gpu: Use a rectangle to keep track of the cleared area of each texture level.

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index c4918f32ba591c0e554c8896f9ca96a9ddb3ab71..a8b3b7032046a1f64fe8f52afde48882bc9189e5 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -1270,12 +1270,12 @@ class GLES2DecoderImpl : public GLES2Decoder,
   bool ClearLevel(Texture* texture,
                   unsigned target,
                   int level,
-                  unsigned internal_format,
                   unsigned format,
                   unsigned type,
+                  int xoffset,
+                  int yoffset,
                   int width,
-                  int height,
-                  bool is_texture_immutable) override;
+                  int height) override;
 
   // Restore all GL state that affects clearing.
   void RestoreClearState();
@@ -3550,7 +3550,7 @@ bool GLES2DecoderImpl::CheckFramebufferValid(
 
   // Are all the attachments cleared?
   if (renderbuffer_manager()->HaveUnclearedRenderbuffers() ||
-      texture_manager()->HaveUnclearedMips()) {
+      texture_manager()->HaveUnsafeTextures()) {
     if (!framebuffer->IsCleared()) {
       // Can we clear them?
       if (framebuffer->GetStatus(texture_manager(), target) !=
@@ -3685,17 +3685,12 @@ void GLES2DecoderImpl::UpdateParentTextureInfo() {
   GLenum target = offscreen_saved_color_texture_info_->texture()->target();
   glBindTexture(target, offscreen_saved_color_texture_info_->service_id());
   texture_manager()->SetLevelInfo(
-      offscreen_saved_color_texture_info_.get(),
-      GL_TEXTURE_2D,
+      offscreen_saved_color_texture_info_.get(), GL_TEXTURE_2D,
       0,  // level
-      GL_RGBA,
-      offscreen_size_.width(),
-      offscreen_size_.height(),
+      GL_RGBA, offscreen_size_.width(), offscreen_size_.height(),
       1,  // depth
       0,  // border
-      GL_RGBA,
-      GL_UNSIGNED_BYTE,
-      true);
+      GL_RGBA, GL_UNSIGNED_BYTE, gfx::Rect(offscreen_size_));
   texture_manager()->SetParameteri(
       "UpdateParentTextureInfo",
       GetErrorState(),
@@ -8864,19 +8859,18 @@ void GLES2DecoderImpl::DoBufferSubData(
       &state_, target, offset, size, data);
 }
 
-bool GLES2DecoderImpl::ClearLevel(
-    Texture* texture,
-    unsigned target,
-    int level,
-    unsigned internal_format,
-    unsigned format,
-    unsigned type,
-    int width,
-    int height,
-    bool is_texture_immutable) {
+bool GLES2DecoderImpl::ClearLevel(Texture* texture,
+                                  unsigned target,
+                                  int level,
+                                  unsigned format,
+                                  unsigned type,
+                                  int xoffset,
+                                  int yoffset,
+                                  int width,
+                                  int height) {
   uint32 channels = GLES2Util::GetChannelsForFormat(format);
   if (feature_info_->feature_flags().angle_depth_texture &&
-      (channels & GLES2Util::kDepth) != 0) {
+      (channels & GLES2Util::kDepth) != 0 && xoffset == 0 && yoffset == 0) {
     // It's a depth format and ANGLE doesn't allow texImage2D or texSubImage2D
     // on depth formats.
     GLuint fb = 0;
@@ -8949,17 +8943,11 @@ bool GLES2DecoderImpl::ClearLevel(
   memset(zero.get(), 0, size);
   glBindTexture(texture->target(), texture->service_id());
 
-  bool has_images = texture->HasImages();
   GLint y = 0;
   while (y < height) {
     GLint h = y + tile_height > height ? height - y : tile_height;
-    if (is_texture_immutable || h != height || has_images) {
-      glTexSubImage2D(target, level, 0, y, width, h, format, type, zero.get());
-    } else {
-      glTexImage2D(
-          target, level, internal_format, width, h, 0, format, type,
-          zero.get());
-    }
+    glTexSubImage2D(target, level, xoffset, yoffset + y, width, h, format, type,
+                    zero.get());
     y += tile_height;
   }
   TextureRef* bound_texture =
@@ -9320,9 +9308,9 @@ error::Error GLES2DecoderImpl::DoCompressedTexImage2D(
       target, level, internal_format, width, height, border, image_size, data);
   GLenum error = LOCAL_PEEK_GL_ERROR("glCompressedTexImage2D");
   if (error == GL_NO_ERROR) {
-    texture_manager()->SetLevelInfo(
-        texture_ref, target, level, internal_format,
-        width, height, 1, border, 0, 0, true);
+    texture_manager()->SetLevelInfo(texture_ref, target, level, internal_format,
+                                    width, height, 1, border, 0, 0,
+                                    gfx::Rect(width, height));
   }
 
