK, SK_ColorBLACK, 0 };
109 const SkScalar pos[] = { 0, 0.9f, 1 };
110 paint.setShader(SkGradientShader::MakeLinear(pts, colors, pos,
111 SK_ARRAY_COUNT(colors),
112 SkShader::kClamp_TileMode));
113 canvas->drawSimpleText(str, len, kUTF8_SkTextEncoding, x, y, font, paint);
114
115 y += 20;
116 paint.setShader(nullptr);
117 drawFadingText(canvas, str, len, x, y, font, paint);
118 }
119
scale_rect(SkIRect * dst,const SkIRect & src,float scale)120 static void scale_rect(SkIRect* dst, const SkIRect& src, float scale) {
121 dst->fLeft = (int)::roundf(src.fLeft * scale);
122 dst->fTop = (int)::roundf(src.fTop * scale);
123 dst->fRight = (int)::roundf(src.fRight * scale);
124 dst->fBottom = (int)::roundf(src.fBottom * scale);
125 }
126
scale_rgn(SkRegion * dst,const SkRegion & src,float scale)127 static void scale_rgn(SkRegion* dst, const SkRegion& src, float scale) {
128 SkRegion tmp;
129 SkRegion::Iterator iter(src);
130
131 for (; !iter.done(); iter.next()) {
132 SkIRect r;
133 scale_rect(&r, iter.rect(), scale);
134 tmp.op(r, SkRegion::kUnion_Op);
135 }
136 dst->swap(tmp);
137 }
138
paint_rgn(SkCanvas * canvas,const SkRegion & rgn,const SkPaint & paint)139 static void paint_rgn(SkCanvas* canvas, const SkRegion& rgn,
140 const SkPaint& paint) {
141 SkRegion scaled;
142 scale_rgn(&scaled, rgn, 0.5f);
143
144 SkRegion::Iterator iter(rgn);
145
146 for (; !iter.done(); iter.next())
147 {
148 SkRect r;
149 r.set(iter.rect());
150 canvas->drawRect(r, paint);
151 }
152 }
153
154 class RegionView : public Sample {
155 public:
RegionView()156 RegionView() {
157 fBase.set(100, 100, 150, 150);
158 fRect = fBase;
159 fRect.inset(5, 5);
160 fRect.offset(25, 25);
161 this->setBGColor(0xFFDDDDDD);
162 }
163
build_base_rgn(SkRegion * rgn)164 void build_base_rgn(SkRegion* rgn) {
165 rgn->setRect(fBase);
166 SkIRect r = fBase;
167 r.offset(75, 20);
168 rgn->op(r, SkRegion::kUnion_Op);
169 }
170
build_rgn(SkRegion * rgn,SkRegion::Op op)171 void build_rgn(SkRegion* rgn, SkRegion::Op op) {
172 build_base_rgn(rgn);
173 rgn->op(fRect, op);
174 }
175
176
177 protected:
onQuery(Sample::Event * evt)178 bool onQuery(Sample::Event* evt) override {
179 if (Sample::TitleQ(*evt)) {
180 Sample::TitleR(evt, "Regions");
181 return true;
182 }
183 return this->INHERITED::onQuery(evt);
184 }
185
drawstr(SkCanvas * canvas,const char text[],const SkPoint & loc,bool hilite)186 static void drawstr(SkCanvas* canvas, const char text[], const SkPoint& loc,
187 bool hilite) {
188 SkPaint paint;
189 paint.setColor(hilite ? SK_ColorRED : 0x40FF0000);
190 SkFont font;
191 font.setSize(SkIntToScalar(20));
192 canvas->drawSimpleText(text, strlen(text), kUTF8_SkTextEncoding, loc.fX, loc.fY, font, paint);
193 }
194
drawPredicates(SkCanvas * canvas,const SkPoint pts[])195 void drawPredicates(SkCanvas* canvas, const SkPoint pts[]) {
196 SkRegion rgn;
197 build_base_rgn(&rgn);
198
199 drawstr(canvas, "Intersects", pts[0], rgn.intersects(fRect));
200 drawstr(canvas, "Contains", pts[1], rgn.contains(fRect));
201 }
202
drawOrig(SkCanvas * canvas,bool bg)203 void drawOrig(SkCanvas* canvas, bool bg) {
204 SkRect r;
205 SkPaint paint;
206
207 paint.setStyle(SkPaint::kStroke_Style);
208 if (bg)
209 paint.setColor(0xFFBBBBBB);
210
211 SkRegion rgn;
212 build_base_rgn(&rgn);
213 paint_rgn(canvas, rgn, paint);
214
215 r.set(fRect);
216 canvas->drawRect(r, paint);
217 }
218
drawRgnOped(SkCanvas * canvas,SkRegion::Op op,SkColor color)219 void drawRgnOped(SkCanvas* canvas, SkRegion::Op op, SkColor color) {
220 SkRegion rgn;
221
222 this->build_rgn(&rgn, op);
223
224 {
225 SkRegion tmp, tmp2(rgn);
226
227 tmp = tmp2;
