From 0c81be5e23f584bdf4e5a73d781494ef28c73781 Mon Sep 17 00:00:00 2001
From: Vince Weaver <vince@deater.net>
Date: Sat, 25 Nov 2023 00:16:15 -0500
Subject: [PATCH] gr-sim: dots: more work on dots nonsense

---
 utils/gr-sim/dots/Makefile       |  20 +-
 utils/gr-sim/dots/dots_dump.c    | 920 +++++++++++++++++++++++++++++++
 utils/gr-sim/dots/dots_minimal.c | 400 ++++++++++++++
 utils/gr-sim/dots/dots_play.c    |  64 +++
 4 files changed, 1402 insertions(+), 2 deletions(-)
 create mode 100644 utils/gr-sim/dots/dots_dump.c
 create mode 100644 utils/gr-sim/dots/dots_minimal.c
 create mode 100644 utils/gr-sim/dots/dots_play.c

diff --git a/utils/gr-sim/dots/Makefile b/utils/gr-sim/dots/Makefile
index ca91365f..069b3014 100644
--- a/utils/gr-sim/dots/Makefile
+++ b/utils/gr-sim/dots/Makefile
@@ -4,7 +4,23 @@ CFLAGS = -O2 -Wall -g
 SDL_LIBS= `sdl-config --libs`
 SDL_INCLUDE= `sdl-config --cflags`
 
-all:	dots
+all:	dots dots_dump dots_play
+
+###
+
+dots_play:	dots_play.o vga_emulator.o 8086_emulator.o ../gr-sim.a
+	$(CC) -o dots_play dots_play.o vga_emulator.o 8086_emulator.o ../gr-sim.a $(LFLAGS) $(SDL_LIBS)
+
+dots_play.o:	dots_play.c vga_emulator.h
+	$(CC) $(CFLAGS) $(SDL_INCLUDE) -c dots_play.c
+
+###
+
+dots_dump:	dots_dump.o vga_emulator.o 8086_emulator.o ../gr-sim.a
+	$(CC) -o dots_dump dots_dump.o vga_emulator.o 8086_emulator.o ../gr-sim.a $(LFLAGS) $(SDL_LIBS)
+
+dots_dump.o:	dots_dump.c vga_emulator.h
+	$(CC) $(CFLAGS) $(SDL_INCLUDE) -c dots_dump.c
 
 ###
 
@@ -27,4 +43,4 @@ vga_emulator.o:	vga_emulator.c vga_emulator.h
 ###
 
 clean:	
-	rm -f *~ *.o dots hellmood_memories
+	rm -f *~ *.o dots dots_dump dots_play
diff --git a/utils/gr-sim/dots/dots_dump.c b/utils/gr-sim/dots/dots_dump.c
new file mode 100644
index 00000000..94c08d73
--- /dev/null
+++ b/utils/gr-sim/dots/dots_dump.c
@@ -0,0 +1,920 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <malloc.h>
+#include <math.h>
+
+#include "8086_emulator.h"
+#include "vga_emulator.h"
+
+#include "../gr-sim.h"
+#include "../tfv_zp.h"
+
+#include "sin1024.h"
+
+#define	MAXDOTS	1024
+
+#define BOTTOM 8000
+
+#define SKIP	2
+
+static short gravitybottom=BOTTOM;
+
+static short bpmin=30000;
+static short bpmax=-30000;
+static short gravity=0;
+static short dotnum=0;
+static short gravityd=16;
+
+//???,-1280,-960,-640,-320};
+
+static short rows[200];
+
+//dot dw	MAXDOTS dup(0,0,0,0,0,0,0,0) ;x,y,z,oldposshadow,oldpos,-,-,-
+
+static struct {
+	short	x;	// 0
+	short	y;	// 2
+	short	z;	// 4
+	short	old1;	// 6 oldpos shadow
+	short	old2;	// 8 oldpos
+	short	old3;	// 10
+	short	old4;	// 12
+	short	yadd;	// 14
+} dot[MAXDOTS];
+
+static short rotsin=0;
+static short rotcos=0;
+
+static char *bgpic;
+
+static int depthtable1[128];
+static int depthtable2[128];
+static int depthtable3[128];
+//static int depthtable4[128];
+
+static unsigned char depthtable1_bytes[512];
+static unsigned char depthtable2_bytes[512];
+static unsigned char depthtable3_bytes[512];
+//static unsigned char depthtable4_bytes[512];
+
+
+static void drawdots(void) {
+	int temp32;
+	int yy;
+
+				//	CBEG
+	ax=0xa000;			// mov	ax,0a000h
+	es=ax;				// mov	es,ax
+	ax=cs;				// mov	ax,cs
+	ds=ax;				// mov	ds,ax
+
+	/* why [2]? */
+	fs=bgpic[2];			// mov	fs,cs:_bgpic[2]
+	cx=dotnum;			// mov	cx,cs:_dotnum
+	si=0;				// mov	si,OFFSET dot
+
+label1:
+	push(cx);			// push	cx
+	ax=dot[si].x;			// mov	ax,ds:[si+0] ;X
+	imul_16(rotsin);		// imul	ds:_rotsin
+	ax=ax;				// mov	ax,ax
+	cx=dx;				// mov	cx,dx
+	ax=dot[si].z;			// mov	ax,ds:[si+4] ;Z
+	imul_16(rotcos);		// imul	ds:_rotcos
+	ax=ax-bx;			// sub	ax,bx
+	dx=dx-cx;			// sub	dx,cx
+	bp=dx;				// mov	bp,dx
+	bp=bp+9000;			// add	bp,9000
+
+	ax=dot[si].x;			// mov	ax,ds:[si+0] ;X
+	imul_16(rotcos);		// imul	ds:_rotcos
+	bx=ax;				// mov	bx,ax
+	cx=dx;				// mov	cx,dx
+	ax=dot[si].z;			// mov	ax,ds:[si+4] ;Z
