1 /*
2 * Copyright 2012 The Android Open Source Project
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 "SkBitmap.h"
9 #include "SkMagnifierImageFilter.h"
10 #include "SkColorPriv.h"
11 #include "SkDevice.h"
12 #include "SkReadBuffer.h"
13 #include "SkWriteBuffer.h"
14 #include "SkValidationUtils.h"
15
16 ////////////////////////////////////////////////////////////////////////////////
17 #if SK_SUPPORT_GPU
18 #include "GrInvariantOutput.h"
19 #include "effects/GrSingleTextureEffect.h"
20 #include "glsl/GrGLSLFragmentProcessor.h"
21 #include "glsl/GrGLSLFragmentShaderBuilder.h"
22 #include "glsl/GrGLSLProgramDataManager.h"
23 #include "glsl/GrGLSLUniformHandler.h"
24
25 class GrMagnifierEffect : public GrSingleTextureEffect {
26
27 public:
Create(GrTexture * texture,const SkRect & bounds,float xOffset,float yOffset,float xInvZoom,float yInvZoom,float xInvInset,float yInvInset)28 static GrFragmentProcessor* Create(GrTexture* texture,
29 const SkRect& bounds,
30 float xOffset,
31 float yOffset,
32 float xInvZoom,
33 float yInvZoom,
34 float xInvInset,
35 float yInvInset) {
36 return new GrMagnifierEffect(texture, bounds, xOffset, yOffset, xInvZoom, yInvZoom, xInvInset,
37 yInvInset);
38 }
39
~GrMagnifierEffect()40 virtual ~GrMagnifierEffect() {};
41
name() const42 const char* name() const override { return "Magnifier"; }
43
bounds() const44 const SkRect& bounds() const { return fBounds; } // Bounds of source image.
45 // Offset to apply to zoomed pixels, (srcRect position / texture size).
x_offset() const46 float x_offset() const { return fXOffset; }
y_offset() const47 float y_offset() const { return fYOffset; }
48
49 // Scale to apply to zoomed pixels (srcRect size / bounds size).
x_inv_zoom() const50 float x_inv_zoom() const { return fXInvZoom; }
y_inv_zoom() const51 float y_inv_zoom() const { return fYInvZoom; }
52
53 // 1/radius over which to transition from unzoomed to zoomed pixels (bounds size / inset).
x_inv_inset() const54 float x_inv_inset() const { return fXInvInset; }
y_inv_inset() const55 float y_inv_inset() const { return fYInvInset; }
56
57 private:
GrMagnifierEffect(GrTexture * texture,const SkRect & bounds,float xOffset,float yOffset,float xInvZoom,float yInvZoom,float xInvInset,float yInvInset)58 GrMagnifierEffect(GrTexture* texture,
59 const SkRect& bounds,
60 float xOffset,
61 float yOffset,
62 float xInvZoom,
63 float yInvZoom,
64 float xInvInset,
65 float yInvInset)
66 : INHERITED(texture, GrCoordTransform::MakeDivByTextureWHMatrix(texture))
67 , fBounds(bounds)
68 , fXOffset(xOffset)
69 , fYOffset(yOffset)
70 , fXInvZoom(xInvZoom)
71 , fYInvZoom(yInvZoom)
72 , fXInvInset(xInvInset)
73 , fYInvInset(yInvInset) {
74 this->initClassID<GrMagnifierEffect>();
75 }
76
77 GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
78
79 void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
80
81 bool onIsEqual(const GrFragmentProcessor&) const override;
82
83 void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
84
85 GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
86
87 SkRect fBounds;
88 float fXOffset;
89 float fYOffset;
90 float fXInvZoom;
91 float fYInvZoom;
92 float fXInvInset;
93 float fYInvInset;
94
95 typedef GrSingleTextureEffect INHERITED;
96 };
97
98 // For brevity
99 typedef GrGLSLProgramDataManager::UniformHandle UniformHandle;
100
101 class GrGLMagnifierEffect : public GrGLSLFragmentProcessor {
102 public:
103 void emitCode(EmitArgs&) override;
104
105 protected:
106 void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override;
107
108 private:
109 UniformHandle fOffsetVar;
110 UniformHandle fInvZoomVar;
111 UniformHandle fInvInsetVar;
112 UniformHandle fBoundsVar;
