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 "SkView.h"
10 #include "SkCanvas.h"
11 #include "SkGradientShader.h"
12 #include "SkMakeUnique.h"
13
make_grad(SkScalar w,SkScalar h)14 static sk_sp<SkShader> make_grad(SkScalar w, SkScalar h) {
15 SkColor colors[] = { 0xFF000000, 0xFF333333 };
16 SkPoint pts[] = { { 0, 0 }, { w, h } };
17 return SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
18 }
19
20 class BigGradientView : public SampleView {
21 public:
BigGradientView()22 BigGradientView() {}
23
24 protected:
onQuery(SkEvent * evt)25 bool onQuery(SkEvent* evt) override {
26 if (SampleCode::TitleQ(*evt)) {
27 SampleCode::TitleR(evt, "BigGradient");
28 return true;
29 }
30 return this->INHERITED::onQuery(evt);
31 }
32
onDrawContent(SkCanvas * canvas)33 void onDrawContent(SkCanvas* canvas) override {
34 SkRect r;
35 r.set(0, 0, this->width(), this->height());
36 SkPaint p;
37 p.setShader(make_grad(this->width(), this->height()));
38 canvas->drawRect(r, p);
39 }
40
41 private:
42 typedef SampleView INHERITED;
43 };
44
45 ///////////////////////////////////////////////////////////////////////////////
46
MyFactory()47 static SkView* MyFactory() { return new BigGradientView; }
48 static SkViewRegister reg(MyFactory);
49
50 ///////////////////////////////////////////////////////////////////////////////
51
52 #include "SkRasterHandleAllocator.h"
53
54 class GraphicsPort {
55 protected:
56 SkCanvas* fCanvas;
57
58 public:
GraphicsPort(SkCanvas * canvas)59 GraphicsPort(SkCanvas* canvas) : fCanvas(canvas) {}
~GraphicsPort()60 virtual ~GraphicsPort() {}
61
save()62 void save() { fCanvas->save(); }
saveLayer(const SkRect & bounds,SkAlpha alpha)63 void saveLayer(const SkRect& bounds, SkAlpha alpha) {
64 fCanvas->saveLayerAlpha(&bounds, alpha);
65 }
restore()66 void restore() { fCanvas->restore(); }
67
translate(float x,float y)68 void translate(float x, float y) { fCanvas->translate(x, y); }
scale(float s)69 void scale(float s) { fCanvas->scale(s, s); }
clip(const SkRect & r)70 void clip(const SkRect& r) { fCanvas->clipRect(r); }
71
drawOval(const SkRect & r,SkColor c)72 void drawOval(const SkRect& r, SkColor c) {
73 SkPaint p;
74 p.setColor(c);
75 fCanvas->drawOval(r, p);
76 }
77
drawRect(const SkRect & r,SkColor c)78 virtual void drawRect(const SkRect& r, SkColor c) {
79 SkPaint p;
80 p.setColor(c);
81 fCanvas->drawRect(r, p);
82 }
83
peekCanvas() const84 SkCanvas* peekCanvas() const { return fCanvas; }
85 };
86
87 #ifdef SK_BUILD_FOR_MAC
88
89 #include "SkCGUtils.h"
90 class CGGraphicsPort : public GraphicsPort {
91 public:
CGGraphicsPort(SkCanvas * canvas)92 CGGraphicsPort(SkCanvas* canvas) : GraphicsPort(canvas) {}
93
drawRect(const SkRect & r,SkColor c)94 void drawRect(const SkRect& r, SkColor c) override {
95 CGContextRef cg = (CGContextRef)fCanvas->accessTopRasterHandle();
96
97 CGColorRef color = CGColorCreateGenericRGB(SkColorGetR(c)/255.f,
98 SkColorGetG(c)/255.f,
99 SkColorGetB(c)/255.f,
100 SkColorGetA(c)/255.f);
101
102 CGContextSetFillColorWithColor(cg, color);
103 CGContextFillRect(cg, CGRectMake(r.x(), r.y(), r.width(), r.height()));
104 }
105 };
106
matrix_to_transform(CGContextRef cg,const SkMatrix & ctm)107 static CGAffineTransform matrix_to_transform(CGContextRef cg, const SkMatrix& ctm) {
108 SkMatrix matrix;
109 matrix.setScale(1, -1);
