gpu: Add YCbCr 420v extension.

ui/gl/gl_image_io_surface.mm

Index: ui/gl/gl_image_io_surface.mm
diff --git a/ui/gl/gl_image_io_surface.mm b/ui/gl/gl_image_io_surface.mm
index dfd8df9e827ae7dded0dbe94685d8fc44e6f1800..c276327eb5ce080b5882e29d07f8e6601532c734 100644
--- a/ui/gl/gl_image_io_surface.mm
+++ b/ui/gl/gl_image_io_surface.mm
@@ -8,11 +8,14 @@
 
 #include "base/lazy_instance.h"
 #include "base/mac/foundation_util.h"
+#include "base/strings/stringize_macros.h"
 #include "base/trace_event/memory_allocator_dump.h"
 #include "base/trace_event/memory_dump_manager.h"
 #include "base/trace_event/process_memory_dump.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
+#include "ui/gl/gl_helper.h"
+#include "ui/gl/scoped_binders.h"
 
 // Note that this must be included after gl_bindings.h to avoid conflicts.
 #include <OpenGL/CGLIOSurface.h>
@@ -26,11 +29,42 @@ namespace {
 using WidgetToLayerMap = std::map<gfx::AcceleratedWidget, CALayer*>;
 base::LazyInstance<WidgetToLayerMap> g_widget_to_layer_map;
 
+// clang-format off
+const char kVertexShader[] =
+STRINGIZE(
+  attribute vec2 a_position;
+  uniform vec2 a_texScale;
+  varying vec2 v_texCoord;
+  void main() {
+    gl_Position = vec4(a_position.x, a_position.y, 0.0, 1.0);
+    v_texCoord = (a_position + vec2(1.0, 1.0)) * 0.5 * a_texScale;
+  }
+);
+
+const char kFragmentShader[] =
+STRINGIZE(
+  uniform sampler2DRect a_y_texture;
+  uniform sampler2DRect a_uv_texture;
+  varying vec2 v_texCoord;
+  void main() {
+    vec3 yuv_adj = vec3(-0.0625, -0.5, -0.5);
+    mat3 yuv_matrix = mat3(vec3(1.164, 1.164, 1.164),
+                           vec3(0.0, -.391, 2.018),
+                           vec3(1.596, -.813, 0.0));
+    vec3 yuv = vec3(
+        texture2DRect(a_y_texture, v_texCoord).r,
+        texture2DRect(a_uv_texture, v_texCoord * 0.5).rg);
+    gl_FragColor = vec4(yuv_matrix * (yuv + yuv_adj), 1.0);
+  }
+);
+// clang-format on
+
 bool ValidInternalFormat(unsigned internalformat) {
   switch (internalformat) {
     case GL_RED:
     case GL_BGRA_EXT:
     case GL_RGB:
+    case GL_RGB_YCBCR_420V_CHROMIUM:
     case GL_RGB_YCBCR_422_CHROMIUM:
     case GL_RGBA:
       return true;
@@ -66,13 +100,14 @@ bool ValidFormat(BufferFormat format) {
 GLenum TextureFormat(BufferFormat format) {
   switch (format) {
     case BufferFormat::R_8:
-    case BufferFormat::YUV_420_BIPLANAR:
       return GL_RED;
     case BufferFormat::BGRA_8888:
     case BufferFormat::RGBA_8888:
       return GL_RGBA;
     case BufferFormat::UYVY_422:
       return GL_RGB;
+    case BufferFormat::YUV_420_BIPLANAR:
+      return GL_RGB_YCBCR_420V_CHROMIUM;
     case BufferFormat::ATC:
     case BufferFormat::ATCIA:
     case BufferFormat::DXT1:
@@ -93,14 +128,12 @@ GLenum TextureFormat(BufferFormat format) {
 GLenum DataFormat(BufferFormat format) {
   switch (format) {
     case BufferFormat::R_8:
-    case BufferFormat::YUV_420_BIPLANAR:
       return GL_RED;
     case BufferFormat::BGRA_8888:
     case BufferFormat::RGBA_8888:
       return GL_BGRA;
     case BufferFormat::UYVY_422:
       return GL_YCBCR_422_APPLE;
-      break;
     case BufferFormat::ATC:
     case BufferFormat::ATCIA:
     case BufferFormat::DXT1:
@@ -110,6 +143,7 @@ GLenum DataFormat(BufferFormat format) {
     case BufferFormat::RGBX_8888:
     case BufferFormat::BGRX_8888:
     case BufferFormat::YUV_420:
+    case BufferFormat::YUV_420_BIPLANAR:
       NOTREACHED();
       return 0;
   }
@@ -121,7 +155,6 @@ GLenum DataFormat(BufferFormat format) {
 GLenum DataType(BufferFormat format) {
   switch (format) {
     case BufferFormat::R_8:
-    case BufferFormat::YUV_420_BIPLANAR:
       return GL_UNSIGNED_BYTE;
     case BufferFormat::BGRA_8888:
     case BufferFormat::RGBA_8888:
@@ -138,6 +171,7 @@ GLenum DataType(BufferFormat format) {
     case BufferFormat::RGBX_8888:
     case BufferFormat::BGRX_8888:
     case BufferFormat::YUV_420:
+    case BufferFormat::YUV_420_BIPLANAR:
       NOTREACHED();
       return 0;
   }
@@ -146,6 +180,15 @@ GLenum DataType(BufferFormat format) {
   return 0;
 }
 
