Add extra state reset for draw buffers indexed state.

Some drivers have bugs with GL_EXT_draw_buffers_indexed state. Common functions,
e.g. glBlendFunc(), fail to reset indexed state. These extra function calls make
sure that state gets reset to initial values.

Change-Id: I06b709ef81efb0ecfdbe1f88ac94dca49f39d7dc

diff --git a/framework/opengl/gluStateReset.cpp b/framework/opengl/gluStateReset.cpp
index ac2962b..3902bd0 100644 (file)
--- a/framework/opengl/gluStateReset.cpp
+++ b/framework/opengl/gluStateReset.cpp
@@ -306,6 +306,26 @@ void resetStateES (const RenderContext& renderCtx)
                GLU_EXPECT_NO_ERROR(gl.getError(), "Texture state reset failed");
        }
 
+       // Resetting state using non-indexed variants should be enough, but some
+       // implementations have bugs so we need to make sure indexed state gets
+       // set back to initial values.
+       if (ctxInfo->isExtensionSupported("GL_EXT_draw_buffers_indexed"))
+       {
+               int numDrawBuffers = 0;
+
+               gl.getIntegerv(GL_MAX_DRAW_BUFFERS, &numDrawBuffers);
+
+               for (int drawBufferNdx = 0; drawBufferNdx < numDrawBuffers; drawBufferNdx++)
+               {
+                       gl.disablei                     (GL_BLEND, drawBufferNdx);
+                       gl.blendFunci           (drawBufferNdx, GL_ONE, GL_ZERO);
+                       gl.blendEquationi       (drawBufferNdx, GL_FUNC_ADD);
+                       gl.colorMaski           (drawBufferNdx, GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+               }
+
+               GLU_EXPECT_NO_ERROR(gl.getError(), "Failed to reset indexed draw buffer state");
+       }
+
        // Pixel operations.
        {
                const tcu::RenderTarget& renderTarget = renderCtx.getRenderTarget();