libs/hwui/ProgramCache.cpp - LeafOS-Project/android_frameworks_base - Gitiles

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "OpenGLRenderer"

 #include <utils/String8.h>

 #include "ProgramCache.h"

 namespace android {
 namespace uirenderer {

 ///////////////////////////////////////////////////////////////////////////////
 // Vertex shaders snippets
 ///////////////////////////////////////////////////////////////////////////////

 const char* gVS_Header_Attributes =
         "attribute vec4 position;\n";
 const char* gVS_Header_Attributes_TexCoords =
         "attribute vec2 texCoords;\n";
 const char* gVS_Header_Uniforms =
         "uniform mat4 transform;\n";
 const char* gVS_Header_Uniforms_HasGradient[3] = {
         // Linear
         "uniform float gradientLength;\n"
         "uniform vec2 gradient;\n"
         "uniform vec2 gradientStart;\n"
         "uniform mat4 screenSpace;\n",
         // Circular
         "uniform vec2 gradientStart;\n"
         "uniform mat4 gradientMatrix;\n"
         "uniform mat4 screenSpace;\n",
         // Sweep
         "uniform vec2 gradientStart;\n"
         "uniform mat4 gradientMatrix;\n"
         "uniform mat4 screenSpace;\n"
 };
 const char* gVS_Header_Uniforms_HasBitmap =
         "uniform mat4 textureTransform;\n"
         "uniform vec2 textureDimension;\n";
 const char* gVS_Header_Varyings_HasTexture =
         "varying vec2 outTexCoords;\n";
 const char* gVS_Header_Varyings_HasBitmap =
         "varying vec2 outBitmapTexCoords;\n";
 const char* gVS_Header_Varyings_HasGradient[3] = {
         // Linear
         "varying float index;\n",
         // Circular
         "varying vec2 circular;\n",
         // Sweep
         "varying vec2 sweep;\n"
 };
 const char* gVS_Main =
         "\nvoid main(void) {\n";
 const char* gVS_Main_OutTexCoords =
         "    outTexCoords = texCoords;\n";
 const char* gVS_Main_OutGradient[3] = {
         // Linear
         "    vec4 location = screenSpace * position;\n"
         "    index = dot(location.xy - gradientStart, gradient) * gradientLength;\n",
         // Circular
         "    vec4 location = screenSpace * position;\n"
         "    circular = (gradientMatrix * vec4(location.xy - gradientStart, 0.0, 0.0)).xy;\n",
         // Sweep
         "    vec4 location = screenSpace * position;\n"
         "    sweep = (gradientMatrix * vec4(location.xy - gradientStart, 0.0, 0.0)).xy;\n"
 };
 const char* gVS_Main_OutBitmapTexCoords =
         "    vec4 bitmapCoords = textureTransform * position;\n"
         "    outBitmapTexCoords = bitmapCoords.xy * textureDimension;\n";
 const char* gVS_Main_Position =
         "    gl_Position = transform * position;\n";
 const char* gVS_Footer =
         "}\n\n";

 ///////////////////////////////////////////////////////////////////////////////
 // Fragment shaders snippets
 ///////////////////////////////////////////////////////////////////////////////

