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

Video Hardware for Irem Games:
Battle Road, Lode Runner, Kid Niki, Spelunker

Tile/sprite priority system (for the Kung Fu Master M62 board):
- Tiles with color code >= N (where N is set by jumpers) have priority over
  sprites. Only bits 1-4 of the color code are used, bit 0 is ignored.

- Two jumpers select whether bit 5 of the sprite color code should be used
  to index the high address pin of the color PROMs, or to select high
  priority over tiles (or both, but is this used by any game?)

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

#include "driver.h"

UINT8 *m62_tileram;
UINT8 *m62_textram;
UINT8 *horizon_scrollram;

static tilemap *m62_background;
static tilemap *m62_foreground;
static UINT8 flipscreen;
static const UINT8 *sprite_height_prom;
static INT32 m62_background_hscroll;
static INT32 m62_background_vscroll;

UINT8 *irem_textram;
size_t irem_textram_size;

static UINT8 kidniki_background_bank;
static INT32 kidniki_text_vscroll;

static INT32 spelunkr_palbank;

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

  Convert the color PROMs into a more useable format.

  Kung Fu Master has a six 256x4 palette PROMs (one per gun; three for
  characters, three for sprites).
  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 3 -- 220 ohm resistor  -- RED/GREEN/BLUE
        -- 470 ohm resistor  -- RED/GREEN/BLUE
        -- 1  kohm resistor  -- RED/GREEN/BLUE
  bit 0 -- 2.2kohm resistor  -- RED/GREEN/BLUE

***************************************************************************/
PALETTE_INIT( irem )
{
	int i;


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

		/* red component */
		bit0 = (color_prom[0] >> 0) & 0x01;
		bit1 = (color_prom[0] >> 1) & 0x01;
		bit2 = (color_prom[0] >> 2) & 0x01;
		bit3 = (color_prom[0] >> 3) & 0x01;
		r =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* green component */
		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;
		g =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* blue component */
		bit0 = (color_prom[2*machine->drv->total_colors] >> 0) & 0x01;
		bit1 = (color_prom[2*machine->drv->total_colors] >> 1) & 0x01;
		bit2 = (color_prom[2*machine->drv->total_colors] >> 2) & 0x01;
		bit3 = (color_prom[2*machine->drv->total_colors] >> 3) & 0x01;
		b =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		palette_set_color(machine,i,MAKE_RGB(r,g,b));

		color_prom++;
	}

	color_prom += 2*machine->drv->total_colors;
	/* color_prom now points to the beginning of the sprite height table */

	sprite_height_prom = color_prom;	/* we'll need this at run time */
}

PALETTE_INIT( battroad )
{
	int i;


	for (i = 0;i < 512;i++)
	{
		int bit0,bit1,bit2,bit3,r,g,b;

		/* red component */
		bit0 = (color_prom[0] >> 0) & 0x01;
		bit1 = (color_prom[0] >> 1) & 0x01;
		bit2 = (color_prom[0] >> 2) & 0x01;
		bit3 = (color_prom[0] >> 3) & 0x01;
		r =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* green component */
		bit0 = (color_prom[512] >> 0) & 0x01;
		bit1 = (color_prom[512] >> 1) & 0x01;
		bit2 = (color_prom[512] >> 2) & 0x01;
		bit3 = (color_prom[512] >> 3) & 0x01;
		g =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* blue component */
		bit0 = (color_prom[2*512] >> 0) & 0x01;
		bit1 = (color_prom[2*512] >> 1) & 0x01;
		bit2 = (color_prom[2*512] >> 2) & 0x01;
		bit3 = (color_prom[2*512] >> 3) & 0x01;
		b =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		palette_set_color(machine,i,MAKE_RGB(r,g,b));

		color_prom++;
	}

	color_prom += 2*512;
	/* color_prom now points to the beginning of the character color prom */

	for (i = 0;i < 32;i++)
	{
		int bit0,bit1,bit2,r,g,b;


