diff options
Diffstat (limited to 'src/mame/video/vastar.c')
-rw-r--r-- | src/mame/video/vastar.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/src/mame/video/vastar.c b/src/mame/video/vastar.c new file mode 100644 index 00000000000..dd6827b9a48 --- /dev/null +++ b/src/mame/video/vastar.c @@ -0,0 +1,229 @@ +/*************************************************************************** + + video.c + + Functions to emulate the video hardware of the machine. + +***************************************************************************/ + +#include "driver.h" + + + +UINT8 *vastar_bg1videoram,*vastar_bg2videoram,*vastar_fgvideoram; +UINT8 *vastar_bg1_scroll,*vastar_bg2_scroll; +UINT8 *vastar_sprite_priority; + +static tilemap *fg_tilemap, *bg1_tilemap, *bg2_tilemap; + + + +/*************************************************************************** + + Callbacks for the TileMap code + +***************************************************************************/ + +static TILE_GET_INFO( get_fg_tile_info ) +{ + int code, color; + + code = vastar_fgvideoram[tile_index + 0x800] | (vastar_fgvideoram[tile_index + 0x400] << 8); + color = vastar_fgvideoram[tile_index]; + SET_TILE_INFO( + 0, + code, + color & 0x3f, + 0); +} + +static TILE_GET_INFO( get_bg1_tile_info ) +{ + int code, color; + + code = vastar_bg1videoram[tile_index + 0x800] | (vastar_bg1videoram[tile_index] << 8); + color = vastar_bg1videoram[tile_index + 0xc00]; + SET_TILE_INFO( + 4, + code, + color & 0x3f, + 0); +} + +static TILE_GET_INFO( get_bg2_tile_info ) +{ + int code, color; + + code = vastar_bg2videoram[tile_index + 0x800] | (vastar_bg2videoram[tile_index] << 8); + color = vastar_bg2videoram[tile_index + 0xc00]; + SET_TILE_INFO( + 3, + code, + color & 0x3f, + 0); +} + + +/*************************************************************************** + + Start the video hardware emulation. + +***************************************************************************/ + +VIDEO_START( vastar ) +{ + fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32); + bg1_tilemap = tilemap_create(get_bg1_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32); + bg2_tilemap = tilemap_create(get_bg2_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32); + + tilemap_set_transparent_pen(fg_tilemap,0); + tilemap_set_transparent_pen(bg1_tilemap,0); + tilemap_set_transparent_pen(bg2_tilemap,0); + + tilemap_set_scroll_cols(bg1_tilemap, 32); + tilemap_set_scroll_cols(bg2_tilemap, 32); +} + + +/*************************************************************************** + + Memory handlers + +***************************************************************************/ + +WRITE8_HANDLER( vastar_fgvideoram_w ) +{ + vastar_fgvideoram[offset] = data; + tilemap_mark_tile_dirty(fg_tilemap,offset & 0x3ff); +} + +WRITE8_HANDLER( vastar_bg1videoram_w ) +{ + vastar_bg1videoram[offset] = data; + tilemap_mark_tile_dirty(bg1_tilemap,offset & 0x3ff); +} + +WRITE8_HANDLER( vastar_bg2videoram_w ) +{ + vastar_bg2videoram[offset] = data; + tilemap_mark_tile_dirty(bg2_tilemap,offset & 0x3ff); +} + + +READ8_HANDLER( vastar_bg1videoram_r ) +{ + return vastar_bg1videoram[offset]; +} + +READ8_HANDLER( vastar_bg2videoram_r ) +{ + return vastar_bg2videoram[offset]; +} + + +/*************************************************************************** + + Display refresh + +***************************************************************************/ + +static void draw_sprites(running_machine *machine, mame_bitmap *bitmap,const rectangle *cliprect) +{ + int offs; + + + for (offs = 0; offs < spriteram_size; offs += 2) + { + int code, sx, sy, color, flipx, flipy; + + + code = ((spriteram_3[offs] & 0xfc) >> 2) + ((spriteram_2[offs] & 0x01) << 6) + + ((offs & 0x20) << 2); + + sx = spriteram_3[offs + 1]; + sy = spriteram[offs]; + color = spriteram[offs + 1] & 0x3f; + flipx = spriteram_3[offs] & 0x02; + flipy = spriteram_3[offs] & 0x01; + + if (flip_screen) + { + flipx = !flipx; + flipy = !flipy; + } + + if (spriteram_2[offs] & 0x08) /* double width */ + { + if (!flip_screen) + sy = 224 - sy; + + drawgfx(bitmap,machine->gfx[2], + code/2, + color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + /* redraw with wraparound */ + drawgfx(bitmap,machine->gfx[2], + code/2, + color, + flipx,flipy, + sx,sy+256, + cliprect,TRANSPARENCY_PEN,0); + } + else + { + if (!flip_screen) + sy = 240 - sy; + + drawgfx(bitmap,machine->gfx[1], + code, + color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + } + } +} + +VIDEO_UPDATE( vastar ) +{ + int i; + + + for (i = 0;i < 32;i++) + { + tilemap_set_scrolly(bg1_tilemap,i,vastar_bg1_scroll[i]); + tilemap_set_scrolly(bg2_tilemap,i,vastar_bg2_scroll[i]); + } + + switch (*vastar_sprite_priority) + { + case 0: + tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0); + draw_sprites(machine, bitmap,cliprect); + tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0); + tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0); + break; + + case 2: + tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0); + draw_sprites(machine, bitmap,cliprect); + tilemap_draw(bitmap,cliprect, bg1_tilemap, 0,0); + tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0); + tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0); + break; + + case 3: + tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0); + tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0); + tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0); + draw_sprites(machine, bitmap,cliprect); + break; + + default: + logerror("Unimplemented priority %X\n", *vastar_sprite_priority); + break; + } + return 0; +} |