/*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "emu.h" #include "includes/gundealr.h" /*************************************************************************** Callbacks for the TileMap code ***************************************************************************/ static TILE_GET_INFO( get_bg_tile_info ) { gundealr_state *state = machine.driver_data(); UINT8 attr = state->m_bg_videoram[2 * tile_index + 1]; SET_TILE_INFO( 0, state->m_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 ) { gundealr_state *state = machine.driver_data(); UINT8 attr = state->m_fg_videoram[2 * tile_index + 1]; SET_TILE_INFO( 1, state->m_fg_videoram[2 * tile_index] + ((attr & 0x03) << 8), (attr & 0xf0) >> 4, 0); } /*************************************************************************** Start the video hardware emulation. ***************************************************************************/ VIDEO_START( gundealr ) { gundealr_state *state = machine.driver_data(); state->m_bg_tilemap = tilemap_create(machine, get_bg_tile_info, tilemap_scan_cols, 8, 8, 32, 32); state->m_fg_tilemap = tilemap_create(machine, get_fg_tile_info, gundealr_scan, 16, 16, 64, 32); tilemap_set_transparent_pen(state->m_fg_tilemap, 15); } /*************************************************************************** Memory handlers ***************************************************************************/ WRITE8_HANDLER( gundealr_bg_videoram_w ) { gundealr_state *state = space->machine().driver_data(); state->m_bg_videoram[offset] = data; tilemap_mark_tile_dirty(state->m_bg_tilemap, offset / 2); } WRITE8_HANDLER( gundealr_fg_videoram_w ) { gundealr_state *state = space->machine().driver_data(); state->m_fg_videoram[offset] = data; tilemap_mark_tile_dirty(state->m_fg_tilemap, offset / 2); } WRITE8_HANDLER( gundealr_paletteram_w ) { gundealr_state *state = space->machine().driver_data(); int r,g,b,val; state->m_paletteram[offset] = data; val = state->m_paletteram[offset & ~1]; r = (val >> 4) & 0x0f; g = (val >> 0) & 0x0f; val = state->m_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(space->machine(), offset / 2, pal4bit(r), pal4bit(g), pal4bit(b)); } WRITE8_HANDLER( gundealr_fg_scroll_w ) { gundealr_state *state = space->machine().driver_data(); state->m_scroll[offset] = data; tilemap_set_scrollx(state->m_fg_tilemap, 0, state->m_scroll[1] | ((state->m_scroll[0] & 0x03) << 8)); tilemap_set_scrolly(state->m_fg_tilemap, 0, state->m_scroll[3] | ((state->m_scroll[2] & 0x03) << 8)); } WRITE8_HANDLER( yamyam_fg_scroll_w ) { gundealr_state *state = space->machine().driver_data(); state->m_scroll[offset] = data; tilemap_set_scrollx(state->m_fg_tilemap, 0, state->m_scroll[0] | ((state->m_scroll[1] & 0x03) << 8)); tilemap_set_scrolly(state->m_fg_tilemap, 0, state->m_scroll[2] | ((state->m_scroll[3] & 0x03) << 8)); } WRITE8_HANDLER( gundealr_flipscreen_w ) { gundealr_state *state = space->machine().driver_data(); state->m_flipscreen = data; tilemap_set_flip_all(space->machine(), state->m_flipscreen ? (TILEMAP_FLIPY | TILEMAP_FLIPX) : 0); } /*************************************************************************** Display refresh ***************************************************************************/ SCREEN_UPDATE( gundealr ) { gundealr_state *state = screen->machine().driver_data(); tilemap_draw(bitmap, cliprect, state->m_bg_tilemap, 0, 0); tilemap_draw(bitmap, cliprect, state->m_fg_tilemap, 0, 0); return 0; }