		bit0 = (color_prom[i] >> 0) & 0x01;
		bit1 = (color_prom[i] >> 1) & 0x01;
		bit2 = (color_prom[i] >> 2) & 0x01;
		r = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2;
		bit0 = (color_prom[i] >> 3) & 0x01;
		bit1 = (color_prom[i] >> 4) & 0x01;
		bit2 = (color_prom[i] >> 5) & 0x01;
		g = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2;
		bit0 = 0;
		bit1 = (color_prom[i] >> 6) & 0x01;
		bit2 = (color_prom[i] >> 7) & 0x01;
		b = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2;

		palette_set_color(machine,i+512,MAKE_RGB(r,g,b));
	}

	color_prom += 32;
	/* color_prom now points to the beginning of the sprite height table */

	sprite_height_prom = color_prom;	/* we'll need this at run time */
}

PALETTE_INIT( spelunk2 )
{
	int i;


	/* chars */
	for (i = 0;i < 512;i++)
	{
		int bit0,bit1,bit2,bit3,r,g,b;

		/* red component */
		bit0 = (color_prom[0] >> 0) & 0x01;
		bit1 = (color_prom[0] >> 1) & 0x01;
		bit2 = (color_prom[0] >> 2) & 0x01;
		bit3 = (color_prom[0] >> 3) & 0x01;
		r =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* green component */
		bit0 = (color_prom[0] >> 4) & 0x01;
		bit1 = (color_prom[0] >> 5) & 0x01;
		bit2 = (color_prom[0] >> 6) & 0x01;
		bit3 = (color_prom[0] >> 7) & 0x01;
		g =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* blue component */
		bit0 = (color_prom[2*256] >> 0) & 0x01;
		bit1 = (color_prom[2*256] >> 1) & 0x01;
		bit2 = (color_prom[2*256] >> 2) & 0x01;
		bit3 = (color_prom[2*256] >> 3) & 0x01;
		b =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		palette_set_color(machine,i,MAKE_RGB(r,g,b));

		color_prom++;
	}

	color_prom += 2*256;

	/* sprites */
	for (i = 0;i < 256;i++)
	{
		int bit0,bit1,bit2,bit3,r,g,b;

		/* red component */
		bit0 = (color_prom[0] >> 0) & 0x01;
		bit1 = (color_prom[0] >> 1) & 0x01;
		bit2 = (color_prom[0] >> 2) & 0x01;
		bit3 = (color_prom[0] >> 3) & 0x01;
		r =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* green component */
		bit0 = (color_prom[256] >> 0) & 0x01;
		bit1 = (color_prom[256] >> 1) & 0x01;
		bit2 = (color_prom[256] >> 2) & 0x01;
		bit3 = (color_prom[256] >> 3) & 0x01;
		g =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
		/* blue component */
		bit0 = (color_prom[2*256] >> 0) & 0x01;
		bit1 = (color_prom[2*256] >> 1) & 0x01;
		bit2 = (color_prom[2*256] >> 2) & 0x01;
		bit3 = (color_prom[2*256] >> 3) & 0x01;
		b =  0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		palette_set_color(machine,i+512,MAKE_RGB(r,g,b));

		color_prom++;
	}

	color_prom += 2*256;


	/* color_prom now points to the beginning of the sprite height table */
	sprite_height_prom = color_prom;	/* we'll need this at run time */
}



static void register_savestate(void)
{
	state_save_register_global(flipscreen);
	state_save_register_global(kidniki_background_bank);
	state_save_register_global(m62_background_hscroll);
	state_save_register_global(m62_background_vscroll);
	state_save_register_global(kidniki_text_vscroll);
	state_save_register_global(spelunkr_palbank);
	state_save_register_global_pointer(irem_textram, irem_textram_size);
}

WRITE8_HANDLER( m62_flipscreen_w )
{
	/* screen flip is handled both by software and hardware */
	data ^= ~readinputport(4) & 1;

	flipscreen = data & 0x01;
	if (flipscreen)
		tilemap_set_flip(ALL_TILEMAPS, TILEMAP_FLIPX | TILEMAP_FLIPY);
	else
		tilemap_set_flip(ALL_TILEMAPS, 0);

	coin_counter_w(0,data & 2);
	coin_counter_w(1,data & 4);
}

WRITE8_HANDLER( m62_hscroll_low_w )
{
	m62_background_hscroll = ( m62_background_hscroll & 0xff00 ) | data;
}

