diff options
Diffstat (limited to 'src/mame/video/firetrap.c')
-rw-r--r-- | src/mame/video/firetrap.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/src/mame/video/firetrap.c b/src/mame/video/firetrap.c new file mode 100644 index 00000000000..47692280392 --- /dev/null +++ b/src/mame/video/firetrap.c @@ -0,0 +1,296 @@ +/*************************************************************************** + + video.c + + Functions to emulate the video hardware of the machine. + +***************************************************************************/ + +#include "driver.h" + + + +UINT8 *firetrap_bg1videoram; +UINT8 *firetrap_bg2videoram; +UINT8 *firetrap_fgvideoram; + +static tilemap *fg_tilemap, *bg1_tilemap, *bg2_tilemap; + + + +/*************************************************************************** + + Convert the color PROMs into a more useable format. + + Fire Trap has one 256x8 and one 256x4 palette PROMs. + I don't know for sure how the palette PROMs are connected to the RGB + output, but it's probably the usual: + + bit 7 -- 220 ohm resistor -- GREEN + -- 470 ohm resistor -- GREEN + -- 1 kohm resistor -- GREEN + -- 2.2kohm resistor -- GREEN + -- 220 ohm resistor -- RED + -- 470 ohm resistor -- RED + -- 1 kohm resistor -- RED + bit 0 -- 2.2kohm resistor -- RED + + bit 3 -- 220 ohm resistor -- BLUE + -- 470 ohm resistor -- BLUE + -- 1 kohm resistor -- BLUE + bit 0 -- 2.2kohm resistor -- BLUE + +***************************************************************************/ + +PALETTE_INIT( firetrap ) +{ + int i; + + + for (i = 0;i < machine->drv->total_colors;i++) + { + int bit0,bit1,bit2,bit3,r,g,b; + + + bit0 = (color_prom[i] >> 0) & 0x01; + bit1 = (color_prom[i] >> 1) & 0x01; + bit2 = (color_prom[i] >> 2) & 0x01; + bit3 = (color_prom[i] >> 3) & 0x01; + r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3; + bit0 = (color_prom[i] >> 4) & 0x01; + bit1 = (color_prom[i] >> 5) & 0x01; + bit2 = (color_prom[i] >> 6) & 0x01; + bit3 = (color_prom[i] >> 7) & 0x01; + g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3; + bit0 = (color_prom[i + machine->drv->total_colors] >> 0) & 0x01; + bit1 = (color_prom[i + machine->drv->total_colors] >> 1) & 0x01; + bit2 = (color_prom[i + machine->drv->total_colors] >> 2) & 0x01; + bit3 = (color_prom[i + 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)); + } +} + + +/*************************************************************************** + + Callbacks for the TileMap code + +***************************************************************************/ + +static TILEMAP_MAPPER( get_fg_memory_offset ) +{ + return (row ^ 0x1f) + (col << 5); +} + +static TILEMAP_MAPPER( get_bg_memory_offset ) +{ + return ((row & 0x0f) ^ 0x0f) | ((col & 0x0f) << 4) | + /* hole at bit 8 */ + ((row & 0x10) << 5) | ((col & 0x10) << 6); +} + +static TILE_GET_INFO( get_fg_tile_info ) +{ + int code, color; + + code = firetrap_fgvideoram[tile_index]; + color = firetrap_fgvideoram[tile_index + 0x400]; + SET_TILE_INFO( + 0, + code | ((color & 0x01) << 8), + color >> 4, + 0); +} + +INLINE void get_bg_tile_info(running_machine *machine, tile_data *tileinfo, int tile_index, UINT8 *bgvideoram, int gfx_region) +{ + int code, color; + + code = bgvideoram[tile_index]; + color = bgvideoram[tile_index + 0x100]; + SET_TILE_INFO( + gfx_region, + code + ((color & 0x03) << 8), + (color & 0x30) >> 4, + TILE_FLIPXY((color & 0x0c) >> 2)); +} + +static TILE_GET_INFO( get_bg1_tile_info ) +{ + get_bg_tile_info(machine, tileinfo, tile_index, firetrap_bg1videoram, 1); +} + +static TILE_GET_INFO( get_bg2_tile_info ) +{ + get_bg_tile_info(machine, tileinfo, tile_index, firetrap_bg2videoram, 2); +} + + +/*************************************************************************** + + Start the video