ProgramCache.cpp revision 14830948d02f768c41b97b7a8d15e1b3cab78267 
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[3] = {
37        // Linear
38        "uniform mat4 screenSpace;\n",
39        // Circular
40        "uniform mat4 screenSpace;\n",
41        // Sweep
42        "uniform mat4 screenSpace;\n"
43};
44const char* gVS_Header_Uniforms_HasBitmap =
45        "uniform mat4 textureTransform;\n"
46        "uniform vec2 textureDimension;\n";
47const char* gVS_Header_Varyings_HasTexture =
48        "varying vec2 outTexCoords;\n";
49const char* gVS_Header_Varyings_HasBitmap =
50        "varying vec2 outBitmapTexCoords;\n";
51const char* gVS_Header_Varyings_HasGradient[3] = {
52        // Linear
53        "varying float index;\n",
54        // Circular
55        "varying vec2 circular;\n",
56        // Sweep
57        "varying vec2 sweep;\n"
58};
59const char* gVS_Main =
60        "\nvoid main(void) {\n";
61const char* gVS_Main_OutTexCoords =
62        "    outTexCoords = texCoords;\n";
63const char* gVS_Main_OutGradient[3] = {
64        // Linear
65        "    index = (screenSpace * position).x;\n",
66        // Circular
67        "    circular = (screenSpace * position).xy;\n",
68        // Sweep
69        "    sweep = (screenSpace * position).xy;\n"
70};
71const char* gVS_Main_OutBitmapTexCoords =
72        "    vec4 bitmapCoords = textureTransform * position;\n"
73        "    outBitmapTexCoords = bitmapCoords.xy * textureDimension;\n";
74const char* gVS_Main_Position =
75        "    gl_Position = transform * position;\n";
76const char* gVS_Footer =
77        "}\n\n";
78
79///////////////////////////////////////////////////////////////////////////////
80// Fragment shaders snippets
81///////////////////////////////////////////////////////////////////////////////
82
83const char* gFS_Header_Extension_FramebufferFetch =
84        "#extension GL_NV_shader_framebuffer_fetch : enable\n\n";
85const char* gFS_Header =
86        "precision mediump float;\n\n";
87const char* gFS_Uniforms_Color =
88        "uniform vec4 color;\n";
89const char* gFS_Uniforms_TextureSampler =
90        "uniform sampler2D sampler;\n";
91const char* gFS_Uniforms_GradientSampler[3] = {
92        // Linear
93        "uniform sampler2D gradientSampler;\n",
94        // Circular
95        "uniform sampler2D gradientSampler;\n",
96        // Sweep
97        "uniform sampler2D gradientSampler;\n"
98};
99const char* gFS_Uniforms_BitmapSampler =
100        "uniform sampler2D bitmapSampler;\n";
101const char* gFS_Uniforms_ColorOp[4] = {
102        // None
103        "",
104        // Matrix
105        "uniform mat4 colorMatrix;\n"
106        "uniform vec4 colorMatrixVector;\n",
107        // Lighting
108        "uniform vec4 lightingMul;\n"
109        "uniform vec4 lightingAdd;\n",
110        // PorterDuff
111        "uniform vec4 colorBlend;\n"
112};
113const char* gFS_Main =
114        "\nvoid main(void) {\n"
115        "    lowp vec4 fragColor;\n";
116const char* gFS_Main_FetchColor =
117        "    fragColor = color;\n";
118const char* gFS_Main_FetchTexture =
119        "    fragColor = color * texture2D(sampler, outTexCoords);\n";
120const char* gFS_Main_FetchA8Texture =
121        "    fragColor = color * texture2D(sampler, outTexCoords).a;\n";
122const char* gFS_Main_FetchGradient[3] = {
123        // Linear
124        "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
125        // Circular
126        "    float index = length(circular);\n"
127        "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
128        // Sweep
129        "    float index = atan(sweep.y, sweep.x) * 0.15915494309; // inv(2 * PI)\n"
130        "    vec4 gradientColor = texture2D(gradientSampler, vec2(index - floor(index), 0.5));\n"
131};
132const char* gFS_Main_FetchBitmap =
133        "    vec4 bitmapColor = texture2D(bitmapSampler, outBitmapTexCoords);\n";
134const char* gFS_Main_FetchBitmapNpot =
135        "    vec4 bitmapColor = texture2D(bitmapSampler, wrap(outBitmapTexCoords));\n";
136const char* gFS_Main_BlendShadersBG =
137        "    fragColor = blendShaders(gradientColor, bitmapColor)";
138const char* gFS_Main_BlendShadersGB =