WRITE8_HANDLER( m62_hscroll_high_w )
{
	m62_background_hscroll = ( m62_background_hscroll & 0xff ) | ( data << 8 );
}

WRITE8_HANDLER( m62_vscroll_low_w )
{
	m62_background_vscroll = ( m62_background_vscroll & 0xff00 ) | data;
}

WRITE8_HANDLER( m62_vscroll_high_w )
{
	m62_background_vscroll = ( m62_background_vscroll & 0xff ) | ( data << 8 );
}

WRITE8_HANDLER( m62_tileram_w )
{
	m62_tileram[ offset ] = data;
	tilemap_mark_tile_dirty( m62_background, offset >> 1 );
}

WRITE8_HANDLER( m62_textram_w )
{
	m62_textram[ offset ] = data;
	tilemap_mark_tile_dirty( m62_foreground, offset >> 1 );
}

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

  Draw the game screen in the given mame_bitmap.
  Do NOT call osd_update_display() from this function, it will be called by
  the main emulation engine.

***************************************************************************/
static void draw_sprites(mame_bitmap *bitmap, int colormask, int prioritymask, int priority)
{
	int offs;

	for (offs = 0;offs < spriteram_size;offs += 8)
	{
		int i,incr,code,col,flipx,flipy,sx,sy;

		if( ( spriteram[offs] & prioritymask ) == priority )
		{
			code = spriteram[offs+4] + ((spriteram[offs+5] & 0x07) << 8);
			col = spriteram[offs+0] & colormask;
			sx = 256 * (spriteram[offs+7] & 1) + spriteram[offs+6],
			sy = 256+128-15 - (256 * (spriteram[offs+3] & 1) + spriteram[offs+2]),
			flipx = spriteram[offs+5] & 0x40;
			flipy = spriteram[offs+5] & 0x80;

			i = sprite_height_prom[(code >> 5) & 0x1f];
			if (i == 1)	/* double height */
			{
				code &= ~1;
				sy -= 16;
			}
			else if (i == 2)	/* quadruple height */
			{
				i = 3;
				code &= ~3;
				sy -= 3*16;
			}

			if (flipscreen)
			{
				sx = 496 - sx;
				sy = 242 - i*16 - sy;	/* sprites are slightly misplaced by the hardware */
				flipx = !flipx;
				flipy = !flipy;
			}

			if (flipy)
			{
				incr = -1;
				code += i;
			}
			else incr = 1;

			do
			{
				drawgfx(bitmap,Machine->gfx[1],
						code + i * incr,col,
						flipx,flipy,
						sx,sy + 16 * i,
						&Machine->screen[0].visarea,TRANSPARENCY_PEN,0);

				i--;
			} while (i >= 0);
		}
	}
}

void m62_start( tile_get_info_fn tile_get_info, int rows, int cols, int x1, int y1, int x2, int y2 )
{
	m62_background = tilemap_create( tile_get_info, tilemap_scan_rows, TILEMAP_TRANSPARENT, x1, y1, x2, y2 );

	m62_background_hscroll = 0;
	m62_background_vscroll = 0;

	register_savestate();

	if( rows != 0 )
	{
		tilemap_set_scroll_rows( m62_background, rows );
	}
	if( cols != 0 )
	{
		tilemap_set_scroll_cols( m62_background, cols );
	}
}

void m62_textlayer( tile_get_info_fn tile_get_info, int rows, int cols, int x1, int y1, int x2, int y2 )
{
	m62_foreground = tilemap_create( tile_get_info, tilemap_scan_rows, TILEMAP_TRANSPARENT, x1, y1, x2, y2 );

	if( rows != 0 )
	{
		tilemap_set_scroll_rows( m62_foreground, rows );
	}
	if( cols != 0 )
	{
		tilemap_set_scroll_cols( m62_foreground, cols );
	}
}

WRITE8_HANDLER( kungfum_tileram_w )
{
	m62_tileram[ offset ] = data;
	tilemap_mark_tile_dirty( m62_background, offset & 0x7ff );
}

static TILE_GET_INFO( get_kungfum_bg_tile_info )
{
	int code;
	int color;
	int flags;
	code = m62_tileram[ tile_index ];
	color = m62_tileram[ tile_index + 0x800 ];
	flags = 0;
	if( ( color & 0x20 ) )
	{
		flags |= TILE_FLIPX;
	}
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, flags );

