struct swrast_renderbuffer *xrb = swrast_renderbuffer(rb);
#define INIT_PIXEL_PTR(P, X, Y) \
GLushort *P = (GLushort *)row;
-#define INC_PIXEL_PTR(P) P += 2
+#define INC_PIXEL_PTR(P) P++
#define STORE_PIXEL(DST, X, Y, VALUE) \
STORE_PIXEL_R5G6B5(DST, X, Y, VALUE)
#define FETCH_PIXEL(DST, SRC) \