#include "emu.h"
#include "includes/sderby.h"
/* BG Layer */
static TILE_GET_INFO( get_sderby_tile_info )
{
sderby_state *state = machine.driver_data<sderby_state>();
int tileno,colour;
tileno = state->m_videoram[tile_index*2];
colour = state->m_videoram[tile_index*2+1] & 0x0f;
SET_TILE_INFO(1,tileno,colour,0);
}
WRITE16_HANDLER( sderby_videoram_w )
{
sderby_state *state = space->machine().driver_data<sderby_state>();
COMBINE_DATA(&state->m_videoram[offset]);
tilemap_mark_tile_dirty(state->m_tilemap,offset/2);
}
/* MD Layer */
static TILE_GET_INFO( get_sderby_md_tile_info )
{
sderby_state *state = machine.driver_data<sderby_state>();
int tileno,colour;
tileno = state->m_md_videoram[tile_index*2];
colour = state->m_md_videoram[tile_index*2+1] & 0x0f;
SET_TILE_INFO(1,tileno,colour+16,0);
}
WRITE16_HANDLER( sderby_md_videoram_w )
{
sderby_state *state = space->machine().driver_data<sderby_state>();
COMBINE_DATA(&state->m_md_videoram[offset]);
tilemap_mark_tile_dirty(state->m_md_tilemap,offset/2);
}
/* FG Layer */
static TILE_GET_INFO( get_sderby_fg_tile_info )
{
sderby_state *state = machine.driver_data<sderby_state>();
int tileno,colour;
tileno = state->m_fg_videoram[tile_index*2];
colour = state->m_fg_videoram[tile_index*2+1] & 0x0f;
SET_TILE_INFO(0,tileno,colour+32,0);
}
WRITE16_HANDLER( sderby_fg_videoram_w )
{
sderby_state *state = space->machine().driver_data<sderby_state>();
COMBINE_DATA(&state->m_fg_videoram[offset]);
tilemap_mark_tile_dirty(state->m_fg_tilemap,offset/2);
}
static void draw_sprites(running_machine &machine, bitmap_t *bitmap,const rectangle *cliprect,int codeshift)
{
sderby_state *state = machine.driver_data<sderby_state>();
UINT16 *spriteram16 = state->m_spriteram;
int offs;
int height = machine.gfx[0]->height;
int colordiv = machine.gfx[0]->color_granularity / 16;
for (offs = 4;offs < state->m_spriteram_size/2;offs += 4)
{
int sx,sy,code,color,flipx;
sy = spriteram16[offs+3-4]; /* -4? what the... ??? */
if (sy == 0x2000) return; /* end of list marker */
flipx = sy & 0x4000;
sx = (spriteram16[offs+1] & 0x01ff) - 16-7;
sy = (256-8-height - sy) & 0xff;
code = spriteram16[offs+2] >> codeshift;
color = (spriteram16[offs+1] & 0x3e00) >> 9;
drawgfx_transpen(bitmap,cliprect,machine.gfx[1],
code,
color/colordiv+48,
flipx,0,
sx,sy,0);
}
}
VIDEO_START( sderby )
{
sderby_state *state = machine.driver_data<sderby_state>();
state->m_tilemap = tilemap_create(machine, get_sderby_tile_info,tilemap_scan_rows, 16, 16,32,32);
state->m_md_tilemap = tilemap_create(machine, get_sderby_md_tile_info,tilemap_scan_rows, 16, 16,32,32);
tilemap_set_transparent_pen(state->m_md_tilemap,0);
state->m_fg_tilemap = tilemap_create(machine, get_sderby_fg_tile_info,tilemap_scan_rows, 8, 8,64,32);
tilemap_set_transparent_pen(state->m_fg_tilemap,0);
}
SCREEN_UPDATE( sderby )
{
sderby_state *state = screen->machine().driver_data<sderby_state>();
tilemap_draw(bitmap,cliprect,state->m_tilemap,0,0);
draw_sprites(screen->machine(), bitmap,cliprect,0);
tilemap_draw(bitmap,cliprect,state->m_md_tilemap,0,0);
tilemap_draw(bitmap,cliprect,state->m_fg_tilemap,0,0);
return 0;
}
SCREEN_UPDATE( pmroulet )
{
sderby_state *state = screen->machine().driver_data<sderby_state>();
tilemap_draw(bitmap,cliprect,state->m_tilemap,0,0);
tilemap_draw(bitmap,cliprect,state->m_md_tilemap,0,0);
draw_sprites(screen->machine(), bitmap,cliprect,0);
tilemap_draw(bitmap,cliprect,state->m_fg_tilemap,0,0);
return 0;
}
WRITE16_HANDLER( sderby_scroll_w )
{
sderby_state *state = space->machine().driver_data<sderby_state>();
data = COMBINE_DATA(&state->m_scroll[offset]);
switch (offset)
{
case 0: tilemap_set_scrollx(state->m_fg_tilemap,0,data+2);break;
case 1: tilemap_set_scrolly(state->m_fg_tilemap,0,data-8);break;
case 2: tilemap_set_scrollx(state->m_md_tilemap,0,data+4);break;
case 3: tilemap_set_scrolly(state->m_md_tilemap,0,data-8);break;
case 4: tilemap_set_scrollx(state->m_tilemap,0,data+6); break;
case 5: tilemap_set_scrolly(state->m_tilemap,0,data-8); break;
}
}