139        "    fragColor = blendShaders(bitmapColor, gradientColor)";
140const char* gFS_Main_BlendShaders_Modulate =
141        " * fragColor.a;\n";
142const char* gFS_Main_GradientShader_Modulate =
143        "    fragColor = gradientColor * fragColor.a;\n";
144const char* gFS_Main_BitmapShader_Modulate =
145        "    fragColor = bitmapColor * fragColor.a;\n";
146const char* gFS_Main_FragColor =
147        "    gl_FragColor = fragColor;\n";
148const char* gFS_Main_FragColor_Blend =
149        "    gl_FragColor = blendFramebuffer(fragColor, gl_LastFragColor);\n";
150const char* gFS_Main_FragColor_Blend_Swap =
151        "    gl_FragColor = blendFramebuffer(gl_LastFragColor, fragColor);\n";
152const char* gFS_Main_ApplyColorOp[4] = {
153        // None
154        "",
155        // Matrix
156        // TODO: Fix premultiplied alpha computations for color matrix
157        "    fragColor *= colorMatrix;\n"
158        "    fragColor += colorMatrixVector;\n"
159        "    fragColor.rgb *= fragColor.a;\n",
160        // Lighting
161        "    float lightingAlpha = fragColor.a;\n"
162        "    fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
163        "    fragColor.a = lightingAlpha;\n",
164        // PorterDuff
165        "    fragColor = blendColors(colorBlend, fragColor);\n"
166};
167const char* gFS_Footer =
168        "}\n\n";
169
170///////////////////////////////////////////////////////////////////////////////
171// PorterDuff snippets
172///////////////////////////////////////////////////////////////////////////////
173
174const char* gBlendOps[18] = {
175        // Clear
176        "return vec4(0.0, 0.0, 0.0, 0.0);\n",
177        // Src
178        "return src;\n",
179        // Dst
180        "return dst;\n",
181        // SrcOver
182        "return src + dst * (1.0 - src.a);\n",
183        // DstOver
184        "return dst + src * (1.0 - dst.a);\n",
185        // SrcIn
186        "return src * dst.a;\n",
187        // DstIn
188        "return dst * src.a;\n",
189        // SrcOut
190        "return src * (1.0 - dst.a);\n",
191        // DstOut
192        "return dst * (1.0 - src.a);\n",
193        // SrcAtop
194        "return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
195        // DstAtop
196        "return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
197        // Xor
198        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, "
199                "src.a + dst.a - 2.0 * src.a * dst.a);\n",
200        // Add
201        "return min(src + dst, 1.0);\n",
202        // Multiply
203        "return src * dst;\n",
204        // Screen
205        "return src + dst - src * dst;\n",
206        // Overlay
207        "return clamp(vec4(mix("
208                "2.0 * src.rgb * dst.rgb + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
209                "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), "
210                "step(dst.a, 2.0 * dst.rgb)), "
211                "src.a + dst.a - src.a * dst.a), 0.0, 1.0);\n",
212        // Darken
213        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
214                "min(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
215        // Lighten
216        "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
217                "max(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
218};
219
220///////////////////////////////////////////////////////////////////////////////
221// Constructors/destructors
222///////////////////////////////////////////////////////////////////////////////
223
224ProgramCache::ProgramCache() {
225}
226
227ProgramCache::~ProgramCache() {
228    clear();
229}
230
231///////////////////////////////////////////////////////////////////////////////
232// Cache management
233///////////////////////////////////////////////////////////////////////////////
234
235void ProgramCache::clear() {
236    size_t count = mCache.size();
237    for (size_t i = 0; i < count; i++) {
238        delete mCache.valueAt(i);
239    }
240    mCache.clear();
241}
242
243Program* ProgramCache::get(const ProgramDescription& description) {
244    programid key = description.key();
245    ssize_t index = mCache.indexOfKey(key);
246    Program* program = NULL;