hardware emulation. + +***************************************************************************/ + +VIDEO_START( firetrap ) +{ + fg_tilemap = tilemap_create(get_fg_tile_info, get_fg_memory_offset,TILEMAP_TYPE_PEN, 8, 8,32,32); + bg1_tilemap = tilemap_create(get_bg1_tile_info,get_bg_memory_offset,TILEMAP_TYPE_PEN,16,16,32,32); + bg2_tilemap = tilemap_create(get_bg2_tile_info,get_bg_memory_offset,TILEMAP_TYPE_PEN, 16,16,32,32); + + tilemap_set_transparent_pen(fg_tilemap,0); + tilemap_set_transparent_pen(bg1_tilemap,0); +} + + +/*************************************************************************** + + Memory handlers + +***************************************************************************/ + +WRITE8_HANDLER( firetrap_fgvideoram_w ) +{ + firetrap_fgvideoram[offset] = data; + tilemap_mark_tile_dirty(fg_tilemap,offset & 0x3ff); +} + +WRITE8_HANDLER( firetrap_bg1videoram_w ) +{ + firetrap_bg1videoram[offset] = data; + tilemap_mark_tile_dirty(bg1_tilemap,offset & 0x6ff); +} + +WRITE8_HANDLER( firetrap_bg2videoram_w ) +{ + firetrap_bg2videoram[offset] = data; + tilemap_mark_tile_dirty(bg2_tilemap,offset & 0x6ff); +} + + +WRITE8_HANDLER( firetrap_bg1_scrollx_w ) +{ + static UINT8 scroll[2]; + + scroll[offset] = data; + tilemap_set_scrollx(bg1_tilemap,0,scroll[0] | (scroll[1] << 8)); +} + +WRITE8_HANDLER( firetrap_bg1_scrolly_w ) +{ + static UINT8 scroll[2]; + + scroll[offset] = data; + tilemap_set_scrolly(bg1_tilemap,0,-(scroll[0] | (scroll[1] << 8))); +} + +WRITE8_HANDLER( firetrap_bg2_scrollx_w ) +{ + static UINT8 scroll[2]; + + scroll[offset] = data; + tilemap_set_scrollx(bg2_tilemap,0,scroll[0] | (scroll[1] << 8)); +} + +WRITE8_HANDLER( firetrap_bg2_scrolly_w ) +{ + static UINT8 scroll[2]; + + scroll[offset] = data; + tilemap_set_scrolly(bg2_tilemap,0,-(scroll[0] | (scroll[1] << 8))); +} + + +/*************************************************************************** + + Display refresh + +***************************************************************************/ + +static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) +{ + int offs; + + + for (offs = 0;offs < spriteram_size; offs += 4) + { + int sx,sy,flipx,flipy,code,color; + + + /* the meaning of bit 3 of [offs] is unknown */ + + sy = spriteram[offs]; + sx = spriteram[offs + 2]; + code = spriteram[offs + 3] + 4 * (spriteram[offs + 1] & 0xc0); + color = ((spriteram[offs + 1] & 0x08) >> 2) | (spriteram[offs + 1] & 0x01); + flipx = spriteram[offs + 1] & 0x04; + flipy = spriteram[offs + 1] & 0x02; + if (flip_screen) + { + sx = 240 - sx; + sy = 240 - sy; + flipx = !flipx; + flipy = !flipy; + } + + if (spriteram[offs + 1] & 0x10) /* double width */ + { + if (flip_screen) sy -= 16; + + drawgfx(bitmap,machine->gfx[3], + code & ~1, + color, + flipx,flipy, + sx,flipy ? sy : sy + 16, + cliprect,TRANSPARENCY_PEN,0); + drawgfx(bitmap,machine->gfx[3], + code | 1, + color, + flipx,flipy, + sx,flipy ? sy + 16 : sy, + cliprect,TRANSPARENCY_PEN,0); + + /* redraw with wraparound */ + drawgfx(bitmap,machine->gfx[3], + code & ~1, + color, + flipx,flipy, + sx - 256,flipy ? sy : sy + 16, + cliprect,TRANSPARENCY_PEN,0); + drawgfx(bitmap,machine->gfx[3], + code | 1, + color, + flipx,flipy, + sx - 256,flipy ? sy + 16 : sy, + cliprect,TRANSPARENCY_PEN,0); + } + else + { + drawgfx(bitmap,machine->gfx[3], + code, + color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + + /* redraw with wraparound */ + drawgfx(bitmap,machine->gfx[3], + code, + color, + flipx,flipy, + sx - 256,sy, + cliprect,TRANSPARENCY_PEN,0); + } + } +} + +VIDEO_UPDATE( firetrap ) +{ + tilemap_draw(bitmap,cliprect,bg2_tilemap,0,0); + tilemap_draw(bitmap,cliprect,bg1_tilemap,0,0); + draw_sprites(machine,bitmap,cliprect); + tilemap_draw(bitmap,cliprect,fg_tilemap,0,0); + return 0; +} |