SkiaShader.cpp revision e3095e0c1e2a4a4f34f741aa386eae56536ca5aa 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <utils/Log.h>
20
21#include <SkMatrix.h>
22
23#include "SkiaShader.h"
24#include "Texture.h"
25#include "Matrix.h"
26
27namespace android {
28namespace uirenderer {
29
30///////////////////////////////////////////////////////////////////////////////
31// Support
32///////////////////////////////////////////////////////////////////////////////
33
34static const GLenum gTextureUnitsMap[] = {
35        GL_TEXTURE0,
36        GL_TEXTURE1,
37        GL_TEXTURE2
38};
39
40static const GLint gTileModes[] = {
41        GL_CLAMP_TO_EDGE,   // == SkShader::kClamp_TileMode
42        GL_REPEAT,          // == SkShader::kRepeat_Mode
43        GL_MIRRORED_REPEAT  // == SkShader::kMirror_TileMode
44};
45
46///////////////////////////////////////////////////////////////////////////////
47// Base shader
48///////////////////////////////////////////////////////////////////////////////
49
50SkiaShader::SkiaShader(Type type, SkShader* key, SkShader::TileMode tileX,
51        SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
52        mType(type), mKey(key), mTileX(tileX), mTileY(tileY), mMatrix(matrix), mBlend(blend) {
53}
54
55SkiaShader::~SkiaShader() {
56}
57
58void SkiaShader::describe(ProgramDescription& description, const Extensions& extensions) {
59}
60
61void SkiaShader::setupProgram(Program* program, const mat4& modelView, const Snapshot& snapshot,
62        GLuint* textureUnit) {
63}
64
65void SkiaShader::bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit) {
66    glActiveTexture(gTextureUnitsMap[textureUnit]);
67    glBindTexture(GL_TEXTURE_2D, texture);
68    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
69    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
70}
71
72///////////////////////////////////////////////////////////////////////////////
73// Bitmap shader
74///////////////////////////////////////////////////////////////////////////////
75
76SkiaBitmapShader::SkiaBitmapShader(SkBitmap* bitmap, SkShader* key, SkShader::TileMode tileX,
77        SkShader::TileMode tileY, SkMatrix* matrix, bool blend):
78        SkiaShader(kBitmap, key, tileX, tileY, matrix, blend), mBitmap(bitmap), mTexture(NULL) {
79}
80
81void SkiaBitmapShader::describe(ProgramDescription& description, const Extensions& extensions) {
82    const Texture* texture = mTextureCache->get(mBitmap);
83    if (!texture) return;
84    mTexture = texture;
85
86    const float width = texture->width;
87    const float height = texture->height;
88
89    description.hasBitmap = true;
90    // The driver does not support non-power of two mirrored/repeated
91    // textures, so do it ourselves
92    if (!extensions.hasNPot() && (!isPowerOfTwo(width) || !isPowerOfTwo(height)) &&
93            (mTileX != SkShader::kClamp_TileMode || mTileY != SkShader::kClamp_TileMode)) {
94        description.isBitmapNpot = true;
95        description.bitmapWrapS = gTileModes[mTileX];
96        description.bitmapWrapT = gTileModes[mTileY];
97        mWrapS = GL_CLAMP_TO_EDGE;
98        mWrapT = GL_CLAMP_TO_EDGE;
99    } else {
100        mWrapS = gTileModes[mTileX];
101        mWrapT = gTileModes[mTileY];
102    }
103}
104
105void SkiaBitmapShader::setupProgram(Program* program, const mat4& modelView,
106        const Snapshot& snapshot, GLuint* textureUnit) {
107    GLuint textureSlot = (*textureUnit)++;
108    glActiveTexture(gTextureUnitsMap[textureSlot]);
109
110    const Texture* texture = mTexture;
111    mTexture = NULL;
112    if (!texture) return;
113    const AutoTexture autoCleanup(texture);
114
115    const float width = texture->width;
116    const float height = texture->height;
117
118    mat4 textureTransform;
119    if (mMatrix) {
120        SkMatrix inverse;
121        mMatrix->invert(&inverse);
122        textureTransform.load(inverse);
123        textureTransform.multiply(modelView);
124    } else {
125        textureTransform.load(modelView);
126    }
127
128    // Uniforms
129    bindTexture(texture->id, mWrapS, mWrapT, textureSlot);
130    glUniform1i(program->getUniform("bitmapSampler"), textureSlot);
131    glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
132            GL_FALSE, &textureTransform.data[0]);
133    glUniform2f(program->getUniform("textureDimension"), 1.0f / width, 1.0f / height);
134}
135
136void SkiaBitmapShader::updateTransforms(Program* program, const mat4& modelView,
137        const Snapshot& snapshot) {
138    mat4 textureTransform;
