SkiaShader.cpp revision a48a1a87ba17f20f7006eaab21dcedf86c015c13 
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    }
98}
99
100void SkiaBitmapShader::setupProgram(Program* program, const mat4& modelView,
101        const Snapshot& snapshot, GLuint* textureUnit) {
102    GLuint textureSlot = (*textureUnit)++;
103    glActiveTexture(gTextureUnitsMap[textureSlot]);
104
105    const Texture* texture = mTexture;
106    mTexture = NULL;
107    if (!texture) return;
108    const AutoTexture autoCleanup(texture);
109
110    const float width = texture->width;
111    const float height = texture->height;
112
113    mat4 textureTransform;
114    if (mMatrix) {
115        SkMatrix inverse;
116        mMatrix->invert(&inverse);
117        textureTransform.load(inverse);
118        textureTransform.multiply(modelView);
119    } else {
120        textureTransform.load(modelView);
121    }
122
123    // Uniforms
124    bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
125    glUniform1i(program->getUniform("bitmapSampler"), textureSlot);
126    glUniformMatrix4fv(program->getUniform("textureTransform"), 1,
127            GL_FALSE, &textureTransform.data[0]);
128    glUniform2f(program->getUniform("textureDimension"), 1.0f / width, 1.0f / height);
129}
130
131///////////////////////////////////////////////////////////////////////////////
132// Linear gradient shader
133///////////////////////////////////////////////////////////////////////////////
134
135SkiaLinearGradientShader::SkiaLinearGradientShader(float* bounds, uint32_t* colors,
136        float* positions, int count, SkShader* key, SkShader::TileMode tileMode,
137        SkMatrix* matrix, bool blend):
138        SkiaShader(kLinearGradient, key, tileMode, tileMode, matrix, blend),
139        mBounds(bounds), mColors(colors), mPositions(positions), mCount(count) {
140}
141
142SkiaLinearGradientShader::~SkiaLinearGradientShader() {
143    delete[] mBounds;
144    delete[] mColors;
145    delete[] mPositions;
146}
147
148void SkiaLinearGradientShader::describe(ProgramDescription& description,
149        const Extensions& extensions) {
150    description.hasGradient = true;
151}
152
153void SkiaLinearGradientShader::setupProgram(Program* program, const mat4& modelView,
154        const Snapshot& snapshot, GLuint* textureUnit) {
155    GLuint textureSlot = (*textureUnit)++;
156    glActiveTexture(gTextureUnitsMap[textureSlot]);
157
158    Texture* texture = mGradientCache->get(mKey);
159    if (!texture) {
160        texture = mGradientCache->addLinearGradient(mKey, mBounds, mColors, mPositions,
161                mCount, mTileX);
162    }
163
164    Rect start(mBounds[0], mBounds[1], mBounds[2], mBounds[3]);
165    if (mMatrix) {
166        mat4 shaderMatrix(*mMatrix);
167        shaderMatrix.mapRect(start);
168    }
169    snapshot.transform.mapRect(start);
170
171    const float gradientX = start.right - start.left;
172    const float gradientY = start.bottom - start.top;
173
174    mat4 screenSpace(snapshot.transform);
175    screenSpace.multiply(modelView);
176
177    // Uniforms
178    bindTexture(texture->id, gTileModes[mTileX], gTileModes[mTileY], textureSlot);
179    glUniform1i(program->getUniform("gradientSampler"), textureSlot);
180    glUniform2f(program->getUniform("gradientStart"), start.left, start.top);
181    glUniform2f(program->getUniform("gradient"), gradientX, gradientY);
182    glUniform1f(program->getUniform("gradientLength"),
183            1.0f / (gradientX * gradientX + gradientY * gradientY));
184    glUniformMatrix4fv(program->getUniform("screenSpace"), 1, GL_FALSE, &screenSpace.data[0]);
185}
186
187///////////////////////////////////////////////////////////////////////////////
188// Compose shader
189///////////////////////////////////////////////////////////////////////////////
190
191SkiaComposeShader::SkiaComposeShader(SkiaShader* first, SkiaShader* second,
192        SkXfermode::Mode mode, SkShader* key):
193        SkiaShader(kCompose, key, SkShader::kClamp_TileMode, SkShader::kClamp_TileMode,
194        NULL, first->blend() || second->blend()), mFirst(first), mSecond(second), mMode(mode) {
195}
196
197void SkiaComposeShader::set(TextureCache* textureCache, GradientCache* gradientCache) {
198    SkiaShader::set(textureCache, gradientCache);
199    mFirst->set(textureCache, gradientCache);
200    mSecond->set(textureCache, gradientCache);
201}
202
203void SkiaComposeShader::describe(ProgramDescription& description, const Extensions& extensions) {
204    mFirst->describe(description, extensions);
205    mSecond->describe(description, extensions);
206    if (mFirst->type() == kBitmap) {
207        description.isBitmapFirst = true;
208    }
209    description.shadersMode = mMode;
210}
211
212void SkiaComposeShader::setupProgram(Program* program, const mat4& modelView,
213        const Snapshot& snapshot, GLuint* textureUnit) {
214    mFirst->setupProgram(program, modelView, snapshot, textureUnit);
215    mSecond->setupProgram(program, modelView, snapshot, textureUnit);
216}
217
218}; // namespace uirenderer
219}; // namespace android
220