diff options
Diffstat (limited to 'src/mame/video/gundealr.c')
-rw-r--r-- | src/mame/video/gundealr.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/src/mame/video/gundealr.c b/src/mame/video/gundealr.c new file mode 100644 index 00000000000..40916d82f9b --- /dev/null +++ b/src/mame/video/gundealr.c @@ -0,0 +1,143 @@ +/*************************************************************************** + + video.c + + Functions to emulate the video hardware of the machine. + +***************************************************************************/ + +#include "driver.h" + + + +UINT8 *gundealr_bg_videoram,*gundealr_fg_videoram; + +static tilemap *bg_tilemap,*fg_tilemap; +static int flipscreen; + + + +/*************************************************************************** + + Callbacks for the TileMap code + +***************************************************************************/ + +static TILE_GET_INFO( get_bg_tile_info ) +{ + UINT8 attr = gundealr_bg_videoram[2*tile_index+1]; + SET_TILE_INFO( + 0, + gundealr_bg_videoram[2*tile_index] + ((attr & 0x07) << 8), + (attr & 0xf0) >> 4, + 0); +} + +static TILEMAP_MAPPER( gundealr_scan ) +{ + /* logical (col,row) -> memory offset */ + return (row & 0x0f) + ((col & 0x3f) << 4) + ((row & 0x10) << 6); +} + +static TILE_GET_INFO( get_fg_tile_info ) +{ + UINT8 attr = gundealr_fg_videoram[2*tile_index+1]; + SET_TILE_INFO( + 1, + gundealr_fg_videoram[2*tile_index] + ((attr & 0x03) << 8), + (attr & 0xf0) >> 4, + 0); +} + + + +/*************************************************************************** + + Start the video hardware emulation. + +***************************************************************************/ + +VIDEO_START( gundealr ) +{ + bg_tilemap = tilemap_create(get_bg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN, 8, 8,32,32); + fg_tilemap = tilemap_create(get_fg_tile_info,gundealr_scan, TILEMAP_TYPE_PEN,16,16,64,32); + + tilemap_set_transparent_pen(fg_tilemap,15); +} + + + +/*************************************************************************** + + Memory handlers + +***************************************************************************/ + +WRITE8_HANDLER( gundealr_bg_videoram_w ) +{ + gundealr_bg_videoram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap,offset/2); +} + +WRITE8_HANDLER( gundealr_fg_videoram_w ) +{ + gundealr_fg_videoram[offset] = data; + tilemap_mark_tile_dirty(fg_tilemap,offset/2); +} + +WRITE8_HANDLER( gundealr_paletteram_w ) +{ + int r,g,b,val; + + + paletteram[offset] = data; + + val = paletteram[offset & ~1]; + r = (val >> 4) & 0x0f; + g = (val >> 0) & 0x0f; + + val = paletteram[offset | 1]; + b = (val >> 4) & 0x0f; + /* TODO: the bottom 4 bits are used as well, but I'm not sure about the meaning */ + + palette_set_color_rgb(Machine,offset / 2,pal4bit(r),pal4bit(g),pal4bit(b)); +} + +WRITE8_HANDLER( gundealr_fg_scroll_w ) +{ + static UINT8 scroll[4]; + + scroll[offset] = data; + tilemap_set_scrollx(fg_tilemap,0,scroll[1] | ((scroll[0] & 0x03) << 8)); + tilemap_set_scrolly(fg_tilemap,0,scroll[3] | ((scroll[2] & 0x03) << 8)); +} + +WRITE8_HANDLER( yamyam_fg_scroll_w ) +{ + static UINT8 scroll[4]; + + scroll[offset] = data; + tilemap_set_scrollx(fg_tilemap,0,scroll[0] | ((scroll[1] & 0x03) << 8)); + tilemap_set_scrolly(fg_tilemap,0,scroll[2] | ((scroll[3] & 0x03) << 8)); +} + +WRITE8_HANDLER( gundealr_flipscreen_w ) +{ + flipscreen = data; + tilemap_set_flip(ALL_TILEMAPS,flipscreen ? (TILEMAP_FLIPY | TILEMAP_FLIPX) : 0); +} + + + +/*************************************************************************** + + Display refresh + +***************************************************************************/ + +VIDEO_UPDATE( gundealr ) +{ + tilemap_draw(bitmap,cliprect,bg_tilemap,0,0); + tilemap_draw(bitmap,cliprect,fg_tilemap,0,0); + return 0; +} |