   // This may be a slow command.  Exit command processing to allow for
@@ -9507,9 +9495,9 @@ error::Error GLES2DecoderImpl::DoCompressedTexImage3D(
                          border, image_size, data);
   GLenum error = LOCAL_PEEK_GL_ERROR("glCompressedTexImage3D");
   if (error == GL_NO_ERROR) {
-    texture_manager()->SetLevelInfo(
-        texture_ref, target, level, internal_format,
-        width, height, depth, border, 0, 0, true);
+    texture_manager()->SetLevelInfo(texture_ref, target, level, internal_format,
+                                    width, height, depth, border, 0, 0,
+                                    gfx::Rect(width, height));
   }
 
   // This may be a slow command.  Exit command processing to allow for
@@ -9963,8 +9951,8 @@ void GLES2DecoderImpl::DoCopyTexImage2D(
       copyWidth != width ||
       copyHeight != height) {
     // some part was clipped so clear the texture.
-    if (!ClearLevel(texture, target, level, internal_format, internal_format,
-                    GL_UNSIGNED_BYTE, width, height, texture->IsImmutable())) {
+    if (!ClearLevel(texture, target, level, internal_format, GL_UNSIGNED_BYTE,
+                    0, 0, width, height)) {
       LOCAL_SET_GL_ERROR(
           GL_OUT_OF_MEMORY, "glCopyTexImage2D", "dimensions too big");
       return;
@@ -9986,9 +9974,9 @@ void GLES2DecoderImpl::DoCopyTexImage2D(
   }
   GLenum error = LOCAL_PEEK_GL_ERROR("glCopyTexImage2D");
   if (error == GL_NO_ERROR) {
-    texture_manager()->SetLevelInfo(
-        texture_ref, target, level, internal_format, width, height, 1,
-        border, internal_format, GL_UNSIGNED_BYTE, true);
+    texture_manager()->SetLevelInfo(texture_ref, target, level, internal_format,
+                                    width, height, 1, border, internal_format,
+                                    GL_UNSIGNED_BYTE, gfx::Rect(width, height));
   }
 
   // This may be a slow command.  Exit command processing to allow for
@@ -10076,6 +10064,8 @@ void GLES2DecoderImpl::DoCopyTexSubImage2D(
 
   if (xoffset != 0 || yoffset != 0 || width != size.width() ||
       height != size.height()) {
+    // TODO(reveman): Use SetLevelClearedRect when possible instead of clearing
+    // the texture prematurely.
     if (!texture_manager()->ClearTextureLevel(this, texture_ref, target,
                                               level)) {
       LOCAL_SET_GL_ERROR(GL_OUT_OF_MEMORY, "glCopyTexSubImage2D",
@@ -10225,6 +10215,8 @@ error::Error GLES2DecoderImpl::DoTexSubImage2D(
   DCHECK(ok);
   if (xoffset != 0 || yoffset != 0 ||
       width != tex_width || height != tex_height) {
+    // TODO(reveman): Use SetLevelClearedRect when possible instead of clearing
+    // the texture prematurely.
     if (!texture_manager()->ClearTextureLevel(this, texture_ref,
                                               target, level)) {
       LOCAL_SET_GL_ERROR(
@@ -11741,8 +11733,8 @@ void GLES2DecoderImpl::DoTexImageIOSurface2DCHROMIUM(
   }
 
   texture_manager()->SetLevelInfo(
-      texture_ref, target, 0, GL_RGBA, width, height, 1, 0,
-      GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, true);
+      texture_ref, target, 0, GL_RGBA, width, height, 1, 0, GL_BGRA,
+      GL_UNSIGNED_INT_8_8_8_8_REV, gfx::Rect(width, height));
 