+	imul_16(rotsin);		// imul	ds:_rotsin
+
+	temp32=ax+bx;			// add	ax,bx
+	ax=ax+bx;			//
+	dx=dx+cx;			// adc	dx,cx
+	if (temp32&(1<<16)) dx=dx+1;
+
+
+//	printf("Before: ax=0x%04X dx=%04X\n",ax,dx);
+	ax=(ax>>8)|(dx<<8);		// shrd	ax,dx,8
+	dx=sar(dx,8);			// sar	dx,8
+//	printf("After: ax=0x%04X dx=%04X\n",ax,dx);
+
+	bx=ax;				// mov	bx,ax
+	cx=dx;				// mov	cx,dx
+	ax=(ax>>3)|(dx<<13);		// shrd	ax,dx,3
+
+	dx=sar(dx,3);			// sar	dx,3
+	temp32=ax+bx;			// add	ax,bx
+	ax=ax+bx;
+	dx=dx+cx;			// adc	dx,cx
+	if (temp32&(1<<16)) dx=dx+1;
+
+	temp32=(dx<<16)|(ax&0xfffff);
+	idiv_16(bp);			// idiv bp
+	ax=ax+160;			// add	ax,160
+	push(ax);			// push	ax
+
+	/* if off end of screen, no need for shadow */
+
+	if (ax>319) goto label2;	// cmp	ax,319
+
+					// ja	@@2
+	/**********/
+	/* shadow */
+	/**********/
+
+	ax=0;				// xor	ax,ax
+	dx=8;				// mov	dx,8
+	idiv_16(bp);			// idiv	bp
+	ax=ax+100;			// add	ax,100
+
+	/* if shadow off screen, don't draw */
+	if (ax>199) goto label2;	// cmp	ax,199
+					// ja	@@2
+	bx=ax;				// mov	bx,ax
+
+	// not needed, it's a C array
+	//bx=bx<<1;			// shl	bx,1
+	bx=rows[bx];			// mov	bx,ds:_rows[bx]
+	ax=pop();			// pop	ax
+	bx=bx+ax;			// add	bx,ax
+	push(ax);			// push	ax
+
+//	printf("Drawing shadow at %d,%d\n",bx%320,bx/320);
+
+
+
+	/* erase old shadow (?)*/
+	di=dot[si].old1;		// mov	di,ds:[si+6]
+
+	yy=((di/320)*48)/200;
+	if (yy>23) color_equals(5);
+	else color_equals(0);
+	plot( (di%320)/8,yy);
+
+	//ax=bgpic[di];			// mov	ax,fs:[di]
+	//framebuffer[di]=ax;		// mov	es:[di],ax
+
+//	framebuffer[di]=bgpic[di];
+//	framebuffer[di+1]=bgpic[di+1];
+	framebuffer_write(di,bgpic[di]);
+	framebuffer_write(di+1,bgpic[di+1]);
+
+
+
+	/* draw new shadow (?) */
+//	ax=87+87*256;			// mov	ax,87+87*256
+//	framebuffer[bx]=ax;		// mov	word ptr es:[bx],ax
+
+//	framebuffer[bx]=87;
+//	framebuffer[bx+1]=87;
+	framebuffer_write(bx,87);
+	framebuffer_write(bx+1,87);
+
+//	bx/320 -> 200     200->48  *48/200
+
+	yy=((bx/320)*48)/200;
+	color_equals(0);
+	plot( (bx%320)/8,yy);
+//	printf("0,%d,%d\n",(bx%320)/8,yy);
+
+//	printf("Plotting at %d,%d\n",(bx%320)/8,(bx/320)/5);
+
+	/* save this to erase next time */
+	dot[si].old1=bx;		// mov	ds:[si+6],bx
+
+	/********/
+	/* ball */
+	/********/
+//	ax=gravity;			// mov	ax,ds:_gravity
+//	dot[si].yadd+=ax;		// add	ds:[si+14],ax
+
+//	if (si==100) printf("Gravity: %hd (%04x)  Yadd: %hd (%04x)\n",
+//			gravity,gravity,dot[si].yadd,dot[si].yadd);
+
+	dot[si].yadd+=gravity;
+
+//	if (si==100) printf("\tyadd after yadd+=gravity: %hd (%04x)\n",
+//			dot[si].yadd,dot[si].yadd);
+
+//	ax=dot[si].y;			// mov	ax,ds:[si+2] ;Y
+//	ax+=dot[si].yadd;		// add	ax,ds:[si+14]
+	ax=dot[si].y+dot[si].yadd;
+
+//	if (si==100) printf("\tax=y+yadd: %hu (%04x) = "
+//			"%hd (%04x) + %hd (%04x)\n",
+//			ax,ax,dot[si].y,dot[si].y,dot[si].yadd,dot[si].yadd);
+
+//	if (si==100) printf("\tcomparing if (ax<gravitybottom): "
+//			"%hu < %hd\n",ax,gravitybottom);
+
+
+	temp32=ax;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32<gravitybottom) goto label4; //cmp	ax,ds:_gravitybottom
+					// jl	@@4
+
+//	if (si==100) printf("\twas greater than (not less)\n");
+
+	push(ax);			// push	ax
+
+//	ax=dot[si].yadd;		// mov	ax,ds:[si+14]
+//	ax=-ax;				// neg	ax
+	ax=-dot[si].yadd;
+
+//	if (si==100) printf("\tax is -yadd: %hu %x\n",ax,ax);
+
+//	if (si==100) printf("\tabout to multiply gravityd*ax: "
+//			"%hd (%x) * %hu (%x)\n",gravityd,gravityd,
+//			ax,ax);
+	imul_16(gravityd);		// imul	cs:_gravityd
+
+//	if (si==100) printf("\tresult dx:ax is %x:%x (%hu)\n",
+//			dx,ax,ax);
+
+	ax=sar(ax,4);			// sar	ax,4
+
+//	if (si==100) printf("\tyadd=(ax>>4 is %x (%hu))\n",
+//			ax,ax);
+	dot[si].yadd=ax;		// mov	ds:[si+14],ax
+	ax=pop();			// pop	ax
+//	if (si==100) printf("\trestoring ax=%x, adding yadd %x\n",