228 tmp.translate(5, -3);
229
230 {
231 char buffer[1000];
232 SkDEBUGCODE(size_t size = ) tmp.writeToMemory(nullptr);
233 SkASSERT(size <= sizeof(buffer));
234 SkDEBUGCODE(size_t size2 = ) tmp.writeToMemory(buffer);
235 SkASSERT(size == size2);
236
237 SkRegion tmp3;
238 SkDEBUGCODE(size2 = ) tmp3.readFromMemory(buffer, 1000);
239 SkASSERT(size == size2);
240
241 SkASSERT(tmp3 == tmp);
242 }
243
244 rgn.translate(20, 30, &tmp);
245 SkASSERT(rgn.isEmpty() || tmp != rgn);
246 tmp.translate(-20, -30);
247 SkASSERT(tmp == rgn);
248 }
249
250 this->drawOrig(canvas, true);
251
252 SkPaint paint;
253 paint.setColor((color & ~(0xFF << 24)) | (0x44 << 24));
254 paint_rgn(canvas, rgn, paint);
255
256 paint.setStyle(SkPaint::kStroke_Style);
257 paint.setColor(color);
258 paint_rgn(canvas, rgn, paint);
259 }
260
drawPathOped(SkCanvas * canvas,SkRegion::Op op,SkColor color)261 void drawPathOped(SkCanvas* canvas, SkRegion::Op op, SkColor color) {
262 SkRegion rgn;
263 SkPath path;
264
265 this->build_rgn(&rgn, op);
266 rgn.getBoundaryPath(&path);
267
268 this->drawOrig(canvas, true);
269
270 SkPaint paint;
271
272 paint.setStyle(SkPaint::kFill_Style);
273 paint.setColor((color & ~(0xFF << 24)) | (0x44 << 24));
274 canvas->drawPath(path, paint);
275 paint.setColor(color);
276 paint.setStyle(SkPaint::kStroke_Style);
277 canvas->drawPath(path, paint);
278 }
279
onDrawContent(SkCanvas * canvas)280 void onDrawContent(SkCanvas* canvas) override {
281 if (false) { // avoid bit rot, suppress warning
282 test_strokerect(canvas);
283 return;
284 }
285 if (false) { // avoid bit rot, suppress warning
286 test_text(canvas);
287 return;
288 }
289
290 const SkPoint origins[] = {
291 { 30*SK_Scalar1, 50*SK_Scalar1 },
292 { 150*SK_Scalar1, 50*SK_Scalar1 },
293 };
294 this->drawPredicates(canvas, origins);
295
296 static const struct {
297 SkColor fColor;
298 const char* fName;
299 SkRegion::Op fOp;
300 } gOps[] = {
301 { SK_ColorBLACK, "Difference", SkRegion::kDifference_Op },
302 { SK_ColorRED, "Intersect", SkRegion::kIntersect_Op },
303 { 0xFF008800, "Union", SkRegion::kUnion_Op },
304 { SK_ColorBLUE, "XOR", SkRegion::kXOR_Op }
305 };
306
307 SkFont font;
308 font.setSize(SK_Scalar1*24);
309
310 this->drawOrig(canvas, false);
311 canvas->save();
312 canvas->translate(SkIntToScalar(200), 0);
313 this->drawRgnOped(canvas, SkRegion::kUnion_Op, SK_ColorBLACK);
314 canvas->restore();
315
316 canvas->translate(0, SkIntToScalar(200));
317
318 for (size_t op = 0; op < SK_ARRAY_COUNT(gOps); op++) {
319 canvas->drawSimpleText(gOps[op].fName, strlen(gOps[op].fName), kUTF8_SkTextEncoding,
320 SkIntToScalar(75), SkIntToScalar(50), font, SkPaint());
321
322 this->drawRgnOped(canvas, gOps[op].fOp, gOps[op].fColor);
323
324 canvas->save();
325 canvas->translate(0, SkIntToScalar(200));
326 this->drawPathOped(canvas, gOps[op].fOp, gOps[op].fColor);
327 canvas->restore();
328
329 canvas->translate(SkIntToScalar(200), 0);
330 }
331 }
332
onFindClickHandler(SkScalar x,SkScalar y,unsigned modi)333 virtual Sample::Click* onFindClickHandler(SkScalar x, SkScalar y,
334 unsigned modi) override {
335 return fRect.contains(SkScalarRoundToInt(x),
336 SkScalarRoundToInt(y)) ? new Click(this) : nullptr;
337 }
338
onClick(Click * click)339 bool onClick(Click* click) override {
340 fRect.offset(click->fICurr.fX - click->fIPrev.fX,
341 click->fICurr.fY - click->fIPrev.fY);
342 return true;
343 }
344
345 private:
346 SkIRect fBase, fRect;
347
348 typedef Sample INHERITED;
349 };
350
351 //////////////////////////////////////////////////////////////////////////////
352
353 DEF_SAMPLE( return new RegionView(); )
354