	/* is the following right? */
	if( ( tile_index / 64 ) < 6 || ( ( color & 0x1f ) >> 1 ) > 0x0c )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

VIDEO_UPDATE( kungfum )
{
	int i;
	for( i = 0; i < 6; i++ )
	{
		tilemap_set_scrollx( m62_background, i, 0 );
	}
	for( i = 6; i < 32; i++ )
	{
		tilemap_set_scrollx( m62_background, i, m62_background_hscroll );
	}
	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, 1, 0 );
	return 0;
}

VIDEO_START( kungfum )
{
	m62_start( get_kungfum_bg_tile_info, 32, 0, 8, 8, 64, 32 );
}


static TILE_GET_INFO( get_ldrun_bg_tile_info )
{
	int code;
	int color;
	int flags;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	flags = 0;
	if( ( color & 0x20 ) )
	{
		flags |= TILE_FLIPX;
	}
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, flags );
	if( ( ( color & 0x1f ) >> 1 ) >= 0x0c )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

VIDEO_UPDATE( ldrun )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );
	tilemap_set_scrolly( m62_background, 0, m62_background_vscroll );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x0f, 0x10, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, 1, 0 );
	draw_sprites( bitmap, 0x0f, 0x10, 0x10 );
	return 0;
}

VIDEO_START( ldrun )
{
	m62_start( get_ldrun_bg_tile_info, 1, 1, 8, 8, 64, 32 );
}

static TILE_GET_INFO( get_ldrun2_bg_tile_info )
{
	int code;
	int color;
	int flags;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	flags = 0;
	if( ( color & 0x20 ) )
	{
		flags |= TILE_FLIPX;
	}
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, flags );
	if( ( ( color & 0x1f ) >> 1 ) >= 0x04 )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

VIDEO_START( ldrun2 )
{
	m62_start( get_ldrun2_bg_tile_info, 1, 1, 8, 8, 64, 32 );
}

static TILE_GET_INFO( get_battroad_bg_tile_info )
{
	int code;
	int color;
	int flags;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	flags = 0;
	if( ( color & 0x20 ) )
	{
		flags |= TILE_FLIPX;
	}
	SET_TILE_INFO( 0, code | ( ( color & 0x40 ) << 3 ) | ( ( color & 0x10 ) << 4 ), color & 0x0f, flags );
	if( ( ( color & 0x1f ) >> 1 ) >= 0x04 )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

static TILE_GET_INFO( get_battroad_fg_tile_info )
{
	int code;
	int color;
	code = m62_textram[ tile_index << 1 ];
	color = m62_textram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 2, code | ( ( color & 0x40 ) << 3 ) | ( ( color & 0x10 ) << 4 ), color & 0x0f, 0 );
}

VIDEO_UPDATE( battroad )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );
	tilemap_set_scrolly( m62_background, 0, m62_background_vscroll );
	tilemap_set_scrollx( m62_foreground, 0, 128 );
	tilemap_set_scrolly( m62_foreground, 0, 0 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x0f, 0x10, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, 1, 0 );
	draw_sprites( bitmap, 0x0f, 0x10, 0x10 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	return 0;
}

VIDEO_START( battroad )
{
	m62_start( get_battroad_bg_tile_info, 1, 1, 8, 8, 64, 32 );
	m62_textlayer( get_battroad_fg_tile_info, 1, 1, 8, 8, 32, 32 );
}


/* almost identical but scrolling background, more characters, */
/* no char x flip, and more sprites */
static TILE_GET_INFO( get_ldrun4_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ) | ( ( color & 0x20 ) << 5 ), color & 0x1f, 0 );
}

VIDEO_UPDATE( ldrun4 )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	return 0;
}

VIDEO_START( ldrun4 )
{
	m62_start( get_ldrun4_bg_tile_info, 1, 0, 8, 8, 64, 32 );
}


static TILE_GET_INFO( get_lotlot_bg_tile_info )
{
	int code;
	int color;
	int flags;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	flags = 0;
	if( ( color & 0x20 ) )
	{
		flags |= TILE_FLIPX;
	}
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, flags );
}

static TILE_GET_INFO( get_lotlot_fg_tile_info )
{
	int code;
	int color;
	code = m62_textram[ tile_index << 1 ];
	color = m62_textram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 2, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, 0 );
}

