gpu, cmaa: reuse CopyTextureCHROMIUMResourceManager

gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc

Index: gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc b/gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc
index 6f411353803a30ed09f163944d7355ab204c54ae..4e53cc8d0c338aac0bce2e3d24d62d865ea47421 100644
--- a/gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc
+++ b/gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc
@@ -185,6 +185,8 @@ void ApplyFramebufferAttachmentCMAAINTELResourceManager::Initialize(
   process_and_apply_shader_result_rgba_texture_slot1_ = glGetUniformLocation(
       process_and_apply_shader_, "g_resultRGBATextureSlot1");
 
+  copy_to_framebuffer_shader_ = CreateProgram("", vert_str_, copy_frag_str_);
+
   initialized_ = true;
 }
 
@@ -194,6 +196,7 @@ void ApplyFramebufferAttachmentCMAAINTELResourceManager::Destroy() {
 
   ReleaseTextures();
 
+  glDeleteProgram(copy_to_framebuffer_shader_);
   glDeleteProgram(process_and_apply_shader_);
   glDeleteProgram(edges_combine_shader_);
   glDeleteProgram(edges1_shader_);
@@ -245,16 +248,11 @@ void ApplyFramebufferAttachmentCMAAINTELResourceManager::
       // CMAA Effect
       if (do_copy) {
         ApplyCMAAEffectTexture(source_texture, rgba8_texture_, do_copy);
+        CopyTexture(rgba8_texture_, source_texture);
       } else {
         ApplyCMAAEffectTexture(source_texture, source_texture, do_copy);
       }
 
-      // Copy rgba8_texture_ to source_texture
-      if (do_copy) {
-        // copy_framebuffer_ always binds rgba8_texture_
-        glBindFramebufferEXT(GL_FRAMEBUFFER, copy_framebuffer_);
-        CopyTexture(source_texture);
-      }
       decoder->RestoreTextureState(source_texture);
     }
   }
@@ -551,15 +549,42 @@ void ApplyFramebufferAttachmentCMAAINTELResourceManager::ReleaseTextures() {
 }
 
 void ApplyFramebufferAttachmentCMAAINTELResourceManager::CopyTexture(

[piman, 2016/10/28 21:51:12]

We already have a facility to copy a texture using a draw, in
CopyTextureCHROMIUMResourceManager - that is used for CopyTextureCHROMIUM

Could we use that instead, to avoid duplicating functionality? We can pass the
CopyTextureCHROMIUMResourceManager to the
ApplyFramebufferAttachmentCMAAINTELResourceManager so that it can call into it.

+    GLint source,
     GLint dest) {
-  glActiveTexture(GL_TEXTURE0);
-  glBindTexture(GL_TEXTURE_2D, dest);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+  // glDrawArrays is faster than glCopyTexSubImage2D on IA Mesa driver,
+  // although opposite in Android. Currently, only IA ChromeOS uses this code.
+  const bool draw = true;

[dshwang, 2016/10/28 18:13:24]

Mesa may will fix it or future Intel Chromebook may have different behavior.
So I remain dead code here. It makes us to test very quickly.

+  if (draw) {
+    glBindFramebufferEXT(GL_FRAMEBUFFER, copy_framebuffer_);
+    glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                              GL_TEXTURE_2D, dest, 0);
+    glViewport(0, 0, width_, height_);
 
-  glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, width_, height_);
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, source);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_STENCIL_TEST);
+    glDisable(GL_CULL_FACE);
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+    glDepthMask(GL_FALSE);
+    glDisable(GL_BLEND);
+    glUseProgram(copy_to_framebuffer_shader_);
+
+    glDrawArrays(GL_TRIANGLES, 0, 3);
+    glUseProgram(0);
+    glBindTexture(GL_TEXTURE_2D, 0);
+  } else {
+    // copy_framebuffer_ always binds rgba8_texture_
+    glBindFramebufferEXT(GL_FRAMEBUFFER, copy_framebuffer_);
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, dest);
+    glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, width_, height_);
+  }
 }
 
 GLuint ApplyFramebufferAttachmentCMAAINTELResourceManager::CreateProgram(
@@ -1861,6 +1886,19 @@ const char ApplyFramebufferAttachmentCMAAINTELResourceManager::cmaa_frag_s2_[] =
     \n#endif\n
     }
   );
+
+const char
+  ApplyFramebufferAttachmentCMAAINTELResourceManager::copy_frag_str_[] =
+    SHADER(
+      precision highp float;
+      layout(binding = 0) uniform highp sampler2D inTexture;
+      layout(location = 0) out vec4 outColor;
+      void main() {
+        ivec2 screenPosI = ivec2( gl_FragCoord.xy );
+        vec4 pixel = texelFetch(inTexture, screenPosI, 0);
+        outColor = pixel;
+      }
+    );
 /* clang-format on */
 
 }  // namespace gles2