+//		ax,dot[si].yadd);
+
+	ax+=dot[si].yadd;		// add	ax,ds:[si+14]
+
+//	if (si==100) printf("\tax=%x\n",ax);
+
+label4:
+	dot[si].y=ax;			// mov	ds:[si+2],ax
+
+//	if (si==100) printf("\tdot[si].y=%x\n",dot[si].y);
+
+	if (ax&0x8000) {		// cwd
+		dx=0xffff;
+	}
+	else {
+		dx=0;
+	}
+
+//	if (si==100) printf("\tdx:ax = %04hx:%04hx\n",dx,ax);
+
+	dx=(dx<<6)|(ax>>10);		// shld	dx,ax,6
+	ax=ax<<6;			// shl	ax,6
+
+//	if (si==100) printf("\tdx:ax <<6 = %04hx:%04hx, bp=%04hx\n",dx,ax,bp);
+
+	idiv_16(bp);			// idiv	bp
+//	if (si==100) printf("\tY ax=%d\n",ax);
+	ax=ax+100;			// add	ax,100
+	if (ax>199) goto label3;	// cmp	ax,199
+					// ja	@@3
+//	if (si==100) printf("\tdraw Y ax=%d\n",ax);
+	bx=ax;				// mov	bx,ax
+
+	// not needed, C array
+	//bx=bx<<1;			// shl	bx,1
+	bx=rows[bx];			// mov	bx,ds:_rows[bx]
+
+	ax=pop();			// pop	ax
+	bx=bx+ax;			// add	bx,ax
+
+	di=dot[si].old2;		// mov	di,ds:[si+8]
+//	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+//	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+//	framebuffer[di+2]=bgpic[di+2];
+//	framebuffer[di+3]=bgpic[di+3];
+
+	yy=((di/320)*48)/200;
+	if (yy>23) color_equals(5);
+	else color_equals(0);
+	plot( (di%320)/8,yy);
+
+	framebuffer_write(di,bgpic[di]);
+	framebuffer_write(di+1,bgpic[di+1]);
+	framebuffer_write(di+2,bgpic[di+2]);
+	framebuffer_write(di+3,bgpic[di+3]);
+
+
+
+
+	di=di+320;			// add	di,320
+//	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+//	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+//	framebuffer[di+2]=bgpic[di+2];
+//	framebuffer[di+3]=bgpic[di+3];
+
+	framebuffer_write(di,bgpic[di]);
+	framebuffer_write(di+1,bgpic[di+1]);
+	framebuffer_write(di+2,bgpic[di+2]);
+	framebuffer_write(di+3,bgpic[di+3]);
+
+
+	di=di+320;			// add	di,320
+//	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+//	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+//	framebuffer[di+2]=bgpic[di+2];
+//	framebuffer[di+3]=bgpic[di+3];
+
+	framebuffer_write(di,bgpic[di]);
+	framebuffer_write(di+1,bgpic[di+1]);
+	framebuffer_write(di+2,bgpic[di+2]);
+	framebuffer_write(di+3,bgpic[di+3]);
+
+				//;;	add	di,320
+				//;;	mov	eax,fs:[di]
+				//;;	mov	es:[di],eax
+
+	bp=bp>>6;		// shr	bp,6
+	bp=bp&(~3L);		// and	bp,not 3
+
+	temp32=bp;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32>=bpmin) goto label_t1;	// cmp	bp,cs:_bpmin
+					// jge	@@t1
+	bpmin=bp;			// mov	cs:_bpmin,bp
+label_t1:
+	temp32=bp;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32<=bpmax) goto label_t2;	// cmp	bp,cs:_bpmax
+					// jle	@@t2
+	bpmax=bp;			// mov	cs:_bpmax,bp
+label_t2:
+//	eax=depthtable1[bp];		// mov	ax,word ptr ds:_depthtable1[bp]
+					// mov	word ptr es:[bx+1],ax
+
+
+	yy=((bx/320)*48)/200;
+	color_equals(6);
+	plot( (bx%320)/8,yy);
+//	printf("6,%d,%d\n",(bx%320)/8,yy);
+
+	framebuffer[bx+1]=depthtable1_bytes[bp];
+	framebuffer[bx+2]=depthtable1_bytes[bp+1];
+
+	//eax=depthtable2[bp];		// mov	eax,ds:_depthtable2[bp]
+					// mov	dword ptr es:[bx+320],eax
+	framebuffer[bx+320]=depthtable2_bytes[bp];
+	framebuffer[bx+321]=depthtable2_bytes[bp+1];
+	framebuffer[bx+322]=depthtable2_bytes[bp+2];
+	framebuffer[bx+323]=depthtable2_bytes[bp+3];
+
+//	eax=depthtable3[bp];	// mov	ax,word ptr ds:_depthtable3[bp]
+				// mov	word ptr es:[bx+641],ax
+	framebuffer[bx+641]=depthtable3_bytes[bp];
+	framebuffer[bx+642]=depthtable3_bytes[bp+1];
+	dot[si].old2=bx;	// mov	ds:[si+8],bx
+
+
+//labelz:
+	cx=pop();		// pop	cx
+	si=si+SKIP;		// add	si,16	point to next dot
+	cx=cx-SKIP;
+	if (cx!=0) goto label1;	// loop	@@1
+label0:
+	return;
+				// @@0:	CEND
+
+label2:
+	/* This is called when we are off the screen */
+	/* erases old but didn't draw new */
+
+	/* erase old dot */
+	di=dot[si].old2;		// mov	di,ds:[si+8]
+
+
+	yy=((di/320)*48)/200;
+	if (yy>23) color_equals(5);