 const char* gFS_Header_Extension_FramebufferFetch =
         "#extension GL_NV_shader_framebuffer_fetch : enable\n\n";
 const char* gFS_Header =
         "precision mediump float;\n\n";
 const char* gFS_Uniforms_Color =
         "uniform vec4 color;\n";
 const char* gFS_Uniforms_TextureSampler =
         "uniform sampler2D sampler;\n";
 const char* gFS_Uniforms_GradientSampler[3] = {
         // Linear
         "uniform sampler2D gradientSampler;\n",
         // Circular
         "uniform float gradientRadius;\n"
         "uniform sampler2D gradientSampler;\n",
         // Sweep
         "uniform sampler2D gradientSampler;\n"
 };
 const char* gFS_Uniforms_BitmapSampler =
         "uniform sampler2D bitmapSampler;\n";
 const char* gFS_Uniforms_ColorOp[4] = {
         // None
         "",
         // Matrix
         "uniform mat4 colorMatrix;\n"
         "uniform vec4 colorMatrixVector;\n",
         // Lighting
         "uniform vec4 lightingMul;\n"
         "uniform vec4 lightingAdd;\n",
         // PorterDuff
         "uniform vec4 colorBlend;\n"
 };
 const char* gFS_Main =
         "\nvoid main(void) {\n"
         "    lowp vec4 fragColor;\n";
 const char* gFS_Main_FetchColor =
         "    fragColor = color;\n";
 const char* gFS_Main_FetchTexture =
         "    fragColor = color * texture2D(sampler, outTexCoords);\n";
 const char* gFS_Main_FetchA8Texture =
         "    fragColor = color * texture2D(sampler, outTexCoords).a;\n";
 const char* gFS_Main_FetchGradient[3] = {
         // Linear
         "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
         // Circular
         "    float index = length(circular) * gradientRadius;\n"
         "    vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
         // Sweep
         "    float index = atan(sweep.y, sweep.x) * 0.15915494309; // inv(2 * PI)\n"
         "    vec4 gradientColor = texture2D(gradientSampler, vec2(index - floor(index), 0.5));\n"
 };
 const char* gFS_Main_FetchBitmap =
         "    vec4 bitmapColor = texture2D(bitmapSampler, outBitmapTexCoords);\n";
 const char* gFS_Main_FetchBitmapNpot =
         "    vec4 bitmapColor = texture2D(bitmapSampler, wrap(outBitmapTexCoords));\n";
 const char* gFS_Main_BlendShadersBG =
         "    fragColor = blendShaders(gradientColor, bitmapColor)";
 const char* gFS_Main_BlendShadersGB =
         "    fragColor = blendShaders(bitmapColor, gradientColor)";
 const char* gFS_Main_BlendShaders_Modulate =
         " * fragColor.a;\n";
 const char* gFS_Main_GradientShader_Modulate =
         "    fragColor = gradientColor * fragColor.a;\n";
 const char* gFS_Main_BitmapShader_Modulate =
         "    fragColor = bitmapColor * fragColor.a;\n";
 const char* gFS_Main_FragColor =
         "    gl_FragColor = fragColor;\n";
 const char* gFS_Main_FragColor_Blend =
         "    gl_FragColor = blendFramebuffer(fragColor, gl_LastFragColor);\n";
 const char* gFS_Main_FragColor_Blend_Swap =
         "    gl_FragColor = blendFramebuffer(gl_LastFragColor, fragColor);\n";
 const char* gFS_Main_ApplyColorOp[4] = {
         // None
         "",
         // Matrix
         // TODO: Fix premultiplied alpha computations for color matrix
         "    fragColor *= colorMatrix;\n"
         "    fragColor += colorMatrixVector;\n"
         "    fragColor.rgb *= fragColor.a;\n",
         // Lighting
         "    float lightingAlpha = fragColor.a;\n"
         "    fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
         "    fragColor.a = lightingAlpha;\n",
         // PorterDuff
         "    fragColor = blendColors(colorBlend, fragColor);\n"
 };
 const char* gFS_Footer =
         "}\n\n";

 ///////////////////////////////////////////////////////////////////////////////
 // PorterDuff snippets
 ///////////////////////////////////////////////////////////////////////////////

 const char* gBlendOps[18] = {
         // Clear
         "return vec4(0.0, 0.0, 0.0, 0.0);\n",
         // Src
         "return src;\n",
         // Dst
         "return dst;\n",
         // SrcOver
         "return src + dst * (1.0 - src.a);\n",
         // DstOver
         "return dst + src * (1.0 - dst.a);\n",
         // SrcIn
         "return src * dst.a;\n",
         // DstIn
         "return dst * src.a;\n",
         // SrcOut
         "return src * (1.0 - dst.a);\n",
         // DstOut
         "return dst * (1.0 - src.a);\n",
         // SrcAtop
         "return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
         // DstAtop
         "return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
         // Xor
         "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, "
                 "src.a + dst.a - 2.0 * src.a * dst.a);\n",
         // Add
         "return min(src + dst, 1.0);\n",
         // Multiply
         "return src * dst;\n",
         // Screen
         "return src + dst - src * dst;\n",
         // Overlay
         "return clamp(vec4(mix("
                 "2.0 * src.rgb * dst.rgb + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
                 "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), "
                 "step(dst.a, 2.0 * dst.rgb)), "
                 "src.a + dst.a - src.a * dst.a), 0.0, 1.0);\n",
         // Darken
         "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
                 "min(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
         // Lighten
         "return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
                 "max(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
 };