139    if (mMatrix) {
140        SkMatrix inverse;
141        mMatrix->invert(&inverse);
142        textureTransform.load(inverse);
143        textureTransform.multiply(modelView);
144    } else {
145        textureTransform.load(modelView);
146    }
147
148    glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
149            GL_FALSE, &textureTransform.data[0]);
150}
151
152///////////////////////////////////////////////////////////////////////////////
153// Linear gradient shader
154///////////////////////////////////////////////////////////////////////////////
155
156static void toUnitMatrix(const SkPoint pts[2], SkMatrix* matrix) {
157    SkVector vec = pts[1] - pts[0];
158    const float mag = vec.length();
159    const float inv = mag ? 1.0f / mag : 0;
160
161    vec.scale(inv);
162    matrix->setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
163    matrix->postTranslate(-pts[0].fX, -pts[0].fY);
164    matrix->postScale(inv, inv);
165}
166
167SkiaLinearGradientShader::SkiaLinearGradientShader(float* bounds, uint32_t* colors,
168        float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
169        SkMatrix* matrix, bool blend):
170        SkiaShader(kLinearGradient, key, tileMode, tileMode, matrix, blend),
171        mBounds(bounds), mColors(colors), mPositions(positions), mCount(count) {
172    SkPoint points[2];
173    points[0].set(bounds[0], bounds[1]);
174    points[1].set(bounds[2], bounds[3]);
175
176    SkMatrix unitMatrix;
177    toUnitMatrix(points, &unitMatrix);
178    mUnitMatrix.load(unitMatrix);
179
180    updateLocalMatrix(matrix);
181}
182
183SkiaLinearGradientShader::~SkiaLinearGradientShader() {
184    delete[] mBounds;
185    delete[] mColors;
186    delete[] mPositions;
187}
188
189void SkiaLinearGradientShader::describe(ProgramDescription& description,
190        const Extensions& extensions) {
191    description.hasGradient = true;
192    description.gradientType = ProgramDescription::kGradientLinear;
193}
194
195void SkiaLinearGradientShader::computeScreenSpaceMatrix(mat4& screenSpace, const mat4& modelView) {
196    screenSpace.loadMultiply(mUnitMatrix, mShaderMatrix);
197    screenSpace.multiply(modelView);
198}
199
200void SkiaLinearGradientShader::updateLocalMatrix(const SkMatrix* matrix) {
201    if (matrix) {
202        mat4 localMatrix(*matrix);
203        mShaderMatrix.loadInverse(localMatrix);
204    }
205}
206
207void SkiaLinearGradientShader::setMatrix(SkMatrix* matrix) {
208    SkiaShader::setMatrix(matrix);
209    updateLocalMatrix(matrix);
210}
211
212void SkiaLinearGradientShader::setupProgram(Program* program, const mat4& modelView,
213        const Snapshot& snapshot, GLuint* textureUnit) {
214    GLuint textureSlot = (*textureUnit)++;
215    glActiveTexture(gTextureUnitsMap[textureSlot]);
216
217    Texture* texture = mGradientCache->get(mKey);
218    if (!texture) {
219        texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount, mTileX);
220    }
221
222    mat4 screenSpace;
223    computeScreenSpaceMatrix(screenSpace, modelView);
224
225    // Uniforms
226    bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
227    glUniform1i(program->getUniform("gradientSampler"), textureSlot);
228    glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
229}
230
231void SkiaLinearGradientShader::updateTransforms(Program* program, const mat4& modelView,
232        const Snapshot& snapshot) {
233    mat4 screenSpace;
234    computeScreenSpaceMatrix(screenSpace, modelView);
235    glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
236}
237
238///////////////////////////////////////////////////////////////////////////////
239// Circular gradient shader
240///////////////////////////////////////////////////////////////////////////////
241
242SkiaCircularGradientShader::SkiaCircularGradientShader(float x, float y, float radius,
243        uint32_t* colors, float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
244        SkMatrix* matrix, bool blend):
245        SkiaSweepGradientShader(kCircularGradient, x, y, colors, positions, count, key,
246                tileMode, matrix, blend),
247        mRadius(radius) {
248}
249
250void SkiaCircularGradientShader::describe(ProgramDescription& description,
251        const Extensions& extensions) {
252    description.hasGradient = true;
253    description.gradientType = ProgramDescription::kGradientCircular;
254}
255
256void SkiaCircularGradientShader::setupProgram(Program* program, const mat4& modelView,