110 matrix.postTranslate(0, SkIntToScalar(CGBitmapContextGetHeight(cg)));
111 matrix.preConcat(ctm);
112
113 return CGAffineTransformMake(matrix[SkMatrix::kMScaleX],
114 matrix[SkMatrix::kMSkewY],
115 matrix[SkMatrix::kMSkewX],
116 matrix[SkMatrix::kMScaleY],
117 matrix[SkMatrix::kMTransX],
118 matrix[SkMatrix::kMTransY]);
119 }
120
121 class Allocator_CG : public SkRasterHandleAllocator {
122 public:
Allocator_CG()123 Allocator_CG() {}
124
allocHandle(const SkImageInfo & info,Rec * rec)125 bool allocHandle(const SkImageInfo& info, Rec* rec) override {
126 // let CG allocate the pixels
127 CGContextRef cg = SkCreateCGContext(SkPixmap(info, nullptr, 0));
128 if (!cg) {
129 return false;
130 }
131 rec->fReleaseProc = [](void* pixels, void* ctx){ CGContextRelease((CGContextRef)ctx); };
132 rec->fReleaseCtx = cg;
133 rec->fPixels = CGBitmapContextGetData(cg);
134 rec->fRowBytes = CGBitmapContextGetBytesPerRow(cg);
135 rec->fHandle = cg;
136 CGContextSaveGState(cg); // balanced each time updateContext is called
137 return true;
138 }
139
updateHandle(Handle hndl,const SkMatrix & ctm,const SkIRect & clip)140 void updateHandle(Handle hndl, const SkMatrix& ctm, const SkIRect& clip) override {
141 CGContextRef cg = (CGContextRef)hndl;
142
143 CGContextRestoreGState(cg);
144 CGContextSaveGState(cg);
145 CGContextClipToRect(cg, CGRectMake(clip.x(), clip.y(), clip.width(), clip.height()));
146 CGContextConcatCTM(cg, matrix_to_transform(cg, ctm));
147 }
148 };
149
150 #define MyPort CGGraphicsPort
151 #define MyAllocator Allocator_CG
152
153 #elif defined(WIN32)
154
toRECT(const SkIRect & r)155 static RECT toRECT(const SkIRect& r) {
156 return { r.left(), r.top(), r.right(), r.bottom() };
157 }
158
159 class GDIGraphicsPort : public GraphicsPort {
160 public:
GDIGraphicsPort(SkCanvas * canvas)161 GDIGraphicsPort(SkCanvas* canvas) : GraphicsPort(canvas) {}
162
drawRect(const SkRect & r,SkColor c)163 void drawRect(const SkRect& r, SkColor c) override {
164 HDC hdc = (HDC)fCanvas->accessTopRasterHandle();
165
166 COLORREF cr = RGB(SkColorGetR(c), SkColorGetG(c), SkColorGetB(c));// SkEndian_Swap32(c) >> 8;
167 FillRect(hdc, &toRECT(r.round()), CreateSolidBrush(cr));
168
169 // Assuming GDI wrote zeros for alpha, this will or-in 0xFF for alpha
170 SkPaint paint;
171 paint.setBlendMode(SkBlendMode::kDstATop);
172 fCanvas->drawRect(r, paint);
173 }
174 };
175
DeleteHDCCallback(void *,void * context)176 static void DeleteHDCCallback(void*, void* context) {
177 HDC hdc = static_cast<HDC>(context);
178 HBITMAP hbitmap = static_cast<HBITMAP>(SelectObject(hdc, nullptr));
179 DeleteObject(hbitmap);
180 DeleteDC(hdc);
181 }
182
183 // We use this static factory function instead of the regular constructor so
184 // that we can create the pixel data before calling the constructor. This is
185 // required so that we can call the base class' constructor with the pixel
186 // data.
Create(int width,int height,bool is_opaque,SkRasterHandleAllocator::Rec * rec)187 static bool Create(int width, int height, bool is_opaque, SkRasterHandleAllocator::Rec* rec) {
188 BITMAPINFOHEADER hdr = { 0 };
189 hdr.biSize = sizeof(BITMAPINFOHEADER);
190 hdr.biWidth = width;
191 hdr.biHeight = -height; // Minus means top-down bitmap.
192 hdr.biPlanes = 1;
193 hdr.biBitCount = 32;
194 hdr.biCompression = BI_RGB; // No compression.