 ///////////////////////////////////////////////////////////////////////////////
 // Constructors/destructors
 ///////////////////////////////////////////////////////////////////////////////

 ProgramCache::ProgramCache() {
 }

 ProgramCache::~ProgramCache() {
     clear();
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Cache management
 ///////////////////////////////////////////////////////////////////////////////

 void ProgramCache::clear() {
     size_t count = mCache.size();
     for (size_t i = 0; i < count; i++) {
         delete mCache.valueAt(i);
     }
     mCache.clear();
 }

 Program* ProgramCache::get(const ProgramDescription& description) {
     programid key = description.key();
     ssize_t index = mCache.indexOfKey(key);
     Program* program = NULL;
     if (index < 0) {
         description.log("Could not find program");
         program = generateProgram(description, key);
         mCache.add(key, program);
     } else {
         program = mCache.valueAt(index);
     }
     return program;
 }

 ///////////////////////////////////////////////////////////////////////////////
 // Program generation
 ///////////////////////////////////////////////////////////////////////////////

 Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
     String8 vertexShader = generateVertexShader(description);
     String8 fragmentShader = generateFragmentShader(description);

     Program* program = new Program(vertexShader.string(), fragmentShader.string());
     return program;
 }

 String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
     // Add attributes
     String8 shader(gVS_Header_Attributes);
     if (description.hasTexture) {
         shader.append(gVS_Header_Attributes_TexCoords);
     }
     // Uniforms
     shader.append(gVS_Header_Uniforms);
     if (description.hasGradient) {
         shader.append(gVS_Header_Uniforms_HasGradient[description.gradientType]);
     }
     if (description.hasBitmap) {
         shader.append(gVS_Header_Uniforms_HasBitmap);
     }
     // Varyings
     if (description.hasTexture) {
         shader.append(gVS_Header_Varyings_HasTexture);
     }
     if (description.hasGradient) {
         shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
     }
     if (description.hasBitmap) {
         shader.append(gVS_Header_Varyings_HasBitmap);
     }

     // Begin the shader
     shader.append(gVS_Main); {
         if (description.hasTexture) {
             shader.append(gVS_Main_OutTexCoords);
         }
         if (description.hasGradient) {
             shader.append(gVS_Main_OutGradient[description.gradientType]);
         }
         if (description.hasBitmap) {
             shader.append(gVS_Main_OutBitmapTexCoords);
         }
         // Output transformed position
         shader.append(gVS_Main_Position);
     }
     // End the shader
     shader.append(gVS_Footer);

     PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());

     return shader;
 }

 String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
     // Set the default precision
     String8 shader;

     bool blendFramebuffer = description.framebufferMode >= SkXfermode::kPlus_Mode;
     if (blendFramebuffer) {
         shader.append(gFS_Header_Extension_FramebufferFetch);
     }

     shader.append(gFS_Header);

     // Varyings
     if (description.hasTexture) {
         shader.append(gVS_Header_Varyings_HasTexture);
     }
     if (description.hasGradient) {
         shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
     }
     if (description.hasBitmap) {
         shader.append(gVS_Header_Varyings_HasBitmap);
     }


     // Uniforms
     shader.append(gFS_Uniforms_Color);
     if (description.hasTexture) {
         shader.append(gFS_Uniforms_TextureSampler);
     }
     if (description.hasGradient) {
         shader.append(gFS_Uniforms_GradientSampler[description.gradientType]);
     }
     if (description.hasBitmap) {
         shader.append(gFS_Uniforms_BitmapSampler);
     }
     shader.append(gFS_Uniforms_ColorOp[description.colorOp]);

     // Generate required functions
     if (description.hasGradient && description.hasBitmap) {
         generateBlend(shader, "blendShaders", description.shadersMode);
     }
     if (description.colorOp == ProgramDescription::kColorBlend) {
         generateBlend(shader, "blendColors", description.colorMode);
     }
     if (blendFramebuffer) {
         generateBlend(shader, "blendFramebuffer", description.framebufferMode);
     }
     if (description.isBitmapNpot) {
         generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
     }

