dec8.c

这个是延伸mame的在wince平台下的游戏模拟器的代码

/***************************************************************************

Cobra Command:
  Video hardware looks like early version of Bad Dudes, we appear to have
  2 playfields and 1 text layer.  Each playfield has 2 scroll registers and
  4 control bytes:

  Register 1: MSB set is reverse screen (playfield 1 only), always seems to be 2
  Register 2: Unknown, seems to be always 0
  Register 3: Unknown, 3 in foreground, 0 in background (so transparency setting?)
  Register 4: Probably playfield shape, only 2 * 2 supported at moment (1)

  Sprite hardware appears to be the same as Bad Dudes.
  256 colours, palette generated by ram.

The Real Ghostbusters:
1 Deco VSC30 (M60348)
1 Deco HMC20 (M60232)

  1 playfield, same as above, with rowscroll
  1024 colours from 2 proms.
  Sprite hardware close to above, there are some unused (unknown) bits per sprite.

Super Real Darwin:
  1 playfield, x-scroll only
  Closer to earlier Darwin 4078 board than above games.

Last Mission/Shackled:
	Has 1 Deco VSC30 (M60348) (From readme file)
	Has 1 Deco HMC20 (M60232) (From readme file)

	1 playfield
	Sprite hardware same as Karnov.
	(Shackled) Palettes 8-15 for tiles seem to have priority over sprites.

Gondomania:
	Has two large square surface mount chips: [ DRL 40, 8053, 8649a ]
	Has 1 Deco VSC30 (M60348)
	Has 1 Deco HMC20 (M60232)
	Priority - all tiles with *pens* 8-15 appear over sprites with palettes 8-15.

Oscar:
	Uses MXC-06 custom chip for sprites.
	Uses BAC-06 custom chip for background.
	I can't find what makes the fix chars...
	Priority - tiles with palettes 8-15 have their *pens* 8-15 appearing over
sprites.

***************************************************************************/

#include "driver.h"
#include "vidhrdw/generic.h"

static unsigned char *palette_ram,*pf_video,*pf_dirty,*oscar_shared_mem;
static int scroll1[4],scroll2[4],pf1_attr[8],pf2_attr[8];
static struct osd_bitmap *pf1_bitmap,*pf2_bitmap;
unsigned char *dec8_row;

extern int ghost_prot;
static int blank_tile,shackled_priority;

/***************************************************************************

  Convert the color PROMs into a more useable format.

  Real Ghostbusters has two 1024x8 palette PROM.
  I don't know the exact values of the resistors between the RAM and the
  RGB output. I assumed these values (the same as Commando)

  bit 7 -- 220 ohm resistor  -- GREEN
        -- 470 ohm resistor  -- GREEN
        -- 1  kohm resistor  -- GREEN
        -- 2.2kohm resistor  -- GREEN
        -- 220 ohm resistor  -- RED
        -- 470 ohm resistor  -- RED
        -- 1  kohm resistor  -- RED
  bit 0 -- 2.2kohm resistor  -- RED

  bit 7 -- unused
        -- unused
        -- unused
        -- unused
        -- 220 ohm resistor  -- BLUE
        -- 470 ohm resistor  -- BLUE
        -- 1  kohm resistor  -- BLUE
  bit 0 -- 2.2kohm resistor  -- BLUE

***************************************************************************/
void ghostb_vh_convert_color_prom(unsigned char *palette, unsigned short *colortable,const unsigned char *color_prom)
{
	int i;

	for (i = 0;i < Machine->drv->total_colors;i++)
	{
		int bit0,bit1,bit2,bit3;

		bit0 = (color_prom[0] >> 0) & 0x01;
		bit1 = (color_prom[0] >> 1) & 0x01;
		bit2 = (color_prom[0] >> 2) & 0x01;
		bit3 = (color_prom[0] >> 3) & 0x01;
		*(palette++) = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		bit0 = (color_prom[0] >> 4) & 0x01;
		bit1 = (color_prom[0] >> 5) & 0x01;
		bit2 = (color_prom[0] >> 6) & 0x01;
		bit3 = (color_prom[0] >> 7) & 0x01;
		*(palette++) = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		bit0 = (color_prom[Machine->drv->total_colors] >> 0) & 0x01;
		bit1 = (color_prom[Machine->drv->total_colors] >> 1) & 0x01;
		bit2 = (color_prom[Machine->drv->total_colors] >> 2) & 0x01;
		bit3 = (color_prom[Machine->drv->total_colors] >> 3) & 0x01;
		*(palette++) = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		color_prom++;
	}
}