+	else color_equals(0);
+	plot( (di%320)/8,yy);
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	di=di+320;			// add	di,320
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	di=di+320;			// add  di,320
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	ax=(framebuffer[di]|(framebuffer[di+1]<<8));
+
+	/* doing something to shadow here? */
+
+	di=dot[si].old1;		// mov	di,ds:[si+6]
+	dot[si].old1=ax;		// mov	ds:[si+6],ax
+
+	framebuffer[di]=bgpic[di];	// mov	ax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],ax
+
+	bx=pop();			// pop	bx
+	cx=pop();			// pop	cx
+	si=si+SKIP;			// add	si,16
+	cx=cx-SKIP;			// loop	@@1
+	if (cx!=0) goto label1;
+	goto label0;			// jmp	@@0
+
+label3:
+	/* erase old dot */
+	di=dot[si].old2;		// mov	di,ds:[si+8]
+
+	yy=((di/320)*48)/200;
+	if (yy>23) color_equals(5);
+	else color_equals(0);
+	plot( (di%320)/8,yy);
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	di=di+320;			// add	di,320
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	di=di+320;			// add	di,320
+
+	framebuffer[di]=bgpic[di];	// mov	eax,fs:[di]
+	framebuffer[di+1]=bgpic[di+1];	// mov	es:[di],eax
+	framebuffer[di+2]=bgpic[di+2];
+	framebuffer[di+3]=bgpic[di+3];
+
+	bx=pop();			// pop	bx
+	cx=pop();			// pop	cx
+	si=si+SKIP;			// add	si,16
+	cx=cx-SKIP;			// loop	@@1
+	if (cx!=0) goto label1;
+	goto label0;			// jmp	@@0
+
+}
+
+static void setpalette(char *pal) {
+
+	int c;
+
+	// push	bp
+	// mov	bp,sp
+	// push	si
+	// push	di
+	// push	ds
+	// mov	si,[bp+6]
+	// mov	ds,[bp+8]
+					// mov	dx,3c8h
+					// mov	al,0
+	outp(0x3c8,0);			//out	dx,al
+
+	for(c=0;c<768;c++) outp(0x3c9,pal[c]);
+	grsim_update();
+					// inc	dx
+					//mov	cx,768
+					//rep	outsb
+					//	pop	ds
+					//	pop	di
+					//	pop	si
+					//	pop	bp
+					//	ret
+
+}
+
+//short face[]={
+//	2248,-2306,0,		// from face.inc
+//	30000,30000,30000
+//};
+
+/* wait for VGA border start */
+static short dis_waitb(void) {
+
+// descr: Waits for border start
+// waitb_1 PROC NEAR
+//        call    checkkeys
+
+//        IFDEF INDEMO
+//        sti
+//        mov     ax,cs:copperframecount
+//@@v:    cmp     cs:copperframecount,ax
+//        je      @@v
+//@@q:    mov     ax,cs:copperframecount
+//       mov     cs:copperframecount,0
+//        ELSE
+
+//        mov     dx,3dah
+//@@1:    in      al,dx
+//        test    al,8
+//        jnz     @@1
+//@@2:    in      al,dx
+//        test    al,8
+ //       jz      @@2
+
+  //      mov     ax,1 ;number of frames taken            ;TEMP!
+
+//        ENDIF
+//        ret
+//waitb_1 ENDP
+
+
+	/* approximate by 70Hz sleep */
+	usleep(14286);
+
+	return 1;
+}
+
+static short dis_exit(void) {
+	return 0;
+}
+
+static short dis_indemo(void) {
+	return 0;
+}
+
+//char far *vram=(char far *)0xa0000000L;
+static unsigned char *vram=framebuffer;
+
+static char pal[768];
+static char pal2[768];
+
+static short isin(short deg) {
+	return(sin1024[deg&1023]);
+}
+
+static short icos(short deg) {
+	return(sin1024[(deg+256)&1023]);
+}
+
+static void setborder(short color) {
+
+	//printf("Setting border to %d\n",color);
+
+	// to write attribute register:
+	//	read/write address to $3c0
+	//	data written to $3c0, read from $3c1
+	// flip flop tracks if it's index/data, you reset that
+	//	by reading $3da
+
+	//mov	dx,3dah			// input status reg #1
+	//in	al,dx			// resets index/addr flip-flop
+
+	//mov	dx,3c0h			// attribute access
+	//mov	al,11h+32		// $11=overscan (border color)
+					// 32 is PAS bit
+	//out	dx,al
+
+	//mov	al,color
+	//out	dx,al
+}
+
+static short cols[]={
+0,0,0,
+4,25,30,
+8,40,45,
+16,55,60};
+
+static short dottaul[1024];
+
+int main(int argc,char **argv) {
+
+//	short timer=30000;
+	short dropper,repeat;
+	short frame=0;
+	short rota=-1*64;
+//	short fb=0;
+	short rot=0,rots=0;
+	short a,b,c,d,i,j=0;//,mode;
