Make Android StreamTexture implement GLStreamTextureImage

content/common/gpu/stream_texture_android.cc

 // Copyright (c) 2013 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 "content/common/gpu/stream_texture_android.h"
 
 #include <string.h>
 
 #include "base/bind.h"
 #include "base/strings/stringize_macros.h"
@@ skipping 24 matching lines @@
   GLES2Decoder* decoder = owner_stub->decoder();
   TextureManager* texture_manager =
       decoder->GetContextGroup()->texture_manager();
   TextureRef* texture = texture_manager->GetTexture(client_texture_id);
 
   if (texture && (!texture->texture()->target() ||
                   texture->texture()->target() == GL_TEXTURE_EXTERNAL_OES)) {
 
     // TODO: Ideally a valid image id was returned to the client so that
     // it could then call glBindTexImage2D() for doing the following.
-    scoped_refptr<gl::GLImage> gl_image(
+    scoped_refptr<gpu::gles2::GLStreamTextureImage> gl_image(
         new StreamTexture(owner_stub, stream_id, texture->service_id()));
     gfx::Size size = gl_image->GetSize();
     texture_manager->SetTarget(texture, GL_TEXTURE_EXTERNAL_OES);
     texture_manager->SetLevelInfo(texture, GL_TEXTURE_EXTERNAL_OES, 0, GL_RGBA,
                                   size.width(), size.height(), 1, 0, GL_RGBA,
                                   GL_UNSIGNED_BYTE, gfx::Rect(size));
-    texture_manager->SetLevelImage(texture, GL_TEXTURE_EXTERNAL_OES, 0,
-                                   gl_image.get(),
-                                   gpu::gles2::Texture::UNBOUND);
+    texture_manager->SetLevelStreamTextureImage(
+        texture, GL_TEXTURE_EXTERNAL_OES, 0, gl_image.get(),
+        gpu::gles2::Texture::UNBOUND);
     return true;
   }
 
   return false;
 }
 
 StreamTexture::StreamTexture(GpuCommandBufferStub* owner_stub,
                              int32_t route_id,
                              uint32_t texture_id)
     : surface_texture_(gfx::SurfaceTexture::Create(texture_id)),
       size_(0, 0),
-      has_valid_frame_(false),
       has_pending_frame_(false),
       owner_stub_(owner_stub),
       route_id_(route_id),
       has_listener_(false),
       texture_id_(texture_id),
       framebuffer_(0),
       vertex_shader_(0),
       fragment_shader_(0),
       program_(0),
       vertex_buffer_(0),
       u_xform_location_(-1),
       weak_factory_(this) {
   owner_stub->AddDestructionObserver(this);
   memset(current_matrix_, 0, sizeof(current_matrix_));
   owner_stub->channel()->AddRoute(route_id, owner_stub->stream_id(), this);
   surface_texture_->SetFrameAvailableCallback(base::Bind(
       &StreamTexture::OnFrameAvailable, weak_factory_.GetWeakPtr()));
 }
 
 StreamTexture::~StreamTexture() {
   if (owner_stub_) {
     owner_stub_->RemoveDestructionObserver(this);
     owner_stub_->channel()->RemoveRoute(route_id_);
   }
 }
 
+// gpu::gles2::GLStreamTextureMatrix implementation
+void StreamTexture::GetTextureMatrix(float xform[16]) {
+  UpdateTexImage();

[no sievers, 2016/03/18 01:34:11]

Doesn't this blow up in Chrome without a |scoped_ptr<ui::ScopedMakeCurrent>
scoped_make_current(MakeStubCurrent())|? (And with virtual contexts disabled.)

SurfaceTexture doesn't allow calling UpdateTexImage(), see
GLConsumer::mEglContext checks.

So it would fail in the case where we call updateTexImage() from different
contexts which could be for example if we draw it in the browser vs. copying it
out in the renderer (webgl, canvas).

On a related note, it would be nice to avoid the context switch in the more
important case (browser context).

[Tobias Sargeant, 2016/03/18 10:30:13]

This is calling the UpdateTexImage below, which does the required context
switch, and also guards against calling surface_texture_->UpdateTexImage() more
than once per available frame.