113
114 typedef GrGLSLFragmentProcessor INHERITED;
115 };
116
emitCode(EmitArgs & args)117 void GrGLMagnifierEffect::emitCode(EmitArgs& args) {
118 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
119 fOffsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
120 kVec2f_GrSLType, kDefault_GrSLPrecision,
121 "Offset");
122 fInvZoomVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
123 kVec2f_GrSLType, kDefault_GrSLPrecision,
124 "InvZoom");
125 fInvInsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
126 kVec2f_GrSLType, kDefault_GrSLPrecision,
127 "InvInset");
128 fBoundsVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
129 kVec4f_GrSLType, kDefault_GrSLPrecision,
130 "Bounds");
131
132 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
133 SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
134 fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
135 fragBuilder->codeAppendf("\t\tvec2 zoom_coord = %s + %s * %s;\n",
136 uniformHandler->getUniformCStr(fOffsetVar),
137 coords2D.c_str(),
138 uniformHandler->getUniformCStr(fInvZoomVar));
139 const char* bounds = uniformHandler->getUniformCStr(fBoundsVar);
140 fragBuilder->codeAppendf("\t\tvec2 delta = (coord - %s.xy) * %s.zw;\n", bounds, bounds);
141 fragBuilder->codeAppendf("\t\tdelta = min(delta, vec2(1.0, 1.0) - delta);\n");
142 fragBuilder->codeAppendf("\t\tdelta = delta * %s;\n",
143 uniformHandler->getUniformCStr(fInvInsetVar));
144
145 fragBuilder->codeAppend("\t\tfloat weight = 0.0;\n");
146 fragBuilder->codeAppend("\t\tif (delta.s < 2.0 && delta.t < 2.0) {\n");
147 fragBuilder->codeAppend("\t\t\tdelta = vec2(2.0, 2.0) - delta;\n");
148 fragBuilder->codeAppend("\t\t\tfloat dist = length(delta);\n");
149 fragBuilder->codeAppend("\t\t\tdist = max(2.0 - dist, 0.0);\n");
150 fragBuilder->codeAppend("\t\t\tweight = min(dist * dist, 1.0);\n");
151 fragBuilder->codeAppend("\t\t} else {\n");
152 fragBuilder->codeAppend("\t\t\tvec2 delta_squared = delta * delta;\n");
153 fragBuilder->codeAppend("\t\t\tweight = min(min(delta_squared.x, delta_squared.y), 1.0);\n");
154 fragBuilder->codeAppend("\t\t}\n");
155
156 fragBuilder->codeAppend("\t\tvec2 mix_coord = mix(coord, zoom_coord, weight);\n");
157 fragBuilder->codeAppend("\t\tvec4 output_color = ");
158 fragBuilder->appendTextureLookup(args.fSamplers[0], "mix_coord");
159 fragBuilder->codeAppend(";\n");
160
161 fragBuilder->codeAppendf("\t\t%s = output_color;", args.fOutputColor);
162 SkString modulate;
163 GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
164 fragBuilder->codeAppend(modulate.c_str());
165 }
166
onSetData(const GrGLSLProgramDataManager & pdman,const GrProcessor & effect)167 void GrGLMagnifierEffect::onSetData(const GrGLSLProgramDataManager& pdman,
168 const GrProcessor& effect) {
169 const GrMagnifierEffect& zoom = effect.cast<GrMagnifierEffect>();
170 pdman.set2f(fOffsetVar, zoom.x_offset(), zoom.y_offset());
171 pdman.set2f(fInvZoomVar, zoom.x_inv_zoom(), zoom.y_inv_zoom());
172 pdman.set2f(fInvInsetVar, zoom.x_inv_inset(), zoom.y_inv_inset());
173 pdman.set4f(fBoundsVar, zoom.bounds().x(), zoom.bounds().y(),
174 zoom.bounds().width(), zoom.bounds().height());
175 }
176
177 /////////////////////////////////////////////////////////////////////
178
onGetGLSLProcessorKey(const GrGLSLCaps & caps,GrProcessorKeyBuilder * b) const179 void GrMagnifierEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
180 GrProcessorKeyBuilder* b) const {
181 GrGLMagnifierEffect::GenKey(*this, caps, b);
182 }
183
onCreateGLSLInstance() const184 GrGLSLFragmentProcessor* GrMagnifierEffect::onCreateGLSLInstance() const {
185 return new GrGLMagnifierEffect;
186 }
187
