/*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "driver.h" UINT8 *srumbler_backgroundram,*srumbler_foregroundram; static tilemap *bg_tilemap,*fg_tilemap; /*************************************************************************** Callbacks for the TileMap code ***************************************************************************/ static TILE_GET_INFO( get_fg_tile_info ) { UINT8 attr = srumbler_foregroundram[2*tile_index]; SET_TILE_INFO( 0, srumbler_foregroundram[2*tile_index + 1] + ((attr & 0x03) << 8), (attr & 0x3c) >> 2, (attr & 0x40) ? TILE_FORCE_LAYER0 : 0); } static TILE_GET_INFO( get_bg_tile_info ) { UINT8 attr = srumbler_backgroundram[2*tile_index]; SET_TILE_INFO( 1, srumbler_backgroundram[2*tile_index + 1] + ((attr & 0x07) << 8), (attr & 0xe0) >> 5, ((attr & 0x08) ? TILE_FLIPY : 0)); tileinfo->group = (attr & 0x10) >> 4; } /*************************************************************************** Start the video hardware emulation. ***************************************************************************/ VIDEO_START( srumbler ) { fg_tilemap = tilemap_create(get_fg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN,8,8,64,32); bg_tilemap = tilemap_create(get_bg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN, 16,16,64,64); tilemap_set_transparent_pen(fg_tilemap,3); tilemap_set_transmask(bg_tilemap,0,0xffff,0x0000); /* split type 0 is totally transparent in front half */ tilemap_set_transmask(bg_tilemap,1,0x07ff,0xf800); /* split type 1 has pens 0-10 transparent in front half */ } /*************************************************************************** Memory handlers ***************************************************************************/ WRITE8_HANDLER( srumbler_foreground_w ) { srumbler_foregroundram[offset] = data; tilemap_mark_tile_dirty(fg_tilemap,offset/2); } WRITE8_HANDLER( srumbler_background_w ) { srumbler_backgroundram[offset] = data; tilemap_mark_tile_dirty(bg_tilemap,offset/2); } WRITE8_HANDLER( srumbler_4009_w ) { /* bit 0 flips screen */ flip_screen_set(data & 1); /* bits 4-5 used during attract mode, unknown */ /* bits 6-7 coin counters */ coin_counter_w(0,data & 0x40); coin_counter_w(1,data & 0x80); } WRITE8_HANDLER( srumbler_scroll_w ) { static int scroll[4]; scroll[offset] = data; tilemap_set_scrollx(bg_tilemap,0,scroll[0] | (scroll[1] << 8)); tilemap_set_scrolly(bg_tilemap,0,scroll[2] | (scroll[3] << 8)); } /*************************************************************************** Display refresh ***************************************************************************/ static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) { int offs; /* Draw the sprites. */ for (offs = spriteram_size-4; offs>=0;offs -= 4) { /* SPRITES ===== Attribute 0x80 Code MSB 0x40 Code MSB 0x20 Code MSB 0x10 Colour 0x08 Colour 0x04 Colour 0x02 y Flip 0x01 X MSB */ int code,colour,sx,sy,flipy; int attr = buffered_spriteram[offs+1]; code = buffered_spriteram[offs]; code += ( (attr&0xe0) << 3 ); colour = (attr & 0x1c)>>2; sy = buffered_spriteram[offs + 2]; sx = buffered_spriteram[offs + 3] + 0x100 * ( attr & 0x01); flipy = attr & 0x02; if (flip_screen) { sx = 496 - sx; sy = 240 - sy; flipy = !flipy; } drawgfx(bitmap,machine->gfx[2], code, colour, flip_screen,flipy, sx, sy, cliprect,TRANSPARENCY_PEN,15); } } VIDEO_UPDATE( srumbler ) { tilemap_draw(bitmap,cliprect,bg_tilemap,TILEMAP_DRAW_LAYER1,0); draw_sprites(machine, bitmap,cliprect); tilemap_draw(bitmap,cliprect,bg_tilemap,TILEMAP_DRAW_LAYER0,0); tilemap_draw(bitmap,cliprect,fg_tilemap,0,0); return 0; } VIDEO_EOF( srumbler ) { buffer_spriteram_w(0,0); }