Mostly seem to have fixed SDL_CalculateShapeTree. Mostly. There still seem to be some rendering artifacts, stepping effects, and such on Windows -- which indicates subtle logic errors in SDL_CalculateShapeTree(). Oh well, back into the salt mine.

/*
 *  jumphack.h
 *  SDLiPhoneOS
 *
 */

#ifndef _jumphack_h
#define _jumphack_h

#include "setjmp.h"

/* see SDL_uikitevents.m for more info */

extern jmp_buf *jump_env();

#endif