intel / DRI2: When available, use DRI2GetBuffersWithFormat

This interface gives the driver two important features.  First, it can
allocate the (fake) front-buffer only when needed.  Second, it can
tell the buffer allocator the format of buffers being allocated.  This
enables support for back-buffer and depth-buffer with different bits
per pixel.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kristian Høgsberg <krh@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/intel/intel_buffers.c b/src/mesa/drivers/dri/intel/intel_buffers.c
index 90964df355..ecac5bf020 100644
--- a/src/mesa/drivers/dri/intel/intel_buffers.c
+++ b/src/mesa/drivers/dri/intel/intel_buffers.c
@@ -323,8 +323,18 @@ intelDrawBuffer(GLcontext * ctx, GLenum mode)
 {
    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
       struct intel_context *const intel = intel_context(ctx);
+      const GLboolean was_front_buffer_rendering =
+	intel->is_front_buffer_rendering;
 
       intel->is_front_buffer_rendering = (mode == GL_FRONT_LEFT);
+
+      /* If we weren't front-buffer rendering before but we are now, make sure
+       * that the front-buffer has actually been allocated.
+       */
+      if (!was_front_buffer_rendering && intel->is_front_buffer_rendering) {
+	 intel_update_renderbuffers(intel->driContext,
+				    intel->driContext->driDrawablePriv);
+      }
    }
 
    intel_draw_buffer(ctx, ctx->DrawBuffer);