/***************************************************************************
video.c
Functions to emulate the video hardware of the machine.
TODO:
- Get a dump of the PAL16L8 (IC38 - 4M). This controls transparency.
It takes as input 4 bits of sprite color, and 6 bits of background tile
color. It outputs a sprite enable line, a background enable line, and
a background select (which layer of background to draw).
- Add cocktail flipping.
***************************************************************************/
#include "driver.h"
static rectangle bottomvisiblearea =
{
16*8, 48*8-1,
6*8, 32*8-1
};
//UINT8 *vigilant_paletteram;
//UINT8 *vigilant_sprite_paletteram;
static int horiz_scroll_low=0;
static int horiz_scroll_high=0;
static int rear_horiz_scroll_low=0;
static int rear_horiz_scroll_high=0;
static int rear_color=0;
static int rear_disable=1;
static int rear_refresh=1;
static mame_bitmap *bg_bitmap;
VIDEO_START( vigilant )
{
video_start_generic(machine);
bg_bitmap = auto_bitmap_alloc(512*4,256,machine->screen[0].format);
}
/***************************************************************************
update_background
There are three background ROMs, each one contains a 512x256 picture.
Redraw them if the palette changes.
**************************************************************************/
static void update_background(running_machine *machine)
{
int row,col,page;
int charcode;
charcode=0;
/* There are only three background ROMs (4 on bunccaneers!) */
for (page=0; page<4; page++)
{
for( row=0; row<256; row++ )
{
for( col=0; col<512; col+=32 )
{
drawgfx(bg_bitmap,
machine->gfx[2],
charcode,
row < 128 ? 0 : 1,
0,0,
512*page + col,row,
0,TRANSPARENCY_NONE,0);
charcode++;
}
}
}
}
/***************************************************************************
vigilant_paletteram_w
There are two palette chips, each one is labelled "KNA91H014". One is
used for the sprites, one is used for the two background layers.
The chip has three enables (!CS, !E0, !E1), R/W pins, A0-A7 as input,
'L' and 'H' inputs, and D0-D4 as input. 'L' and 'H' are used to bank
into Red, Green, and Blue memory. There are only 5 bits of memory for
each byte, and a total of 256*3 bytes memory per chip.
There are additionally two sets of D0-D7 inputs per chip labelled 'A'
and 'B'. There is also an 'S' pin to select between the two input sets.
These are used to index a color triplet of RGB. The triplet is read
from RAM, and output to R0-R4, G0-G4, and B0-B4.
**************************************************************************/
WRITE8_HANDLER( vigilant_paletteram_w )
{
int bank,r,g,b;
paletteram[offset] = data;
bank = offset & 0x400;
offset &= 0xff;
r = (paletteram[bank + offset + 0x000] << 3) & 0xFF;
g = (paletteram[bank + offset + 0x100] << 3) & 0xFF;
b = (paletteram[bank + offset + 0x200] << 3) & 0xFF;
palette_set_color(Machine, (bank >> 2) + offset,MAKE_RGB(r,g,b));
}
/***************************************************************************
vigilant_horiz_scroll_w
horiz_scroll_low = HSPL, an 8-bit register
horiz_scroll_high = HSPH, a 1-bit register
**************************************************************************/
WRITE8_HANDLER( vigilant_horiz_scroll_w )
{
if (offset==0)
horiz_scroll_low = data;
else
horiz_scroll_high = (data & 0x01) * 256;
}
/***************************************************************************
vigilant_rear_horiz_scroll_w
rear_horiz_scroll_low = RHSPL, an 8-bit register
rear_horiz_scroll_high = RHSPH, an 8-bit register but only 3 bits are saved
***************************************************************************/
WRITE8_HANDLER( vigilant_rear_horiz_scroll_w )
{
if (offset==0)
rear_horiz_scroll_low = data;
else
rear_horiz_scroll_high = (data & 0x07) * 256;
}
/***************************************************************************
vigilant_rear_color_w
This is an 8-bit register labelled RCOD.
D6 is hooked to !ROME (rear_disable)
D3 = RCC2 (rear color bit 2)
D2 = RCC1 (rear color bit 1)
D0 = RCC0 (rear color bit 0)
I know it looks odd, but D1, D4, D5, and D7 are empty.
What makes this extremely odd is that RCC is supposed to hook up to the
palette. However, the top four bits of the palette inputs are labelled:
"RCC3", "RCC2", "V256E", "RCC0". Methinks there's a typo.
**************************************************************************/
WRITE8_HANDLER( vigilant_rear_color_w )
{
rear_disable = data & 0x40;
rear_color = (data & 0x0d);
}
/***************************************************************************
draw_foreground
???
