components/bitmap_uploader/bitmap_uploader.cc

// Copyright 2015 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/bitmap_uploader/bitmap_uploader.h"

#include <stddef.h>
#include <utility>

#include "base/bind.h"
#include "base/callback.h"
#include "components/mus/public/cpp/gles2_context.h"
#include "components/mus/public/cpp/surfaces/surfaces_type_converters.h"
#include "components/mus/public/cpp/surfaces/surfaces_utils.h"
#include "components/mus/public/cpp/window.h"
#include "components/mus/public/cpp/window_surface.h"
#include "services/shell/public/cpp/connector.h"

namespace bitmap_uploader {
namespace {

const uint32_t g_transparent_color = 0x00000000;

}  // namespace

const char kBitmapUploaderForAcceleratedWidget[] =
    "__BITMAP_UPLOADER_ACCELERATED_WIDGET__";

BitmapUploader::BitmapUploader(mus::Window* window)
    : window_(window),
      color_(g_transparent_color),
      width_(0),
      height_(0),
      format_(BGRA),
      next_resource_id_(1u),
      id_namespace_(0u) {}

BitmapUploader::~BitmapUploader() {
}

void BitmapUploader::Init(shell::Connector* connector) {
  surface_ = window_->RequestSurface(mus::mojom::SurfaceType::DEFAULT);
  surface_->BindToThread();
  surface_->set_client(this);

  connector->ConnectToInterface("mojo:mus", &gpu_service_);
  mus::mojom::CommandBufferPtr command_buffer_ptr;
  gpu_service_->CreateOffscreenGLES2Context(GetProxy(&command_buffer_ptr));
  gles2_context_.reset(new mus::GLES2Context(std::vector<int32_t>(),
                                             std::move(command_buffer_ptr)));
  bool initialized = gles2_context_->Initialize();
  DCHECK(initialized);
}

// Sets the color which is RGBA.
void BitmapUploader::SetColor(uint32_t color) {
  if (color_ == color)
    return;
  color_ = color;
  if (surface_)
    Upload();
}

// Sets a bitmap.
void BitmapUploader::SetBitmap(int width,
                               int height,
                               std::unique_ptr<std::vector<unsigned char>> data,
                               Format format) {
  width_ = width;
  height_ = height;
  bitmap_ = std::move(data);
  format_ = format;
  if (surface_)
    Upload();
}

void BitmapUploader::Upload() {
  // If the |gpu_service_| has errored than we won't get far. Do nothing,
  // assuming we are in shutdown.
  if (gpu_service_.encountered_error())
    return;

  const gfx::Rect bounds(window_->bounds());
  mus::mojom::PassPtr pass = mojo::CreateDefaultPass(1, bounds);
  mus::mojom::CompositorFramePtr frame = mus::mojom::CompositorFrame::New();

  // TODO(rjkroege): Support device scale factor in PDF viewer
  mus::mojom::CompositorFrameMetadataPtr meta =
      mus::mojom::CompositorFrameMetadata::New();
  meta->device_scale_factor = 1.0f;
  frame->metadata = std::move(meta);

  frame->resources.resize(0u);

  pass->quads.resize(0u);
  pass->shared_quad_states.push_back(mojo::CreateDefaultSQS(bounds.size()));

  if (bitmap_.get()) {
    gpu::gles2::GLES2Interface* gl = gles2_context_->interface();
    gfx::Size bitmap_size(width_, height_);
    GLuint texture_id = BindTextureForSize(bitmap_size);
    gl->TexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bitmap_size.width(),
                      bitmap_size.height(), TextureFormat(), GL_UNSIGNED_BYTE,
                      &((*bitmap_)[0]));

    gpu::Mailbox mailbox;
    gl->GenMailboxCHROMIUM(mailbox.name);
    gl->ProduceTextureCHROMIUM(GL_TEXTURE_2D, mailbox.name);

    const GLuint64 fence_sync = gl->InsertFenceSyncCHROMIUM();
    gl->ShallowFlushCHROMIUM();

    gpu::SyncToken sync_token;
    gl->GenSyncTokenCHROMIUM(fence_sync, sync_token.GetData());

    cc::TransferableResource resource;
    resource.id = next_resource_id_++;
    resource_to_texture_id_map_[resource.id] = texture_id;
    resource.format = cc::ResourceFormat::RGBA_8888;
    resource.filter = GL_LINEAR;
    resource.size = bitmap_size;
    resource.mailbox_holder =
        gpu::MailboxHolder(mailbox, sync_token, GL_TEXTURE_2D);
    resource.read_lock_fences_enabled = false;
    resource.is_software = false;
    resource.is_overlay_candidate = false;

