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Unified Diff: components/display_compositor/gl_helper_scaling.cc

Issue 2873243002: Move components/display_compositor to components/viz/display_compositor (Closed)
Patch Set: Rebase Created 3 years, 7 months ago
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Index: components/display_compositor/gl_helper_scaling.cc
diff --git a/components/display_compositor/gl_helper_scaling.cc b/components/display_compositor/gl_helper_scaling.cc
deleted file mode 100644
index ec6c057d235545a28437957e08295d3d520bbabb..0000000000000000000000000000000000000000
--- a/components/display_compositor/gl_helper_scaling.cc
+++ /dev/null
@@ -1,881 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "components/display_compositor/gl_helper_scaling.h"
-
-#include <stddef.h>
-
-#include <deque>
-#include <string>
-#include <vector>
-
-#include "base/bind.h"
-#include "base/lazy_instance.h"
-#include "base/logging.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/message_loop/message_loop.h"
-#include "base/time/time.h"
-#include "base/trace_event/trace_event.h"
-#include "gpu/command_buffer/client/gles2_interface.h"
-#include "third_party/skia/include/core/SkRegion.h"
-#include "ui/gfx/geometry/rect.h"
-#include "ui/gfx/geometry/size.h"
-
-using gpu::gles2::GLES2Interface;
-
-namespace display_compositor {
-
-GLHelperScaling::GLHelperScaling(GLES2Interface* gl, GLHelper* helper)
- : gl_(gl), helper_(helper), vertex_attributes_buffer_(gl_) {
- InitBuffer();
-}
-
-GLHelperScaling::~GLHelperScaling() {}
-
-// Used to keep track of a generated shader program. The program
-// is passed in as text through Setup and is used by calling
-// UseProgram() with the right parameters. Note that |gl_|
-// and |helper_| are assumed to live longer than this program.
-class ShaderProgram : public base::RefCounted<ShaderProgram> {
- public:
- ShaderProgram(GLES2Interface* gl, GLHelper* helper)
- : gl_(gl),
- helper_(helper),
- program_(gl_->CreateProgram()),
- position_location_(-1),
- texcoord_location_(-1),
- src_subrect_location_(-1),
- src_pixelsize_location_(-1),
- dst_pixelsize_location_(-1),
- scaling_vector_location_(-1),
- color_weights_location_(-1) {}
-
- // Compile shader program.
- void Setup(const GLchar* vertex_shader_text,
- const GLchar* fragment_shader_text);
-
- // UseProgram must be called with GL_TEXTURE_2D bound to the
- // source texture and GL_ARRAY_BUFFER bound to a vertex
- // attribute buffer.
- void UseProgram(const gfx::Size& src_size,
- const gfx::Rect& src_subrect,
- const gfx::Size& dst_size,
- bool scale_x,
- bool flip_y,
- GLfloat color_weights[4]);
-
- bool Initialized() const { return position_location_ != -1; }
-
- private:
- friend class base::RefCounted<ShaderProgram>;
- ~ShaderProgram() { gl_->DeleteProgram(program_); }
-
- GLES2Interface* gl_;
- GLHelper* helper_;
-
- // A program for copying a source texture into a destination texture.
- GLuint program_;
-
- // The location of the position in the program.
- GLint position_location_;
- // The location of the texture coordinate in the program.
- GLint texcoord_location_;
- // The location of the source texture in the program.
- GLint texture_location_;
- // The location of the texture coordinate of
- // the sub-rectangle in the program.
- GLint src_subrect_location_;
- // Location of size of source image in pixels.
- GLint src_pixelsize_location_;
- // Location of size of destination image in pixels.
- GLint dst_pixelsize_location_;
- // Location of vector for scaling direction.
- GLint scaling_vector_location_;
- // Location of color weights.
- GLint color_weights_location_;
-
- DISALLOW_COPY_AND_ASSIGN(ShaderProgram);
-};
-
-// Implementation of a single stage in a scaler pipeline. If the pipeline has
-// multiple stages, it calls Scale() on the subscaler, then further scales the
-// output. Caches textures and framebuffers to avoid allocating/deleting
-// them once per frame, which can be expensive on some drivers.
-class ScalerImpl : public GLHelper::ScalerInterface,
- public GLHelperScaling::ShaderInterface {
- public:
- // |gl| and |copy_impl| are expected to live longer than this object.
- // |src_size| is the size of the input texture in pixels.
- // |dst_size| is the size of the output texutre in pixels.
- // |src_subrect| is the portion of the src to copy to the output texture.
- // If |scale_x| is true, we are scaling along the X axis, otherwise Y.
- // If we are scaling in both X and Y, |scale_x| is ignored.
- // If |vertically_flip_texture| is true, output will be upside-down.
- // If |swizzle| is true, RGBA will be transformed into BGRA.