 #else
   LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION,
@@ -11965,7 +11957,8 @@ void GLES2DecoderImpl::DoCopyTextureCHROMIUM(GLenum target,
 
     texture_manager()->SetLevelInfo(
         dest_texture_ref, GL_TEXTURE_2D, 0, internal_format, source_width,
-        source_height, 1, 0, internal_format, dest_type, true);
+        source_height, 1, 0, internal_format, dest_type,
+        gfx::Rect(source_width, source_height));
   } else {
     texture_manager()->SetLevelCleared(dest_texture_ref, GL_TEXTURE_2D, 0,
                                        true);
@@ -12111,11 +12104,22 @@ void GLES2DecoderImpl::DoCopySubTextureCHROMIUM(GLenum target,
   DCHECK(ok);
   if (xoffset != 0 || yoffset != 0 || width != dest_width ||
       height != dest_height) {
-    if (!texture_manager()->ClearTextureLevel(this, dest_texture_ref, target,
-                                              0)) {
-      LOCAL_SET_GL_ERROR(GL_OUT_OF_MEMORY, "glCopySubTextureCHROMIUM",
-                         "destination texture dimensions too big");
-      return;
+    gfx::Rect cleared_rect(xoffset, yoffset, width, height);
+    gfx::Rect level_cleared_rect = dest_texture->GetLevelClearedRect(target, 0);
+    // Try to grow cleared rectangle.
+    if (level_cleared_rect.IsEmpty() ||
+        level_cleared_rect.SharesEdgeWith(cleared_rect)) {
+      cleared_rect.Union(level_cleared_rect);
+      texture_manager()->SetLevelClearedRect(dest_texture_ref, target, 0,
+                                             cleared_rect);
+    } else {
+      // Otherwise clear part of texture level that is not already cleared.
+      if (!texture_manager()->ClearTextureLevel(this, dest_texture_ref, target,
+                                                0)) {
+        LOCAL_SET_GL_ERROR(GL_OUT_OF_MEMORY, "glCopySubTextureCHROMIUM",
+                           "destination texture dimensions too big");
+        return;
+      }
     }
   } else {
     texture_manager()->SetLevelCleared(dest_texture_ref, GL_TEXTURE_2D, 0,
@@ -12261,9 +12265,9 @@ void GLES2DecoderImpl::DoTexStorage2DEXT(
     GLsizei level_width = width;
     GLsizei level_height = height;
     for (int ii = 0; ii < levels; ++ii) {
-      texture_manager()->SetLevelInfo(
-          texture_ref, target, ii, format,
-          level_width, level_height, 1, 0, format, type, false);
+      texture_manager()->SetLevelInfo(texture_ref, target, ii, format,
+                                      level_width, level_height, 1, 0, format,
+                                      type, gfx::Rect());
       level_width = std::max(1, level_width >> 1);
       level_height = std::max(1, level_height >> 1);
     }
@@ -12613,9 +12617,9 @@ void GLES2DecoderImpl::DoBindTexImage2DCHROMIUM(
 
   gfx::Size size = gl_image->GetSize();
   texture_manager()->SetLevelInfo(
-      texture_ref, target, 0, gl_image->GetInternalFormat(),
-      size.width(), size.height(), 1, 0,
-      gl_image->GetInternalFormat(), GL_UNSIGNED_BYTE, true);
+      texture_ref, target, 0, gl_image->GetInternalFormat(), size.width(),
+      size.height(), 1, 0, gl_image->GetInternalFormat(), GL_UNSIGNED_BYTE,
+      gfx::Rect(size));
   texture_manager()->SetLevelImage(texture_ref, target, 0, gl_image);
 }
 
@@ -12654,7 +12658,7 @@ void GLES2DecoderImpl::DoReleaseTexImage2DCHROMIUM(
 
   texture_manager()->SetLevelInfo(
       texture_ref, target, 0, gl_image->GetInternalFormat(), 0, 0, 1, 0,
-      gl_image->GetInternalFormat(), GL_UNSIGNED_BYTE, false);
+      gl_image->GetInternalFormat(), GL_UNSIGNED_BYTE, gfx::Rect());
 }
 
 error::Error GLES2DecoderImpl::HandleTraceBeginCHROMIUM(