VIDEO_UPDATE( lotlot )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll - 64 );
	tilemap_set_scrolly( m62_background, 0, m62_background_vscroll + 32 );
	tilemap_set_scrollx( m62_foreground, 0, -64 );
	tilemap_set_scrolly( m62_foreground, 0, 32 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	return 0;
}

VIDEO_START( lotlot )
{
	m62_start( get_lotlot_bg_tile_info, 1, 1, 12, 10, 32, 64 );
	m62_textlayer( get_lotlot_fg_tile_info, 1, 1, 12, 10, 32, 64 );
}


WRITE8_HANDLER( kidniki_text_vscroll_low_w )
{
	kidniki_text_vscroll = (kidniki_text_vscroll & 0xff00) | data;
}

WRITE8_HANDLER( kidniki_text_vscroll_high_w )
{
	kidniki_text_vscroll = (kidniki_text_vscroll & 0xff) | (data << 8);
}

WRITE8_HANDLER( kidniki_background_bank_w )
{
	if (kidniki_background_bank != (data & 1))
	{
		kidniki_background_bank = data & 1;
		tilemap_mark_all_tiles_dirty(m62_background);
	}
}

static TILE_GET_INFO( get_kidniki_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0xe0 ) << 3 ) | ( kidniki_background_bank << 11 ), color & 0x1f,
			TILE_SPLIT( ( ( color & 0xe0 ) == 0xe0 ) ? 1 : 0 ) );
}

static TILE_GET_INFO( get_kidniki_fg_tile_info )
{
	int code;
	int color;
	code = m62_textram[ tile_index << 1 ];
	color = m62_textram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 2, code | ( ( color & 0xc0 ) << 2 ), color & 0x1f, 0 );
}

VIDEO_UPDATE( kidniki )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );
	tilemap_set_scrollx( m62_foreground, 0, -64 );
	tilemap_set_scrolly( m62_foreground, 0, kidniki_text_vscroll + 128 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, TILEMAP_BACK, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, TILEMAP_FRONT, 0 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	return 0;
}

VIDEO_START( kidniki )
{
	m62_background = tilemap_create( get_kidniki_bg_tile_info, tilemap_scan_rows, TILEMAP_SPLIT, 8, 8, 64, 32 );

	m62_background_hscroll = 0;
	m62_background_vscroll = 0;

	tilemap_set_transmask(m62_background,0,0xffff,0x0000);	/* split type 0 is totally transparent in front half */
	tilemap_set_transmask(m62_background,1,0x0001,0xfffe);	/* split type 1 has pen 0 transparent in front half */

	register_savestate();

	m62_textlayer( get_kidniki_fg_tile_info, 1, 1, 12, 8, 32, 64 );
}


WRITE8_HANDLER( spelunkr_palbank_w )
{
	if (spelunkr_palbank != (data & 0x01))
	{
		spelunkr_palbank = data & 0x01;
		tilemap_mark_all_tiles_dirty(m62_background);
		tilemap_mark_all_tiles_dirty(m62_foreground);
	}
}

static TILE_GET_INFO( get_spelunkr_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0x10 ) << 4 ) | ( ( color & 0x20 ) << 6 ) | ( ( color & 0xc0 ) << 3 ), ( color & 0x0f ) | ( spelunkr_palbank << 4 ), 0 );
}

static TILE_GET_INFO( get_spelunkr_fg_tile_info )
{
	int code;
	int color;
	code = m62_textram[ tile_index << 1 ];
	color = m62_textram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 2, code | ( ( color & 0x10 ) << 4 ), ( color & 0x0f ) | ( spelunkr_palbank << 4 ), 0 );
}

VIDEO_UPDATE( spelunkr )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );
	tilemap_set_scrolly( m62_background, 0, m62_background_vscroll + 128 );
	tilemap_set_scrollx( m62_foreground, 0, -64 );
	tilemap_set_scrolly( m62_foreground, 0, 0 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	return 0;
}