- // |color_weights| are only used together with SHADER_PLANAR to specify
- // how to convert RGB colors into a single value.
- ScalerImpl(GLES2Interface* gl,
- GLHelperScaling* scaler_helper,
- const GLHelperScaling::ScalerStage& scaler_stage,
- ScalerImpl* subscaler,
- const float* color_weights)
- : gl_(gl),
- scaler_helper_(scaler_helper),
- spec_(scaler_stage),
- intermediate_texture_(0),
- dst_framebuffer_(gl),
- subscaler_(subscaler) {
- if (color_weights) {
- color_weights_[0] = color_weights[0];
- color_weights_[1] = color_weights[1];
- color_weights_[2] = color_weights[2];
- color_weights_[3] = color_weights[3];
- } else {
- color_weights_[0] = 0.0;
- color_weights_[1] = 0.0;
- color_weights_[2] = 0.0;
- color_weights_[3] = 0.0;
- }
- shader_program_ =
- scaler_helper_->GetShaderProgram(spec_.shader, spec_.swizzle);
-
- if (subscaler_) {
- intermediate_texture_ = 0u;
- gl_->GenTextures(1, &intermediate_texture_);
- ScopedTextureBinder<GL_TEXTURE_2D> texture_binder(gl_,
- intermediate_texture_);
- gl_->TexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, spec_.src_size.width(),
- spec_.src_size.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE,
- NULL);
- }
- }
-
- ~ScalerImpl() override {
- if (intermediate_texture_) {
- gl_->DeleteTextures(1, &intermediate_texture_);
- }
- }
-
- // GLHelperShader::ShaderInterface implementation.
- void Execute(GLuint source_texture,
- const std::vector<GLuint>& dest_textures) override {
- if (subscaler_) {
- subscaler_->Scale(source_texture, intermediate_texture_);
- source_texture = intermediate_texture_;
- }
-
- ScopedFramebufferBinder<GL_FRAMEBUFFER> framebuffer_binder(
- gl_, dst_framebuffer_);
- DCHECK_GT(dest_textures.size(), 0U);
- std::unique_ptr<GLenum[]> buffers(new GLenum[dest_textures.size()]);
- for (size_t t = 0; t < dest_textures.size(); t++) {
- ScopedTextureBinder<GL_TEXTURE_2D> texture_binder(gl_, dest_textures[t]);
- gl_->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + t,
- GL_TEXTURE_2D, dest_textures[t], 0);
- buffers[t] = GL_COLOR_ATTACHMENT0 + t;
- }
- ScopedTextureBinder<GL_TEXTURE_2D> texture_binder(gl_, source_texture);
-
- gl_->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
- gl_->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
- gl_->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
- gl_->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-
- ScopedBufferBinder<GL_ARRAY_BUFFER> buffer_binder(
- gl_, scaler_helper_->vertex_attributes_buffer_);
- shader_program_->UseProgram(spec_.src_size, spec_.src_subrect,
- spec_.dst_size, spec_.scale_x,
- spec_.vertically_flip_texture, color_weights_);
- gl_->Viewport(0, 0, spec_.dst_size.width(), spec_.dst_size.height());
-
- if (dest_textures.size() > 1) {
- DCHECK_LE(static_cast<int>(dest_textures.size()),
- scaler_helper_->helper_->MaxDrawBuffers());
- gl_->DrawBuffersEXT(dest_textures.size(), buffers.get());
- }
- // Conduct texture mapping by drawing a quad composed of two triangles.
- gl_->DrawArrays(GL_TRIANGLE_STRIP, 0, 4);
- if (dest_textures.size() > 1) {
- // Set the draw buffers back to not confuse others.
- gl_->DrawBuffersEXT(1, &buffers[0]);
- }
- }
-
- // GLHelper::ScalerInterface implementation.
- void Scale(GLuint source_texture, GLuint dest_texture) override {
- std::vector<GLuint> tmp(1);
- tmp[0] = dest_texture;
- Execute(source_texture, tmp);
- }
-
- const gfx::Size& SrcSize() override {
- if (subscaler_) {
- return subscaler_->SrcSize();
- }
- return spec_.src_size;
- }
- const gfx::Rect& SrcSubrect() override {
- if (subscaler_) {
- return subscaler_->SrcSubrect();
- }
- return spec_.src_subrect;
- }
- const gfx::Size& DstSize() override { return spec_.dst_size; }
-
- private:
- GLES2Interface* gl_;
- GLHelperScaling* scaler_helper_;
- GLHelperScaling::ScalerStage spec_;
- GLfloat color_weights_[4];
- GLuint intermediate_texture_;
- scoped_refptr<ShaderProgram> shader_program_;
- ScopedFramebuffer dst_framebuffer_;
- std::unique_ptr<ScalerImpl> subscaler_;
-};
-
-GLHelperScaling::ScalerStage::ScalerStage(ShaderType shader_,
- gfx::Size src_size_,
- gfx::Rect src_subrect_,
- gfx::Size dst_size_,
- bool scale_x_,
- bool vertically_flip_texture_,
- bool swizzle_)
- : shader(shader_),
- src_size(src_size_),
- src_subrect(src_subrect_),
- dst_size(dst_size_),
- scale_x(scale_x_),
- vertically_flip_texture(vertically_flip_texture_),
- swizzle(swizzle_) {}
-
-GLHelperScaling::ScalerStage::ScalerStage(const ScalerStage& other) = default;
-
-// The important inputs for this function is |x_ops| and
-// |y_ops|. They represent scaling operations to be done
-// on an imag of size |src_size|. If |quality| is SCALER_QUALITY_BEST,
-// then we will interpret these scale operations literally and we'll
-// create one scaler stage for each ScaleOp. However, if |quality|
-// is SCALER_QUALITY_GOOD, then we can do a whole bunch of optimizations
-// by combining two or more ScaleOps in to a single scaler stage.