188 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrMagnifierEffect);
189
TestCreate(GrProcessorTestData * d)190 const GrFragmentProcessor* GrMagnifierEffect::TestCreate(GrProcessorTestData* d) {
191 GrTexture* texture = d->fTextures[0];
192 const int kMaxWidth = 200;
193 const int kMaxHeight = 200;
194 const int kMaxInset = 20;
195 uint32_t width = d->fRandom->nextULessThan(kMaxWidth);
196 uint32_t height = d->fRandom->nextULessThan(kMaxHeight);
197 uint32_t x = d->fRandom->nextULessThan(kMaxWidth - width);
198 uint32_t y = d->fRandom->nextULessThan(kMaxHeight - height);
199 uint32_t inset = d->fRandom->nextULessThan(kMaxInset);
200
201 GrFragmentProcessor* effect = GrMagnifierEffect::Create(
202 texture,
203 SkRect::MakeWH(SkIntToScalar(kMaxWidth), SkIntToScalar(kMaxHeight)),
204 (float) width / texture->width(),
205 (float) height / texture->height(),
206 texture->width() / (float) x,
207 texture->height() / (float) y,
208 (float) inset / texture->width(),
209 (float) inset / texture->height());
210 SkASSERT(effect);
211 return effect;
212 }
213
214 ///////////////////////////////////////////////////////////////////////////////
215
onIsEqual(const GrFragmentProcessor & sBase) const216 bool GrMagnifierEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
217 const GrMagnifierEffect& s = sBase.cast<GrMagnifierEffect>();
218 return (this->fBounds == s.fBounds &&
219 this->fXOffset == s.fXOffset &&
220 this->fYOffset == s.fYOffset &&
221 this->fXInvZoom == s.fXInvZoom &&
222 this->fYInvZoom == s.fYInvZoom &&
223 this->fXInvInset == s.fXInvInset &&
224 this->fYInvInset == s.fYInvInset);
225 }
226
onComputeInvariantOutput(GrInvariantOutput * inout) const227 void GrMagnifierEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
228 this->updateInvariantOutputForModulation(inout);
229 }
230
231 #endif
232
233 ////////////////////////////////////////////////////////////////////////////////
234
Create(const SkRect & srcRect,SkScalar inset,SkImageFilter * input)235 SkImageFilter* SkMagnifierImageFilter::Create(const SkRect& srcRect, SkScalar inset,
236 SkImageFilter* input) {
237
238 if (!SkScalarIsFinite(inset) || !SkIsValidRect(srcRect)) {
239 return nullptr;
240 }
241 // Negative numbers in src rect are not supported
242 if (srcRect.fLeft < 0 || srcRect.fTop < 0) {
243 return nullptr;
244 }
245 return new SkMagnifierImageFilter(srcRect, inset, input);
246 }
247
248
SkMagnifierImageFilter(const SkRect & srcRect,SkScalar inset,SkImageFilter * input)249 SkMagnifierImageFilter::SkMagnifierImageFilter(const SkRect& srcRect, SkScalar inset,
250 SkImageFilter* input)
251 : INHERITED(1, &input), fSrcRect(srcRect), fInset(inset) {
252 SkASSERT(srcRect.x() >= 0 && srcRect.y() >= 0 && inset >= 0);
253 }
254
255 #if SK_SUPPORT_GPU
asFragmentProcessor(GrFragmentProcessor ** fp,GrTexture * texture,const SkMatrix &,const SkIRect & bounds) const256 bool SkMagnifierImageFilter::asFragmentProcessor(GrFragmentProcessor** fp,
257 GrTexture* texture, const SkMatrix&,
258 const SkIRect&bounds) const {
259 if (fp) {
260 SkScalar yOffset = texture->origin() == kTopLeft_GrSurfaceOrigin ? fSrcRect.y() :
261 texture->height() - fSrcRect.height() * texture->height() / bounds.height()
262 - fSrcRect.y();
263 int boundsY = (texture->origin() == kTopLeft_GrSurfaceOrigin) ? bounds.y() :
264 (texture->height() - bounds.height());
265 SkRect effectBounds = SkRect::MakeXYWH(
266 SkIntToScalar(bounds.x()) / texture->width(),
267 SkIntToScalar(boundsY) / texture->height(),
268 SkIntToScalar(texture->width()) / bounds.width(),
269 SkIntToScalar(texture->height()) / bounds.height());
270 SkScalar invInset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1;