+	short grav,gravd;
+	short f=0;
+	int ch;
+
+	//dis_partstart();
+
+	dotnum=512;
+	for(a=0;a<dotnum;a++) {
+		dottaul[a]=a;
+	}
+
+	for(a=0;a<500;a++) {
+		b=rand()%dotnum;
+		c=rand()%dotnum;
+		d=dottaul[b];
+		dottaul[b]=dottaul[c];
+		dottaul[c]=d;
+	}
+
+	dropper=22000;
+
+	for(a=0;a<dotnum;a++) {
+		dot[a].x=0;
+		dot[a].y=2560-dropper;
+		dot[a].z=0;
+		dot[a].yadd=0;
+	}
+	//mode=7;
+	grav=3;
+	gravd=13;
+	gravitybottom=8105;
+	i=-1;
+
+	for(a=0;a<500;a++) { // scramble
+		b=rand()%dotnum;
+		c=rand()%dotnum;
+		d=dot[b].x; dot[b].x=dot[c].x; dot[c].x=d;
+		d=dot[b].y; dot[b].y=dot[c].y; dot[c].y=d;
+		d=dot[b].z; dot[b].z=dot[c].z; dot[c].z=d;
+	}
+
+	/* setup rows lookup table */
+	for(a=0;a<200;a++) {
+		rows[a]=a*320;
+	}
+
+//	set_default_pal();
+
+//	mode13h_graphics_init("dots",2);
+
+	grsim_init();
+
+	gr();
+
+	clear_screens();
+	soft_switch(MIXCLR);
+
+	ram[DRAW_PAGE]=0;
+
+	color_equals(5);
+	for(a=24;a<48;a++) hlin(0,0,40,a);
+
+
+//	set mode 13h
+//	_asm mov ax,13h
+//	_asm int 10h
+
+	/* set palette address to 0 */
+	outp(0x3c8,0);
+
+	/* set up colors for first 64 colors */
+	for(a=0;a<16;a++) {
+		for(b=0;b<4;b++) {
+			c=100+a*9;
+			outp(0x3c9,cols[b*3+0]);
+			outp(0x3c9,cols[b*3+1]*c/256);
+			outp(0x3c9,cols[b*3+2]*c/256);
+		}
+	}
+
+	/* set palette for color 255 */
+	outp(0x3c8,255);
+
+	/* some sort of purplish color? */
+	outp(0x3c9,31);
+	outp(0x3c9,0);
+	outp(0x3c9,15);
+
+
+	/* set colors starting from 64 ... 164 */
+	/* looks like a grey gradient of some sort */
+	outp(0x3c8,64);
+
+	for(a=0;a<100;a++) {
+		c=64-256/(a+4);
+		c=c*c/64;
+		outp(0x3c9,c/4);
+		outp(0x3c9,c/4);
+		outp(0x3c9,c/4);
+	}
+
+	/* read out the VGA card's idea of palette (?) */
+	outp(0x3c7,0);
+	for(a=0;a<768;a++) pal[a]=inp(0x3c9);
+
+	/* clear palette to all 0 */
+	/* this lets up setup background while not visible */
+	outp(0x3c8,0);
+	for(a=0;a<768;a++) outp(0x3c9,0);
+
+	/* put grey gradient on bottom half of screen? */
+	for(a=0;a<100;a++) {
+		memset(vram+(100+a)*320,a+64,320);
+	}
+
+	/* set up depth table? */
+	/* this has further away balls a darker color */
+	for(a=0;a<128;a++) {
+		c=a-(43+20)/2;
+		c=c*3/4;
+		c+=8;
+		if(c<0) c=0; else if(c>15) c=15;
+		c=15-c;
+		depthtable1[a]=0x202+0x04040404*c;
+		depthtable2[a]=0x02030302+0x04040404*c;
+		depthtable3[a]=0x202+0x04040404*c;
+		//depthtable4[a]=0x02020302+0x04040404*c;
+	}
+
+	/* make a byte-wise copy of this */
+	/* the original code just indexes byte-wise into integer data */
+	/* which is a pain */
+	for(a=0;a<128;a++) {
+		depthtable1_bytes[(a*4)+0]=(depthtable1[a]>>0)&0xff;
+		depthtable1_bytes[(a*4)+1]=(depthtable1[a]>>8)&0xff;
+		depthtable1_bytes[(a*4)+2]=(depthtable1[a]>>16)&0xff;
+		depthtable1_bytes[(a*4)+3]=(depthtable1[a]>>24)&0xff;
+
+		depthtable2_bytes[(a*4)+0]=(depthtable2[a]>>0)&0xff;
+		depthtable2_bytes[(a*4)+1]=(depthtable2[a]>>8)&0xff;
+		depthtable2_bytes[(a*4)+2]=(depthtable2[a]>>16)&0xff;
+		depthtable2_bytes[(a*4)+3]=(depthtable2[a]>>24)&0xff;
+
+		depthtable3_bytes[(a*4)+0]=(depthtable3[a]>>0)&0xff;
+		depthtable3_bytes[(a*4)+1]=(depthtable3[a]>>8)&0xff;
+		depthtable3_bytes[(a*4)+2]=(depthtable3[a]>>16)&0xff;
+		depthtable3_bytes[(a*4)+3]=(depthtable3[a]>>24)&0xff;
+
+
+
+	}
+
+
+	/* allocate space for background */
+	//bgpic=halloc(64000L,1L);
+	bgpic=calloc(65536L,1L);
+
+	/* backup background */
+	memcpy(bgpic,vram,64000);
+
+	grsim_update();
+
+	/* Fade back in from black to palette */
+	a=0;
+	for(b=64;b>=0;b--) {
+		for(c=0;c<768;c++) {
+			a=pal[c]-b;
+			if(a<0) a=0;
+			pal2[c]=a;
+		}
+		/* wait for retrace (delay) */
+		dis_waitb();
+		dis_waitb();
+		outp(0x3c8,0);
+		for(c=0;c<768;c++) outp(0x3c9,pal2[c]);
+		grsim_update();
+	}
+
+	while(!dis_exit() && frame<2450) {
+
+		/* code sets border color */
+		/* then waits for it to end, as a timing thing? */
