+/**
+ * Create a renderbuffer which will be set up by the driver to wrap the
+ * texture image slice.
+ *
+ * By using a gl_renderbuffer (like user-allocated renderbuffers), drivers get
+ * to share most of their framebuffer rendering code between winsys,
+ * renderbuffer, and texture attachments.
+ *
+ * The allocated renderbuffer uses a non-zero Name so that drivers can check
+ * it for determining vertical orientation, but we use ~0 to make it fairly
+ * unambiguous with actual user (non-texture) renderbuffers.
+ */
+void
+_mesa_update_texture_renderbuffer(struct gl_context *ctx,
+ struct gl_framebuffer *fb,
+ struct gl_renderbuffer_attachment *att)
+{
+ struct gl_texture_image *texImage;
+ struct gl_renderbuffer *rb;
+
+ texImage = _mesa_get_attachment_teximage(att);
+ if (!texImage)
+ return;
+
+ rb = att->Renderbuffer;
+ if (!rb) {
+ rb = ctx->Driver.NewRenderbuffer(ctx, ~0);
+ if (!rb) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glFramebufferTexture()");
+ return;
+ }
+ _mesa_reference_renderbuffer(&att->Renderbuffer, rb);
+
+ /* This can't get called on a texture renderbuffer, so set it to NULL
+ * for clarity compared to user renderbuffers.
+ */
+ rb->AllocStorage = NULL;
+ }
+
+ ctx->Driver.RenderTexture(ctx, fb, att);
+}