/*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "driver.h" //UINT8 *sbasketb_scroll; UINT8 *sbasketb_palettebank; UINT8 *sbasketb_spriteram_select; static tilemap *bg_tilemap; /*************************************************************************** Convert the color PROMs into a more useable format. Super Basketball has three 256x4 palette PROMs (one per gun) and two 256x4 lookup table PROMs (one for characters, one for sprites). I don't know for sure how the palette PROMs are connected to the RGB output, but it's probably the usual: bit 3 -- 220 ohm resistor -- RED/GREEN/BLUE -- 470 ohm resistor -- RED/GREEN/BLUE -- 1 kohm resistor -- RED/GREEN/BLUE bit 0 -- 2.2kohm resistor -- RED/GREEN/BLUE ***************************************************************************/ PALETTE_INIT( sbasketb ) { int i; #define TOTAL_COLORS(gfxn) (machine->gfx[gfxn]->total_colors * machine->gfx[gfxn]->color_granularity) #define COLOR(gfxn,offs) (colortable[machine->drv->gfxdecodeinfo[gfxn].color_codes_start + offs]) for (i = 0;i < machine->drv->total_colors;i++) { int bit0,bit1,bit2,bit3,r,g,b; bit0 = (color_prom[0] >> 0) & 0x01; bit1 = (color_prom[0] >> 1) & 0x01; bit2 = (color_prom[0] >> 2) & 0x01; bit3 = (color_prom[0] >> 3) & 0x01; r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3; bit0 = (color_prom[machine->drv->total_colors] >> 0) & 0x01; bit1 = (color_prom[machine->drv->total_colors] >> 1) & 0x01; bit2 = (color_prom[machine->drv->total_colors] >> 2) & 0x01; bit3 = (color_prom[machine->drv->total_colors] >> 3) & 0x01; g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3; bit0 = (color_prom[2*machine->drv->total_colors] >> 0) & 0x01; bit1 = (color_prom[2*machine->drv->total_colors] >> 1) & 0x01; bit2 = (color_prom[2*machine->drv->total_colors] >> 2) & 0x01; bit3 = (color_prom[2*machine->drv->total_colors] >> 3) & 0x01; b = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3; palette_set_color(machine,i,MAKE_RGB(r,g,b)); color_prom++; } color_prom += 2*machine->drv->total_colors; /* color_prom now points to the beginning of the character lookup table */ /* characters use colors 240-255 */ for (i = 0;i < TOTAL_COLORS(0);i++) COLOR(0,i) = (*(color_prom++) & 0x0f) + 240; /* sprites use colors 0-256 (?) in 16 banks */ for (i = 0;i < TOTAL_COLORS(1)/16;i++) { int j; for (j = 0;j < 16;j++) COLOR(1,i + j * TOTAL_COLORS(1)/16) = (*color_prom & 0x0f) + 16 * j; color_prom++; } } WRITE8_HANDLER( sbasketb_videoram_w ) { videoram[offset] = data; tilemap_mark_tile_dirty(bg_tilemap, offset); } WRITE8_HANDLER( sbasketb_colorram_w ) { colorram[offset] = data; tilemap_mark_tile_dirty(bg_tilemap, offset); } WRITE8_HANDLER( sbasketb_flipscreen_w ) { if (flip_screen != data) { flip_screen_set(data); tilemap_mark_all_tiles_dirty(ALL_TILEMAPS); } } WRITE8_HANDLER( sbasketb_scroll_w ) { int col; for (col = 6; col < 32; col++) { tilemap_set_scrolly(bg_tilemap, col, data); } } static TILE_GET_INFO( get_bg_tile_info ) { int code = videoram[tile_index] + ((colorram[tile_index] & 0x20) << 3); int color = colorram[tile_index] & 0x0f; int flags = ((colorram[tile_index] & 0x40) ? TILE_FLIPX : 0) | ((colorram[tile_index] & 0x80) ? TILE_FLIPY : 0); SET_TILE_INFO(0, code, color, flags); } VIDEO_START( sbasketb ) { bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8, 8, 32, 32); tilemap_set_scroll_cols(bg_tilemap, 32); } static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) { int offs = (*sbasketb_spriteram_select & 0x01) * 0x100; int i; for (i = 0; i < 64; i++, offs += 4) { int sx = spriteram[offs + 2]; int sy = spriteram[offs + 3]; if (sx || sy) { int code = spriteram[offs + 0] | ((spriteram[offs + 1] & 0x20) << 3); int color = (spriteram[offs + 1] & 0x0f) + 16 * *sbasketb_palettebank; int flipx = spriteram[offs + 1] & 0x40; int flipy = spriteram[offs + 1] & 0x80; if (flip_screen) { sx = 240 - sx; sy = 240 - sy; flipx = !flipx; flipy = !flipy; } drawgfx(bitmap,machine->gfx[1], code, color, flipx, flipy, sx, sy, cliprect, TRANSPARENCY_PEN, 0); } } } VIDEO_UPDATE( sbasketb ) { tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0); draw_sprites(machine, bitmap, cliprect); return 0; }