-// Normally we process ScaleOps from |y_ops| first and |x_ops| after
-// all |y_ops| are processed, but sometimes we can combine one or more
-// operation from both queues essentially for free. This is the reason
-// why |x_ops| and |y_ops| aren't just one single queue.
-void GLHelperScaling::ConvertScalerOpsToScalerStages(
- GLHelper::ScalerQuality quality,
- gfx::Size src_size,
- gfx::Rect src_subrect,
- const gfx::Size& dst_size,
- bool vertically_flip_texture,
- bool swizzle,
- std::deque<GLHelperScaling::ScaleOp>* x_ops,
- std::deque<GLHelperScaling::ScaleOp>* y_ops,
- std::vector<ScalerStage>* scaler_stages) {
- while (!x_ops->empty() || !y_ops->empty()) {
- gfx::Size intermediate_size = src_subrect.size();
- std::deque<ScaleOp>* current_queue = NULL;
-
- if (!y_ops->empty()) {
- current_queue = y_ops;
- } else {
- current_queue = x_ops;
- }
-
- ShaderType current_shader = SHADER_BILINEAR;
- switch (current_queue->front().scale_factor) {
- case 0:
- if (quality == GLHelper::SCALER_QUALITY_BEST) {
- current_shader = SHADER_BICUBIC_UPSCALE;
- }
- break;
- case 2:
- if (quality == GLHelper::SCALER_QUALITY_BEST) {
- current_shader = SHADER_BICUBIC_HALF_1D;
- }
- break;
- case 3:
- DCHECK(quality != GLHelper::SCALER_QUALITY_BEST);
- current_shader = SHADER_BILINEAR3;
- break;
- default:
- NOTREACHED();
- }
- bool scale_x = current_queue->front().scale_x;
- current_queue->front().UpdateSize(&intermediate_size);
- current_queue->pop_front();
-
- // Optimization: Sometimes we can combine 2-4 scaling operations into
- // one operation.
- if (quality == GLHelper::SCALER_QUALITY_GOOD) {
- if (!current_queue->empty() && current_shader == SHADER_BILINEAR) {
- // Combine two steps in the same dimension.
- current_queue->front().UpdateSize(&intermediate_size);
- current_queue->pop_front();
- current_shader = SHADER_BILINEAR2;
- if (!current_queue->empty()) {
- // Combine three steps in the same dimension.
- current_queue->front().UpdateSize(&intermediate_size);
- current_queue->pop_front();
- current_shader = SHADER_BILINEAR4;
- }
- }
- // Check if we can combine some steps in the other dimension as well.
- // Since all shaders currently use GL_LINEAR, we can easily scale up
- // or scale down by exactly 2x at the same time as we do another
- // operation. Currently, the following mergers are supported:
- // * 1 bilinear Y-pass with 1 bilinear X-pass (up or down)
- // * 2 bilinear Y-passes with 2 bilinear X-passes
- // * 1 bilinear Y-pass with N bilinear X-pass
- // * N bilinear Y-passes with 1 bilinear X-pass (down only)
- // Measurements indicate that generalizing this for 3x3 and 4x4
- // makes it slower on some platforms, such as the Pixel.