+GLuint SetupVertexBuffer() {
+  GLuint vertex_buffer = 0;
+  glGenBuffersARB(1, &vertex_buffer);
+  gfx::ScopedBufferBinder buffer_binder(GL_ARRAY_BUFFER, vertex_buffer);
+  GLfloat data[] = {-1.f, -1.f, 1.f, -1.f, -1.f, 1.f, 1.f, 1.f};
+  glBufferData(GL_ARRAY_BUFFER, sizeof(data), data, GL_STATIC_DRAW);
+  return vertex_buffer;
+}
+
 }  // namespace
 
 GLImageIOSurface::GLImageIOSurface(const gfx::Size& size,
@@ -183,6 +226,14 @@ bool GLImageIOSurface::Initialize(IOSurfaceRef io_surface,
 
 void GLImageIOSurface::Destroy(bool have_context) {
   DCHECK(thread_checker_.CalledOnValidThread());
+  if (have_context && framebuffer_) {
+    glDeleteProgram(program_);
+    glDeleteShader(vertex_shader_);
+    glDeleteShader(fragment_shader_);
+    glDeleteBuffersARB(1, &vertex_buffer_);
+    glDeleteFramebuffersEXT(1, &framebuffer_);
+    glDeleteTextures(2, yuv_textures_);
+  }
   io_surface_.reset();
 }
 
@@ -190,10 +241,19 @@ gfx::Size GLImageIOSurface::GetSize() {
   return size_;
 }
 
-unsigned GLImageIOSurface::GetInternalFormat() { return internalformat_; }
+unsigned GLImageIOSurface::GetInternalFormat() {
+  return internalformat_;
+}
 
 bool GLImageIOSurface::BindTexImage(unsigned target) {
   DCHECK(thread_checker_.CalledOnValidThread());
+
+  // YUV_420_BIPLANAR is not supported by BindTexImage.
+  // CopyTexImage is supported by this format as that performs conversion to RGB
+  // as part of the copy operation.
+  if (format_ == BufferFormat::YUV_420_BIPLANAR)
+    return false;
+
   if (target != GL_TEXTURE_RECTANGLE_ARB) {
     // This might be supported in the future. For now, perform strict
     // validation so we know what's going on.
@@ -218,7 +278,107 @@ bool GLImageIOSurface::BindTexImage(unsigned target) {
 }
 