void dec8_pf1_w(int offset, int data)
{
	switch (offset)
	{
  		case 0:
    		case 2:
    		case 4:
    		case 6:
      			pf1_attr[offset]=data;
  	}
}

void dec8_pf2_w(int offset, int data)
{
	switch (offset)
	{
		case 0:
		case 2:
		case 4:
		case 6:
			pf2_attr[offset]=data;
  }
}

void dec8_bac06_0_w(int offset, int data)
{
	switch (offset) {
		case 0:
		case 2:
		case 4:
		case 6:
			pf1_attr[offset]=data;
			break;
		case 0x10: /* Scroll registers */
		case 0x11:
		case 0x12:
		case 0x13:
			scroll1[offset-0x10]=data;
			break;
	}
}

void dec8_bac06_1_w(int offset, int data)
{
	switch (offset) {
		case 0:
		case 2:
		case 4:
		case 6:
			pf2_attr[offset]=data;
			break;
		case 0x10: /* Scroll registers */
		case 0x11:
		case 0x12:
		case 0x13:
			scroll2[offset-0x10]=data;
			break;
	}
}

void dec8_scroll1_w(int offset, int data)
{
	scroll1[offset]=data;
}

void dec8_scroll2_w(int offset, int data)
{
	scroll2[offset]=data;
}

void srdarwin_control_w(int offset, int data)
{
	int bankaddress;
	unsigned char *RAM = Machine->memory_region[0];

	switch (offset) {
    	case 0: /* Top 3 bits - bank switch, bottom 4 - scroll MSB */
			bankaddress = 0x10000 + (data >> 5) * 0x4000;
			cpu_setbank(1,&RAM[bankaddress]);
			scroll2[0]=data&0xf;
			return;

        case 1:
        	scroll2[1]=data;
        	return;
    }
}

void lastmiss_control_w(int offset, int data)
{
	int bankaddress;
	unsigned char *RAM = Machine->memory_region[Machine->drv->cpu[0].memory_region];

	/* Bottom 4 bits - bank switch, Bits 4 & 5 - Scroll MSBs */
	bankaddress = 0x10000 + (data & 0x0f) * 0x4000;
	cpu_setbank(1,&RAM[bankaddress]);

	scroll2[0]=(data>>5)&1;
	scroll2[2]=(data>>6)&1;

if (cpu_getpc()==0xfa51) cpu_reset(1); /* No way this can be right... */
if (cpu_getpc()==0xf9d2) cpu_reset(1); /* No way this can be right... */


}

void lastmiss_scrollx_w(int offset, int data)
{
	scroll2[1]=data;
}

void lastmiss_scrolly_w(int offset, int data)
{
	scroll2[3]=data;
}

void gondo_scroll_w(int offset, int data)
{
	switch (offset) {
		case 0x0: scroll2[1]=data; break; 
		case 0x8: scroll2[3]=data; break;
		case 0x10:  scroll2[0]=data;break;
	}
}

/******************************************************************************/

/* 'Karnov' sprites, used by Gondomania, Last Mission, Shackled, Ghostbusters */
static void draw_sprites1(struct osd_bitmap *bitmap, int priority)
{
	int offs,x,y,sprite,sprite2,colour,extra,fx,fy,inc;

	for (offs = 0;offs < 0x800;offs += 8)
	{
		y=spriteram[offs+1]+(spriteram[offs]<<8);
		if ((y&0x8000) == 0) continue;

        fx=spriteram[offs+3];

		if ((fx&0x1) == 0) continue;

		extra=fx&0x10;
        fy=fx&0x2;
        fx=fx&0x4;

		x = spriteram[offs+5]+(spriteram[offs+4]<<8);
		colour = spriteram[offs+6] >> 4;
		if (priority==1 && (colour&8)) continue;
		if (priority==2 && !(colour&8)) continue;
		sprite = spriteram[offs+7]+(spriteram[offs+6]<<8);
		sprite &= 0x0fff;

		if (extra) {y=y+16;sprite&=0xffe;}

		x = x & 0x01ff;
		y = y & 0x01ff;
		x=(x+16)%0x200;
		y=(y+16)%0x200;
		x=256 - x;
		y=256 - y;