- if (!scale_x && x_ops->size() > 0 && x_ops->front().scale_factor <= 2) {
- int x_passes = 0;
- if (current_shader == SHADER_BILINEAR2 && x_ops->size() >= 2) {
- // 2y + 2x passes
- x_passes = 2;
- current_shader = SHADER_BILINEAR2X2;
- } else if (current_shader == SHADER_BILINEAR) {
- // 1y + Nx passes
- scale_x = true;
- switch (x_ops->size()) {
- case 0:
- NOTREACHED();
- case 1:
- if (x_ops->front().scale_factor == 3) {
- current_shader = SHADER_BILINEAR3;
- }
- x_passes = 1;
- break;
- case 2:
- x_passes = 2;
- current_shader = SHADER_BILINEAR2;
- break;
- default:
- x_passes = 3;
- current_shader = SHADER_BILINEAR4;
- break;
- }
- } else if (x_ops->front().scale_factor == 2) {
- // Ny + 1x-downscale
- x_passes = 1;
- }
-
- for (int i = 0; i < x_passes; i++) {
- x_ops->front().UpdateSize(&intermediate_size);
- x_ops->pop_front();
- }
- }
- }
-
- scaler_stages->push_back(ScalerStage(current_shader, src_size, src_subrect,
- intermediate_size, scale_x,
- vertically_flip_texture, swizzle));
- src_size = intermediate_size;
- src_subrect = gfx::Rect(intermediate_size);
- vertically_flip_texture = false;
- swizzle = false;
- }
-}
-
-void GLHelperScaling::ComputeScalerStages(
- GLHelper::ScalerQuality quality,
- const gfx::Size& src_size,
- const gfx::Rect& src_subrect,
- const gfx::Size& dst_size,
- bool vertically_flip_texture,
- bool swizzle,
- std::vector<ScalerStage>* scaler_stages) {
- if (quality == GLHelper::SCALER_QUALITY_FAST ||
- src_subrect.size() == dst_size) {
- scaler_stages->push_back(ScalerStage(SHADER_BILINEAR, src_size, src_subrect,
- dst_size, false,
- vertically_flip_texture, swizzle));
- return;
- }
-
- std::deque<GLHelperScaling::ScaleOp> x_ops, y_ops;
- GLHelperScaling::ScaleOp::AddOps(src_subrect.width(), dst_size.width(), true,
- quality == GLHelper::SCALER_QUALITY_GOOD,
- &x_ops);
- GLHelperScaling::ScaleOp::AddOps(
- src_subrect.height(), dst_size.height(), false,
- quality == GLHelper::SCALER_QUALITY_GOOD, &y_ops);
-
- ConvertScalerOpsToScalerStages(quality, src_size, src_subrect, dst_size,
- vertically_flip_texture, swizzle, &x_ops,
- &y_ops, scaler_stages);
-}
-
-GLHelper::ScalerInterface* GLHelperScaling::CreateScaler(
- GLHelper::ScalerQuality quality,
- gfx::Size src_size,
- gfx::Rect src_subrect,
- const gfx::Size& dst_size,
- bool vertically_flip_texture,
- bool swizzle) {
- std::vector<ScalerStage> scaler_stages;
- ComputeScalerStages(quality, src_size, src_subrect, dst_size,
- vertically_flip_texture, swizzle, &scaler_stages);
-
- ScalerImpl* ret = NULL;
- for (unsigned int i = 0; i < scaler_stages.size(); i++) {
- ret = new ScalerImpl(gl_, this, scaler_stages[i], ret, NULL);
- }
- return ret;
-}
-
-GLHelper::ScalerInterface* GLHelperScaling::CreatePlanarScaler(
- const gfx::Size& src_size,
- const gfx::Rect& src_subrect,
- const gfx::Size& dst_size,
- bool vertically_flip_texture,
- bool swizzle,
- const float color_weights[4]) {
- ScalerStage stage(SHADER_PLANAR, src_size, src_subrect, dst_size, true,
- vertically_flip_texture, swizzle);
- return new ScalerImpl(gl_, this, stage, NULL, color_weights);
-}
-
-GLHelperScaling::ShaderInterface* GLHelperScaling::CreateYuvMrtShader(
- const gfx::Size& src_size,
- const gfx::Rect& src_subrect,
- const gfx::Size& dst_size,
- bool vertically_flip_texture,
- bool swizzle,
- ShaderType shader) {
- DCHECK(shader == SHADER_YUV_MRT_PASS1 || shader == SHADER_YUV_MRT_PASS2);
- ScalerStage stage(shader, src_size, src_subrect, dst_size, true,
- vertically_flip_texture, swizzle);
- return new ScalerImpl(gl_, this, stage, NULL, NULL);
-}
-
-const GLfloat GLHelperScaling::kVertexAttributes[] = {
- -1.0f, -1.0f, 0.0f, 0.0f, // vertex 0
- 1.0f, -1.0f, 1.0f, 0.0f, // vertex 1
- -1.0f, 1.0f, 0.0f, 1.0f, // vertex 2
- 1.0f, 1.0f, 1.0f, 1.0f,
-}; // vertex 3
-
-void GLHelperScaling::InitBuffer() {
- ScopedBufferBinder<GL_ARRAY_BUFFER> buffer_binder(gl_,
- vertex_attributes_buffer_);
- gl_->BufferData(GL_ARRAY_BUFFER, sizeof(kVertexAttributes), kVertexAttributes,
- GL_STATIC_DRAW);
-}
-
-scoped_refptr<ShaderProgram> GLHelperScaling::GetShaderProgram(ShaderType type,
- bool swizzle) {
- ShaderProgramKeyType key(type, swizzle);