195 hdr.biSizeImage = 0;
196 hdr.biXPelsPerMeter = 1;
197 hdr.biYPelsPerMeter = 1;
198 void* pixels;
199 HBITMAP hbitmap = CreateDIBSection(nullptr, (const BITMAPINFO*)&hdr, 0, &pixels, 0, 0);
200 if (!hbitmap) {
201 return false;
202 }
203
204 size_t row_bytes = width * sizeof(SkPMColor);
205 sk_bzero(pixels, row_bytes * height);
206
207 HDC hdc = CreateCompatibleDC(nullptr);
208 if (!hdc) {
209 DeleteObject(hbitmap);
210 return false;
211 }
212 SetGraphicsMode(hdc, GM_ADVANCED);
213 SelectObject(hdc, hbitmap);
214
215 rec->fReleaseProc = DeleteHDCCallback;
216 rec->fReleaseCtx = hdc;
217 rec->fPixels = pixels;
218 rec->fRowBytes = row_bytes;
219 rec->fHandle = hdc;
220 return true;
221 }
222
223 /**
224 * Subclass of SkRasterHandleAllocator that returns an HDC as its "handle".
225 */
226 class GDIAllocator : public SkRasterHandleAllocator {
227 public:
GDIAllocator()228 GDIAllocator() {}
229
allocHandle(const SkImageInfo & info,Rec * rec)230 bool allocHandle(const SkImageInfo& info, Rec* rec) override {
231 SkASSERT(info.colorType() == kN32_SkColorType);
232 return Create(info.width(), info.height(), info.isOpaque(), rec);
233 }
234
updateHandle(Handle handle,const SkMatrix & ctm,const SkIRect & clip_bounds)235 void updateHandle(Handle handle, const SkMatrix& ctm, const SkIRect& clip_bounds) override {
236 HDC hdc = static_cast<HDC>(handle);
237
238 XFORM xf;
239 xf.eM11 = ctm[SkMatrix::kMScaleX];
240 xf.eM21 = ctm[SkMatrix::kMSkewX];
241 xf.eDx = ctm[SkMatrix::kMTransX];
242 xf.eM12 = ctm[SkMatrix::kMSkewY];
243 xf.eM22 = ctm[SkMatrix::kMScaleY];
244 xf.eDy = ctm[SkMatrix::kMTransY];
245 SetWorldTransform(hdc, &xf);
246
247 HRGN hrgn = CreateRectRgnIndirect(&toRECT(clip_bounds));
248 int result = SelectClipRgn(hdc, hrgn);
249 SkASSERT(result != ERROR);
250 result = DeleteObject(hrgn);
251 SkASSERT(result != 0);
252 }
253 };
254
255 #define MyPort GDIGraphicsPort
256 #define MyAllocator GDIAllocator
257
258 #endif
259
260 #ifdef MyAllocator
261 class RasterAllocatorSample : public SampleView {
262 public:
RasterAllocatorSample()263 RasterAllocatorSample() {}
264
265 protected:
onQuery(SkEvent * evt)266 bool onQuery(SkEvent* evt) override {
267 if (SampleCode::TitleQ(*evt)) {
268 SampleCode::TitleR(evt, "raster-allocator");
269 return true;
270 }
271 return this->INHERITED::onQuery(evt);
272 }
273
doDraw(GraphicsPort * port)274 void doDraw(GraphicsPort* port) {
275 SkAutoCanvasRestore acr(port->peekCanvas(), true);
276
277 port->drawRect({0, 0, 256, 256}, SK_ColorRED);
278 port->save();
279 port->translate(30, 30);
280 port->drawRect({0, 0, 30, 30}, SK_ColorBLUE);
281 port->drawOval({10, 10, 20, 20}, SK_ColorWHITE);
282 port->restore();
283
284 port->saveLayer({50, 50, 100, 100}, 0x80);
285 port->drawRect({55, 55, 95, 95}, SK_ColorGREEN);
286 port->restore();
287
288 port->clip({150, 50, 200, 200});
289 port->drawRect({0, 0, 256, 256}, 0xFFCCCCCC);
290 }
291
onDrawContent(SkCanvas * canvas)292 void onDrawContent(SkCanvas* canvas) override {
293 GraphicsPort skp(canvas);
294 doDraw(&skp);
295
296 const SkImageInfo info = SkImageInfo::MakeN32Premul(256, 256);
297 std::unique_ptr<SkCanvas> c2 =
298 SkRasterHandleAllocator::MakeCanvas(skstd::make_unique<MyAllocator>(), info);
299 MyPort cgp(c2.get());
300 doDraw(&cgp);
301
302 SkPixmap pm;
303 c2->peekPixels(&pm);
304 SkBitmap bm;
305 bm.installPixels(pm);
306 canvas->drawBitmap(bm, 280, 0, nullptr);
307 }
308
309 private:
310 typedef SampleView INHERITED;
311 };
312 DEF_SAMPLE( return new RasterAllocatorSample; )
313 #endif
314