// ============================================================================
void SetDrawtoField(int);
+void BackToFront(void);
int el2img_mm(int);
int el_act2img_mm(int, int);
void CheckSingleStepMode_MM(boolean, boolean);
+void ShowEnvelope(int);
int getGraphicAnimationFrame(int, int);
int getGraphicAnimationFrameXY(int, int, int);