/*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "emu.h" #include "includes/retofinv.h" PALETTE_INIT( retofinv ) { int i; /* allocate the colortable */ machine.colortable = colortable_alloc(machine, 0x100); /* create a lookup table for the palette */ for (i = 0; i < 0x100; i++) { int r = pal4bit(color_prom[i + 0x000]); int g = pal4bit(color_prom[i + 0x100]); int b = pal4bit(color_prom[i + 0x200]); colortable_palette_set_color(machine.colortable, i, MAKE_RGB(r, g, b)); } /* color_prom now points to the beginning of the lookup table */ color_prom += 0x300; /* fg chars (1bpp) */ for (i = 0; i < 0x200; i++) { UINT8 ctabentry; if (i & 0x01) ctabentry = i >> 1; else ctabentry = 0; colortable_entry_set_value(machine.colortable, i, ctabentry); } /* sprites and bg tiles */ for (i = 0; i < 0x800; i++) { UINT8 ctabentry = BITSWAP8(color_prom[i],4,5,6,7,3,2,1,0); colortable_entry_set_value(machine.colortable, i + 0x200, ctabentry); } } /*************************************************************************** Callbacks for the TileMap code ***************************************************************************/ /* convert from 32x32 to 36x28 */ static TILEMAP_MAPPER( tilemap_scan ) { row += 2; col -= 2; if (col & 0x20) return ((col & 0x1f) << 5) + row; else return (row << 5) + col; } static TILE_GET_INFO( bg_get_tile_info ) { retofinv_state *state = machine.driver_data(); SET_TILE_INFO( 2, state->m_bg_videoram[tile_index] + 256 * state->m_bg_bank, state->m_bg_videoram[0x400 + tile_index] & 0x3f, 0); } static TILE_GET_INFO( fg_get_tile_info ) { retofinv_state *state = machine.driver_data(); int color = state->m_fg_videoram[0x400 + tile_index]; tileinfo->group = color; SET_TILE_INFO( 0, state->m_fg_videoram[tile_index] + 256 * state->m_fg_bank, color, 0); } /*************************************************************************** Start the video hardware emulation. ***************************************************************************/ VIDEO_START( retofinv ) { retofinv_state *state = machine.driver_data(); state->m_bg_tilemap = tilemap_create(machine, bg_get_tile_info,tilemap_scan,8,8,36,28); state->m_fg_tilemap = tilemap_create(machine, fg_get_tile_info,tilemap_scan,8,8,36,28); colortable_configure_tilemap_groups(machine.colortable, state->m_fg_tilemap, machine.gfx[0], 0); } /*************************************************************************** Memory handlers ***************************************************************************/ WRITE8_HANDLER( retofinv_bg_videoram_w ) { retofinv_state *state = space->machine().driver_data(); state->m_bg_videoram[offset] = data; tilemap_mark_tile_dirty(state->m_bg_tilemap,offset & 0x3ff); } WRITE8_HANDLER( retofinv_fg_videoram_w ) { retofinv_state *state = space->machine().driver_data(); state->m_fg_videoram[offset] = data; tilemap_mark_tile_dirty(state->m_fg_tilemap,offset & 0x3ff); } WRITE8_HANDLER( retofinv_gfx_ctrl_w ) { retofinv_state *state = space->machine().driver_data(); switch (offset) { case 0: flip_screen_set(space->machine(), data & 1); break; case 1: if (state->m_fg_bank != (data & 1)) { state->m_fg_bank = data & 1; tilemap_mark_all_tiles_dirty(state->m_fg_tilemap); } break; case 2: if (state->m_bg_bank != (data & 1)) { state->m_bg_bank = data & 1; tilemap_mark_all_tiles_dirty(state->m_bg_tilemap); } break; } } /*************************************************************************** Display refresh ***************************************************************************/ static void draw_sprites(running_machine &machine, bitmap_t *bitmap) { retofinv_state *state = machine.driver_data(); UINT8 *spriteram = state->m_sharedram + 0x0780; UINT8 *spriteram_2 = state->m_sharedram + 0x0f80; UINT8 *spriteram_3 = state->m_sharedram + 0x1780; int offs; static const rectangle spritevisiblearea = { 2*8, 34*8-1, 0*8, 28*8-1 }; for (offs = 0;offs < 0x80;offs += 2) { static const int gfx_offs[2][2] = { { 0, 1 }, { 2, 3 } }; int sprite = spriteram[offs]; int color = spriteram[offs+1] & 0x3f; int sx = ((spriteram_2[offs+1] << 1) + ((spriteram_3[offs+1] & 0x80) >> 7)) - 39; int sy = 256 - ((spriteram_2[offs] << 1) + ((spriteram_3[offs] & 0x80) >> 7)) + 1; /* not sure about the flipping, it's hardly ever used (mostly for shots) */ int flipx = (spriteram_3[offs] & 0x01); int flipy = (spriteram_3[offs] & 0x02) >> 1; int sizey = (spriteram_3[offs] & 0x04) >> 2; int sizex = (spriteram_3[offs] & 0x08) >> 3; int x,y; sprite &= ~sizex; sprite &= ~(sizey << 1); if (flip_screen_get(machine)) { flipx ^= 1; flipy ^= 1; } sy -= 16 * sizey; sy = (sy & 0xff) - 32; // fix wraparound for (y = 0;y <= sizey;y++) { for (x = 0;x <= sizex;x++) { drawgfx_transmask(bitmap,&spritevisiblearea,machine.gfx[1], sprite + gfx_offs[y ^ (sizey * flipy)][x ^ (sizex * flipx)], color, flipx,flipy, sx + 16*x,sy + 16*y, colortable_get_transpen_mask(machine.colortable, machine.gfx[1], color, 0xff)); } } } } SCREEN_UPDATE( retofinv ) { retofinv_state *state = screen->machine().driver_data(); tilemap_draw(bitmap,cliprect,state->m_bg_tilemap,0,0); draw_sprites(screen->machine(), bitmap); tilemap_draw(bitmap,cliprect,state->m_fg_tilemap,0,0); return 0; }