257        const Snapshot& snapshot, GLuint* textureUnit) {
258    SkiaSweepGradientShader::setupProgram(program, modelView, snapshot, textureUnit);
259    glUniform1f(program->getUniform("gradientRadius"), 1.0f / mRadius);
260}
261
262///////////////////////////////////////////////////////////////////////////////
263// Sweep gradient shader
264///////////////////////////////////////////////////////////////////////////////
265
266SkiaSweepGradientShader::SkiaSweepGradientShader(float x, float y, uint32_t* colors,
267        float* positions, int count, SkShader* key, SkMatrix* matrix, bool blend):
268        SkiaShader(kSweepGradient, key, SkShader::kClamp_TileMode,
269                SkShader::kClamp_TileMode, matrix, blend),
270        mX(x), mY(y), mColors(colors), mPositions(positions), mCount(count) {
271}
272
273SkiaSweepGradientShader::SkiaSweepGradientShader(Type type, float x, float y, uint32_t* colors,
274        float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
275        SkMatrix* matrix, bool blend):
276        SkiaShader(type, key, tileMode, tileMode, matrix, blend),
277        mX(x), mY(y), mColors(colors), mPositions(positions), mCount(count) {
278}
279
280SkiaSweepGradientShader::~SkiaSweepGradientShader() {
281    delete[] mColors;
282    delete[] mPositions;
283}
284
285void SkiaSweepGradientShader::describe(ProgramDescription& description,
286        const Extensions& extensions) {
287    description.hasGradient = true;
288    description.gradientType = ProgramDescription::kGradientSweep;
289}
290
291void SkiaSweepGradientShader::setupProgram(Program* program, const mat4& modelView,
292        const Snapshot& snapshot, GLuint* textureUnit) {
293    GLuint textureSlot = (*textureUnit)++;
294    glActiveTexture(gTextureUnitsMap[textureSlot]);
295
296    Texture* texture = mGradientCache->get(mKey);
297    if (!texture) {
298        texture = mGradientCache->addLinearGradient(mKey, mColors, mPositions, mCount);
299    }
300
301    float left = mX;
302    float top = mY;
303
304    mat4 shaderMatrix;
305    if (mMatrix) {
306        shaderMatrix.load(*mMatrix);
307        shaderMatrix.mapPoint(left, top);
308    }
309
310    mat4 copy(shaderMatrix);
311    shaderMatrix.loadInverse(copy);
312
313    snapshot.transform->mapPoint(left, top);
314
315    mat4 screenSpace(*snapshot.transform);
316    screenSpace.multiply(modelView);
317
318    // Uniforms
319    bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
320    glUniform1i(program->getUniform("gradientSampler"), textureSlot);
321    glUniformMatrix4fv(program->getUniform("gradientMatrix"), 1, GL_FALSE, &shaderMatrix.data[0]);
322    glUniform2f(program->getUniform("gradientStart"), left, top);
323    glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
324}
325
326void SkiaSweepGradientShader::updateTransforms(Program* program, const mat4& modelView,
327        const Snapshot& snapshot) {
328    mat4 screenSpace(*snapshot.transform);
329    screenSpace.multiply(modelView);
330    glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
331}
332
333///////////////////////////////////////////////////////////////////////////////
334// Compose shader
335///////////////////////////////////////////////////////////////////////////////
336
337SkiaComposeShader::SkiaComposeShader(SkiaShader* first, SkiaShader* second,
338        SkXfermode::Mode mode, SkShader* key):
339        SkiaShader(kCompose, key, SkShader::kClamp_TileMode, SkShader::kClamp_TileMode,
340        NULL, first->blend() || second->blend()), mFirst(first), mSecond(second), mMode(mode) {
341}
342
343void SkiaComposeShader::set(TextureCache* textureCache, GradientCache* gradientCache) {
344    SkiaShader::set(textureCache, gradientCache);
345    mFirst->set(textureCache, gradientCache);
346    mSecond->set(textureCache, gradientCache);
347}
348
349void SkiaComposeShader::describe(ProgramDescription& description, const Extensions& extensions) {
350    mFirst->describe(description, extensions);
351    mSecond->describe(description, extensions);
352    if (mFirst->type() == kBitmap) {
353        description.isBitmapFirst = true;
354    }
355    description.shadersMode = mMode;
356}
357
358void SkiaComposeShader::setupProgram(Program* program, const mat4& modelView,
359        const Snapshot& snapshot, GLuint* textureUnit) {
360    mFirst->setupProgram(program, modelView, snapshot, textureUnit);
361    mSecond->setupProgram(program, modelView, snapshot, textureUnit);
362}
363
364}; // namespace uirenderer
365}; // namespace android
366