**************************************************************************/
static void draw_foreground(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect, int priority, int opaque )
{
int offs;
int scroll = -(horiz_scroll_low + horiz_scroll_high);
for (offs = 0; offs<videoram_size; offs+=2 )
{
int sy = 8 * ((offs/2) / 64);
int sx = 8 * ((offs/2) % 64);
int attributes = videoram[offs+1];
int color = attributes & 0x0F;
int tile_number = videoram[offs] | ((attributes & 0xF0) << 4);
if (priority) /* foreground */
{
if ((color & 0x0c) == 0x0c) /* mask sprites */
{
if (sy >= 48)
{
sx = (sx + scroll) & 0x1ff;
drawgfx(bitmap,machine->gfx[0],
tile_number,
color,
0,0,
sx,sy,
&bottomvisiblearea,TRANSPARENCY_PENS,0x00ff);
}
}
}
else /* background */
{
if (sy >= 48)
sx = (sx + scroll) & 0x1ff;
drawgfx(bitmap,machine->gfx[0],
tile_number,
color,
0,0,
sx,sy,
cliprect,(opaque || color >= 4) ? TRANSPARENCY_NONE : TRANSPARENCY_PEN,0);
}
}
}
static void draw_background(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
{
int scrollx = 0x17a + 16*8 - (rear_horiz_scroll_low + rear_horiz_scroll_high);
if (rear_refresh)
{
update_background(machine);
rear_refresh=0;
}
copyscrollbitmap(bitmap,bg_bitmap,1,&scrollx,0,0,&bottomvisiblearea,TRANSPARENCY_NONE,0);
}
static void draw_sprites(running_machine *machine, mame_bitmap *bitmap,const rectangle *cliprect)
{
int offs;
for (offs = 0;offs < spriteram_size;offs += 8)
{
int code,color,sx,sy,flipx,flipy,h,y;
code = spriteram[offs+4] | ((spriteram[offs+5] & 0x0f) << 8);
color = spriteram[offs+0] & 0x0f;
sx = (spriteram[offs+6] | ((spriteram[offs+7] & 0x01) << 8));
sy = 256+128 - (spriteram[offs+2] | ((spriteram[offs+3] & 0x01) << 8));
flipx = spriteram[offs+5] & 0x40;
flipy = spriteram[offs+5] & 0x80;
h = 1 << ((spriteram[offs+5] & 0x30) >> 4);
sy -= 16 * h;
code &= ~(h - 1);
for (y = 0;y < h;y++)
{
int c = code;
if (flipy) c += h-1-y;
else c += y;
drawgfx(bitmap,machine->gfx[1],
c,
color,
flipx,flipy,
sx,sy + 16*y,
cliprect,TRANSPARENCY_PEN,0);
}
}
}
VIDEO_UPDATE( vigilant )
{
int i;
/* copy the background palette */
for (i = 0;i < 16;i++)
{
int r,g,b;
r = (paletteram[0x400 + 16 * rear_color + i] << 3) & 0xFF;
g = (paletteram[0x500 + 16 * rear_color + i] << 3) & 0xFF;
b = (paletteram[0x600 + 16 * rear_color + i] << 3) & 0xFF;
palette_set_color(machine,512 + i,MAKE_RGB(r,g,b));
r = (paletteram[0x400 + 16 * rear_color + 32 + i] << 3) & 0xFF;
g = (paletteram[0x500 + 16 * rear_color + 32 + i] << 3) & 0xFF;
b = (paletteram[0x600 + 16 * rear_color + 32 + i] << 3) & 0xFF;
palette_set_color(machine,512 + 16 + i,MAKE_RGB(r,g,b));
}
if (rear_disable) /* opaque foreground */
{
draw_foreground(machine,bitmap,cliprect,0,1);
draw_sprites(machine,bitmap,&bottomvisiblearea);
draw_foreground(machine,bitmap,cliprect,1,0);
}
else
{
draw_background(machine,bitmap,cliprect);
draw_foreground(machine,bitmap,cliprect,0,0);
draw_sprites(machine,bitmap,&bottomvisiblearea);
draw_foreground(machine,bitmap,cliprect,1,0); // priority tiles
}
return 0;
}
VIDEO_UPDATE( kikcubic )
{
int offs;
for (offs = 0; offs<videoram_size; offs+=2 )
{
int sy = 8 * ((offs/2) / 64);
int sx = 8 * ((offs/2) % 64);
int attributes = videoram[offs+1];
int color = (attributes & 0xF0) >> 4;
int tile_number = videoram[offs] | ((attributes & 0x0F) << 8);
if (dirtybuffer[offs] || dirtybuffer[offs+1])
{
dirtybuffer[offs] = dirtybuffer[offs+1] = 0;
drawgfx(tmpbitmap,machine->gfx[0],
tile_number,
color,
0,0,
sx,sy,
0,TRANSPARENCY_NONE,0);
}
}
copybitmap(bitmap,tmpbitmap,0,0,0,0,cliprect,TRANSPARENCY_NONE,0);
draw_sprites(machine,bitmap,cliprect);
return 0;
}