- scoped_refptr<ShaderProgram>& cache_entry(shader_programs_[key]);
- if (!cache_entry.get()) {
- cache_entry = new ShaderProgram(gl_, helper_);
- std::basic_string<GLchar> vertex_program;
- std::basic_string<GLchar> fragment_program;
- std::basic_string<GLchar> vertex_header;
- std::basic_string<GLchar> fragment_directives;
- std::basic_string<GLchar> fragment_header;
- std::basic_string<GLchar> shared_variables;
-
- vertex_header.append(
- "precision highp float;\n"
- "attribute vec2 a_position;\n"
- "attribute vec2 a_texcoord;\n"
- "uniform vec4 src_subrect;\n");
-
- fragment_header.append(
- "precision mediump float;\n"
- "uniform sampler2D s_texture;\n");
-
- vertex_program.append(
- " gl_Position = vec4(a_position, 0.0, 1.0);\n"
- " vec2 texcoord = src_subrect.xy + a_texcoord * src_subrect.zw;\n");
-
- switch (type) {
- case SHADER_BILINEAR:
- shared_variables.append("varying vec2 v_texcoord;\n");
- vertex_program.append(" v_texcoord = texcoord;\n");
- fragment_program.append(
- " gl_FragColor = texture2D(s_texture, v_texcoord);\n");
- break;
-
- case SHADER_BILINEAR2:
- // This is equivialent to two passes of the BILINEAR shader above.
- // It can be used to scale an image down 1.0x-2.0x in either dimension,
- // or exactly 4x.
- shared_variables.append(
- "varying vec4 v_texcoords;\n"); // 2 texcoords packed in one quad
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 4.0;\n"
- " v_texcoords.xy = texcoord + step;\n"
- " v_texcoords.zw = texcoord - step;\n");
-
- fragment_program.append(
- " gl_FragColor = (texture2D(s_texture, v_texcoords.xy) +\n"
- " texture2D(s_texture, v_texcoords.zw)) / 2.0;\n");
- break;
-
- case SHADER_BILINEAR3:
- // This is kind of like doing 1.5 passes of the BILINEAR shader.
- // It can be used to scale an image down 1.5x-3.0x, or exactly 6x.
- shared_variables.append(
- "varying vec4 v_texcoords1;\n" // 2 texcoords packed in one quad
- "varying vec2 v_texcoords2;\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 3.0;\n"
- " v_texcoords1.xy = texcoord + step;\n"
- " v_texcoords1.zw = texcoord;\n"
- " v_texcoords2 = texcoord - step;\n");
- fragment_program.append(
- " gl_FragColor = (texture2D(s_texture, v_texcoords1.xy) +\n"
- " texture2D(s_texture, v_texcoords1.zw) +\n"
- " texture2D(s_texture, v_texcoords2)) / 3.0;\n");
- break;
-
- case SHADER_BILINEAR4:
- // This is equivialent to three passes of the BILINEAR shader above,
- // It can be used to scale an image down 2.0x-4.0x or exactly 8x.
- shared_variables.append("varying vec4 v_texcoords[2];\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 8.0;\n"
- " v_texcoords[0].xy = texcoord - step * 3.0;\n"
- " v_texcoords[0].zw = texcoord - step;\n"
- " v_texcoords[1].xy = texcoord + step;\n"
- " v_texcoords[1].zw = texcoord + step * 3.0;\n");
- fragment_program.append(
- " gl_FragColor = (\n"
- " texture2D(s_texture, v_texcoords[0].xy) +\n"
- " texture2D(s_texture, v_texcoords[0].zw) +\n"
- " texture2D(s_texture, v_texcoords[1].xy) +\n"
- " texture2D(s_texture, v_texcoords[1].zw)) / 4.0;\n");
- break;
-
- case SHADER_BILINEAR2X2:
- // This is equivialent to four passes of the BILINEAR shader above.
- // Two in each dimension. It can be used to scale an image down
- // 1.0x-2.0x in both X and Y directions. Or, it could be used to
- // scale an image down by exactly 4x in both dimensions.
- shared_variables.append("varying vec4 v_texcoords[2];\n");
- vertex_header.append("uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = src_subrect.zw / 4.0 / dst_pixelsize;\n"
- " v_texcoords[0].xy = texcoord + vec2(step.x, step.y);\n"
- " v_texcoords[0].zw = texcoord + vec2(step.x, -step.y);\n"
- " v_texcoords[1].xy = texcoord + vec2(-step.x, step.y);\n"
- " v_texcoords[1].zw = texcoord + vec2(-step.x, -step.y);\n");
- fragment_program.append(
- " gl_FragColor = (\n"
- " texture2D(s_texture, v_texcoords[0].xy) +\n"
- " texture2D(s_texture, v_texcoords[0].zw) +\n"
- " texture2D(s_texture, v_texcoords[1].xy) +\n"
- " texture2D(s_texture, v_texcoords[1].zw)) / 4.0;\n");
- break;
-
- case SHADER_BICUBIC_HALF_1D:
- // This scales down texture by exactly half in one dimension.
