/*************************************************************************** Midway MCR-68k system ***************************************************************************/ #include "driver.h" #include "mcr.h" #define LOW_BYTE(x) ((x) & 0xff) UINT8 mcr68_sprite_clip; INT8 mcr68_sprite_xoffset; static tilemap *bg_tilemap; static tilemap *fg_tilemap; /************************************* * * Tilemap callbacks * *************************************/ static TILE_GET_INFO( get_bg_tile_info ) { int data = LOW_BYTE(videoram16[tile_index * 2]) | (LOW_BYTE(videoram16[tile_index * 2 + 1]) << 8); int code = (data & 0x3ff) | ((data >> 4) & 0xc00); int color = (~data >> 12) & 3; SET_TILE_INFO(0, code, color, TILE_FLIPYX((data >> 10) & 3)); if (machine->gfx[0]->total_elements < 0x1000) tileinfo->category = (data >> 15) & 1; } static TILE_GET_INFO( zwackery_get_bg_tile_info ) { int data = videoram16[tile_index]; int color = (data >> 13) & 7; SET_TILE_INFO(0, data & 0x3ff, color, TILE_FLIPYX((data >> 11) & 3)); } static TILE_GET_INFO( zwackery_get_fg_tile_info ) { int data = videoram16[tile_index]; int color = (data >> 13) & 7; SET_TILE_INFO(2, data & 0x3ff, color, TILE_FLIPYX((data >> 11) & 3)); tileinfo->category = (color != 0); } /************************************* * * Video startup * *************************************/ VIDEO_START( mcr68 ) { /* initialize the background tilemap */ bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 16,16, 32,32); tilemap_set_transparent_pen(bg_tilemap, 0); } VIDEO_START( zwackery ) { const UINT8 *colordatabase = (const UINT8 *)memory_region(REGION_GFX3); gfx_element *gfx0 = machine->gfx[0]; gfx_element *gfx2 = machine->gfx[2]; int code, y, x; /* initialize the background tilemap */ bg_tilemap = tilemap_create(zwackery_get_bg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 16,16, 32,32); /* initialize the foreground tilemap */ fg_tilemap = tilemap_create(zwackery_get_fg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 16,16, 32,32); tilemap_set_transparent_pen(fg_tilemap, 0); /* "colorize" each code */ for (code = 0; code < gfx0->total_elements; code++) { const UINT8 *coldata = colordatabase + code * 32; UINT8 *gfxdata0 = gfx0->gfxdata + code * gfx0->char_modulo; UINT8 *gfxdata2 = gfx2->gfxdata + code * gfx2->char_modulo; /* assume 16 rows */ for (y = 0; y < 16; y++) { UINT8 *gd0 = gfxdata0; UINT8 *gd2 = gfxdata2; /* 16 columns */ for (x = 0; x < 16; x++, gd0++, gd2++) { int coloffs = (y & 0x0c) | ((x >> 2) & 0x03); int pen0 = coldata[coloffs * 2 + 0]; int pen1 = coldata[coloffs * 2 + 1]; int tp0, tp1; /* every 4 pixels gets its own foreground/background colors */ *gd0 = *gd0 ? pen1 : pen0; /* for gfx 2, we convert all low-priority pens to 0 */ tp0 = (pen0 & 0x80) ? pen0 : 0; tp1 = (pen1 & 0x80) ? pen1 : 0; *gd2 = *gd2 ? tp1 : tp0; } /* advance */ gfxdata0 += gfx0->line_modulo; gfxdata2 += gfx2->line_modulo; } } } /************************************* * * Palette RAM writes * *************************************/ WRITE16_HANDLER( mcr68_paletteram_w ) { int newword; COMBINE_DATA(&paletteram16[offset]); newword = paletteram16[offset]; palette_set_color_rgb(Machine, offset, pal3bit(newword >> 6), pal3bit(newword >> 0), pal3bit(newword >> 3)); } WRITE16_HANDLER( zwackery_paletteram_w ) { int newword; COMBINE_DATA(&paletteram16[offset]); newword = paletteram16[offset]; palette_set_color_rgb(Machine, offset, pal5bit(~newword >> 10), pal5bit(~newword >> 0), pal5bit(~newword >> 5)); } /************************************* * * Video RAM writes * *************************************/ WRITE16_HANDLER( mcr68_videoram_w ) { COMBINE_DATA(&videoram16[offset]); tilemap_mark_tile_dirty(bg_tilemap, offset / 2); } WRITE16_HANDLER( zwackery_videoram_w ) { COMBINE_DATA(&videoram16[offset]); tilemap_mark_tile_dirty(bg_tilemap, offset); tilemap_mark_tile_dirty(fg_tilemap, offset); } WRITE16_HANDLER( zwackery_spriteram_w ) { /* yech -- Zwackery relies on the upper 8 bits of a spriteram read being $ff! */ /* to make this happen we always write $ff in the upper 8 bits */ COMBINE_DATA(&spriteram16[offset]); spriteram16[offset] |= 0xff00; } /************************************* * * Sprite update * *************************************/ static void mcr68_update_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect, int priority) { rectangle sprite_clip = machine->screen[0].visarea; int offs; /* adjust for clipping */ sprite_clip.min_x += mcr68_sprite_clip; sprite_clip.max_x -= mcr68_sprite_clip; sect_rect(&sprite_clip, cliprect); fillbitmap(priority_bitmap,1,&sprite_clip); /* loop over sprite RAM */ for (offs = spriteram_size / 2 - 4;offs >= 0;offs -= 4) { int code, color, flipx, flipy, x, y, flags; flags = LOW_BYTE(spriteram16[offs + 1]); code = LOW_BYTE(spriteram16[offs + 2]) + 256 * ((flags >> 3) & 0x01) + 512 * ((flags >> 6) & 0x03); /* skip if zero */ if (code == 0) continue; /* also skip if this isn't the priority we're drawing right now */ if (((flags >> 2) & 1) != priority) continue; /* extract the bits of information */ color = ~flags & 0x03; flipx = flags & 0x10; flipy = flags & 0x20; x = LOW_BYTE(spriteram16[offs + 3]) * 2 + mcr68_sprite_xoffset; y = (241 - LOW_BYTE(spriteram16[offs])) * 2; /* allow sprites to clip off the left side */ if (x > 0x1f0) x -= 0x200; /* sprites use color 0 for background pen and 8 for the 'under tile' pen. The color 8 is used to cover over other sprites. */ /* first draw the sprite, visible */ pdrawgfx(bitmap, machine->gfx[1], code, color, flipx, flipy, x, y, &sprite_clip, TRANSPARENCY_PENS, 0x0101, 0x00); /* then draw the mask, behind the background but obscuring following sprites */ pdrawgfx(bitmap, machine->gfx[1], code, color, flipx, flipy, x, y, &sprite_clip, TRANSPARENCY_PENS, 0xfeff, 0x02); } } static void zwackery_update_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect, int priority) { int offs; fillbitmap(priority_bitmap,1,cliprect); /* loop over sprite RAM */ for (offs = spriteram_size / 2 - 4;offs >= 0;offs -= 4) { int code, color, flipx, flipy, x, y, flags; /* get the code and skip if zero */ code = LOW_BYTE(spriteram16[offs + 2]); if (code == 0) continue; /* extract the flag bits and determine the color */ flags = LOW_BYTE(spriteram16[offs + 1]); color = ((~flags >> 2) & 0x0f) | ((flags & 0x02) << 3); /* for low priority, draw everything but color 7 */ if (!priority) { if (color == 7) continue; } /* for high priority, only draw color 7 */ else { if (color != 7) continue; } /* determine flipping and coordinates */ flipx = ~flags & 0x40; flipy = flags & 0x80; x = (231 - LOW_BYTE(spriteram16[offs + 3])) * 2; y = (241 - LOW_BYTE(spriteram16[offs])) * 2; if (x <= -32) x += 512; /* sprites use color 0 for background pen and 8 for the 'under tile' pen. The color 8 is used to cover over other sprites. */ /* first draw the sprite, visible */ pdrawgfx(bitmap, machine->gfx[1], code, color, flipx, flipy, x, y, cliprect, TRANSPARENCY_PENS, 0x0101, 0x00); /* then draw the mask, behind the background but obscuring following sprites */ pdrawgfx(bitmap, machine->gfx[1], code, color, flipx, flipy, x, y, cliprect, TRANSPARENCY_PENS, 0xfeff, 0x02); } } /************************************* * * General MCR/68k update * *************************************/ VIDEO_UPDATE( mcr68 ) { /* draw the background */ tilemap_draw(bitmap, cliprect, bg_tilemap, TILEMAP_DRAW_OPAQUE | 0, 0); tilemap_draw(bitmap, cliprect, bg_tilemap, TILEMAP_DRAW_OPAQUE | 1, 0); /* draw the low-priority sprites */ mcr68_update_sprites(machine, bitmap, cliprect, 0); /* redraw tiles with priority over sprites */ tilemap_draw(bitmap, cliprect, bg_tilemap, 1, 0); /* draw the high-priority sprites */ mcr68_update_sprites(machine, bitmap, cliprect, 1); return 0; } VIDEO_UPDATE( zwackery ) { /* draw the background */ tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0); /* draw the low-priority sprites */ zwackery_update_sprites(machine, bitmap, cliprect, 0); /* redraw tiles with priority over sprites */ tilemap_draw(bitmap, cliprect, fg_tilemap, 1, 0); /* draw the high-priority sprites */ zwackery_update_sprites(machine, bitmap, cliprect, 1); return 0; }