I guess depending on where the surface texture is used from, we might end up
doing quite a bit of context switching. It seems we can't know ahead of time how
it will be used, but it could probably be optimized for the draw-only case.

+  surface_texture_->GetTransformMatrix(xform);
+}
+
 void StreamTexture::OnWillDestroyStub() {
   owner_stub_->RemoveDestructionObserver(this);
   owner_stub_->channel()->RemoveRoute(route_id_);
 
   if (framebuffer_) {
     scoped_ptr<ui::ScopedMakeCurrent> scoped_make_current(MakeStubCurrent());
 
     glDeleteProgram(program_);
     glDeleteShader(vertex_shader_);
     glDeleteShader(fragment_shader_);
@@ skipping 32 matching lines @@
 void StreamTexture::UpdateTexImage() {
   DCHECK(surface_texture_.get());
   DCHECK(owner_stub_);
 
   if (!has_pending_frame_) return;
 
   scoped_ptr<ui::ScopedMakeCurrent> scoped_make_current(MakeStubCurrent());
 
   surface_texture_->UpdateTexImage();
 
-  has_valid_frame_ = true;
   has_pending_frame_ = false;
 
-  float mtx[16];
-  surface_texture_->GetTransformMatrix(mtx);
-
-  if (memcmp(current_matrix_, mtx, sizeof(mtx)) != 0) {
-    memcpy(current_matrix_, mtx, sizeof(mtx));
-
-    if (has_listener_) {
-      GpuStreamTextureMsg_MatrixChanged_Params params;
-      memcpy(&params.m00, mtx, sizeof(mtx));
-      owner_stub_->channel()->Send(
-          new GpuStreamTextureMsg_MatrixChanged(route_id_, params));
-    }
-  }
-
   if (scoped_make_current.get()) {
     // UpdateTexImage() implies glBindTexture().
     // The cmd decoder takes care of restoring the binding for this GLImage as
     // far as the current context is concerned, but if we temporarily change
     // it, we have to keep the state intact in *that* context also.
     const gpu::gles2::ContextState* state =
         owner_stub_->decoder()->GetContextState();
     const gpu::gles2::TextureUnit& active_unit =
         state->texture_units[state->active_texture_unit];
     glBindTexture(GL_TEXTURE_EXTERNAL_OES,
                   active_unit.bound_texture_external_oes.get()
                       ? active_unit.bound_texture_external_oes->service_id()
                       : 0);
   }
 }
 
 bool StreamTexture::CopyTexImage(unsigned target) {
-  if (target == GL_TEXTURE_2D) {
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, size_.width(), size_.height(), 0,
-                 GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
-    return CopyTexSubImage(GL_TEXTURE_2D, gfx::Point(), gfx::Rect(size_));
-  }
-
   if (target != GL_TEXTURE_EXTERNAL_OES)
     return false;
 
   if (!owner_stub_ || !surface_texture_.get())
     return true;
 
   GLint texture_id;
   glGetIntegerv(GL_TEXTURE_BINDING_EXTERNAL_OES, &texture_id);
   DCHECK(texture_id);
 
   // The following code only works if we're being asked to copy into
   // |texture_id_|. Copying into a different texture is not supported.
   if (static_cast<unsigned>(texture_id) != texture_id_)
     return false;
 
   UpdateTexImage();
 
   TextureManager* texture_manager =
       owner_stub_->decoder()->GetContextGroup()->texture_manager();
   gpu::gles2::Texture* texture =
       texture_manager->GetTextureForServiceId(texture_id_);
   if (texture) {
     // By setting image state to UNBOUND instead of COPIED we ensure that
     // CopyTexImage() is called each time the surface texture is used for
     // drawing.
-    texture->SetLevelImage(GL_TEXTURE_EXTERNAL_OES, 0, this,
-                           gpu::gles2::Texture::UNBOUND);
+    texture->SetLevelStreamTextureImage(GL_TEXTURE_EXTERNAL_OES, 0, this,
+                                        gpu::gles2::Texture::UNBOUND);
   }
 
