ProgramCache.cpp revision f607bdc167f66b3e7003acaa4736ae46d78c1492 
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_Extension_FramebufferFetch =
70        "#extension GL_NV_shader_framebuffer_fetch : enable\n\n";
71const char* gFS_Header =
72        "precision mediump float;\n\n";
73const char* gFS_Uniforms_Color =
74        "uniform vec4 color;\n";
75const char* gFS_Uniforms_TextureSampler =
76        "uniform sampler2D sampler;\n";
77const char* gFS_Uniforms_GradientSampler =
78        "uniform sampler2D gradientSampler;\n";
79const char* gFS_Uniforms_BitmapSampler =
80        "uniform sampler2D bitmapSampler;\n";
81const char* gFS_Uniforms_ColorOp[4] = {
82        // None
83        "",
84        // Matrix
85        "uniform mat4 colorMatrix;\n"
86        "uniform vec4 colorMatrixVector;\n",
87        // Lighting
88        "uniform vec4 lightingMul;\n"
89        "uniform vec4 lightingAdd;\n",
90        // PorterDuff
91        "uniform vec4 colorBlend;\n"
92};
93const char* gFS_Main =
94        "\nvoid main(void) {\n"
95        "    lowp vec4 fragColor;\n";
96const char* gFS_Main_FetchColor =
97        "    fragColor = color;\n";
98const char* gFS_Main_FetchTexture =
99        "    fragColor = color * texture2D(sampler, outTexCoords);\n";
100const char* gFS_Main_FetchA8Texture =
101        "    fragColor = color * texture2D(sampler, outTexCoords).a;\n";
102const char* gFS_Main_FetchGradient =
103        "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n";
104const char* gFS_Main_FetchBitmap =
105        "    vec4 bitmapColor = texture2D(bitmapSampler, outBitmapTexCoords);\n";
106const char* gFS_Main_FetchBitmapNpot =
107        "    vec4 bitmapColor = texture2D(bitmapSampler, wrap(outBitmapTexCoords));\n";
108const char* gFS_Main_BlendShadersBG =
109        "    fragColor = blendShaders(gradientColor, bitmapColor)";
110const char* gFS_Main_BlendShadersGB =
111        "    fragColor = blendShaders(bitmapColor, gradientColor)";
112const char* gFS_Main_BlendShaders_Modulate =
113        " * fragColor.a;\n";
114const char* gFS_Main_GradientShader_Modulate =
115        "    fragColor = gradientColor * fragColor.a;\n";
116const char* gFS_Main_BitmapShader_Modulate =
117        "    fragColor = bitmapColor * fragColor.a;\n";
118const char* gFS_Main_FragColor =
119        "    gl_FragColor = fragColor;\n";
120const char* gFS_Main_FragColor_Blend =
121        "    gl_FragColor = blendFramebuffer(fragColor, gl_LastFragColor);\n";
122const char* gFS_Main_FragColor_Blend_Swap =
123        "    gl_FragColor = blendFramebuffer(gl_LastFragColor, fragColor);\n";
124const char* gFS_Main_ApplyColorOp[4] = {
125        // None
126        "",
127        // Matrix
128        // TODO: Fix premultiplied alpha computations for color matrix
129        "    fragColor *= colorMatrix;\n"
130        "    fragColor += colorMatrixVector;\n"
131        "    fragColor.rgb *= fragColor.a;\n",
132        // Lighting
133        "    float lightingAlpha = fragColor.a;\n"
134        "    fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
135        "    fragColor.a = lightingAlpha;\n",
136        // PorterDuff
137        "    fragColor = blendColors(colorBlend, fragColor);\n"
138};
139const char* gFS_Footer =
140        "}\n\n";
141
142///////////////////////////////////////////////////////////////////////////////
143// PorterDuff snippets
144///////////////////////////////////////////////////////////////////////////////
145
146const char* gBlendOps[18] = {
147        // Clear
148        "return vec4(0.0, 0.0, 0.0, 0.0);\n",
149        // Src
150        "return src;\n",
151        // Dst
152        "return dst;\n",
153        // SrcOver
154        "return src + dst * (1.0 - src.a);\n",
155        // DstOver
156        "return dst + src * (1.0 - dst.a);\n",
157        // SrcIn
158        "return src * dst.a;\n",
159        // DstIn
160        "return dst * src.a;\n",
161        // SrcOut
162        "return src * (1.0 - dst.a);\n",
163        // DstOut
164        "return dst * (1.0 - src.a);\n",
165        // SrcAtop
166        "return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
167        // DstAtop
168        "return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
169        // Xor
170        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, "
171                "src.a + dst.a - 2.0 * src.a * dst.a);\n",
172        // Add
173        "return min(src + dst, 1.0);\n",
174        // Multiply
175        "return src * dst;\n",
176        // Screen
177        "return src + dst - src * dst;\n",
178        // Overlay
179        "return clamp(vec4(mix("
180                "2.0 * src.rgb * dst.rgb + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
181                "src.a * dst.a - 2.0 * (dst.a - dst.rgb) * (src.a - src.rgb) + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
