ProgramCache.cpp revision db1938e0e6ef816e228c815adccebd5cb05f2aa8 
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/String8.h>
20
21#include "ProgramCache.h"
22
23namespace android {
24namespace uirenderer {
25
26///////////////////////////////////////////////////////////////////////////////
27// Vertex shaders snippets
28///////////////////////////////////////////////////////////////////////////////
29
30const char* gVS_Header_Attributes =
31        "attribute vec4 position;\n";
32const char* gVS_Header_Attributes_TexCoords =
33        "attribute vec2 texCoords;\n";
34const char* gVS_Header_Uniforms =
35        "uniform mat4 transform;\n";
36const char* gVS_Header_Uniforms_HasGradient =
37        "uniform float gradientLength;\n"
38        "uniform vec2 gradient;\n"
39        "uniform vec2 gradientStart;\n"
40        "uniform mat4 screenSpace;\n";
41const char* gVS_Header_Uniforms_HasBitmap =
42        "uniform mat4 textureTransform;\n"
43        "uniform vec2 textureDimension;\n";
44const char* gVS_Header_Varyings_HasTexture =
45        "varying vec2 outTexCoords;\n";
46const char* gVS_Header_Varyings_HasBitmap =
47        "varying vec2 outBitmapTexCoords;\n";
48const char* gVS_Header_Varyings_HasGradient =
49        "varying float index;\n";
50const char* gVS_Main =
51        "\nvoid main(void) {\n";
52const char* gVS_Main_OutTexCoords =
53        "    outTexCoords = texCoords;\n";
54const char* gVS_Main_OutGradientIndex =
55        "    vec4 location = screenSpace * position;\n"
56        "    index = dot(location.xy - gradientStart, gradient) * gradientLength;\n";
57const char* gVS_Main_OutBitmapTexCoords =
58        "    vec4 bitmapCoords = textureTransform * position;\n"
59        "    outBitmapTexCoords = bitmapCoords.xy * textureDimension;\n";
60const char* gVS_Main_Position =
61        "    gl_Position = transform * position;\n";
62const char* gVS_Footer =
63        "}\n\n";
64
65///////////////////////////////////////////////////////////////////////////////
66// Fragment shaders snippets
67///////////////////////////////////////////////////////////////////////////////
68
69const char* gFS_Header =
70        "precision mediump float;\n\n";
71const char* gFS_Uniforms_Color =
72        "uniform vec4 color;\n";
73const char* gFS_Uniforms_TextureSampler =
74        "uniform sampler2D sampler;\n";
75const char* gFS_Uniforms_GradientSampler =
76        "uniform sampler2D gradientSampler;\n";
77const char* gFS_Uniforms_BitmapSampler =
78        "uniform sampler2D bitmapSampler;\n";
79const char* gFS_Uniforms_ColorOp[4] = {
80        // None
81        "",
82        // Matrix
83        "uniform mat4 colorMatrix;\n"
84        "uniform vec4 colorMatrixVector;\n",
85        // Lighting
86        "uniform vec4 lightingMul;\n"
87        "uniform vec4 lightingAdd;\n",
88        // PorterDuff
89        "uniform vec4 colorBlend;\n"
90};
91const char* gFS_Main =
92        "\nvoid main(void) {\n"
93        "    vec4 fragColor;\n";
94const char* gFS_Main_FetchColor =
95        "    fragColor = color;\n";
96const char* gFS_Main_FetchTexture =
97        "    fragColor = color * texture2D(sampler, outTexCoords);\n";
98const char* gFS_Main_FetchA8Texture =
99        "    fragColor = color * texture2D(sampler, outTexCoords).a;\n";
100const char* gFS_Main_FetchGradient =
101        "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n";
102const char* gFS_Main_FetchBitmap =
103        "    vec4 bitmapColor = texture2D(bitmapSampler, outBitmapTexCoords);\n";
104const char* gFS_Main_FetchBitmapNpot =
105        "    vec4 bitmapColor = texture2D(bitmapSampler, wrap(outBitmapTexCoords));\n";
106const char* gFS_Main_BlendShadersBG =
107        "    fragColor = blendShaders(gradientColor, bitmapColor)";
108const char* gFS_Main_BlendShadersGB =
109        "    fragColor = blendShaders(bitmapColor, gradientColor)";
110const char* gFS_Main_BlendShaders_Modulate =
111        " * fragColor.a;\n";
112const char* gFS_Main_GradientShader_Modulate =
113        "    fragColor = gradientColor * fragColor.a;\n";
114const char* gFS_Main_BitmapShader_Modulate =
115        "    fragColor = bitmapColor * fragColor.a;\n";
116const char* gFS_Main_FragColor =
117        "    gl_FragColor = fragColor;\n";
118const char* gFS_Main_ApplyColorOp[4] = {
119        // None
120        "",
121        // Matrix
122        // TODO: Fix premultiplied alpha computations for color matrix
123        "    fragColor *= colorMatrix;\n"
124        "    fragColor += colorMatrixVector;\n"
125        "    fragColor.rgb *= fragColor.a;\n",
126        // Lighting
127        "    float lightingAlpha = fragColor.a;\n"
128        "    fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
129        "    fragColor.a = lightingAlpha;\n",
130        // PorterDuff
131        "    fragColor = blendColors(colorBlend, fragColor);\n"