     // Begin the shader
     shader.append(gFS_Main); {
         // Stores the result in fragColor directly
         if (description.hasTexture) {
             if (description.hasAlpha8Texture) {
                 shader.append(gFS_Main_FetchA8Texture);
             } else {
                 shader.append(gFS_Main_FetchTexture);
             }
         } else {
             shader.append(gFS_Main_FetchColor);
         }
         if (description.hasGradient) {
             shader.append(gFS_Main_FetchGradient[description.gradientType]);
         }
         if (description.hasBitmap) {
             if (!description.isBitmapNpot) {
                 shader.append(gFS_Main_FetchBitmap);
             } else {
                 shader.append(gFS_Main_FetchBitmapNpot);
             }
         }
         // Case when we have two shaders set
         if (description.hasGradient && description.hasBitmap) {
             if (description.isBitmapFirst) {
                 shader.append(gFS_Main_BlendShadersBG);
             } else {
                 shader.append(gFS_Main_BlendShadersGB);
             }
             shader.append(gFS_Main_BlendShaders_Modulate);
         } else {
             if (description.hasGradient) {
                 shader.append(gFS_Main_GradientShader_Modulate);
             } else if (description.hasBitmap) {
                 shader.append(gFS_Main_BitmapShader_Modulate);
             }
         }
         // Apply the color op if needed
         shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
         // Output the fragment
         if (!blendFramebuffer) {
             shader.append(gFS_Main_FragColor);
         } else {
             shader.append(!description.swapSrcDst ?
                     gFS_Main_FragColor_Blend : gFS_Main_FragColor_Blend_Swap);
         }
     }
     // End the shader
     shader.append(gFS_Footer);

     if (DEBUG_PROGRAM_CACHE) {
         PROGRAM_LOGD("*** Generated fragment shader:\n\n");
         printLongString(shader);
     }

     return shader;
 }

 void ProgramCache::generateBlend(String8& shader, const char* name, SkXfermode::Mode mode) {
     shader.append("\nvec4 ");
     shader.append(name);
     shader.append("(vec4 src, vec4 dst) {\n");
     shader.append("    ");
     shader.append(gBlendOps[mode]);
     shader.append("}\n");
 }

 void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
     shader.append("\nvec2 wrap(vec2 texCoords) {\n");
     if (wrapS == GL_MIRRORED_REPEAT) {
         shader.append("    float xMod2 = mod(texCoords.x, 2.0);\n");
         shader.append("    if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
     }
     if (wrapT == GL_MIRRORED_REPEAT) {
         shader.append("    float yMod2 = mod(texCoords.y, 2.0);\n");
         shader.append("    if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
     }
     shader.append("    return vec2(");
     switch (wrapS) {
         case GL_CLAMP_TO_EDGE:
             shader.append("texCoords.x");
             break;
         case GL_REPEAT:
             shader.append("mod(texCoords.x, 1.0)");
             break;
         case GL_MIRRORED_REPEAT:
             shader.append("xMod2");
             break;
     }
     shader.append(", ");
     switch (wrapT) {
         case GL_CLAMP_TO_EDGE:
             shader.append("texCoords.y");
             break;
         case GL_REPEAT:
             shader.append("mod(texCoords.y, 1.0)");
             break;
         case GL_MIRRORED_REPEAT:
             shader.append("yMod2");
             break;
     }
     shader.append(");\n");
     shader.append("}\n");
 }

 void ProgramCache::printLongString(const String8& shader) const {
     ssize_t index = 0;
     ssize_t lastIndex = 0;
     const char* str = shader.string();
     while ((index = shader.find("\n", index)) > -1) {
         String8 line(str, index - lastIndex);
         if (line.length() == 0) line.append("\n");
         PROGRAM_LOGD("%s", line.string());
         index++;
         str += (index - lastIndex);
         lastIndex = index;
     }
 }

 }; // namespace uirenderer
 }; // namespace android
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "OpenGLRenderer"