VIDEO_START( spelunkr )
{
	m62_start( get_spelunkr_bg_tile_info, 1, 1, 8, 8, 64, 64 );
	m62_textlayer( get_spelunkr_fg_tile_info, 1, 1, 12, 8, 32, 32 );
}


WRITE8_HANDLER( spelunk2_gfxport_w )
{
	m62_hscroll_high_w(0,(data&2)>>1);
	m62_vscroll_high_w(0,(data&1));
	if (spelunkr_palbank != ((data & 0x0c) >> 2))
	{
		spelunkr_palbank = (data & 0x0c) >> 2;
		tilemap_mark_all_tiles_dirty(m62_background);
		tilemap_mark_all_tiles_dirty(m62_foreground);
	}
}

static TILE_GET_INFO( get_spelunk2_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0xf0 ) << 4 ), ( color & 0x0f ) | ( spelunkr_palbank << 4 ), 0 );
}

VIDEO_UPDATE( spelunk2 )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll - 1);
	tilemap_set_scrolly( m62_background, 0, m62_background_vscroll + 128 );
	tilemap_set_scrollx( m62_foreground, 0, -65 );
	tilemap_set_scrolly( m62_foreground, 0, 0 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	return 0;
}

VIDEO_START( spelunk2 )
{
	m62_start( get_spelunk2_bg_tile_info, 1, 1, 8, 8, 64, 64 );
	m62_textlayer( get_spelunkr_fg_tile_info, 1, 1, 12, 8, 32, 32 );
}


static TILE_GET_INFO( get_youjyudn_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0x60 ) << 3 ), color & 0x1f, 0 );
	if( ( ( color & 0x1f ) >> 1 ) >= 0x08 )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

static TILE_GET_INFO( get_youjyudn_fg_tile_info )
{
	int code;
	int color;
	code = m62_textram[ tile_index << 1 ];
	color = m62_textram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 2, code | ( ( color & 0xc0 ) << 2 ), ( color & 0x0f ), 0 );
}

VIDEO_UPDATE( youjyudn )
{
	tilemap_set_scrollx( m62_background, 0, m62_background_hscroll );
	tilemap_set_scrollx( m62_foreground, 0, -64 );
	tilemap_set_scrolly( m62_foreground, 0, 0 );
	tilemap_set_transparent_pen( m62_foreground, 0 );

	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, 1, 0 );
	tilemap_draw( bitmap, cliprect, m62_foreground, 0, 0 );
	return 0;
}

VIDEO_START( youjyudn )
{
	m62_start( get_youjyudn_bg_tile_info, 1, 0, 8, 16, 64, 16 );
	m62_textlayer( get_youjyudn_fg_tile_info, 1, 1, 12, 8, 32, 32 );
}


WRITE8_HANDLER( horizon_scrollram_w )
{
	horizon_scrollram[ offset ] = data;
}

static TILE_GET_INFO( get_horizon_bg_tile_info )
{
	int code;
	int color;
	code = m62_tileram[ tile_index << 1 ];
	color = m62_tileram[ ( tile_index << 1 ) | 1 ];
	SET_TILE_INFO( 0, code | ( ( color & 0xc0 ) << 2 ) | ( ( color & 0x20 ) << 5 ), color & 0x1f, 0 );
	if( ( ( color & 0x1f ) >> 1 ) >= 0x08 )
	{
		tileinfo->priority = 1;
	}
	else
	{
		tileinfo->priority = 0;
	}
}

VIDEO_UPDATE( horizon )
{
	int i;
	for( i = 0; i < 32; i++ )
	{
		tilemap_set_scrollx( m62_background, i, horizon_scrollram[ i << 1 ] | ( horizon_scrollram[ ( i << 1 ) | 1 ] << 8 ) );
	}
	tilemap_draw( bitmap, cliprect, m62_background, 0, 0 );
	draw_sprites( bitmap, 0x1f, 0x00, 0x00 );
	tilemap_draw( bitmap, cliprect, m62_background, 1, 0 );
	return 0;
}

VIDEO_START( horizon )
{
	m62_start( get_horizon_bg_tile_info, 32, 0, 8, 8, 64, 32 );
}