    mus::mojom::QuadPtr quad = mus::mojom::Quad::New();
    quad->material = mus::mojom::Material::TEXTURE_CONTENT;

    gfx::Size rect_size;
    if (width_ <= bounds.width() && height_ <= bounds.height()) {
      rect_size.SetSize(width_, height_);
    } else {
      // The source bitmap is larger than the viewport. Resize it while
      // maintaining the aspect ratio.
      float width_ratio = static_cast<float>(width_) / bounds.width();
      float height_ratio = static_cast<float>(height_) / bounds.height();
      if (width_ratio > height_ratio) {
        rect_size.SetSize(bounds.width(), height_ / width_ratio);
      } else {
        rect_size.SetSize(width_ / height_ratio, bounds.height());
      }
    }
    gfx::Rect rect(rect_size);
    quad->rect = rect;
    quad->opaque_rect = rect;
    quad->visible_rect = rect;
    quad->needs_blending = true;
    quad->shared_quad_state_index = 0u;

    mus::mojom::TextureQuadStatePtr texture_state =
        mus::mojom::TextureQuadState::New();
    texture_state->resource_id = resource.id;
    texture_state->premultiplied_alpha = true;
    texture_state->uv_top_left.SetPoint(0.f, 0.f);
    texture_state->uv_bottom_right.SetPoint(1.f, 1.f);
    texture_state->background_color = mus::mojom::Color::New();
    texture_state->background_color->rgba = g_transparent_color;
    for (int i = 0; i < 4; ++i)
      texture_state->vertex_opacity.push_back(1.f);
    texture_state->y_flipped = false;

    frame->resources.push_back(std::move(resource));
    quad->texture_quad_state = std::move(texture_state);
    pass->quads.push_back(std::move(quad));
  }

  if (color_ != g_transparent_color) {
    mus::mojom::QuadPtr quad = mus::mojom::Quad::New();
    quad->material = mus::mojom::Material::SOLID_COLOR;
    quad->rect = bounds;
    quad->visible_rect = bounds;
    quad->needs_blending = true;
    quad->shared_quad_state_index = 0u;

    mus::mojom::SolidColorQuadStatePtr color_state =
        mus::mojom::SolidColorQuadState::New();
    color_state->color = mus::mojom::Color::New();
    color_state->color->rgba = color_;
    color_state->force_anti_aliasing_off = false;

    quad->solid_color_quad_state = std::move(color_state);
    pass->quads.push_back(std::move(quad));
  }

  frame->passes.push_back(std::move(pass));

  // TODO(rjkroege, fsamuel): We should throttle frames.
  surface_->SubmitCompositorFrame(std::move(frame), mojo::Closure());
}

uint32_t BitmapUploader::BindTextureForSize(const gfx::Size& size) {
  gpu::gles2::GLES2Interface* gl = gles2_context_->interface();
  // TODO(jamesr): Recycle textures.
  GLuint texture = 0u;
  gl->GenTextures(1, &texture);
  gl->BindTexture(GL_TEXTURE_2D, texture);
  gl->TexImage2D(GL_TEXTURE_2D, 0, TextureFormat(), size.width(), size.height(),
                 0, TextureFormat(), GL_UNSIGNED_BYTE, 0);
  gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  return texture;
}

void BitmapUploader::SetIdNamespace(uint32_t id_namespace) {
  id_namespace_ = id_namespace;
  if (color_ != g_transparent_color || bitmap_.get())
    Upload();
}

void BitmapUploader::OnResourcesReturned(
    mus::WindowSurface* surface,
    mojo::Array<cc::ReturnedResource> resources) {
  gpu::gles2::GLES2Interface* gl = gles2_context_->interface();
  // TODO(jamesr): Recycle.
  for (size_t i = 0; i < resources.size(); ++i) {
    cc::ReturnedResource resource = std::move(resources[i]);
    DCHECK_EQ(1, resource.count);
    gl->WaitSyncTokenCHROMIUM(resource.sync_token.GetConstData());
    uint32_t texture_id = resource_to_texture_id_map_[resource.id];
    DCHECK_NE(0u, texture_id);
    resource_to_texture_id_map_.erase(resource.id);
    gl->DeleteTextures(1, &texture_id);
  }
}

}  // namespace bitmap_uploader