182                "step(dst.a, 2.0 * dst.rgb)), "
183                "src.a + dst.a - src.a * dst.a), 0.0, 1.0);\n",
184        // Darken
185        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
186                "min(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
187        // Lighten
188        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
189                "max(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
190};
191
192///////////////////////////////////////////////////////////////////////////////
193// Constructors/destructors
194///////////////////////////////////////////////////////////////////////////////
195
196ProgramCache::ProgramCache() {
197}
198
199ProgramCache::~ProgramCache() {
200    clear();
201}
202
203///////////////////////////////////////////////////////////////////////////////
204// Cache management
205///////////////////////////////////////////////////////////////////////////////
206
207void ProgramCache::clear() {
208    size_t count = mCache.size();
209    for (size_t i = 0; i < count; i++) {
210        delete mCache.valueAt(i);
211    }
212    mCache.clear();
213}
214
215Program* ProgramCache::get(const ProgramDescription& description) {
216    programid key = description.key();
217    ssize_t index = mCache.indexOfKey(key);
218    Program* program = NULL;
219    if (index < 0) {
220        PROGRAM_LOGD("Could not find program with key 0x%x", key);
221        program = generateProgram(description, key);
222        mCache.add(key, program);
223    } else {
224        program = mCache.valueAt(index);
225    }
226    return program;
227}
228
229///////////////////////////////////////////////////////////////////////////////
230// Program generation
231///////////////////////////////////////////////////////////////////////////////
232
233Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
234    String8 vertexShader = generateVertexShader(description);
235    String8 fragmentShader = generateFragmentShader(description);
236
237    Program* program = new Program(vertexShader.string(), fragmentShader.string());
238    return program;
239}
240
241String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
242    // Add attributes
243    String8 shader(gVS_Header_Attributes);
244    if (description.hasTexture) {
245        shader.append(gVS_Header_Attributes_TexCoords);
246    }
247    // Uniforms
248    shader.append(gVS_Header_Uniforms);
249    if (description.hasGradient) {
250        shader.append(gVS_Header_Uniforms_HasGradient);
251    }
252    if (description.hasBitmap) {
253        shader.append(gVS_Header_Uniforms_HasBitmap);
254    }
255    // Varyings
256    if (description.hasTexture) {
257        shader.append(gVS_Header_Varyings_HasTexture);
258    }
259    if (description.hasGradient) {
260        shader.append(gVS_Header_Varyings_HasGradient);
261    }
262    if (description.hasBitmap) {
263        shader.append(gVS_Header_Varyings_HasBitmap);
264    }
265
266    // Begin the shader
267    shader.append(gVS_Main); {
268        if (description.hasTexture) {
269            shader.append(gVS_Main_OutTexCoords);
270        }
271        if (description.hasGradient) {
272            shader.append(gVS_Main_OutGradientIndex);
273        }
274        if (description.hasBitmap) {
275            shader.append(gVS_Main_OutBitmapTexCoords);
276        }
277        // Output transformed position
278        shader.append(gVS_Main_Position);
279    }
280    // End the shader
281    shader.append(gVS_Footer);
282
283    PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());
284
285    return shader;
286}
287
288String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
289    // Set the default precision
290    String8 shader;
291
292    bool blendFramebuffer = description.framebufferMode >= SkXfermode::kPlus_Mode;
293    if (blendFramebuffer) {
294        shader.append(gFS_Header_Extension_FramebufferFetch);
295    }
296
297    shader.append(gFS_Header);
298
299    // Varyings
300    if (description.hasTexture) {
301        shader.append(gVS_Header_Varyings_HasTexture);
302    }
303    if (description.hasGradient) {
304        shader.append(gVS_Header_Varyings_HasGradient);
305    }
306    if (description.hasBitmap) {
307        shader.append(gVS_Header_Varyings_HasBitmap);
308    }
309
310
311    // Uniforms
312    shader.append(gFS_Uniforms_Color);
313    if (description.hasTexture) {
314        shader.append(gFS_Uniforms_TextureSampler);
315    }
316    if (description.hasGradient) {
317        shader.append(gFS_Uniforms_GradientSampler);
318    }
319    if (description.hasBitmap) {
320        shader.append(gFS_Uniforms_BitmapSampler);
321    }
322    shader.append(gFS_Uniforms_ColorOp[description.colorOp]);
323
324    // Generate required functions