   return true;
 }
 
 void StreamTexture::OnFrameAvailable() {
   has_pending_frame_ = true;
   if (has_listener_ && owner_stub_) {
     owner_stub_->channel()->Send(
         new GpuStreamTextureMsg_FrameAvailable(route_id_));
@@ skipping 41 matching lines @@
   return false;
 }
 
 void StreamTexture::ReleaseTexImage(unsigned target) {
   NOTREACHED();
 }
 
 bool StreamTexture::CopyTexSubImage(unsigned target,
                                     const gfx::Point& offset,
                                     const gfx::Rect& rect) {
-  if (target != GL_TEXTURE_2D)
-    return false;
-
-  if (!owner_stub_ || !surface_texture_.get())
-    return true;
-
-  if (!offset.IsOrigin()) {
-    LOG(ERROR) << "Non-origin offset is not supported";
-    return false;
-  }
-
-  if (rect != gfx::Rect(size_)) {
-    LOG(ERROR) << "Sub-rectangle is not supported";
-    return false;
-  }
-
-  GLint target_texture = 0;
-  glGetIntegerv(GL_TEXTURE_BINDING_2D, &target_texture);
-  DCHECK(target_texture);
-
-  UpdateTexImage();
-
-  if (!framebuffer_) {
-    glGenFramebuffersEXT(1, &framebuffer_);
-
-    // This vertex shader introduces a y flip before applying the stream
-    // texture matrix.  This is required because the stream texture matrix
-    // Android provides is intended to  be used in a y-up coordinate system,
-    // whereas Chromium expects y-down.
-
-    // clang-format off
-    const char kVertexShader[] = STRINGIZE(
-      attribute vec2 a_position;
-      varying vec2 v_texCoord;
-      uniform mat4 u_xform;
-      void main() {
-        gl_Position = vec4(a_position.x, a_position.y, 0.0, 1.0);
-        vec2 uv_untransformed = a_position * vec2(0.5, -0.5) + vec2(0.5, 0.5);
-        v_texCoord = (u_xform * vec4(uv_untransformed, 0.0, 1.0)).xy;
-      }
-    );
-    const char kFragmentShader[] =
-      "#extension GL_OES_EGL_image_external : require\n" STRINGIZE(
-      precision mediump float;
-      uniform samplerExternalOES a_texture;
-      varying vec2 v_texCoord;
-      void main() {
-        gl_FragColor = texture2D(a_texture, v_texCoord);
-      }
-    );
-    // clang-format on
-
-    vertex_buffer_ = gfx::GLHelper::SetupQuadVertexBuffer();
-    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_);
-    int sampler_location = glGetUniformLocation(program_, "a_texture");
-    DCHECK_NE(-1, sampler_location);
-    glUniform1i(sampler_location, 0);
-    u_xform_location_ = glGetUniformLocation(program_, "u_xform");
-    DCHECK_NE(-1, u_xform_location_);
-  }
-
-  gfx::ScopedActiveTexture active_texture(GL_TEXTURE0);
-  // UpdateTexImage() call below will bind the surface texture to
-  // TEXTURE_EXTERNAL_OES. This scoped texture binder will restore the current
-  // binding before this function returns.
-  gfx::ScopedTextureBinder texture_binder(GL_TEXTURE_EXTERNAL_OES, texture_id_);
-
-  {
-    gfx::ScopedFrameBufferBinder framebuffer_binder(framebuffer_);
-    gfx::ScopedViewport viewport(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_);
-
-    glUniformMatrix4fv(u_xform_location_, 1, false, current_matrix_);
-    gfx::GLHelper::DrawQuad(vertex_buffer_);
-
-    // Detach the output texture from the fbo.
-    glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
-                              GL_TEXTURE_2D, 0, 0);
-  }
-  return true;
+  return false;
 }
 
 bool StreamTexture::ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                                          int z_order,
                                          gfx::OverlayTransform transform,
                                          const gfx::Rect& bounds_rect,
                                          const gfx::RectF& crop_rect) {
   NOTREACHED();
   return false;
 }
 
 void StreamTexture::OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                                  uint64_t process_tracing_id,
                                  const std::string& dump_name) {
   // TODO(ericrk): Add OnMemoryDump for GLImages. crbug.com/514914
 }
 
 }  // namespace content