diff options
Diffstat (limited to 'src/mame/video/wrally.c')
-rw-r--r-- | src/mame/video/wrally.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/src/mame/video/wrally.c b/src/mame/video/wrally.c new file mode 100644 index 00000000000..9996176b709 --- /dev/null +++ b/src/mame/video/wrally.c @@ -0,0 +1,172 @@ +/*************************************************************************** + + World Rally Video Hardware + + Functions to emulate the video hardware of the machine + +***************************************************************************/ + +#include "driver.h" + +UINT16 *wrally_spriteram; +UINT16 *wrally_vregs; +UINT16 *wrally_videoram; + +static tilemap *pant[2]; + +/* from machine/wrally.c */ +extern UINT16 *wrally_encr_table[2]; + +/*************************************************************************** + + Callbacks for the TileMap code + +***************************************************************************/ + +/* + Tile format + ----------- + + Screen 0 & 1: (64*32, 16x16 tiles) + + Word | Bit(s) | Description + -----+-FEDCBA98-76543210-+-------------------------- + 0 | --xxxxxx xxxxxxxx | code + 0 | xx------ -------- | not used? + 1 | xxxxxxxx xxxxxxxx | unknown + + preliminary +*/ + + +static TILE_GET_INFO( get_tile_info_wrally_screen0 ) +{ + int data = wrally_videoram[tile_index << 1]; + int data2 = wrally_videoram[(tile_index << 1) + 1]; + int code = data & 0x3fff; + + SET_TILE_INFO(0, code, data2 & 0x1f, TILE_FLIPXY((data2 >> 5) & 0x00)); +} + +static TILE_GET_INFO( get_tile_info_wrally_screen1 ) +{ + int data = wrally_videoram[(0x2000/2) + (tile_index << 1)]; + int data2 = wrally_videoram[(0x2000/2) + (tile_index << 1) + 1]; + int code = data & 0x3fff; + + SET_TILE_INFO(0, code, data2 & 0x1f, TILE_FLIPXY((data2 >> 5) & 0x00)); +} + +/*************************************************************************** + + Memory Handlers + +***************************************************************************/ + +WRITE16_HANDLER( wrally_vram_w ) +{ + wrally_videoram[offset] = wrally_encr_table[offset & 0x01][data]; + + tilemap_mark_tile_dirty(pant[(offset & 0x1fff) >> 12], ((offset << 1) & 0x1fff) >> 2); +} + + +/*************************************************************************** + + Start/Stop the video hardware emulation. + +***************************************************************************/ + +VIDEO_START( wrally ) +{ + pant[0] = tilemap_create(get_tile_info_wrally_screen0,tilemap_scan_rows,TILEMAP_TYPE_PEN,16,16,64,32); + pant[1] = tilemap_create(get_tile_info_wrally_screen1,tilemap_scan_rows,TILEMAP_TYPE_PEN,16,16,64,32); + + tilemap_set_transparent_pen(pant[0],0); + tilemap_set_transparent_pen(pant[1],0); +} + + +/*************************************************************************** + + Sprites + +***************************************************************************/ + +/* + Sprite Format + ------------- + + Word | Bit(s) | Description + -----+-FEDCBA98-76543210-+-------------------------- + 0 | -------- xxxxxxxx | y position + 0 | --xxxxxx -------- | not used? + 0 | -x------ -------- | flipx + 0 | x------- -------- | flipy + 1 | xxxxxxxx xxxxxxxx | unknown + 2 | ------xx xxxxxxxx | x position + 2 | --xxxx-- -------- | sprite color (low 4 bits) + 2 | xx------ -------- | unknown + 3 | --xxxxxx xxxxxxxx | sprite code + 3 | xx------ -------- | not used? + + preliminary +*/ + +static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) +{ + int i, x, y, ex, ey; + const gfx_element *gfx = machine->gfx[0]; + + static int x_offset[2] = {0x0,0x2}; + static int y_offset[2] = {0x0,0x1}; + + for (i = 3; i < (0x1000 - 6)/2; i += 4){ + int sx = wrally_spriteram[i+2] & 0x03ff; + int sy = (240 - (wrally_spriteram[i] & 0x00ff)) & 0x00ff; + int number = wrally_spriteram[i+3] & 0x3fff; + int color = ((wrally_spriteram[i+2] & 0xfc00) >> 10); + int attr = (wrally_spriteram[i] & 0xfe00) >> 9; + + int xflip = attr & 0x20; + int yflip = attr & 0x40; + int spr_size = 1; + + color = (color & 0x0f); + + for (y = 0; y < spr_size; y++){ + for (x = 0; x < spr_size; x++){ + + ex = xflip ? (spr_size-1-x) : x; + ey = yflip ? (spr_size-1-y) : y; + + drawgfx(bitmap,gfx,number + x_offset[ex] + y_offset[ey], + 0x20 + color,xflip,yflip, + sx-0x0f+x*16,sy+y*16, + cliprect,TRANSPARENCY_PEN,0); + } + } + } +} + +/*************************************************************************** + + Display Refresh + +***************************************************************************/ + +VIDEO_UPDATE( wrally ) +{ + /* set scroll registers */ + tilemap_set_scrolly(pant[0], 0, wrally_vregs[0]); + tilemap_set_scrollx(pant[0], 0, wrally_vregs[1]); + tilemap_set_scrolly(pant[1], 0, wrally_vregs[2]); + tilemap_set_scrollx(pant[1], 0, wrally_vregs[3]); + + fillbitmap( bitmap, machine->pens[0], cliprect ); + + tilemap_draw(bitmap,cliprect,pant[1],0,0); + tilemap_draw(bitmap,cliprect,pant[0],0,0); + draw_sprites(machine, bitmap,cliprect); + return 0; +} |