325    if (description.hasGradient && description.hasBitmap) {
326        generateBlend(shader, "blendShaders", description.shadersMode);
327    }
328    if (description.colorOp == ProgramDescription::kColorBlend) {
329        generateBlend(shader, "blendColors", description.colorMode);
330    }
331    if (blendFramebuffer) {
332        generateBlend(shader, "blendFramebuffer", description.framebufferMode);
333    }
334    if (description.isBitmapNpot) {
335        generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
336    }
337
338    // Begin the shader
339    shader.append(gFS_Main); {
340        // Stores the result in fragColor directly
341        if (description.hasTexture) {
342            if (description.hasAlpha8Texture) {
343                shader.append(gFS_Main_FetchA8Texture);
344            } else {
345                shader.append(gFS_Main_FetchTexture);
346            }
347        } else {
348            shader.append(gFS_Main_FetchColor);
349        }
350        if (description.hasGradient) {
351            shader.append(gFS_Main_FetchGradient);
352        }
353        if (description.hasBitmap) {
354            if (!description.isBitmapNpot) {
355                shader.append(gFS_Main_FetchBitmap);
356            } else {
357                shader.append(gFS_Main_FetchBitmapNpot);
358            }
359        }
360        // Case when we have two shaders set
361        if (description.hasGradient && description.hasBitmap) {
362            if (description.isBitmapFirst) {
363                shader.append(gFS_Main_BlendShadersBG);
364            } else {
365                shader.append(gFS_Main_BlendShadersGB);
366            }
367            shader.append(gFS_Main_BlendShaders_Modulate);
368        } else {
369            if (description.hasGradient) {
370                shader.append(gFS_Main_GradientShader_Modulate);
371            } else if (description.hasBitmap) {
372                shader.append(gFS_Main_BitmapShader_Modulate);
373            }
374        }
375        // Apply the color op if needed
376        shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
377        // Output the fragment
378        if (!blendFramebuffer) {
379            shader.append(gFS_Main_FragColor);
380        } else {
381            shader.append(!description.swapSrcDst ?
382                    gFS_Main_FragColor_Blend : gFS_Main_FragColor_Blend_Swap);
383        }
384    }
385    // End the shader
386    shader.append(gFS_Footer);
387
388    if (DEBUG_PROGRAM_CACHE) {
389        PROGRAM_LOGD("*** Generated fragment shader:\n\n");
390        printLongString(shader);
391    }
392
393    return shader;
394}
395
396void ProgramCache::generateBlend(String8& shader, const char* name, SkXfermode::Mode mode) {
397    shader.append("\nvec4 ");
398    shader.append(name);
399    shader.append("(vec4 src, vec4 dst) {\n");
400    shader.append("    ");
401    shader.append(gBlendOps[mode]);
402    shader.append("}\n");
403}
404
405void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
406    shader.append("\nvec2 wrap(vec2 texCoords) {\n");
407    if (wrapS == GL_MIRRORED_REPEAT) {
408        shader.append("    float xMod2 = mod(texCoords.x, 2.0);\n");
409        shader.append("    if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
410    }
411    if (wrapT == GL_MIRRORED_REPEAT) {
412        shader.append("    float yMod2 = mod(texCoords.y, 2.0);\n");
413        shader.append("    if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
414    }
415    shader.append("    return vec2(");
416    switch (wrapS) {
417        case GL_CLAMP_TO_EDGE:
418            shader.append("texCoords.x");
419            break;
420        case GL_REPEAT:
421            shader.append("mod(texCoords.x, 1.0)");
422            break;
423        case GL_MIRRORED_REPEAT:
424            shader.append("xMod2");
425            break;
426    }
427    shader.append(", ");
428    switch (wrapT) {
429        case GL_CLAMP_TO_EDGE:
430            shader.append("texCoords.y");
431            break;
432        case GL_REPEAT:
433            shader.append("mod(texCoords.y, 1.0)");
434            break;
435        case GL_MIRRORED_REPEAT:
436            shader.append("yMod2");
437            break;
438    }
439    shader.append(");\n");
440    shader.append("}\n");
441}
442
443void ProgramCache::printLongString(const String8& shader) const {
444    ssize_t index = 0;
445    ssize_t lastIndex = 0;
446    const char* str = shader.string();
447    while ((index = shader.find("\n", index)) > -1) {
448        String8 line(str, index - lastIndex);
449        if (line.length() == 0) line.append("\n");
450        PROGRAM_LOGD("%s", line.string());
451        index++;
452        str += (index - lastIndex);
453        lastIndex = index;
454    }
455}
456
457}; // namespace uirenderer
458}; // namespace android
459