247    if (index < 0) {
248        description.log("Could not find program");
249        program = generateProgram(description, key);
250        mCache.add(key, program);
251    } else {
252        program = mCache.valueAt(index);
253    }
254    return program;
255}
256
257///////////////////////////////////////////////////////////////////////////////
258// Program generation
259///////////////////////////////////////////////////////////////////////////////
260
261Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
262    String8 vertexShader = generateVertexShader(description);
263    String8 fragmentShader = generateFragmentShader(description);
264
265    Program* program = new Program(vertexShader.string(), fragmentShader.string());
266    return program;
267}
268
269String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
270    // Add attributes
271    String8 shader(gVS_Header_Attributes);
272    if (description.hasTexture) {
273        shader.append(gVS_Header_Attributes_TexCoords);
274    }
275    // Uniforms
276    shader.append(gVS_Header_Uniforms);
277    if (description.hasGradient) {
278        shader.append(gVS_Header_Uniforms_HasGradient[description.gradientType]);
279    }
280    if (description.hasBitmap) {
281        shader.append(gVS_Header_Uniforms_HasBitmap);
282    }
283    // Varyings
284    if (description.hasTexture) {
285        shader.append(gVS_Header_Varyings_HasTexture);
286    }
287    if (description.hasGradient) {
288        shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
289    }
290    if (description.hasBitmap) {
291        shader.append(gVS_Header_Varyings_HasBitmap);
292    }
293
294    // Begin the shader
295    shader.append(gVS_Main); {
296        if (description.hasTexture) {
297            shader.append(gVS_Main_OutTexCoords);
298        }
299        if (description.hasGradient) {
300            shader.append(gVS_Main_OutGradient[description.gradientType]);
301        }
302        if (description.hasBitmap) {
303            shader.append(gVS_Main_OutBitmapTexCoords);
304        }
305        // Output transformed position
306        shader.append(gVS_Main_Position);
307    }
308    // End the shader
309    shader.append(gVS_Footer);
310
311    PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());
312
313    return shader;
314}
315
316String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
317    // Set the default precision
318    String8 shader;
319
320    bool blendFramebuffer = description.framebufferMode >= SkXfermode::kPlus_Mode;
321    if (blendFramebuffer) {
322        shader.append(gFS_Header_Extension_FramebufferFetch);
323    }
324
325    shader.append(gFS_Header);
326
327    // Varyings
328    if (description.hasTexture) {
329        shader.append(gVS_Header_Varyings_HasTexture);
330    }
331    if (description.hasGradient) {
332        shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
333    }
334    if (description.hasBitmap) {
335        shader.append(gVS_Header_Varyings_HasBitmap);
336    }
337
338
339    // Uniforms
340    shader.append(gFS_Uniforms_Color);
341    if (description.hasTexture) {
342        shader.append(gFS_Uniforms_TextureSampler);
343    }
344    if (description.hasGradient) {
345        shader.append(gFS_Uniforms_GradientSampler[description.gradientType]);
346    }
347    if (description.hasBitmap) {
348        shader.append(gFS_Uniforms_BitmapSampler);
349    }
350    shader.append(gFS_Uniforms_ColorOp[description.colorOp]);
351
352    // Generate required functions
353    if (description.hasGradient && description.hasBitmap) {
354        generateBlend(shader, "blendShaders", description.shadersMode);
355    }
356    if (description.colorOp == ProgramDescription::kColorBlend) {
357        generateBlend(shader, "blendColors", description.colorMode);
358    }
359    if (blendFramebuffer) {
360        generateBlend(shader, "blendFramebuffer", description.framebufferMode);
361    }
362    if (description.isBitmapNpot) {
363        generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
364    }
365
366    // Begin the shader
367    shader.append(gFS_Main); {
368        // Stores the result in fragColor directly
369        if (description.hasTexture) {