+		setborder(0);
+
+		/* when not in demo this defaults to 1? */
+		repeat=dis_waitb();
+
+		if(frame>2300) setpalette(pal2);
+
+		setborder(1);
+
+		if(dis_indemo()) {
+			/* ?? music synchronization? */
+//			a=dis_musplus();
+//			if(a>-4 && a<0) break;
+		}
+
+		repeat=1;
+
+		while(repeat--) {
+
+		frame++;
+		if(frame==500) f=0;
+		i=dottaul[j];
+		j++; j%=dotnum;
+
+		/* initial spin */
+		if(frame<500) {
+			dot[i].x=isin(f*11)*40;
+			dot[i].y=icos(f*13)*10-dropper;
+			dot[i].z=isin(f*17)*40;
+			dot[i].yadd=0;
+//			printf("%d: %d,%d,%d,%d\n",i,
+//				dot[i].x,dot[i].y,dot[i].z,dot[i].yadd);
+		}
+		/* bouncing ring */
+		else if(frame<900) {
+			dot[i].x=icos(f*15)*55;
+			dot[i].y=dropper;
+			dot[i].z=isin(f*15)*55;
+			dot[i].yadd=-260;
+		}
+		/* fountain */
+		else if(frame<1700) {
+			a=sin1024[frame&1023]/8;
+			dot[i].x=icos(f*66)*a;
+			dot[i].y=8000;
+			dot[i].z=isin(f*66)*a;
+			dot[i].yadd=-300;
+		}
+		/* swirling */
+		else if(frame<2360) {
+				/*
+				a=rand()/128+32;
+				dot[i].y=8000-a*80;
+				b=rand()&1023;
+				a+=rand()&31;
+				dot[i].x=sin1024[b]*a/3+(a-50)*7;
+				dot[i].z=sin1024[(b+256)&1023]*a/3+(a-40)*7;
+				dot[i].yadd=300;
+				if(frame>1640 && !(frame&31) && grav>-2) grav--;
+				*/
+			dot[i].x=rand()-16384;
+			dot[i].y=8000-rand()/2;
+			dot[i].z=rand()-16384;
+			dot[i].yadd=0;
+			if(frame>1900 && !(frame&31) && grav>0) grav--;
+		}
+		/* palette to white */
+		else if(frame<2400) {
+			a=frame-2360;
+			for(b=0;b<768;b+=3) {
+				c=pal[b+0]+a*3;
+				if(c>63) c=63;
+				pal2[b+0]=c;
+				c=pal[b+1]+a*3;
+				if(c>63) c=63;
+				pal2[b+1]=c;
+				c=pal[b+2]+a*4;
+				if(c>63) c=63;
+				pal2[b+2]=c;
+			}
+		}
+		/* palette to black */
+		else if(frame<2440) {
+			a=frame-2400;
+			for(b=0;b<768;b+=3) {
+				c=63-a*2;
+				if(c<0) c=0;
+				pal2[b+0]=c;
+				pal2[b+1]=c;
+				pal2[b+2]=c;
+			}
+		}
+		if(dropper>4000) dropper-=100;
+
+		rotcos=icos(rot)*64; rotsin=isin(rot)*64;
+		rots+=2;
+
+		if(frame>1900) {
+			rot+=rota/64;
+			rota--;
+		}
+		else rot=isin(rots);
+
+		f++;
+		gravity=grav;
+		gravityd=gravd;
+
+		}
+
+
+		drawdots();
+
+		grsim_update();
+
+#if 0
+		for(i=0;i<dotnum;i++) {
+			printf("%d: %d,%d,%d  %d\n",i,
+				dot[i].x,dot[i].y,dot[i].z,dot[i].yadd);
+		}
+#endif
+
+again:
+		ch=grsim_input();
+		if (ch==27) {
+			return 0;
+		}
+//		else if (ch==0) goto again;
+
+	}
+
+//	restores 80x25 color text mode
+//	if (!dis_indemo()) {
+//		_asm mov ax,3h
+//		_asm int 10h
+//	}
+	return 0;
+}
diff --git a/utils/gr-sim/dots/dots_minimal.c b/utils/gr-sim/dots/dots_minimal.c
new file mode 100644
index 00000000..07c17ad2
--- /dev/null
+++ b/utils/gr-sim/dots/dots_minimal.c
@@ -0,0 +1,400 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <malloc.h>
+#include <math.h>
+
+#include "8086_emulator.h"
+#include "vga_emulator.h"
+
+#include "../gr-sim.h"
+#include "../tfv_zp.h"
+
+#include "sin1024.h"
+
+#define	MAXDOTS	1024
+
+#define SKIP	2
+
+static short gravitybottom;
+static short bpmin=30000;
+static short bpmax=-30000;
+static short gravity=0;
+static short dotnum=0;
+static short gravityd=16;
+
+static short rows[200];
+
+static struct {
+	short	x;	// 0
+	short	y;	// 2
+	short	z;	// 4
+	short	old1;	// 6 oldpos shadow
+	short	old2;	// 8 oldpos
+	short	old3;	// 10
+	short	old4;	// 12
+	short	yadd;	// 14
+} dot[MAXDOTS];
+
+static short rotsin=0;
+static short rotcos=0;
+
+static void drawdots(void) {
+	int temp32;
+	int yy;
+
+	cx=dotnum;			// mov	cx,cs:_dotnum
+	si=0;				// mov	si,OFFSET dot
+
+label1:
+	push(cx);			// push	cx
+	ax=dot[si].x;			// mov	ax,ds:[si+0] ;X
+	imul_16(rotsin);		// imul	ds:_rotsin
+	ax=ax;				// mov	ax,ax
+	cx=dx;				// mov	cx,dx
+	ax=dot[si].z;			// mov	ax,ds:[si+4] ;Z
+	imul_16(rotcos);		// imul	ds:_rotcos
+	ax=ax-bx;			// sub	ax,bx