- // directions in one pass. We use bilinear lookup to reduce
- // the number of texture reads from 8 to 4
- shared_variables.append(
- "const float CenterDist = 99.0 / 140.0;\n"
- "const float LobeDist = 11.0 / 4.0;\n"
- "const float CenterWeight = 35.0 / 64.0;\n"
- "const float LobeWeight = -3.0 / 64.0;\n"
- "varying vec4 v_texcoords[2];\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 src_pixelsize;\n");
- vertex_program.append(
- " vec2 step = src_subrect.zw * scaling_vector / src_pixelsize;\n"
- " v_texcoords[0].xy = texcoord - LobeDist * step;\n"
- " v_texcoords[0].zw = texcoord - CenterDist * step;\n"
- " v_texcoords[1].xy = texcoord + CenterDist * step;\n"
- " v_texcoords[1].zw = texcoord + LobeDist * step;\n");
- fragment_program.append(
- " gl_FragColor = \n"
- // Lobe pixels
- " (texture2D(s_texture, v_texcoords[0].xy) +\n"
- " texture2D(s_texture, v_texcoords[1].zw)) *\n"
- " LobeWeight +\n"
- // Center pixels
- " (texture2D(s_texture, v_texcoords[0].zw) +\n"
- " texture2D(s_texture, v_texcoords[1].xy)) *\n"
- " CenterWeight;\n");
- break;
-
- case SHADER_BICUBIC_UPSCALE:
- // When scaling up, we need 4 texture reads, but we can
- // save some instructions because will know in which range of
- // the bicubic function each call call to the bicubic function
- // will be in.
- // Also, when sampling the bicubic function like this, the sum
- // is always exactly one, so we can skip normalization as well.
- shared_variables.append("varying vec2 v_texcoord;\n");
- vertex_program.append(" v_texcoord = texcoord;\n");
- fragment_header.append(
- "uniform vec2 src_pixelsize;\n"
- "uniform vec2 scaling_vector;\n"
- "const float a = -0.5;\n"
- // This function is equivialent to calling the bicubic
- // function with x-1, x, 1-x and 2-x
- // (assuming 0 <= x < 1)
- "vec4 filt4(float x) {\n"
- " return vec4(x * x * x, x * x, x, 1) *\n"
- " mat4( a, -2.0 * a, a, 0.0,\n"
- " a + 2.0, -a - 3.0, 0.0, 1.0,\n"
- " -a - 2.0, 3.0 + 2.0 * a, -a, 0.0,\n"
- " -a, a, 0.0, 0.0);\n"
- "}\n"
- "mat4 pixels_x(vec2 pos, vec2 step) {\n"
- " return mat4(\n"
- " texture2D(s_texture, pos - step),\n"
- " texture2D(s_texture, pos),\n"
- " texture2D(s_texture, pos + step),\n"
- " texture2D(s_texture, pos + step * 2.0));\n"
- "}\n");
- fragment_program.append(
- " vec2 pixel_pos = v_texcoord * src_pixelsize - \n"
- " scaling_vector / 2.0;\n"
- " float frac = fract(dot(pixel_pos, scaling_vector));\n"
- " vec2 base = (floor(pixel_pos) + vec2(0.5)) / src_pixelsize;\n"
- " vec2 step = scaling_vector / src_pixelsize;\n"
- " gl_FragColor = pixels_x(base, step) * filt4(frac);\n");
- break;
-
- case SHADER_PLANAR:
- // Converts four RGBA pixels into one pixel. Each RGBA
- // pixel will be dot-multiplied with the color weights and
- // then placed into a component of the output. This is used to
- // convert RGBA textures into Y, U and V textures. We do this
- // because single-component textures are not renderable on all
- // architectures.
- shared_variables.append("varying vec4 v_texcoords[2];\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 4.0;\n"
- " v_texcoords[0].xy = texcoord - step * 1.5;\n"
- " v_texcoords[0].zw = texcoord - step * 0.5;\n"
- " v_texcoords[1].xy = texcoord + step * 0.5;\n"
- " v_texcoords[1].zw = texcoord + step * 1.5;\n");
- fragment_header.append("uniform vec4 color_weights;\n");
- fragment_program.append(
- " gl_FragColor = color_weights * mat4(\n"
- " vec4(texture2D(s_texture, v_texcoords[0].xy).rgb, 1.0),\n"
- " vec4(texture2D(s_texture, v_texcoords[0].zw).rgb, 1.0),\n"
- " vec4(texture2D(s_texture, v_texcoords[1].xy).rgb, 1.0),\n"
- " vec4(texture2D(s_texture, v_texcoords[1].zw).rgb, 1.0));\n");
- break;
-
- case SHADER_YUV_MRT_PASS1:
- // RGB24 to YV12 in two passes; writing two 8888 targets each pass.