	#include <utils/String8.h>

	#include "ProgramCache.h"

	namespace android {
	namespace uirenderer {

	///////////////////////////////////////////////////////////////////////////////
	// Vertex shaders snippets
	///////////////////////////////////////////////////////////////////////////////

	const char* gVS_Header_Attributes =
	"attribute vec4 position;\n";
	const char* gVS_Header_Attributes_TexCoords =
	"attribute vec2 texCoords;\n";
	const char* gVS_Header_Uniforms =
	"uniform mat4 transform;\n";
	const char* gVS_Header_Uniforms_HasGradient[3] = {
	// Linear
	"uniform float gradientLength;\n"
	"uniform vec2 gradient;\n"
	"uniform vec2 gradientStart;\n"
	"uniform mat4 screenSpace;\n",
	// Circular
	"uniform vec2 gradientStart;\n"
	"uniform mat4 gradientMatrix;\n"
	"uniform mat4 screenSpace;\n",
	// Sweep
	"uniform vec2 gradientStart;\n"
	"uniform mat4 gradientMatrix;\n"
	"uniform mat4 screenSpace;\n"
	};
	const char* gVS_Header_Uniforms_HasBitmap =
	"uniform mat4 textureTransform;\n"
	"uniform vec2 textureDimension;\n";
	const char* gVS_Header_Varyings_HasTexture =
	"varying vec2 outTexCoords;\n";
	const char* gVS_Header_Varyings_HasBitmap =
	"varying vec2 outBitmapTexCoords;\n";
	const char* gVS_Header_Varyings_HasGradient[3] = {
	// Linear
	"varying float index;\n",
	// Circular
	"varying vec2 circular;\n",
	// Sweep
	"varying vec2 sweep;\n"
	};
	const char* gVS_Main =
	"\nvoid main(void) {\n";
	const char* gVS_Main_OutTexCoords =
	" outTexCoords = texCoords;\n";
	const char* gVS_Main_OutGradient[3] = {
	// Linear
	" vec4 location = screenSpace * position;\n"
	" index = dot(location.xy - gradientStart, gradient) * gradientLength;\n",
	// Circular
	" vec4 location = screenSpace * position;\n"
	" circular = (gradientMatrix * vec4(location.xy - gradientStart, 0.0, 0.0)).xy;\n",
	// Sweep
	" vec4 location = screenSpace * position;\n"
	" sweep = (gradientMatrix * vec4(location.xy - gradientStart, 0.0, 0.0)).xy;\n"
	};
	const char* gVS_Main_OutBitmapTexCoords =
	" vec4 bitmapCoords = textureTransform * position;\n"
	" outBitmapTexCoords = bitmapCoords.xy * textureDimension;\n";
	const char* gVS_Main_Position =
	" gl_Position = transform * position;\n";
	const char* gVS_Footer =
	"}\n\n";

	///////////////////////////////////////////////////////////////////////////////
	// Fragment shaders snippets
	///////////////////////////////////////////////////////////////////////////////

