During virtual context switches only restore texture units that have changed from the previous cont…

gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
index 910cb0104b214ec80de4dd7872f5a70f1904a145..f39b52bfbcd96aa62167ac1e631426694c263bd5 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
@@ -14,6 +14,7 @@
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_mock.h"
 #include "gpu/command_buffer/service/cmd_buffer_engine.h"
 #include "gpu/command_buffer/service/context_group.h"
+#include "gpu/command_buffer/service/context_state.h"
 #include "gpu/command_buffer/service/gl_surface_mock.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
@@ -8820,6 +8821,99 @@ TEST_F(GLES2DecoderTest, DiscardFramebufferEXTUnsupported) {
   EXPECT_EQ(GL_INVALID_OPERATION, GetGLError());
 }
 
+TEST_F(GLES2DecoderManualInitTest, RestoreState) {
+  InitDecoder(
+      "",      // extensions
+      false,   // has alpha
+      false,   // has depth
+      false,   // has stencil
+      false,   // request alpha
+      false,   // request depth
+      false,   // request stencil
+      false);  // bind generates resource
+  SetupTexture();
+
+  InSequence sequence;
+  // Expect to restore texture bindings for unit GL_TEXTURE0.
+  EXPECT_CALL(*gl_, ActiveTexture(GL_TEXTURE0))
+      .Times(1)
+      .RetiresOnSaturation();
+  EXPECT_CALL(*gl_, BindTexture(GL_TEXTURE_2D, kServiceTextureId))
+      .Times(1)
+      .RetiresOnSaturation();
+  EXPECT_CALL(*gl_, BindTexture(GL_TEXTURE_CUBE_MAP,
+                                TestHelper::kServiceDefaultTextureCubemapId))
+      .Times(1)
+      .RetiresOnSaturation();
+
+  // Expect to restore texture bindings for remaining units.
+  for (unsigned i = 0; i < group().max_texture_units() - 1; ++i) {
+    EXPECT_CALL(*gl_, ActiveTexture(GL_TEXTURE1 + i))
+        .Times(1)
+        .RetiresOnSaturation();
+    EXPECT_CALL(*gl_, BindTexture(GL_TEXTURE_2D,
+                                  TestHelper::kServiceDefaultTexture2dId))
+        .Times(1)
+        .RetiresOnSaturation();
+    EXPECT_CALL(*gl_, BindTexture(GL_TEXTURE_CUBE_MAP,
+                                  TestHelper::kServiceDefaultTextureCubemapId))
+        .Times(1)
+        .RetiresOnSaturation();
+  }
+
+  // Expect to restore the active texture unit to GL_TEXTURE0.
+  EXPECT_CALL(*gl_, ActiveTexture(GL_TEXTURE0))
+      .Times(1)
+      .RetiresOnSaturation();
+
+  GetDecoder()->RestoreAllTextureUnitBindings(NULL);
+}
+
+TEST_F(GLES2DecoderManualInitTest, RestoreStateWithPreviousState) {

[Ken Russell (switch to Gerrit), 2014/01/08 02:56:28]

Could you please add a couple more tests?

 - Having a non-default texture bound to another texture unit than GL_TEXTURE0
 - Switching between two ContextStates, one with a non-default texture bound to
GL_TEXTURE0's GL_TEXTURE2D binding point, the other with one bound to
GL_TEXTURE1, and verify the right thing happens when switching from one to the
other and back

+  InitDecoder(
+      "",      // extensions
+      false,   // has alpha
+      false,   // has depth
+      false,   // has stencil
+      false,   // request alpha
+      false,   // request depth
+      false,   // request stencil
+      false);  // bind generates resource
+  SetupTexture();
+
+  // Construct a previous ContextState  with all texture bindings
+  // set to default textures.
+  ContextState prev_state(NULL, NULL);
+  prev_state.texture_units.resize(group().max_texture_units());
+  for (uint32 tt = 0; tt < prev_state.texture_units.size(); ++tt) {
+    TextureRef* ref_cube_map =
+        group().texture_manager()->GetDefaultTextureInfo(GL_TEXTURE_CUBE_MAP);
+    prev_state.texture_units[tt].bound_texture_cube_map = ref_cube_map;
+    TextureRef* ref_2d =
+        group().texture_manager()->GetDefaultTextureInfo(GL_TEXTURE_2D);
+    prev_state.texture_units[tt].bound_texture_2d = ref_2d;
+  }
+  prev_state.active_texture_unit = 0;
+
+  InSequence sequence;
+  // Expect to restore only GL_TEXTURE_2D binding for GL_TEXTURE0 unit,
+  // since the rest of the bindings haven't changed between the current
+  // state and the |prev_state|.
+  EXPECT_CALL(*gl_, ActiveTexture(GL_TEXTURE0))
+      .Times(1)
+      .RetiresOnSaturation();
+  EXPECT_CALL(*gl_, BindTexture(GL_TEXTURE_2D, kServiceTextureId))
+      .Times(1)
+      .RetiresOnSaturation();
+
+  // Expect to restore active texture unit to GL_TEXTURE0.
+  EXPECT_CALL(*gl_, ActiveTexture(GL_TEXTURE0))
+      .Times(1)
+      .RetiresOnSaturation();
+
+  GetDecoder()->RestoreAllTextureUnitBindings(&prev_state);
+}
+
 // TODO(gman): Complete this test.
 // TEST_F(GLES2DecoderTest, CompressedTexImage2DGLError) {
 // }