132};
133const char* gFS_Footer =
134        "}\n\n";
135
136///////////////////////////////////////////////////////////////////////////////
137// PorterDuff snippets
138///////////////////////////////////////////////////////////////////////////////
139
140const char* gPorterDuff[12] = {
141        // Clear
142        "return vec4(0.0, 0.0, 0.0, 0.0);\n",
143        // Src
144        "return src;\n",
145        // Dst
146        "return dst;\n",
147        // SrcOver
148        "return src + dst * (1.0 - src.a);\n",
149        // DstOver
150        "return dst + src * (1.0 - dst.a);\n",
151        // SrcIn
152        "return src * dst.a;\n",
153        // DstIn
154        "return dst * src.a;\n",
155        // SrcOut
156        "return src * (1.0 - dst.a);\n",
157        // DstOut
158        "return dst * (1.0 - src.a);\n",
159        // SrcAtop
160        "return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
161        // DstAtop
162        "return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
163        // Xor
164        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, 1.0, "
165                "src.a + dst.a - 2.0 * src.a * dst.a);\n",
166};
167
168///////////////////////////////////////////////////////////////////////////////
169// Constructors/destructors
170///////////////////////////////////////////////////////////////////////////////
171
172ProgramCache::ProgramCache() {
173}
174
175ProgramCache::~ProgramCache() {
176    clear();
177}
178
179///////////////////////////////////////////////////////////////////////////////
180// Cache management
181///////////////////////////////////////////////////////////////////////////////
182
183void ProgramCache::clear() {
184    size_t count = mCache.size();
185    for (size_t i = 0; i < count; i++) {
186        delete mCache.valueAt(i);
187    }
188    mCache.clear();
189}
190
191Program* ProgramCache::get(const ProgramDescription& description) {
192    programid key = description.key();
193    ssize_t index = mCache.indexOfKey(key);
194    Program* program = NULL;
195    if (index < 0) {
196        PROGRAM_LOGD("Could not find program with key 0x%x", key);
197        program = generateProgram(description, key);
198        mCache.add(key, program);
199    } else {
200        program = mCache.valueAt(index);
201    }
202    return program;
203}
204
205///////////////////////////////////////////////////////////////////////////////
206// Program generation
207///////////////////////////////////////////////////////////////////////////////
208
209Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
210    String8 vertexShader = generateVertexShader(description);
211    String8 fragmentShader = generateFragmentShader(description);
212
213    Program* program = new Program(vertexShader.string(), fragmentShader.string());
214    return program;
215}
216
217String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
218    // Add attributes
219    String8 shader(gVS_Header_Attributes);
220    if (description.hasTexture) {
221        shader.append(gVS_Header_Attributes_TexCoords);
222    }
223    // Uniforms
224    shader.append(gVS_Header_Uniforms);
225    if (description.hasGradient) {
226        shader.append(gVS_Header_Uniforms_HasGradient);
227    }
228    if (description.hasBitmap) {
229        shader.append(gVS_Header_Uniforms_HasBitmap);
230    }
231    // Varyings
232    if (description.hasTexture) {
233        shader.append(gVS_Header_Varyings_HasTexture);
234    }
235    if (description.hasGradient) {
236        shader.append(gVS_Header_Varyings_HasGradient);
237    }
238    if (description.hasBitmap) {
239        shader.append(gVS_Header_Varyings_HasBitmap);
240    }
241
242    // Begin the shader
243    shader.append(gVS_Main); {
244        if (description.hasTexture) {
245            shader.append(gVS_Main_OutTexCoords);
246        }
247        if (description.hasGradient) {
248            shader.append(gVS_Main_OutGradientIndex);
249        }
250        if (description.hasBitmap) {
251            shader.append(gVS_Main_OutBitmapTexCoords);
252        }
253        // Output transformed position
254        shader.append(gVS_Main_Position);
255    }
256    // End the shader
257    shader.append(gVS_Footer);
258
259    PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());
260
261    return shader;
262}
263
264String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
265    // Set the default precision
266    String8 shader(gFS_Header);
267
268    // Varyings
269    if (description.hasTexture) {
270        shader.append(gVS_Header_Varyings_HasTexture);
271    }
272    if (description.hasGradient) {
273        shader.append(gVS_Header_Varyings_HasGradient);
274    }
275    if (description.hasBitmap) {
276        shader.append(gVS_Header_Varyings_HasBitmap);
277    }
278
279