 bool GLImageIOSurface::CopyTexImage(unsigned target) {
-  return false;
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  if (format_ != BufferFormat::YUV_420_BIPLANAR)
+    return false;
+
+  if (target != GL_TEXTURE_2D) {
+    LOG(ERROR) << "YUV_420_BIPLANAR requires TEXTURE_2D target";
+    return false;
+  }
+
+  if (!framebuffer_) {
+    glGenFramebuffersEXT(1, &framebuffer_);
+    vertex_buffer_ = SetupVertexBuffer();
+    vertex_shader_ = gfx::GLHelper::LoadShader(GL_VERTEX_SHADER, kVertexShader);
+    fragment_shader_ =
+        gfx::GLHelper::LoadShader(GL_FRAGMENT_SHADER, kFragmentShader);
+    program_ = gfx::GLHelper::SetupProgram(vertex_shader_, fragment_shader_);
+    gfx::ScopedUseProgram use_program(program_);
+
+    size_location_ = glGetUniformLocation(program_, "a_texScale");
+    DCHECK_NE(-1, size_location_);
+    int y_sampler_location = glGetUniformLocation(program_, "a_y_texture");
+    DCHECK_NE(-1, y_sampler_location);
+    int uv_sampler_location = glGetUniformLocation(program_, "a_uv_texture");
+    DCHECK_NE(-1, uv_sampler_location);
+
+    glUniform1i(y_sampler_location, 0);
+    glUniform1i(uv_sampler_location, 1);
+
+    glGenTextures(2, yuv_textures_);
+    DCHECK(yuv_textures_[0]);
+    DCHECK(yuv_textures_[1]);
+  }
+
+  CGLContextObj cgl_context =
+      static_cast<CGLContextObj>(gfx::GLContext::GetCurrent()->GetHandle());
+
+  GLint target_texture = 0;
+  glGetIntegerv(GL_TEXTURE_BINDING_2D, &target_texture);
+  DCHECK(target_texture);
+  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, size_.width(), size_.height(), 0,
+               GL_RGB, GL_UNSIGNED_BYTE, nullptr);
+
+  CGLError cgl_error = kCGLNoError;
+  {
+    DCHECK(io_surface_);
+
+    gfx::ScopedActiveTexture active_texture0(GL_TEXTURE0);
+    gfx::ScopedTextureBinder texture_y_binder(GL_TEXTURE_RECTANGLE_ARB,
+                                              yuv_textures_[0]);
+    cgl_error = CGLTexImageIOSurface2D(
+        cgl_context, GL_TEXTURE_RECTANGLE_ARB, GL_RED, size_.width(),
+        size_.height(), GL_RED, GL_UNSIGNED_BYTE, io_surface_.get(), 0);
+    if (cgl_error != kCGLNoError) {
+      LOG(ERROR) << "Error in CGLTexImageIOSurface2D for the Y plane. "
+                 << cgl_error;
+      return false;
+    }
+    {
+      gfx::ScopedActiveTexture active_texture1(GL_TEXTURE1);
+      gfx::ScopedTextureBinder texture_uv_binder(GL_TEXTURE_RECTANGLE_ARB,
+                                                 yuv_textures_[1]);
+      cgl_error = CGLTexImageIOSurface2D(
+          cgl_context, GL_TEXTURE_RECTANGLE_ARB, GL_RG, size_.width() / 2,
+          size_.height() / 2, GL_RG, GL_UNSIGNED_BYTE, io_surface_.get(), 1);
+      if (cgl_error != kCGLNoError) {
+        LOG(ERROR) << "Error in CGLTexImageIOSurface2D for the UV plane. "
+                   << cgl_error;
+        return false;
+      }
+
+      gfx::ScopedFrameBufferBinder framebuffer_binder(framebuffer_);
+      gfx::ScopedViewport viewport(0, 0, size_.width(), size_.height());
+      glViewport(0, 0, size_.width(), size_.height());
+      glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                                GL_TEXTURE_2D, target_texture, 0);
+      DCHECK_EQ(static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE),
+                glCheckFramebufferStatusEXT(GL_FRAMEBUFFER));
+
+      gfx::ScopedUseProgram use_program(program_);
+      glUniform2f(size_location_, size_.width(), size_.height());
+
+      // TODO(dcastagna): Extract and share the following code to draw a quad.
+      gfx::ScopedBufferBinder buffer_binder(GL_ARRAY_BUFFER, vertex_buffer_);
+      gfx::ScopedVertexAttribArray vertex_attrib_array(0, 2, GL_FLOAT, GL_FALSE,
+                                                       sizeof(GLfloat) * 2, 0);
+      gfx::ScopedCapability disable_blending(GL_BLEND, GL_FALSE);
+      gfx::ScopedCapability disable_culling(GL_CULL_FACE, GL_FALSE);
+      gfx::ScopedCapability disable_dithering(GL_DITHER, GL_FALSE);
+      gfx::ScopedCapability disable_depth_test(GL_DEPTH_TEST, GL_FALSE);
+      gfx::ScopedCapability disable_scissor_test(GL_SCISSOR_TEST, GL_FALSE);
+      gfx::ScopedColorMask color_mask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+
+      glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+
+      // Detach the output texture from the fbo.
+      glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                                GL_TEXTURE_2D, 0, 0);
+    }
+  }
+  return true;
 }
 
 bool GLImageIOSurface::CopyTexSubImage(unsigned target,
@@ -268,4 +428,10 @@ void GLImageIOSurface::SetLayerForWidget(gfx::AcceleratedWidget widget,
     g_widget_to_layer_map.Pointer()->erase(widget);
 }
 
-}  // namespace gfx
+// static
+unsigned GLImageIOSurface::GetInternalFormatForTesting(
+    gfx::BufferFormat format) {
+  DCHECK(ValidFormat(format));
+  return TextureFormat(format);
+}
+}  // namespace gl