ProgramCache.cpp revision a5aed0d58962a24c44728ffc46dc9e1ba2f9fda5 
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_ApplyColorOp[4] = {
123        // None
124        "",
125        // Matrix
126        // TODO: Fix premultiplied alpha computations for color matrix
127        "    fragColor *= colorMatrix;\n"
128        "    fragColor += colorMatrixVector;\n"
129        "    fragColor.rgb *= fragColor.a;\n",
130        // Lighting
131        "    float lightingAlpha = fragColor.a;\n"
132        "    fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
133        "    fragColor.a = lightingAlpha;\n",
134        // PorterDuff
135        "    fragColor = blendColors(colorBlend, fragColor);\n"
136};
137const char* gFS_Footer =
138        "}\n\n";
139
140///////////////////////////////////////////////////////////////////////////////
141// PorterDuff snippets
142///////////////////////////////////////////////////////////////////////////////
143
144const char* gBlendOps[18] = {
145        // Clear
146        "return vec4(0.0, 0.0, 0.0, 0.0);\n",
147        // Src
148        "return src;\n",
149        // Dst
150        "return dst;\n",
151        // SrcOver
152        "return src + dst * (1.0 - src.a);\n",
153        // DstOver
154        "return dst + src * (1.0 - dst.a);\n",
155        // SrcIn
156        "return src * dst.a;\n",
157        // DstIn
158        "return dst * src.a;\n",
159        // SrcOut
160        "return src * (1.0 - dst.a);\n",
161        // DstOut
162        "return dst * (1.0 - src.a);\n",
163        // SrcAtop
164        "return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
165        // DstAtop
166        "return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
167        // Xor
168        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, "
169                "src.a + dst.a - 2.0 * src.a * dst.a);\n",
170        // Add
171        "return min(src + dst, 1.0);\n",
172        // Multiply
173        "return src * dst;\n",
174        // Screen
175        "return src + dst - src * dst;\n",
176        // Overlay
177        "return clamp(vec4(mix("
178                "2.0 * src.rgb * dst.rgb + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
179                "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), "
180                "step(dst.a, 2.0 * dst.rgb)), "
181                "src.a + dst.a - src.a * dst.a), 0.0, 1.0);\n",
182        // Darken
183        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
184                "min(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
185        // Lighten
186        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
187                "max(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
188};
189
190///////////////////////////////////////////////////////////////////////////////
191// Constructors/destructors
192///////////////////////////////////////////////////////////////////////////////
193
194ProgramCache::ProgramCache() {
195}
196
197ProgramCache::~ProgramCache() {
198    clear();
199}
200
201///////////////////////////////////////////////////////////////////////////////
202// Cache management
203///////////////////////////////////////////////////////////////////////////////
204
205void ProgramCache::clear() {
206    size_t count = mCache.size();
207    for (size_t i = 0; i < count; i++) {
208        delete mCache.valueAt(i);
209    }
210    mCache.clear();
211}
212
213Program* ProgramCache::get(const ProgramDescription& description) {
214    programid key = description.key();
215    ssize_t index = mCache.indexOfKey(key);
216    Program* program = NULL;
217    if (index < 0) {
218        PROGRAM_LOGD("Could not find program with key 0x%x", key);
219        program = generateProgram(description, key);
220        mCache.add(key, program);
221    } else {
222        program = mCache.valueAt(index);
223    }
224    return program;
225}
226
227///////////////////////////////////////////////////////////////////////////////
228// Program generation
229///////////////////////////////////////////////////////////////////////////////
230
231Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
232    String8 vertexShader = generateVertexShader(description);
233    String8 fragmentShader = generateFragmentShader(description);
234
235    Program* program = new Program(vertexShader.string(), fragmentShader.string());
236    return program;
237}
238
239String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
240    // Add attributes
241    String8 shader(gVS_Header_Attributes);
242    if (description.hasTexture) {
243        shader.append(gVS_Header_Attributes_TexCoords);
244    }
245    // Uniforms
246    shader.append(gVS_Header_Uniforms);
247    if (description.hasGradient) {
248        shader.append(gVS_Header_Uniforms_HasGradient);
249    }
250    if (description.hasBitmap) {
251        shader.append(gVS_Header_Uniforms_HasBitmap);
252    }
253    // Varyings
254    if (description.hasTexture) {
255        shader.append(gVS_Header_Varyings_HasTexture);
256    }
257    if (description.hasGradient) {
258        shader.append(gVS_Header_Varyings_HasGradient);
259    }
260    if (description.hasBitmap) {
261        shader.append(gVS_Header_Varyings_HasBitmap);
262    }
263
264    // Begin the shader
265    shader.append(gVS_Main); {
266        if (description.hasTexture) {
267            shader.append(gVS_Main_OutTexCoords);
268        }
269        if (description.hasGradient) {
270            shader.append(gVS_Main_OutGradientIndex);
271        }
272        if (description.hasBitmap) {
273            shader.append(gVS_Main_OutBitmapTexCoords);
274        }
275        // Output transformed position
276        shader.append(gVS_Main_Position);
277    }
278    // End the shader
279    shader.append(gVS_Footer);
280
281    PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());
282
283    return shader;
284}
285