	const char* gFS_Header_Extension_FramebufferFetch =
	"#extension GL_NV_shader_framebuffer_fetch : enable\n\n";
	const char* gFS_Header =
	"precision mediump float;\n\n";
	const char* gFS_Uniforms_Color =
	"uniform vec4 color;\n";
	const char* gFS_Uniforms_TextureSampler =
	"uniform sampler2D sampler;\n";
	const char* gFS_Uniforms_GradientSampler[3] = {
	// Linear
	"uniform sampler2D gradientSampler;\n",
	// Circular
	"uniform float gradientRadius;\n"
	"uniform sampler2D gradientSampler;\n",
	// Sweep
	"uniform sampler2D gradientSampler;\n"
	};
	const char* gFS_Uniforms_BitmapSampler =
	"uniform sampler2D bitmapSampler;\n";
	const char* gFS_Uniforms_ColorOp[4] = {
	// None
	"",
	// Matrix
	"uniform mat4 colorMatrix;\n"
	"uniform vec4 colorMatrixVector;\n",
	// Lighting
	"uniform vec4 lightingMul;\n"
	"uniform vec4 lightingAdd;\n",
	// PorterDuff
	"uniform vec4 colorBlend;\n"
	};
	const char* gFS_Main =
	"\nvoid main(void) {\n"
	" lowp vec4 fragColor;\n";
	const char* gFS_Main_FetchColor =
	" fragColor = color;\n";
	const char* gFS_Main_FetchTexture =
	" fragColor = color * texture2D(sampler, outTexCoords);\n";
	const char* gFS_Main_FetchA8Texture =
	" fragColor = color * texture2D(sampler, outTexCoords).a;\n";
	const char* gFS_Main_FetchGradient[3] = {
	// Linear
	" vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
	// Circular
	" float index = length(circular) * gradientRadius;\n"
	" vec4 gradientColor = texture2D(gradientSampler, vec2(index, 0.5));\n",
	// Sweep
	" float index = atan(sweep.y, sweep.x) * 0.15915494309; // inv(2 * PI)\n"
	" vec4 gradientColor = texture2D(gradientSampler, vec2(index - floor(index), 0.5));\n"
	};
	const char* gFS_Main_FetchBitmap =
	" vec4 bitmapColor = texture2D(bitmapSampler, outBitmapTexCoords);\n";
	const char* gFS_Main_FetchBitmapNpot =
	" vec4 bitmapColor = texture2D(bitmapSampler, wrap(outBitmapTexCoords));\n";
	const char* gFS_Main_BlendShadersBG =
	" fragColor = blendShaders(gradientColor, bitmapColor)";
	const char* gFS_Main_BlendShadersGB =
	" fragColor = blendShaders(bitmapColor, gradientColor)";
	const char* gFS_Main_BlendShaders_Modulate =
	" * fragColor.a;\n";
	const char* gFS_Main_GradientShader_Modulate =
	" fragColor = gradientColor * fragColor.a;\n";
	const char* gFS_Main_BitmapShader_Modulate =
	" fragColor = bitmapColor * fragColor.a;\n";
	const char* gFS_Main_FragColor =
	" gl_FragColor = fragColor;\n";
	const char* gFS_Main_FragColor_Blend =
	" gl_FragColor = blendFramebuffer(fragColor, gl_LastFragColor);\n";
	const char* gFS_Main_FragColor_Blend_Swap =
	" gl_FragColor = blendFramebuffer(gl_LastFragColor, fragColor);\n";
	const char* gFS_Main_ApplyColorOp[4] = {
	// None
	"",
	// Matrix
	// TODO: Fix premultiplied alpha computations for color matrix
	" fragColor *= colorMatrix;\n"
	" fragColor += colorMatrixVector;\n"
	" fragColor.rgb *= fragColor.a;\n",
	// Lighting
	" float lightingAlpha = fragColor.a;\n"
	" fragColor = min(fragColor * lightingMul + (lightingAdd * lightingAlpha), lightingAlpha);\n"
	" fragColor.a = lightingAlpha;\n",
	// PorterDuff
	" fragColor = blendColors(colorBlend, fragColor);\n"
	};
	const char* gFS_Footer =
	"}\n\n";

	///////////////////////////////////////////////////////////////////////////////
	// PorterDuff snippets
	///////////////////////////////////////////////////////////////////////////////

	const char* gBlendOps[18] = {
	// Clear
	"return vec4(0.0, 0.0, 0.0, 0.0);\n",
	// Src
	"return src;\n",
	// Dst
	"return dst;\n",
	// SrcOver
	"return src + dst * (1.0 - src.a);\n",
	// DstOver
	"return dst + src * (1.0 - dst.a);\n",
	// SrcIn
	"return src * dst.a;\n",
	// DstIn
	"return dst * src.a;\n",
	// SrcOut
	"return src * (1.0 - dst.a);\n",
	// DstOut
	"return dst * (1.0 - src.a);\n",
	// SrcAtop
	"return vec4(src.rgb * dst.a + (1.0 - src.a) * dst.rgb, dst.a);\n",
	// DstAtop
	"return vec4(dst.rgb * src.a + (1.0 - dst.a) * src.rgb, src.a);\n",
	// Xor
	"return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb, "
	"src.a + dst.a - 2.0 * src.a * dst.a);\n",
	// Add
	"return min(src + dst, 1.0);\n",
	// Multiply
	"return src * dst;\n",
	// Screen
	"return src + dst - src * dst;\n",
	// Overlay
	"return clamp(vec4(mix("
	"2.0 * src.rgb * dst.rgb + src.rgb * (1.0 - dst.a) + dst.rgb * (1.0 - src.a), "
	"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), "
	"step(dst.a, 2.0 * dst.rgb)), "
	"src.a + dst.a - src.a * dst.a), 0.0, 1.0);\n",
	// Darken
	"return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
	"min(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
	// Lighten
	"return vec4(src.rgb * (1.0 - dst.a) + (1.0 - src.a) * dst.rgb + "
	"max(src.rgb * dst.a, dst.rgb * src.a), src.a + dst.a - src.a * dst.a);\n",
	};

	///////////////////////////////////////////////////////////////////////////////
	// Constructors/destructors
	///////////////////////////////////////////////////////////////////////////////