		/* Y Flip determines order of multi-sprite */
		if (extra && fy) {
			sprite2=sprite;
			sprite++;
		}
		else sprite2=sprite+1;

		drawgfx(bitmap,Machine->gfx[1],
				sprite,
				colour,fx,fy,x,y,
				0,TRANSPARENCY_PEN,0);

    	/* 1 more sprite drawn underneath */
    	if (extra)
    		drawgfx(bitmap,Machine->gfx[1],
				sprite2,
				colour,fx,fy,x,y+16,
				0,TRANSPARENCY_PEN,0);
	}
}

/* 'Dec0' sprites, used by Cobra Command, Oscar */
static void draw_sprites2(struct osd_bitmap *bitmap, int priority)
{
	int offs;

	/* Sprites */
	for (offs = 0;offs < 0x800;offs += 8)
	{
		int x,y,sprite,colour,multi,fx,fy,inc;

		y =spriteram[offs+1]+(spriteram[offs]<<8);
 		if ((y&0x8000) == 0) continue;
		x = spriteram[offs+5]+(spriteram[offs+4]<<8);
		colour = ((x & 0xf000) >> 12);

		if (priority==1 &&  (colour&8)) continue;
		if (priority==2 && !(colour&8)) continue;


		fx = y & 0x2000;
		fy = y & 0x4000;
		multi = (1 << ((y & 0x1800) >> 11)) - 1;	/* 1x, 2x, 4x, 8x height */

											/* multi = 0   1   3   7 */
		sprite = spriteram[offs+3]+(spriteram[offs+2]<<8);
		sprite &= 0x0fff;

		x = x & 0x01ff;
		y = y & 0x01ff;
		if (x >= 256) x -= 512;
		if (y >= 256) y -= 512;
		x = 240 - x;
		y = 240 - y;

		sprite &= ~multi;
		if (fy)
			inc = -1;
		else
		{
			sprite += multi;
			inc = 1;
		}

		while (multi >= 0)
		{
			drawgfx(bitmap,Machine->gfx[1],
					sprite - multi * inc,
					colour,
					fx,fy,
					x,y - 16 * multi,
					&Machine->drv->visible_area,TRANSPARENCY_PEN,0);
			multi--;
		}
	}
}

/* Draw character tiles, each game has different colour masks */
static void draw_characters(struct osd_bitmap *bitmap, int mask, int shift)
{
	int mx,my,tile,color,offs;


	for (offs = 0x800 - 2;offs >= 0;offs -= 2) {
		tile=videoram[offs+1]+((videoram[offs]&0xf)<<8);

		
		if (!tile) continue;

		color=(videoram[offs]&mask)>>shift;
		mx = (offs/2) % 32;
		my = (offs/2) / 32;

		drawgfx(bitmap,Machine->gfx[0],
				tile,color,0,0,8*mx,8*my,
				&Machine->drv->visible_area,TRANSPARENCY_PEN,0);
	}
}

/******************************************************************************/

void dec8_vh_screenrefresh(struct osd_bitmap *bitmap, int full_refresh)
{
	int my,mx,offs,color,tile;
	int scrollx,scrolly;

	if (palette_recalc())
    	memset(pf_dirty,1,0x800);

	/* Playfield 2 - Foreground */
	mx=-1; my=0;
	for (offs = 0x000;offs < 0x400; offs += 2) {
		mx++;
		if (mx==16) {mx=0; my++;}
		if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;
		tile=pf_video[offs+1]+(pf_video[offs]<<8);
		color = ((tile & 0xf000) >> 12);
        tile=tile&0xfff;

		drawgfx(pf2_bitmap,Machine->gfx[2],tile,
			color, 0,0, 16*mx,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

	mx=-1; my=0;
	for (offs = 0x400;offs < 0x800; offs += 2) {
	    mx++;
	    if (mx==16) {mx=0; my++;}
	    if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;
	    tile=pf_video[offs+1]+(pf_video[offs]<<8);
	    color = ((tile & 0xf000) >> 12);
	    tile=tile&0xfff;
		drawgfx(pf2_bitmap,Machine->gfx[2],tile,
			color, 0,0, (16*mx)+256,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

