Handle compressed textures allocated via TexStorage2D.

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 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 "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 1242 matching lines @@
                   unsigned target,
                   int level,
                   unsigned format,
                   unsigned type,
                   int xoffset,
                   int yoffset,
                   int width,
                   int height) override;
 
   // overridden from GLES2Decoder
+  bool ClearCompressedTextureLevel(Texture* texture,
+                                   unsigned target,
+                                   int level,
+                                   unsigned format,
+                                   int width,
+                                   int height) override;
+
+  // overridden from GLES2Decoder
   bool ClearLevel3D(Texture* texture,
                     unsigned target,
                     int level,
                     unsigned format,
                     unsigned type,
                     int width,
                     int height,
                     int depth) override;
 
   // Restore all GL state that affects clearing.
@@ skipping 9136 matching lines @@
                     zero.get());
     y += tile_height;
   }
   TextureRef* bound_texture =
       texture_manager()->GetTextureInfoForTarget(&state_, texture->target());
   glBindTexture(texture->target(),
                 bound_texture ? bound_texture->service_id() : 0);
   return true;
 }
 
+bool GLES2DecoderImpl::ClearCompressedTextureLevel(Texture* texture,
+                                                   unsigned target,
+                                                   int level,
+                                                   unsigned format,
+                                                   int width,
+                                                   int height) {
+  DCHECK(target != GL_TEXTURE_3D && target != GL_TEXTURE_2D_ARRAY);
+  // This code path can only be called if the texture was originally
+  // allocated via TexStorage2D.

[Zhenyao Mo, 2016/04/28 17:57:13]

nit: can you also add a comment here that although we do expose TexStorage2D
internally for ES2, but compressed formats are not part of it?

[Ken Russell (switch to Gerrit), 2016/04/29 13:10:06]

Done.

+  DCHECK(feature_info_->IsES3Enabled());
+
+  GLsizei bytes_required = 0;
+  if (!GetCompressedTexSizeInBytes(
+          "ClearCompressedTextureLevel", width, height, 1, format,
+          &bytes_required)) {
+    return false;
+  }
+
+  TRACE_EVENT1("gpu", "GLES2DecoderImpl::ClearCompressedTextureLevel",
+               "bytes_required", bytes_required);
+
+  std::unique_ptr<char[]> zero(new char[bytes_required]);
+  memset(zero.get(), 0, bytes_required);
+  glBindTexture(texture->target(), texture->service_id());

[Zhenyao Mo, 2016/04/28 17:57:13]

You also need to unbind the PIXEL_UNPACK_BUFFER if one is bound, and recover the
binding in the end of this function.

[Ken Russell (switch to Gerrit), 2016/04/29 13:10:06]

Thanks for pointing that out. Done.

+  glCompressedTexSubImage2D(
+      target, level, 0, 0, width, height, format, bytes_required, zero.get());
+  TextureRef* bound_texture =
+      texture_manager()->GetTextureInfoForTarget(&state_, texture->target());
+  glBindTexture(texture->target(),
+                bound_texture ? bound_texture->service_id() : 0);
+  return true;
+}
+
 bool GLES2DecoderImpl::ClearLevel3D(Texture* texture,
                                     unsigned target,
                                     int level,
                                     unsigned format,
                                     unsigned type,
                                     int width,
                                     int height,
                                     int depth) {
   DCHECK(target == GL_TEXTURE_3D || target == GL_TEXTURE_2D_ARRAY);
   DCHECK(feature_info_->IsES3Enabled());
@@ skipping 1196 matching lines @@
   }
 
   if (!ValidateCompressedTexFuncData("glCompressedTexSubImage2D",
                                      width, height, 1, format, image_size) ||
       !ValidateCompressedTexSubDimensions("glCompressedTexSubImage2D",
                                           target, level, xoffset, yoffset, 0,
                                           width, height, 1, format, texture)) {
     return;
   }
 
+  if (!texture->IsLevelCleared(target, level)) {
+    // This can only happen if the compressed texture was allocated
+    // using TexStorage2D.
+    DCHECK(texture->IsImmutable());
+    GLsizei level_width = 0, level_height = 0;
+    bool success = texture->GetLevelSize(
+        target, level, &level_width, &level_height, nullptr);
+    DCHECK(success);
+    // We can skip the clear if we're uploading the entire level.
+    if (xoffset == 0 && yoffset == 0 &&
+        width == level_width && height == level_height) {
+      texture_manager()->SetLevelCleared(texture_ref, target, level, true);
+    } else {
+      texture_manager()->ClearTextureLevel(this, texture_ref, target, level);
+    }
+    DCHECK(texture->IsLevelCleared(target, level));
+  }
 
-  // Note: There is no need to deal with texture cleared tracking here
-  // because the validation above means you can only get here if the level
-  // is already a matching compressed format and in that case
-  // CompressedTexImage2D already cleared the texture.
   glCompressedTexSubImage2D(
       target, level, xoffset, yoffset, width, height, format, image_size, data);
 
   // This may be a slow command.  Exit command processing to allow for
   // context preemption and GPU watchdog checks.
   ExitCommandProcessingEarly();
 }
 
 static void Clip(
     GLint start, GLint range, GLint sourceRange,
@@ skipping 2674 matching lines @@
   }
   if (levels <= 0) {
     LOCAL_SET_GL_ERROR(GL_INVALID_VALUE, function_name, "levels <= 0");
     return;
   }
   if (!validators_->texture_internal_format_storage.IsValid(internal_format)) {
     LOCAL_SET_GL_ERROR_INVALID_ENUM(
         function_name, internal_format, "internal_format");
     return;
   }
-  bool is_compressed_format;
-  switch (internal_format) {
-    case GL_COMPRESSED_R11_EAC:
-    case GL_COMPRESSED_SIGNED_R11_EAC:
-    case GL_COMPRESSED_RG11_EAC:
-    case GL_COMPRESSED_SIGNED_RG11_EAC:
-    case GL_COMPRESSED_RGB8_ETC2:
-    case GL_COMPRESSED_SRGB8_ETC2:
-    case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2:
-    case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2:
-    case GL_COMPRESSED_RGBA8_ETC2_EAC:
-    case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC:
-      is_compressed_format = true;
-      if (target == GL_TEXTURE_3D) {
-        LOCAL_SET_GL_ERROR(
-            GL_INVALID_OPERATION, function_name, "target invalid for format");
-        return;
-      }
-      break;
-    default:
-      is_compressed_format = false;
-      break;
+  bool is_compressed_format = GLES2Util::IsCompressedTextureFormat(
+      internal_format);
+  if (is_compressed_format && target == GL_TEXTURE_3D) {
+    LOCAL_SET_GL_ERROR(
+        GL_INVALID_OPERATION, function_name, "target invalid for format");
+    return;
   }
+
   if (!texture_manager()->ValidForTarget(target, 0, width, height, depth) ||
       TextureManager::ComputeMipMapCount(
           target, width, height, depth) < levels) {
     LOCAL_SET_GL_ERROR(
         GL_INVALID_VALUE, function_name, "dimensions out of range");
     return;
   }
   TextureRef* texture_ref = texture_manager()->GetTextureInfoForTarget(
       &state_, target);
   if (!texture_ref) {
@@ skipping 2012 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu