--- uae/src/blitter.c	2018/04/24 17:05:48	1.1.1.11
+++ uae/src/blitter.c	2018/04/24 17:16:46	1.1.1.15
@@ -9,7 +9,6 @@
 #include "sysconfig.h"
 #include "sysdeps.h"
 
-#include "config.h"
 #include "options.h"
 #include "events.h"
 #include "uae.h"
@@ -37,6 +36,26 @@ uae_u32 blit_masktable[BLITTER_MAX_WORDS
 static uae_u16 blit_trashtable[BLITTER_MAX_WORDS];
 enum blitter_states bltstate;
 
+static uae_u8 blit_cycle_diagram_start[][10] =
+{
+    { 0, 1, 0 },		/* 0 */
+    { 0, 2, 4,0 },		/* 1 */
+    { 0, 2, 3,0 },		/* 2 */
+    { 2, 3, 3,0, 0,3,4 },	/* 3 */
+    { 0, 3, 2,0,0 },		/* 4 */
+    { 2, 3, 2,0, 0,2,4 },	/* 5 */
+    { 0, 3, 2,3,0 },		/* 6 */
+    { 3, 4, 2,3,0, 0,2,3,4 },	/* 7 */
+    { 0, 2, 1,0 },		/* 8 */
+    { 2, 2, 1,0, 1,4 },		/* 9 */
+    { 0, 2, 1,3 },		/* A */
+    { 3, 3, 1,3,0, 1,3,4 },	/* B */
+    { 2, 3, 1,2, 0,1,2 },	/* C */
+    { 3, 3, 1,2,0, 1,2,4 },	/* D */
+    { 0, 3, 1,2,3 },		/* E */
+    { 4, 4, 1,2,3,0, 1,2,3,4 }	/* F */
+};
+
 void build_blitfilltable(void)
 {
     unsigned int d, fillmask;
@@ -307,10 +326,13 @@ STATIC_INLINE void blitter_line_incy(voi
 
 static void blitter_line(void)
 {
-    uae_u16 blitahold = blinea >> blinea_shift, blitbhold = blineb & 1 ? 0xFFFF : 0, blitchold = blt_info.bltcdat;
+    uae_u16 blitahold = blinea >> blinea_shift;
+    uae_u16 blitbhold = blineb & 1 ? 0xFFFF : 0;
+    uae_u16 blitchold = blt_info.bltcdat;
     blt_info.bltddat = 0;
 
-    if (blitsing && blitonedot) blitahold = 0;
+    if (blitsing && blitonedot)
+	blitahold = 0;
     blitonedot = 1;
     blt_info.bltddat = blit_func(blitahold, blitbhold, blitchold, bltcon0 & 0xFF);
     if (!blitsign){
@@ -397,7 +419,7 @@ static void blit_init(void)
 	if (blitfill && !blitdesc) {
 	    static int warn = 1;
 	    if (warn)
-	        write_log ("warning: blitter fill without desc (further messages suppressed)\n");
+		write_log ("warning: blitter fill without desc (further messages suppressed)\n");
 	    warn = 0;
 	}
     }
@@ -413,9 +435,10 @@ static void actually_do_blit(void)
 	    blitter_nxline();
 	} while (bltstate != BLT_done);
     } else {
-	/*blitcount[bltcon0 & 0xff]++;  blitter debug */
-	if (blitdesc) blitter_dofast_desc();
-	else blitter_dofast();
+	if (blitdesc)
+	    blitter_dofast_desc();
+	else
+	    blitter_dofast();
     }
     blitter_done_notify ();
 }
@@ -435,20 +458,26 @@ void blitter_handler(void)
     unset_special (SPCFLAG_BLTNASTY);
 }
 
+static long int blit_cycles;
+static long blit_firstline_cycles;
+static long blit_first_cycle;
+static int blit_last_cycle;
+static uae_u8 *blit_diag;
+
 void do_blitter(void)
 {
-    long int blit_cycles;
-    if (!currprefs.immediate_blits) {
-
-	blit_cycles = 2;
+    int ch = (bltcon0 & 0x0f00) >> 8;
+    blit_diag = blit_cycle_diagram_start[ch];
 
+    blit_firstline_cycles = blit_first_cycle = get_cycles ();
+    blit_last_cycle = 0;
+    if (!currprefs.immediate_blits) {
 	if (!blitline) {
-	    if (bltcon0 & 0x400)
-		blit_cycles++;
-	    if ((bltcon0 & 0x300) == 0x300)
-		blit_cycles++;
+	    blit_cycles = blit_diag[1];
+	    blit_firstline_cycles += blit_cycles * blt_info.hblitsize * CYCLE_UNIT;
 	    blit_cycles *= blt_info.vblitsize * blt_info.hblitsize;
-	}
+	} else
+	     blit_cycles = 20; /* Desert Dream demo freezes if line draw is too fast */
     } else
 	blit_cycles = 1;
 
@@ -462,9 +491,10 @@ void do_blitter(void)
     unset_special (SPCFLAG_BLTNASTY);
     if (dmaen(DMA_BLITPRI))
 	set_special (SPCFLAG_BLTNASTY);
+
 }
 
-void maybe_blit (void)
+void maybe_blit (int modulo)
 {
     static int warned = 0;
     if (bltstate == BLT_done)
@@ -475,6 +505,34 @@ void maybe_blit (void)
 	write_log ("warning: Program does not wait for blitter\n");
     }
     if (!eventtab[ev_blitter].active)
-	printf("FOO!!?\n");
+	write_log ("FOO!!?\n");
+
+    if (modulo && get_cycles() < blit_firstline_cycles)
+	return;
     blitter_handler ();
 }
+
+int blitnasty (void)
+{
+    int cycles, ccnt;
+    if (!(regs.spcflags & SPCFLAG_BLTNASTY))
+	return 0;
+    if (bltstate == BLT_done)
+	return 0;
+    if (!dmaen(DMA_BLITTER))
+	return 0;
+    cycles = (get_cycles () - blit_first_cycle) / CYCLE_UNIT;
+    ccnt = 0;
+    while (blit_last_cycle < cycles) {
+	int c;
+	if (blit_last_cycle < blit_diag[0])
+	    c = blit_diag[blit_last_cycle + 2];
+	else
+	    c = blit_diag[((blit_last_cycle - blit_diag[0]) % blit_diag[1]) + 2 + blit_diag[0]];
+	blit_last_cycle ++;
+	if (!c)
+	    return 0;
+	ccnt++;
+    }
+    return ccnt;
+}