280    // Uniforms
281    shader.append(gFS_Uniforms_Color);
282    if (description.hasTexture) {
283        shader.append(gFS_Uniforms_TextureSampler);
284    }
285    if (description.hasGradient) {
286        shader.append(gFS_Uniforms_GradientSampler);
287    }
288    if (description.hasBitmap) {
289        shader.append(gFS_Uniforms_BitmapSampler);
290    }
291    shader.append(gFS_Uniforms_ColorOp[description.colorOp]);
292
293    // Generate required functions
294    if (description.hasGradient && description.hasBitmap) {
295        generatePorterDuffBlend(shader, "blendShaders", description.shadersMode);
296    }
297    if (description.colorOp == ProgramDescription::kColorBlend) {
298        generatePorterDuffBlend(shader, "blendColors", description.colorMode);
299    }
300    if (description.isBitmapNpot) {
301        generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
302    }
303
304    // Begin the shader
305    shader.append(gFS_Main); {
306        // Stores the result in fragColor directly
307        if (description.hasTexture) {
308            if (description.hasAlpha8Texture) {
309                shader.append(gFS_Main_FetchA8Texture);
310            } else {
311                shader.append(gFS_Main_FetchTexture);
312            }
313        } else {
314            shader.append(gFS_Main_FetchColor);
315        }
316        if (description.hasGradient) {
317            shader.append(gFS_Main_FetchGradient);
318        }
319        if (description.hasBitmap) {
320            if (!description.isBitmapNpot) {
321                shader.append(gFS_Main_FetchBitmap);
322            } else {
323                shader.append(gFS_Main_FetchBitmapNpot);
324            }
325        }
326        // Case when we have two shaders set
327        if (description.hasGradient && description.hasBitmap) {
328            if (description.isBitmapFirst) {
329                shader.append(gFS_Main_BlendShadersBG);
330            } else {
331                shader.append(gFS_Main_BlendShadersGB);
332            }
333            shader.append(gFS_Main_BlendShaders_Modulate);
334        } else {
335            if (description.hasGradient) {
336                shader.append(gFS_Main_GradientShader_Modulate);
337            } else if (description.hasBitmap) {
338                shader.append(gFS_Main_BitmapShader_Modulate);
339            }
340        }
341        // Apply the color op if needed
342        shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
343        // Output the fragment
344        shader.append(gFS_Main_FragColor);
345    }
346    // End the shader
347    shader.append(gFS_Footer);
348
349    if (DEBUG_PROGRAM_CACHE) {
350        PROGRAM_LOGD("*** Generated fragment shader:\n\n");
351        printLongString(shader);
352    }
353
354    return shader;
355}
356
357void ProgramCache::generatePorterDuffBlend(String8& shader, const char* name,
358        SkXfermode::Mode mode) {
359    shader.append("\nvec4 ");
360    shader.append(name);
361    shader.append("(vec4 src, vec4 dst) {\n");
362    shader.append("    ");
363    shader.append(gPorterDuff[mode]);
364    shader.append("}\n");
365}
366
367void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
368    shader.append("\nvec2 wrap(vec2 texCoords) {\n");
369    if (wrapS == GL_MIRRORED_REPEAT) {
370        shader.append("    float xMod2 = mod(texCoords.x, 2.0);\n");
371        shader.append("    if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
372    }
373    if (wrapT == GL_MIRRORED_REPEAT) {
374        shader.append("    float yMod2 = mod(texCoords.y, 2.0);\n");
375        shader.append("    if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
376    }
377    shader.append("    return vec2(");
378    switch (wrapS) {
379        case GL_REPEAT:
380            shader.append("mod(texCoords.x, 1.0)");
381            break;
382        case GL_MIRRORED_REPEAT:
383            shader.append("xMod2");
384            break;
385    }
386    shader.append(", ");
387    switch (wrapT) {
388        case GL_REPEAT:
389            shader.append("mod(texCoords.y, 1.0)");
390            break;
391        case GL_MIRRORED_REPEAT:
392            shader.append("yMod2");
393            break;
394    }
395    shader.append(");\n");
396    shader.append("}\n");
397}
398
399void ProgramCache::printLongString(const String8& shader) const {
400    ssize_t index = 0;
401    ssize_t lastIndex = 0;
402    const char* str = shader.string();
403    while ((index = shader.find("\n", index)) > -1) {
404        String8 line(str, index - lastIndex);
405        if (line.length() == 0) line.append("\n");
406        PROGRAM_LOGD("%s", line.string());
407        index++;
408        str += (index - lastIndex);
409        lastIndex = index;
410    }
411}
412
413}; // namespace uirenderer
414}; // namespace android
415