mask |= BUFFER_BIT_FRONT_RIGHT;
break;
case GL_BACK:
+ /* For GLES contexts with a single buffered configuration, we actually
+ * only have a front renderbuffer, so any clear calls to GL_BACK should
+ * affect that buffer. See draw_buffer_enum_to_bitmask for details.
+ */
+ if (_mesa_is_gles(ctx))
+ if (!ctx->DrawBuffer->Visual.doubleBufferMode)
+ if (att[BUFFER_FRONT_LEFT].Renderbuffer)
+ mask |= BUFFER_BIT_FRONT_LEFT;
if (att[BUFFER_BACK_LEFT].Renderbuffer)
mask |= BUFFER_BIT_BACK_LEFT;
if (att[BUFFER_BACK_RIGHT].Renderbuffer)