+	dx=dx-cx;			// sub	dx,cx
+	bp=dx;				// mov	bp,dx
+	bp=bp+9000;			// add	bp,9000
+
+	ax=dot[si].x;			// mov	ax,ds:[si+0] ;X
+	imul_16(rotcos);		// imul	ds:_rotcos
+	bx=ax;				// mov	bx,ax
+	cx=dx;				// mov	cx,dx
+	ax=dot[si].z;			// mov	ax,ds:[si+4] ;Z
+	imul_16(rotsin);		// imul	ds:_rotsin
+
+	temp32=ax+bx;			// add	ax,bx
+	ax=ax+bx;			//
+	dx=dx+cx;			// adc	dx,cx
+	if (temp32&(1<<16)) dx=dx+1;
+
+	ax=(ax>>8)|(dx<<8);		// shrd	ax,dx,8
+	dx=sar(dx,8);			// sar	dx,8
+
+	bx=ax;				// mov	bx,ax
+	cx=dx;				// mov	cx,dx
+	ax=(ax>>3)|(dx<<13);		// shrd	ax,dx,3
+
+	dx=sar(dx,3);			// sar	dx,3
+	temp32=ax+bx;			// add	ax,bx
+	ax=ax+bx;
+	dx=dx+cx;			// adc	dx,cx
+	if (temp32&(1<<16)) dx=dx+1;
+
+	temp32=(dx<<16)|(ax&0xfffff);
+	idiv_16(bp);			// idiv bp
+	ax=ax+160;			// add	ax,160
+	push(ax);			// push	ax
+
+	/* if off end of screen, no need for shadow */
+
+	if (ax>319) goto label2;	// cmp	ax,319
+
+					// ja	@@2
+	/**********/
+	/* shadow */
+	/**********/
+
+	ax=0;				// xor	ax,ax
+	dx=8;				// mov	dx,8
+	idiv_16(bp);			// idiv	bp
+	ax=ax+100;			// add	ax,100
+
+	/* if shadow off screen, don't draw */
+	if (ax>199) goto label2;	// cmp	ax,199
+					// ja	@@2
+	bx=ax;				// mov	bx,ax
+
+	// not needed, it's a C array
+	//bx=bx<<1;			// shl	bx,1
+	bx=rows[bx];			// mov	bx,ds:_rows[bx]
+	ax=pop();			// pop	ax
+	bx=bx+ax;			// add	bx,ax
+	push(ax);			// push	ax
+
+
+	/* draw new shadow (?) */
+
+//	bx/320 -> 200     200->48  *48/200
+
+	yy=((bx/320)*48)/200;
+	color_equals(0);
+	plot( (bx%320)/8,yy);
+
+	/********/
+	/* ball */
+	/********/
+
+	dot[si].yadd+=gravity;
+	ax=dot[si].y+dot[si].yadd;
+
+	temp32=ax;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32<gravitybottom) goto label4; //cmp	ax,ds:_gravitybottom
+					// jl	@@4
+
+	push(ax);			// push	ax
+	ax=-dot[si].yadd;
+	imul_16(gravityd);		// imul	cs:_gravityd
+	ax=sar(ax,4);			// sar	ax,4
+	dot[si].yadd=ax;		// mov	ds:[si+14],ax
+	ax=pop();			// pop	ax
+	ax+=dot[si].yadd;		// add	ax,ds:[si+14]
+
+label4:
+	dot[si].y=ax;			// mov	ds:[si+2],ax
+	if (ax&0x8000) {		// cwd
+		dx=0xffff;
+	}
+	else {
+		dx=0;
+	}
+	dx=(dx<<6)|(ax>>10);		// shld	dx,ax,6
+	ax=ax<<6;			// shl	ax,6
+	idiv_16(bp);			// idiv	bp
+	ax=ax+100;			// add	ax,100
+	if (ax>199) goto label3;	// cmp	ax,199
+					// ja	@@3
+	bx=ax;				// mov	bx,ax
+
+	// not needed, C array
+	//bx=bx<<1;			// shl	bx,1
+	bx=rows[bx];			// mov	bx,ds:_rows[bx]
+
+	ax=pop();			// pop	ax
+	bx=bx+ax;			// add	bx,ax
+	bp=bp>>6;		// shr	bp,6
+	bp=bp&(~3L);		// and	bp,not 3
+
+	temp32=bp;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32>=bpmin) goto label_t1;	// cmp	bp,cs:_bpmin
+					// jge	@@t1
+	bpmin=bp;			// mov	cs:_bpmin,bp
+label_t1:
+	temp32=bp;
+	if (temp32&0x8000) temp32|=0xffff0000;
+	if (temp32<=bpmax) goto label_t2;	// cmp	bp,cs:_bpmax
+					// jle	@@t2
+	bpmax=bp;			// mov	cs:_bpmax,bp
+label_t2:
+	yy=((bx/320)*48)/200;
+	color_equals(6);
+	plot( (bx%320)/8,yy);
+	cx=pop();		// pop	cx
+	si=si+SKIP;		// add	si,16	point to next dot
+	cx=cx-SKIP;
+	if (cx!=0) goto label1;	// loop	@@1
+label0:
+	return;
+				// @@0:	CEND
+
+label2:
+	/* This is called when we are off the screen */
+	/* erases old but didn't draw new */
+	bx=pop();			// pop	bx
+	cx=pop();			// pop	cx
+	si=si+SKIP;			// add	si,16
+	cx=cx-SKIP;			// loop	@@1
+	if (cx!=0) goto label1;
+	goto label0;			// jmp	@@0
+
+label3:
+
+	bx=pop();			// pop	bx
+	cx=pop();			// pop	cx
+	si=si+SKIP;			// add	si,16
+	cx=cx-SKIP;			// loop	@@1
+	if (cx!=0) goto label1;
+	goto label0;			// jmp	@@0
+
+}
+
+
+/* wait for VGA border start */
+static short dis_waitb(void) {
+
+	/* approximate by 70Hz sleep */
+	usleep(14286);
+
+	return 1;
+}
+
+
+static char pal[768];
+static char pal2[768];
+
+static short isin(short deg) {
+	return(sin1024[deg&1023]);
+}
+
+static short icos(short deg) {