  /* Playfield 1 */
  mx=-1; my=0;
  for (offs = 0x800;offs < 0xc00; offs += 2) {
    mx++;
    if (mx==16) {mx=0; my++;}
    if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;
    tile=pf_video[offs+1]+(pf_video[offs]<<8);
    color = ((tile & 0xf000) >> 12);
    tile=tile&0xfff;
		drawgfx(pf1_bitmap,Machine->gfx[3],tile,
			color, 0,0, 16*mx,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

  mx=-1; my=0;
  for (offs = 0xc00;offs < 0x1000; offs += 2) {
    mx++;
    if (mx==16) {mx=0; my++;}
    if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;
    tile=pf_video[offs+1]+(pf_video[offs]<<8);
    color = ((tile & 0xf000) >> 12);
    tile=tile&0xfff;
		drawgfx(pf1_bitmap,Machine->gfx[3],tile,
			color, 0,0, (16*mx)+256,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

  scrolly=-((scroll1[2]<<8)+scroll1[3]);
  scrollx=-((scroll1[0]<<8)+scroll1[1]);
 


	scrolly=-((scroll2[2]<<8)+scroll2[3]);
	scrollx=-(((scroll2[0]&1)<<8)+scroll2[1]);
	copyscrollbitmap(bitmap,pf2_bitmap,1,&scrollx,1,&scrolly,0,TRANSPARENCY_NONE,0);

	/* Sprites */
	draw_sprites2(bitmap,0);

	/* Top layer */
	draw_characters(bitmap,0x70,4);

}

void ghostb_vh_screenrefresh(struct osd_bitmap *bitmap, int full_refresh)
{
	int my,mx,offs,color,tile;
	int scrollx,scrolly,fx,fy;

	/* Playfield */
	mx=-1; my=0;
	for (offs = 0x000;offs < 0x400; offs += 2) {
		mx++;
    	if (mx==16) {mx=0; my++;}
		if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;

    	tile=pf_video[offs+1]+(pf_video[offs]<<8);
    	color = ((tile & 0xf000) >> 12);
    	tile=tile&0xfff;
		drawgfx(pf2_bitmap,Machine->gfx[2],tile,
			color, 0, 0, 16*mx,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

	mx=-1; my=0;
	for (offs = 0x400;offs < 0x800; offs += 2) {
    	mx++;
    	if (mx==16) {mx=0; my++;}
    	if (!pf_dirty[offs/2]) continue; else pf_dirty[offs/2]=0;

	    tile=pf_video[offs+1]+(pf_video[offs]<<8);
	    color = ((tile & 0xf000) >> 12);
	    tile=tile&0xfff;
       drawgfx(pf2_bitmap,Machine->gfx[2],tile,
			color, 0, 0, (16*mx)+256,16*my,
		 	0,TRANSPARENCY_NONE,0);
	}

    /* Rowscroll */
    if (pf2_attr[0]&0x4) {
    	int rscroll[256];

		scrolly=-((scroll2[2]<<8)+scroll2[3]);

		for (offs = 0;offs < 512;offs+=2)
			rscroll[offs/2] = -( (dec8_row[offs]<<8) + dec8_row[offs+1] ) -((scroll2[0]<<8)+scroll2[1]);

		copyscrollbitmap(bitmap,pf2_bitmap,256,rscroll,1,&scrolly,&Machine->drv->visible_area,TRANSPARENCY_NONE,0);
    } else {
		scrolly=-((scroll2[2]<<8)+scroll2[3]);
		scrollx=-((scroll2[0]<<8)+scroll2[1]);
		copyscrollbitmap(bitmap,pf2_bitmap,1,&scrollx,1,&scrolly,&Machine->drv->visible_area,TRANSPARENCY_NONE,0);
    }