370            if (description.hasAlpha8Texture) {
371                shader.append(gFS_Main_FetchA8Texture);
372            } else {
373                shader.append(gFS_Main_FetchTexture);
374            }
375        } else {
376            shader.append(gFS_Main_FetchColor);
377        }
378        if (description.hasGradient) {
379            shader.append(gFS_Main_FetchGradient[description.gradientType]);
380        }
381        if (description.hasBitmap) {
382            if (!description.isBitmapNpot) {
383                shader.append(gFS_Main_FetchBitmap);
384            } else {
385                shader.append(gFS_Main_FetchBitmapNpot);
386            }
387        }
388        // Case when we have two shaders set
389        if (description.hasGradient && description.hasBitmap) {
390            if (description.isBitmapFirst) {
391                shader.append(gFS_Main_BlendShadersBG);
392            } else {
393                shader.append(gFS_Main_BlendShadersGB);
394            }
395            shader.append(gFS_Main_BlendShaders_Modulate);
396        } else {
397            if (description.hasGradient) {
398                shader.append(gFS_Main_GradientShader_Modulate);
399            } else if (description.hasBitmap) {
400                shader.append(gFS_Main_BitmapShader_Modulate);
401            }
402        }
403        // Apply the color op if needed
404        shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
405        // Output the fragment
406        if (!blendFramebuffer) {
407            shader.append(gFS_Main_FragColor);
408        } else {
409            shader.append(!description.swapSrcDst ?
410                    gFS_Main_FragColor_Blend : gFS_Main_FragColor_Blend_Swap);
411        }
412    }
413    // End the shader
414    shader.append(gFS_Footer);
415
416    if (DEBUG_PROGRAM_CACHE) {
417        PROGRAM_LOGD("*** Generated fragment shader:\n\n");
418        printLongString(shader);
419    }
420
421    return shader;
422}
423
424void ProgramCache::generateBlend(String8& shader, const char* name, SkXfermode::Mode mode) {
425    shader.append("\nvec4 ");
426    shader.append(name);
427    shader.append("(vec4 src, vec4 dst) {\n");
428    shader.append("    ");
429    shader.append(gBlendOps[mode]);
430    shader.append("}\n");
431}
432
433void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
434    shader.append("\nvec2 wrap(vec2 texCoords) {\n");
435    if (wrapS == GL_MIRRORED_REPEAT) {
436        shader.append("    float xMod2 = mod(texCoords.x, 2.0);\n");
437        shader.append("    if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
438    }
439    if (wrapT == GL_MIRRORED_REPEAT) {
440        shader.append("    float yMod2 = mod(texCoords.y, 2.0);\n");
441        shader.append("    if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
442    }
443    shader.append("    return vec2(");
444    switch (wrapS) {
445        case GL_CLAMP_TO_EDGE:
446            shader.append("texCoords.x");
447            break;
448        case GL_REPEAT:
449            shader.append("mod(texCoords.x, 1.0)");
450            break;
451        case GL_MIRRORED_REPEAT:
452            shader.append("xMod2");
453            break;
454    }
455    shader.append(", ");
456    switch (wrapT) {
457        case GL_CLAMP_TO_EDGE:
458            shader.append("texCoords.y");
459            break;
460        case GL_REPEAT:
461            shader.append("mod(texCoords.y, 1.0)");
462            break;
463        case GL_MIRRORED_REPEAT:
464            shader.append("yMod2");
465            break;
466    }
467    shader.append(");\n");
468    shader.append("}\n");
469}
470
471void ProgramCache::printLongString(const String8& shader) const {
472    ssize_t index = 0;
473    ssize_t lastIndex = 0;
474    const char* str = shader.string();
475    while ((index = shader.find("\n", index)) > -1) {
476        String8 line(str, index - lastIndex);
477        if (line.length() == 0) line.append("\n");
478        PROGRAM_LOGD("%s", line.string());
479        index++;
480        str += (index - lastIndex);
481        lastIndex = index;
482    }
483}
484
485}; // namespace uirenderer
486}; // namespace android
487