+	return(sin1024[(deg+256)&1023]);
+}
+
+static short dottaul[1024];
+
+int main(int argc,char **argv) {
+
+	short dropper;
+	short frame=0;
+	short rota=-1*64;
+	short rot=0,rots=0;
+	short a,b,c,d,i,j=0;
+	short grav,gravd;
+	short f=0;
+	int ch;
+
+	dotnum=512;
+	for(a=0;a<dotnum;a++) {
+		dottaul[a]=a;
+	}
+
+	for(a=0;a<500;a++) {
+		b=rand()%dotnum;
+		c=rand()%dotnum;
+		d=dottaul[b];
+		dottaul[b]=dottaul[c];
+		dottaul[c]=d;
+	}
+
+	dropper=22000;
+
+	for(a=0;a<dotnum;a++) {
+		dot[a].x=0;
+		dot[a].y=2560-dropper;
+		dot[a].z=0;
+		dot[a].yadd=0;
+	}
+
+	grav=3;
+	gravd=13;
+	gravitybottom=8105;
+	i=-1;
+
+	for(a=0;a<500;a++) { // scramble
+		b=rand()%dotnum;
+		c=rand()%dotnum;
+		d=dot[b].x; dot[b].x=dot[c].x; dot[c].x=d;
+		d=dot[b].y; dot[b].y=dot[c].y; dot[c].y=d;
+		d=dot[b].z; dot[b].z=dot[c].z; dot[c].z=d;
+	}
+
+	/* setup rows lookup table */
+	for(a=0;a<200;a++) {
+		rows[a]=a*320;
+	}
+
+
+	grsim_init();
+
+	gr();
+
+	clear_screens();
+	soft_switch(MIXCLR);
+
+	ram[DRAW_PAGE]=0;
+
+	while(frame<2450) {
+
+		color_equals(0);
+		for(a=0;a<24;a++) hlin(0,0,40,a);
+		color_equals(5);
+		for(a=24;a<48;a++) hlin(0,0,40,a);
+
+		frame++;
+		if(frame==500) f=0;
+		i=dottaul[j];
+		j++; j%=dotnum;
+
+		/* initial spin */
+		if(frame<500) {
+			dot[i].x=isin(f*11)*40;
+			dot[i].y=icos(f*13)*10-dropper;
+			dot[i].z=isin(f*17)*40;
+			dot[i].yadd=0;
+		}
+		/* bouncing ring */
+		else if(frame<900) {
+			dot[i].x=icos(f*15)*55;
+			dot[i].y=dropper;
+			dot[i].z=isin(f*15)*55;
+			dot[i].yadd=-260;
+		}
+		/* fountain */
+		else if(frame<1700) {
+			a=sin1024[frame&1023]/8;
+			dot[i].x=icos(f*66)*a;
+			dot[i].y=8000;
+			dot[i].z=isin(f*66)*a;
+			dot[i].yadd=-300;
+		}
+		/* swirling */
+		else if(frame<2360) {
+			dot[i].x=rand()-16384;
+			dot[i].y=8000-rand()/2;
+			dot[i].z=rand()-16384;
+			dot[i].yadd=0;
+			if(frame>1900 && !(frame&31) && grav>0) grav--;
+		}
+		/* palette to white */
+		else if(frame<2400) {
+			a=frame-2360;
+			for(b=0;b<768;b+=3) {
+				c=pal[b+0]+a*3;
+				if(c>63) c=63;
+				pal2[b+0]=c;
+				c=pal[b+1]+a*3;
+				if(c>63) c=63;
+				pal2[b+1]=c;
+				c=pal[b+2]+a*4;
+				if(c>63) c=63;
+				pal2[b+2]=c;
+			}
+		}
+		/* palette to black */
+		else if(frame<2440) {
+			a=frame-2400;
+			for(b=0;b<768;b+=3) {
+				c=63-a*2;
+				if(c<0) c=0;
+				pal2[b+0]=c;
+				pal2[b+1]=c;
+				pal2[b+2]=c;
+			}
+		}
+		if(dropper>4000) dropper-=100;
+
+		rotcos=icos(rot)*64; rotsin=isin(rot)*64;
+		rots+=2;
+
+		if(frame>1900) {
+			rot+=rota/64;
+			rota--;
+		}
+		else rot=isin(rots);
+
+		f++;
+		gravity=grav;
+		gravityd=gravd;
+
+
+		drawdots();
+
+		grsim_update();
+
+		dis_waitb();
+
+		ch=grsim_input();
+		if (ch==27) {
+			return 0;
+		}
+
+	}
+
+	return 0;
+}
diff --git a/utils/gr-sim/dots/dots_play.c b/utils/gr-sim/dots/dots_play.c
new file mode 100644
index 00000000..1a4ed699
--- /dev/null
+++ b/utils/gr-sim/dots/dots_play.c
@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <unistd.h>
+
+#include "../gr-sim.h"
+#include "../tfv_zp.h"
+
+int main(int argc, char **argv) {
+
+	int xx,yy,ch;
+	int current_row=0;
+
+	grsim_init();
+
+	gr();
+
+	while(1) {
+		clear_screens();
+		soft_switch(MIXCLR);
+
+		ram[DRAW_PAGE]=0;
+
+        	color_equals(5);
+        	for(yy=24;yy<48;yy++) hlin(0,0,40,yy);
+
+		color_equals(0);
+
+		/* parse loop */
+		while(1) {
+			ch=getchar();
+			if (ch==0xff) break;
+
+			if (ch==0xfe) {
+				color_equals(0);
+				break;
+			}
+			if (ch==0xfd) {
+				color_equals(6);
+				continue;
+			}
+
+			if (ch&0x40) {
+				current_row=ch&0x3f;
+				ch=getchar();
+			}
+			xx=ch;
+			plot(xx,current_row);
+		}
+		if (ch==0xff) break;
+
+		usleep(14285);
+
+		grsim_update();
+
+//again:
+		ch=grsim_input();
+		if (ch==27) {
+			break;
+		}
+//		else if (ch==0) goto again;
+
+	}
+
+	return 0;
+}