- //
- // YV12 is full-resolution luma and half-resolution blue/red chroma.
- //
- // (original)
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // RGBX RGBX RGBX RGBX RGBX RGBX RGBX RGBX
- // |
- // | (y plane) (temporary)
- // | YYYY YYYY UUVV UUVV
- // +--> { YYYY YYYY + UUVV UUVV }
- // YYYY YYYY UUVV UUVV
- // First YYYY YYYY UUVV UUVV
- // pass YYYY YYYY UUVV UUVV
- // YYYY YYYY UUVV UUVV
- // |
- // | (u plane) (v plane)
- // Second | UUUU VVVV
- // pass +--> { UUUU + VVVV }
- // UUUU VVVV
- //
- shared_variables.append("varying vec4 v_texcoords[2];\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 4.0;\n"
- " v_texcoords[0].xy = texcoord - step * 1.5;\n"
- " v_texcoords[0].zw = texcoord - step * 0.5;\n"
- " v_texcoords[1].xy = texcoord + step * 0.5;\n"
- " v_texcoords[1].zw = texcoord + step * 1.5;\n");
- fragment_directives.append("#extension GL_EXT_draw_buffers : enable\n");
- fragment_header.append(
- "const vec3 kRGBtoY = vec3(0.257, 0.504, 0.098);\n"
- "const float kYBias = 0.0625;\n"
- // Divide U and V by two to compensate for averaging below.
- "const vec3 kRGBtoU = vec3(-0.148, -0.291, 0.439) / 2.0;\n"
- "const vec3 kRGBtoV = vec3(0.439, -0.368, -0.071) / 2.0;\n"
- "const float kUVBias = 0.5;\n");
- fragment_program.append(
- " vec3 pixel1 = texture2D(s_texture, v_texcoords[0].xy).rgb;\n"
- " vec3 pixel2 = texture2D(s_texture, v_texcoords[0].zw).rgb;\n"
- " vec3 pixel3 = texture2D(s_texture, v_texcoords[1].xy).rgb;\n"
- " vec3 pixel4 = texture2D(s_texture, v_texcoords[1].zw).rgb;\n"
- " vec3 pixel12 = pixel1 + pixel2;\n"
- " vec3 pixel34 = pixel3 + pixel4;\n"
- " gl_FragData[0] = vec4(dot(pixel1, kRGBtoY),\n"
- " dot(pixel2, kRGBtoY),\n"
- " dot(pixel3, kRGBtoY),\n"
- " dot(pixel4, kRGBtoY)) + kYBias;\n"
- " gl_FragData[1] = vec4(dot(pixel12, kRGBtoU),\n"
- " dot(pixel34, kRGBtoU),\n"
- " dot(pixel12, kRGBtoV),\n"
- " dot(pixel34, kRGBtoV)) + kUVBias;\n");
- break;
-
- case SHADER_YUV_MRT_PASS2:
- // We're just sampling two pixels and unswizzling them. There's
- // no need to do vertical scaling with math, since bilinear
- // interpolation in the sampler takes care of that.
- shared_variables.append("varying vec4 v_texcoords;\n");
- vertex_header.append(
- "uniform vec2 scaling_vector;\n"
- "uniform vec2 dst_pixelsize;\n");
- vertex_program.append(
- " vec2 step = scaling_vector * src_subrect.zw / dst_pixelsize;\n"
- " step /= 2.0;\n"
- " v_texcoords.xy = texcoord - step * 0.5;\n"
- " v_texcoords.zw = texcoord + step * 0.5;\n");
- fragment_directives.append("#extension GL_EXT_draw_buffers : enable\n");
- fragment_program.append(
- " vec4 lo_uuvv = texture2D(s_texture, v_texcoords.xy);\n"
- " vec4 hi_uuvv = texture2D(s_texture, v_texcoords.zw);\n"
- " gl_FragData[0] = vec4(lo_uuvv.rg, hi_uuvv.rg);\n"
- " gl_FragData[1] = vec4(lo_uuvv.ba, hi_uuvv.ba);\n");
- break;
- }
- if (swizzle) {
- switch (type) {
- case SHADER_YUV_MRT_PASS1:
- fragment_program.append(" gl_FragData[0] = gl_FragData[0].bgra;\n");
- break;
- case SHADER_YUV_MRT_PASS2:
- fragment_program.append(" gl_FragData[0] = gl_FragData[0].bgra;\n");
- fragment_program.append(" gl_FragData[1] = gl_FragData[1].bgra;\n");
- break;
- default:
- fragment_program.append(" gl_FragColor = gl_FragColor.bgra;\n");
- break;
- }
- }
-
- vertex_program = vertex_header + shared_variables + "void main() {\n" +
- vertex_program + "}\n";
-
- fragment_program = fragment_directives + fragment_header +
- shared_variables + "void main() {\n" + fragment_program +
- "}\n";
-
- cache_entry->Setup(vertex_program.c_str(), fragment_program.c_str());
- }
- return cache_entry;
-}
-
-void ShaderProgram::Setup(const GLchar* vertex_shader_text,
- const GLchar* fragment_shader_text) {
- // Shaders to map the source texture to |dst_texture_|.