	ProgramCache::ProgramCache() {
	}

	ProgramCache::~ProgramCache() {
	clear();
	}

	///////////////////////////////////////////////////////////////////////////////
	// Cache management
	///////////////////////////////////////////////////////////////////////////////

	void ProgramCache::clear() {
	size_t count = mCache.size();
	for (size_t i = 0; i < count; i++) {
	delete mCache.valueAt(i);
	}
	mCache.clear();
	}

	Program* ProgramCache::get(const ProgramDescription& description) {
	programid key = description.key();
	ssize_t index = mCache.indexOfKey(key);
	Program* program = NULL;
	if (index < 0) {
	description.log("Could not find program");
	program = generateProgram(description, key);
	mCache.add(key, program);
	} else {
	program = mCache.valueAt(index);
	}
	return program;
	}

	///////////////////////////////////////////////////////////////////////////////
	// Program generation
	///////////////////////////////////////////////////////////////////////////////

	Program* ProgramCache::generateProgram(const ProgramDescription& description, programid key) {
	String8 vertexShader = generateVertexShader(description);
	String8 fragmentShader = generateFragmentShader(description);

	Program* program = new Program(vertexShader.string(), fragmentShader.string());
	return program;
	}

	String8 ProgramCache::generateVertexShader(const ProgramDescription& description) {
	// Add attributes
	String8 shader(gVS_Header_Attributes);
	if (description.hasTexture) {
	shader.append(gVS_Header_Attributes_TexCoords);
	}
	// Uniforms
	shader.append(gVS_Header_Uniforms);
	if (description.hasGradient) {
	shader.append(gVS_Header_Uniforms_HasGradient[description.gradientType]);
	}
	if (description.hasBitmap) {
	shader.append(gVS_Header_Uniforms_HasBitmap);
	}
	// Varyings
	if (description.hasTexture) {
	shader.append(gVS_Header_Varyings_HasTexture);
	}
	if (description.hasGradient) {
	shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
	}
	if (description.hasBitmap) {
	shader.append(gVS_Header_Varyings_HasBitmap);
	}

	// Begin the shader
	shader.append(gVS_Main); {
	if (description.hasTexture) {
	shader.append(gVS_Main_OutTexCoords);
	}
	if (description.hasGradient) {
	shader.append(gVS_Main_OutGradient[description.gradientType]);
	}
	if (description.hasBitmap) {
	shader.append(gVS_Main_OutBitmapTexCoords);
	}
	// Output transformed position
	shader.append(gVS_Main_Position);
	}
	// End the shader
	shader.append(gVS_Footer);

	PROGRAM_LOGD("*** Generated vertex shader:\n\n%s", shader.string());

	return shader;
	}

	String8 ProgramCache::generateFragmentShader(const ProgramDescription& description) {
	// Set the default precision
	String8 shader;

	bool blendFramebuffer = description.framebufferMode >= SkXfermode::kPlus_Mode;
	if (blendFramebuffer) {
	shader.append(gFS_Header_Extension_FramebufferFetch);
	}

	shader.append(gFS_Header);

	// Varyings
	if (description.hasTexture) {
	shader.append(gVS_Header_Varyings_HasTexture);
	}
	if (description.hasGradient) {
	shader.append(gVS_Header_Varyings_HasGradient[description.gradientType]);
	}
	if (description.hasBitmap) {
	shader.append(gVS_Header_Varyings_HasBitmap);
	}


	// Uniforms
	shader.append(gFS_Uniforms_Color);
	if (description.hasTexture) {
	shader.append(gFS_Uniforms_TextureSampler);
	}
	if (description.hasGradient) {
	shader.append(gFS_Uniforms_GradientSampler[description.gradientType]);
	}
	if (description.hasBitmap) {
	shader.append(gFS_Uniforms_BitmapSampler);
	}
	shader.append(gFS_Uniforms_ColorOp[description.colorOp]);

	// Generate required functions
	if (description.hasGradient && description.hasBitmap) {
	generateBlend(shader, "blendShaders", description.shadersMode);
	}
	if (description.colorOp == ProgramDescription::kColorBlend) {
	generateBlend(shader, "blendColors", description.colorMode);
	}
	if (blendFramebuffer) {
	generateBlend(shader, "blendFramebuffer", description.framebufferMode);
	}
	if (description.isBitmapNpot) {
	generateTextureWrap(shader, description.bitmapWrapS, description.bitmapWrapT);
	}

