We started redesigning GpuMemoryBuffer interface to handle multiple buffers [0].

[0] https://codereview.chromium.org/1024113003/#ps200001

In this CL:

- I added a new format gfx::GpuMemoryBuffer::YUV_420
- Implemented helper functions to use with it on GpuMemoryBufferImpl.
- I added support in GpuMemoryBufferImplSharedMemory and GpuMemoryBufferFactorySharedMemory
- I added { gfx::GpuMemoryBuffer::YUV_420, gfx::GpuMemoryBuffer::MAP } as a supported config for testing
- I added support for multi plane in test implementations: test_gpu_memory_buffer_manager, gl_manager, gpu_memory_buffer_impl_unittest

The future steps are:
- Add a new GL_* internalformat corresponding to YUV_420
- Implement support for YUV_420 in GpuMemoryBufferFactoryOzoneNativeBuffer, GLImageLinuxDMABuffer and SurfaceFactoryOzone
- Expose file descriptors for gfx::GpuMemoryBuffer::YUV_420 via Map() or GpuMemoryBufferHandle struct
  Check usage of gbm_bo_get_fd() at the lowest gbmbuffer level
- Add support in GLImageSharedMemory and GLImageMemory through Bind functions
- Look for possible use cases of multiple buffers on Android, Mac, and Win platforms

BUG=439520
TEST=content_unittests  --gtest_filter=GpuMemoryBufferImplTests.*
content_unittests  --gtest_filter=GpuMemoryBufferFactoryTest.*
gl_tests --gtest_filter=GpuMemoryBufferTest*

Review URL: https://codereview.chromium.org/1062853002

Cr-Commit-Position: refs/heads/master@{#324190}

3 files changed, 75 insertions, 5 deletions

diff --git a/gpu/command_buffer/service/image_factory.cc b/gpu/command_buffer/service/image_factory.cc
index a80d17c..f09cfb8 100644
--- a/gpu/command_buffer/service/image_factory.cc
+++ b/gpu/command_buffer/service/image_factory.cc
@@ -80,6 +80,7 @@ bool ImageFactory::IsGpuMemoryBufferFormatSupported(
       return capabilities.texture_format_etc1;
     case gfx::GpuMemoryBuffer::RGBA_8888:
     case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::YUV_420:
       return true;
   }
 
@@ -103,6 +104,7 @@ bool ImageFactory::IsImageSizeValidForGpuMemoryBufferFormat(
     case gfx::GpuMemoryBuffer::RGBA_8888:
     case gfx::GpuMemoryBuffer::BGRA_8888:
     case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::YUV_420:
       return true;
   }
 
diff --git a/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc b/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
index 052bd3d..9368da5 100644
--- a/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
+++ b/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
@@ -98,6 +98,7 @@ std::vector<uint8> GetTexturePixel(const gfx::GpuMemoryBuffer::Format format) {
     case gfx::GpuMemoryBuffer::DXT5:
     case gfx::GpuMemoryBuffer::ETC1:
     case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::YUV_420:
       NOTREACHED();
       return std::vector<uint8>();
   }
@@ -123,6 +124,7 @@ std::vector<uint8> GetFramebufferPixel(
     case gfx::GpuMemoryBuffer::DXT5:
     case gfx::GpuMemoryBuffer::ETC1:
     case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::YUV_420:
       NOTREACHED();
       return std::vector<uint8>();
   }
@@ -143,6 +145,7 @@ GLenum InternalFormat(gfx::GpuMemoryBuffer::Format format) {
     case gfx::GpuMemoryBuffer::DXT5:
     case gfx::GpuMemoryBuffer::ETC1:
     case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::YUV_420:
       NOTREACHED();
       return 0;
   }
diff --git a/gpu/command_buffer/tests/gl_manager.cc b/gpu/command_buffer/tests/gl_manager.cc
index 67bdbb8..3a3d7e9 100644
--- a/gpu/command_buffer/tests/gl_manager.cc
+++ b/gpu/command_buffer/tests/gl_manager.cc
@@ -38,28 +38,85 @@
 namespace gpu {
 namespace {
 
