fixes

software/demo/apipe.c

@@ -143,11 +143,13 @@ static void pfv_callback(struct pfpu_td *td)
 {
 	struct rpipe_frame *rpipe_frame;
 	int brightness256, brightness64, frame_mod;
+	float decay;
 
 	rpipe_frame = (struct rpipe_frame *)td->user;
 
-	brightness256 = 256.0*eval_read_pfv(eval, pfv_decay) + 0.5;
-	brightness64 = brightness256 >> 2;
+	decay = eval_read_pfv(eval, pfv_decay);
+	brightness256 = 255.0*decay+3.5;
+	brightness64 = (brightness256 >> 2)-1;
 	brightness256 &= 3;
 	frame_mod = rpipe_frame->framenr & 3;
 	if((brightness256 == 1) && (frame_mod == 0))
@@ -156,6 +158,7 @@ static void pfv_callback(struct pfpu_td *td)
 		brightness64++;
 	if((brightness256 == 3) && (frame_mod != 3))
 		brightness64++;
+	if(brightness64 < 0) brightness64 = 0;
 	if(brightness64 > 63) brightness64 = 63;
 	rpipe_frame->brightness = brightness64;
 

software/demo/eval.c

@@ -275,6 +275,8 @@ static int generate_perframe(struct eval_state *sc, struct preset *ast)
 	scheduler_dont_touch(&scheduler, compiler.terminals);
 	scheduler_schedule(&scheduler, compiler.prog, compiler.prog_length);
 	/* patch the program to make a dummy DMA at the end (otherwise PFPU never finishes) */
+	scheduler.last_exit++;
+	if(scheduler.last_exit == PFPU_PROGSIZE) return 0;
 	scheduler.prog[scheduler.last_exit].i.opcode = PFPU_OPCODE_VECTOUT;
 
 	#ifdef EVAL_DEBUG

software/demo/rpipe.c

@@ -191,6 +191,10 @@ static void rpipe_draw_motion_vectors()
 	int nx, ny;
 	int l;
 
+	if(bh_frame->mv_a == 0.0) return;
+	if(bh_frame->mv_x == 0.0) return;
+	if(bh_frame->mv_y == 0.0) return;
+
 	l = bh_frame->mv_l;
 	if(l > 10) l = 10;
 

software/demo/wave.c

@@ -33,6 +33,8 @@ void wave_draw(unsigned short *framebuffer, unsigned int hres, unsigned int vres
 	float wave_o;
 	int i;
 
+	if(nvertices == 0) return;
+
 	line_init_context(&ctx, framebuffer, hres, vres);
 
 	//TODO: implement modulate_opacity_by_volume