271 *fp = GrMagnifierEffect::Create(texture,
272 effectBounds,
273 fSrcRect.x() / texture->width(),
274 yOffset / texture->height(),
275 fSrcRect.width() / bounds.width(),
276 fSrcRect.height() / bounds.height(),
277 bounds.width() * invInset,
278 bounds.height() * invInset);
279 }
280 return true;
281 }
282 #endif
283
CreateProc(SkReadBuffer & buffer)284 SkFlattenable* SkMagnifierImageFilter::CreateProc(SkReadBuffer& buffer) {
285 SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
286 SkRect src;
287 buffer.readRect(&src);
288 return Create(src, buffer.readScalar(), common.getInput(0));
289 }
290
flatten(SkWriteBuffer & buffer) const291 void SkMagnifierImageFilter::flatten(SkWriteBuffer& buffer) const {
292 this->INHERITED::flatten(buffer);
293 buffer.writeRect(fSrcRect);
294 buffer.writeScalar(fInset);
295 }
296
onFilterImageDeprecated(Proxy * proxy,const SkBitmap & src,const Context &,SkBitmap * dst,SkIPoint * offset) const297 bool SkMagnifierImageFilter::onFilterImageDeprecated(Proxy* proxy, const SkBitmap& src,
298 const Context&, SkBitmap* dst,
299 SkIPoint* offset) const {
300 if ((src.colorType() != kN32_SkColorType) ||
301 (fSrcRect.width() >= src.width()) ||
302 (fSrcRect.height() >= src.height())) {
303 return false;
304 }
305
306 SkAutoLockPixels alp(src);
307 SkASSERT(src.getPixels());
308 if (!src.getPixels() || src.width() <= 0 || src.height() <= 0) {
309 return false;
310 }
311
312 SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(src.width(), src.height()));
313 if (!device) {
314 return false;
315 }
316 *dst = device->accessBitmap(false);
317 SkAutoLockPixels alp_dst(*dst);
318
319 SkScalar inv_inset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1;
320
321 SkScalar inv_x_zoom = fSrcRect.width() / src.width();
322 SkScalar inv_y_zoom = fSrcRect.height() / src.height();
323
324 SkColor* sptr = src.getAddr32(0, 0);
325 SkColor* dptr = dst->getAddr32(0, 0);
326 int width = src.width(), height = src.height();
327 for (int y = 0; y < height; ++y) {
328 for (int x = 0; x < width; ++x) {
329 SkScalar x_dist = SkMin32(x, width - x - 1) * inv_inset;
330 SkScalar y_dist = SkMin32(y, height - y - 1) * inv_inset;
331 SkScalar weight = 0;
332
333 static const SkScalar kScalar2 = SkScalar(2);
334
335 // To create a smooth curve at the corners, we need to work on
336 // a square twice the size of the inset.
337 if (x_dist < kScalar2 && y_dist < kScalar2) {
338 x_dist = kScalar2 - x_dist;
339 y_dist = kScalar2 - y_dist;
340
341 SkScalar dist = SkScalarSqrt(SkScalarSquare(x_dist) +
342 SkScalarSquare(y_dist));
343 dist = SkMaxScalar(kScalar2 - dist, 0);
344 weight = SkMinScalar(SkScalarSquare(dist), SK_Scalar1);
345 } else {
346 SkScalar sqDist = SkMinScalar(SkScalarSquare(x_dist),
347 SkScalarSquare(y_dist));
348 weight = SkMinScalar(sqDist, SK_Scalar1);
349 }
350
351 SkScalar x_interp = SkScalarMul(weight, (fSrcRect.x() + x * inv_x_zoom)) +
352 (SK_Scalar1 - weight) * x;
353 SkScalar y_interp = SkScalarMul(weight, (fSrcRect.y() + y * inv_y_zoom)) +
354 (SK_Scalar1 - weight) * y;
355
356 int x_val = SkTPin(SkScalarFloorToInt(x_interp), 0, width - 1);
357 int y_val = SkTPin(SkScalarFloorToInt(y_interp), 0, height - 1);
358
359 *dptr = sptr[y_val * width + x_val];
360 dptr++;
361 }
362 }
363 return true;
364 }
365
366 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const367 void SkMagnifierImageFilter::toString(SkString* str) const {
368 str->appendf("SkMagnifierImageFilter: (");
369 str->appendf("src: (%f,%f,%f,%f) ",
370 fSrcRect.fLeft, fSrcRect.fTop, fSrcRect.fRight, fSrcRect.fBottom);
371 str->appendf("inset: %f", fInset);
372 str->append(")");
373 }
374 #endif
375