-size_t StrideInBytes(size_t width, gfx::GpuMemoryBuffer::Format format) {
+size_t NumberOfPlanesForGpuMemoryBufferFormat(
+    gfx::GpuMemoryBuffer::Format format) {
+  switch (format) {
+    case gfx::GpuMemoryBuffer::Format::ATC:
+    case gfx::GpuMemoryBuffer::Format::ATCIA:
+    case gfx::GpuMemoryBuffer::Format::DXT1:
+    case gfx::GpuMemoryBuffer::Format::DXT5:
+    case gfx::GpuMemoryBuffer::Format::ETC1:
+    case gfx::GpuMemoryBuffer::Format::RGBA_8888:
+    case gfx::GpuMemoryBuffer::Format::RGBX_8888:
+    case gfx::GpuMemoryBuffer::Format::BGRA_8888:
+      return 1;
+    case gfx::GpuMemoryBuffer::Format::YUV_420:
+      return 3;
+  }
+  NOTREACHED();
+  return 0;
+}
+
+size_t SubsamplingFactor(gfx::GpuMemoryBuffer::Format format, int plane) {
   switch (format) {
+    case gfx::GpuMemoryBuffer::ATC:
     case gfx::GpuMemoryBuffer::ATCIA:
+    case gfx::GpuMemoryBuffer::DXT1:
     case gfx::GpuMemoryBuffer::DXT5:
+    case gfx::GpuMemoryBuffer::ETC1:
+    case gfx::GpuMemoryBuffer::RGBA_8888:
+    case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::BGRA_8888:
+      return 1;
+    case gfx::GpuMemoryBuffer::YUV_420: {
+      static size_t factor[] = {1, 2, 2};
+      DCHECK_LT(static_cast<size_t>(plane), arraysize(factor));
+      return factor[plane];
+    }
+  }
+  NOTREACHED();
+  return 0;
+}
+
+size_t StrideInBytes(size_t width,
+                     gfx::GpuMemoryBuffer::Format format,
+                     int plane) {
+  switch (format) {
+    case gfx::GpuMemoryBuffer::ATCIA:
+    case gfx::GpuMemoryBuffer::DXT5:
+      DCHECK_EQ(plane, 0);
       return width;
     case gfx::GpuMemoryBuffer::ATC:
     case gfx::GpuMemoryBuffer::DXT1:
     case gfx::GpuMemoryBuffer::ETC1:
+      DCHECK_EQ(plane, 0);
       DCHECK_EQ(width % 2, 0U);
       return width / 2;
     case gfx::GpuMemoryBuffer::RGBA_8888:
     case gfx::GpuMemoryBuffer::BGRA_8888:
+      DCHECK_EQ(plane, 0);
       return width * 4;
     case gfx::GpuMemoryBuffer::RGBX_8888:
       NOTREACHED();
       return 0;
+    case gfx::GpuMemoryBuffer::YUV_420:
+      return width / SubsamplingFactor(format, plane);
   }
 
   NOTREACHED();
   return 0;
 }
 
+size_t BufferSizeInBytes(const gfx::Size& size,
+                         gfx::GpuMemoryBuffer::Format format) {
+  size_t size_in_bytes = 0u;
+  for (size_t i = 0; i < NumberOfPlanesForGpuMemoryBufferFormat(format); ++i) {
+    size_in_bytes += StrideInBytes(size.width(), format, i) *
+                     (size.height() / SubsamplingFactor(format, i));
+  }
+  return size_in_bytes;
+}
+
 class GpuMemoryBufferImpl : public gfx::GpuMemoryBuffer {
  public:
   GpuMemoryBufferImpl(base::RefCountedBytes* bytes,
@@ -73,15 +130,24 @@ class GpuMemoryBufferImpl : public gfx::GpuMemoryBuffer {
 
   // Overridden from gfx::GpuMemoryBuffer:
   bool Map(void** data) override {
+    data[0] = &bytes_->data().front();
+    for (size_t i = 0; i < NumberOfPlanesForGpuMemoryBufferFormat(format_) - 1;
+         ++i) {
+      size_t offset = StrideInBytes(size_.width(), format_, i) *
+                      (size_.height() / SubsamplingFactor(format_, i));
+      data[i + 1] = reinterpret_cast<uint8*>(data[i]) + offset;
+    }
     mapped_ = true;
-    *data = &bytes_->data().front();
     return true;
   }
   void Unmap() override { mapped_ = false; }
   bool IsMapped() const override { return mapped_; }
   Format GetFormat() const override { return format_; }
   void GetStride(uint32* stride) const override {
-    *stride = StrideInBytes(size_.width(), format_);
+    for (size_t i = 0; i < NumberOfPlanesForGpuMemoryBufferFormat(format_);
+         ++i) {
+      stride[i] = StrideInBytes(size_.width(), format_, i);
+    }
   }
   gfx::GpuMemoryBufferHandle GetHandle() const override {
     NOTREACHED();
@@ -143,8 +209,7 @@ GLManager::~GLManager() {
 scoped_ptr<gfx::GpuMemoryBuffer> GLManager::CreateGpuMemoryBuffer(
     const gfx::Size& size,
     gfx::GpuMemoryBuffer::Format format) {
-  std::vector<unsigned char> data(
-      StrideInBytes(size.width(), format) * size.height(), 0);
+  std::vector<unsigned char> data(BufferSizeInBytes(size, format), 0);
   scoped_refptr<base::RefCountedBytes> bytes(new base::RefCountedBytes(data));
   return make_scoped_ptr<gfx::GpuMemoryBuffer>(
       new GpuMemoryBufferImpl(bytes.get(), size, format));