Disallow drawing feedback loops.
BUG=421695
TEST=gpu_unittests, webgl_conformance_tests
[email protected]
Review URL: https://codereview.chromium.org/653203004
Cr-Commit-Position: refs/heads/master@{#300019}
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index f52c10e2..67b6efa2 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -1202,6 +1202,11 @@
// location is not -1.
bool CheckCurrentProgramForUniform(GLint location, const char* function_name);
+ // Checks if the current program samples a texture that is also the color
+ // image of the current bound framebuffer, i.e., the source and destination
+ // of the draw operation are the same.
+ bool CheckDrawingFeedbackLoops();
+
// Gets the type of a uniform for a location in the current program. Sets GL
// errors if the current program is not valid. Returns true if the current
// program is valid and the location exists. Adjusts count so it
@@ -5750,6 +5755,38 @@
return location != -1;
}
+bool GLES2DecoderImpl::CheckDrawingFeedbackLoops() {
+ Framebuffer* framebuffer = GetFramebufferInfoForTarget(GL_FRAMEBUFFER);
+ if (!framebuffer)
+ return false;
+ const Framebuffer::Attachment* attachment =
+ framebuffer->GetAttachment(GL_COLOR_ATTACHMENT0);
+ if (!attachment)
+ return false;
+
+ DCHECK(state_.current_program.get());
+ const Program::SamplerIndices& sampler_indices =
+ state_.current_program->sampler_indices();
+ for (size_t ii = 0; ii < sampler_indices.size(); ++ii) {
+ const Program::UniformInfo* uniform_info =
+ state_.current_program->GetUniformInfo(sampler_indices[ii]);
+ DCHECK(uniform_info);
+ if (uniform_info->type != GL_SAMPLER_2D)
+ continue;
+ for (size_t jj = 0; jj < uniform_info->texture_units.size(); ++jj) {
+ GLuint texture_unit_index = uniform_info->texture_units[jj];
+ if (texture_unit_index >= state_.texture_units.size())
+ continue;
+ TextureUnit& texture_unit = state_.texture_units[texture_unit_index];
+ TextureRef* texture_ref =
+ texture_unit.GetInfoForSamplerType(GL_SAMPLER_2D).get();
+ if (attachment->IsTexture(texture_ref))
+ return true;
+ }
+ }
+ return false;
+}
+
bool GLES2DecoderImpl::PrepForSetUniformByLocation(
GLint fake_location,
const char* function_name,
@@ -6246,6 +6283,13 @@
return false;
}
+ if (CheckDrawingFeedbackLoops()) {
+ LOCAL_SET_GL_ERROR(
+ GL_INVALID_OPERATION, function_name,
+ "Source and destination textures of the draw are the same.");
+ return false;
+ }
+
return state_.vertex_attrib_manager
->ValidateBindings(function_name,
this,