	// Begin the shader
	shader.append(gFS_Main); {
	// Stores the result in fragColor directly
	if (description.hasTexture) {
	if (description.hasAlpha8Texture) {
	shader.append(gFS_Main_FetchA8Texture);
	} else {
	shader.append(gFS_Main_FetchTexture);
	}
	} else {
	shader.append(gFS_Main_FetchColor);
	}
	if (description.hasGradient) {
	shader.append(gFS_Main_FetchGradient[description.gradientType]);
	}
	if (description.hasBitmap) {
	if (!description.isBitmapNpot) {
	shader.append(gFS_Main_FetchBitmap);
	} else {
	shader.append(gFS_Main_FetchBitmapNpot);
	}
	}
	// Case when we have two shaders set
	if (description.hasGradient && description.hasBitmap) {
	if (description.isBitmapFirst) {
	shader.append(gFS_Main_BlendShadersBG);
	} else {
	shader.append(gFS_Main_BlendShadersGB);
	}
	shader.append(gFS_Main_BlendShaders_Modulate);
	} else {
	if (description.hasGradient) {
	shader.append(gFS_Main_GradientShader_Modulate);
	} else if (description.hasBitmap) {
	shader.append(gFS_Main_BitmapShader_Modulate);
	}
	}
	// Apply the color op if needed
	shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
	// Output the fragment
	if (!blendFramebuffer) {
	shader.append(gFS_Main_FragColor);
	} else {
	shader.append(!description.swapSrcDst ?
	gFS_Main_FragColor_Blend : gFS_Main_FragColor_Blend_Swap);
	}
	}
	// End the shader
	shader.append(gFS_Footer);

	if (DEBUG_PROGRAM_CACHE) {
	PROGRAM_LOGD("*** Generated fragment shader:\n\n");
	printLongString(shader);
	}

	return shader;
	}

	void ProgramCache::generateBlend(String8& shader, const char* name, SkXfermode::Mode mode) {
	shader.append("\nvec4 ");
	shader.append(name);
	shader.append("(vec4 src, vec4 dst) {\n");
	shader.append(" ");
	shader.append(gBlendOps[mode]);
	shader.append("}\n");
	}

	void ProgramCache::generateTextureWrap(String8& shader, GLenum wrapS, GLenum wrapT) {
	shader.append("\nvec2 wrap(vec2 texCoords) {\n");
	if (wrapS == GL_MIRRORED_REPEAT) {
	shader.append(" float xMod2 = mod(texCoords.x, 2.0);\n");
	shader.append(" if (xMod2 > 1.0) xMod2 = 2.0 - xMod2;\n");
	}
	if (wrapT == GL_MIRRORED_REPEAT) {
	shader.append(" float yMod2 = mod(texCoords.y, 2.0);\n");
	shader.append(" if (yMod2 > 1.0) yMod2 = 2.0 - yMod2;\n");
	}
	shader.append(" return vec2(");
	switch (wrapS) {
	case GL_CLAMP_TO_EDGE:
	shader.append("texCoords.x");
	break;
	case GL_REPEAT:
	shader.append("mod(texCoords.x, 1.0)");
	break;
	case GL_MIRRORED_REPEAT:
	shader.append("xMod2");
	break;
	}
	shader.append(", ");
	switch (wrapT) {
	case GL_CLAMP_TO_EDGE:
	shader.append("texCoords.y");
	break;
	case GL_REPEAT:
	shader.append("mod(texCoords.y, 1.0)");
	break;
	case GL_MIRRORED_REPEAT:
	shader.append("yMod2");
	break;
	}
	shader.append(");\n");
	shader.append("}\n");
	}

	void ProgramCache::printLongString(const String8& shader) const {
	ssize_t index = 0;
	ssize_t lastIndex = 0;
	const char* str = shader.string();
	while ((index = shader.find("\n", index)) > -1) {
	String8 line(str, index - lastIndex);
	if (line.length() == 0) line.append("\n");
	PROGRAM_LOGD("%s", line.string());
	index++;
	str += (index - lastIndex);
	lastIndex = index;
	}
	}

	}; // namespace uirenderer
	}; // namespace android