286String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
287    // Set the default precision
288    String8 shader;
289
290    bool blendFramebuffer = description.framebufferMode >= SkXfermode::kPlus_Mode;
291    if (blendFramebuffer) {
292        shader.append(gFS_Header_Extension_FramebufferFetch);
293    }
294
295    shader.append(gFS_Header);
296
297    // Varyings
298    if (description.hasTexture) {
299        shader.append(gVS_Header_Varyings_HasTexture);
300    }
301    if (description.hasGradient) {
302        shader.append(gVS_Header_Varyings_HasGradient);
303    }
304    if (description.hasBitmap) {
305        shader.append(gVS_Header_Varyings_HasBitmap);
306    }
307
308
309    // Uniforms
310    shader.append(gFS_Uniforms_Color);
311    if (description.hasTexture) {
312        shader.append(gFS_Uniforms_TextureSampler);
313    }
314    if (description.hasGradient) {
315        shader.append(gFS_Uniforms_GradientSampler);
316    }
317    if (description.hasBitmap) {
318        shader.append(gFS_Uniforms_BitmapSampler);
319    }
320    shader.append(gFS_Uniforms_ColorOp[description.colorOp]);
321
322    // Generate required functions
323    if (description.hasGradient && description.hasBitmap) {
324        generateBlend(shader, "blendShaders", description.shadersMode);
325    }
326    if (description.colorOp == ProgramDescription::kColorBlend) {
327        generateBlend(shader, "blendColors", description.colorMode);
328    }
329    if (blendFramebuffer) {
330        generateBlend(shader, "blendFramebuffer", description.framebufferMode);
331    }
332    if (description.isBitmapNpot) {
333        generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
334    }
335
336    // Begin the shader
337    shader.append(gFS_Main); {
338        // Stores the result in fragColor directly
339        if (description.hasTexture) {
340            if (description.hasAlpha8Texture) {
341                shader.append(gFS_Main_FetchA8Texture);
342            } else {
343                shader.append(gFS_Main_FetchTexture);
344            }
345        } else {
346            shader.append(gFS_Main_FetchColor);
347        }
348        if (description.hasGradient) {
349            shader.append(gFS_Main_FetchGradient);
350        }
351        if (description.hasBitmap) {
352            if (!description.isBitmapNpot) {
353                shader.append(gFS_Main_FetchBitmap);
354            } else {
355                shader.append(gFS_Main_FetchBitmapNpot);
356            }
357        }
358        // Case when we have two shaders set
359        if (description.hasGradient && description.hasBitmap) {
360            if (description.isBitmapFirst) {
361                shader.append(gFS_Main_BlendShadersBG);
362            } else {
363                shader.append(gFS_Main_BlendShadersGB);
364            }
365            shader.append(gFS_Main_BlendShaders_Modulate);
366        } else {
367            if (description.hasGradient) {
368                shader.append(gFS_Main_GradientShader_Modulate);
369            } else if (description.hasBitmap) {
370                shader.append(gFS_Main_BitmapShader_Modulate);
371            }
372        }
373        // Apply the color op if needed
374        shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
375        // Output the fragment
376        if (!blendFramebuffer) {
377            shader.append(gFS_Main_FragColor);
378        } else {
379            shader.append(gFS_Main_FragColor_Blend);
380        }
381    }
382    // End the shader
383    shader.append(gFS_Footer);
384
385    if (DEBUG_PROGRAM_CACHE) {
386        PROGRAM_LOGD("*** Generated fragment shader:\n\n");
387        printLongString(shader);
388    }
389
390    return shader;
391}
392
393void ProgramCache::generateBlend(String8& shader, const char* name, SkXfermode::Mode mode) {
394    shader.append("\nvec4 ");
395    shader.append(name);
396    shader.append("(vec4 src, vec4 dst) {\n");
397    shader.append("    ");
398    shader.append(gBlendOps[mode]);
399    shader.append("}\n");
400}
401
402void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
403    shader.append("\nvec2 wrap(vec2 texCoords) {\n");
404    if (wrapS == GL_MIRRORED_REPEAT) {
405        shader.append("    float xMod2 = mod(texCoords.x, 2.0);\n");
406        shader.append("    if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
407    }
408    if (wrapT == GL_MIRRORED_REPEAT) {
409        shader.append("    float yMod2 = mod(texCoords.y, 2.0);\n");
410        shader.append("    if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
411    }
412    shader.append("    return vec2(");
413    switch (wrapS) {
414        case GL_CLAMP_TO_EDGE:
415            shader.append("texCoords.x");
416            break;
417        case GL_REPEAT:
418            shader.append("mod(texCoords.x, 1.0)");
419            break;
420        case GL_MIRRORED_REPEAT:
421            shader.append("xMod2");
422            break;
423    }
424    shader.append(", ");
425    switch (wrapT) {
426        case GL_CLAMP_TO_EDGE:
427            shader.append("texCoords.y");
428            break;
429        case GL_REPEAT:
430            shader.append("mod(texCoords.y, 1.0)");
431            break;
432        case GL_MIRRORED_REPEAT:
433            shader.append("yMod2");
434            break;
435    }
436    shader.append(");\n");
437    shader.append("}\n");
438}
439
440void ProgramCache::printLongString(const String8& shader) const {
441    ssize_t index = 0;
442    ssize_t lastIndex = 0;
443    const char* str = shader.string();
444    while ((index = shader.find("\n", index)) > -1) {
445        String8 line(str, index - lastIndex);
446        if (line.length() == 0) line.append("\n");
447        PROGRAM_LOGD("%s", line.string());
448        index++;
449        str += (index - lastIndex);
450        lastIndex = index;
451    }
452}
453
454}; // namespace uirenderer
455}; // namespace android
456