- GLuint vertex_shader =
- helper_->CompileShaderFromSource(vertex_shader_text, GL_VERTEX_SHADER);
- if (vertex_shader == 0)
- return;
-
- gl_->AttachShader(program_, vertex_shader);
- gl_->DeleteShader(vertex_shader);
-
- GLuint fragment_shader = helper_->CompileShaderFromSource(
- fragment_shader_text, GL_FRAGMENT_SHADER);
- if (fragment_shader == 0)
- return;
- gl_->AttachShader(program_, fragment_shader);
- gl_->DeleteShader(fragment_shader);
-
- gl_->LinkProgram(program_);
-
- GLint link_status = 0;
- gl_->GetProgramiv(program_, GL_LINK_STATUS, &link_status);
- if (!link_status)
- return;
-
- position_location_ = gl_->GetAttribLocation(program_, "a_position");
- texcoord_location_ = gl_->GetAttribLocation(program_, "a_texcoord");
- texture_location_ = gl_->GetUniformLocation(program_, "s_texture");
- src_subrect_location_ = gl_->GetUniformLocation(program_, "src_subrect");
- src_pixelsize_location_ = gl_->GetUniformLocation(program_, "src_pixelsize");
- dst_pixelsize_location_ = gl_->GetUniformLocation(program_, "dst_pixelsize");
- scaling_vector_location_ =
- gl_->GetUniformLocation(program_, "scaling_vector");
- color_weights_location_ = gl_->GetUniformLocation(program_, "color_weights");
- // The only reason fetching these attribute locations should fail is
- // if the context was spontaneously lost (i.e., because the GPU
- // process crashed, perhaps deliberately for testing).
- DCHECK(Initialized() || gl_->GetGraphicsResetStatusKHR() != GL_NO_ERROR);
-}
-
-void ShaderProgram::UseProgram(const gfx::Size& src_size,
- const gfx::Rect& src_subrect,
- const gfx::Size& dst_size,
- bool scale_x,
- bool flip_y,
- GLfloat color_weights[4]) {
- gl_->UseProgram(program_);
-
- // OpenGL defines the last parameter to VertexAttribPointer as type
- // "const GLvoid*" even though it is actually an offset into the buffer
- // object's data store and not a pointer to the client's address space.
- const void* offsets[2] = {0,
- reinterpret_cast<const void*>(2 * sizeof(GLfloat))};
-
- gl_->VertexAttribPointer(position_location_, 2, GL_FLOAT, GL_FALSE,
- 4 * sizeof(GLfloat), offsets[0]);
- gl_->EnableVertexAttribArray(position_location_);
-
- gl_->VertexAttribPointer(texcoord_location_, 2, GL_FLOAT, GL_FALSE,
- 4 * sizeof(GLfloat), offsets[1]);
- gl_->EnableVertexAttribArray(texcoord_location_);
-
- gl_->Uniform1i(texture_location_, 0);
-
- // Convert |src_subrect| to texture coordinates.
- GLfloat src_subrect_texcoord[] = {
- static_cast<float>(src_subrect.x()) / src_size.width(),
- static_cast<float>(src_subrect.y()) / src_size.height(),
- static_cast<float>(src_subrect.width()) / src_size.width(),
- static_cast<float>(src_subrect.height()) / src_size.height(),
- };
- if (flip_y) {
- src_subrect_texcoord[1] += src_subrect_texcoord[3];
- src_subrect_texcoord[3] *= -1.0;
- }
- gl_->Uniform4fv(src_subrect_location_, 1, src_subrect_texcoord);
-
- gl_->Uniform2f(src_pixelsize_location_, src_size.width(), src_size.height());
- gl_->Uniform2f(dst_pixelsize_location_, static_cast<float>(dst_size.width()),
- static_cast<float>(dst_size.height()));
-
- gl_->Uniform2f(scaling_vector_location_, scale_x ? 1.0 : 0.0,
- scale_x ? 0.0 : 1.0);
- gl_->Uniform4fv(color_weights_location_, 1, color_weights);
-}
-
-} // namespace display_compositor
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