diff options
Diffstat (limited to 'src/mame/video/trackfld.c')
-rw-r--r-- | src/mame/video/trackfld.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/src/mame/video/trackfld.c b/src/mame/video/trackfld.c new file mode 100644 index 00000000000..6f04a03784a --- /dev/null +++ b/src/mame/video/trackfld.c @@ -0,0 +1,230 @@ +/*************************************************************************** + + video.c + + Functions to emulate the video hardware of the machine. + +***************************************************************************/ + +#include "driver.h" + +UINT8 *trackfld_scroll; +UINT8 *trackfld_scroll2; + +static tilemap *bg_tilemap; +static int bg_bank = 0, sprite_bank1 = 0, sprite_bank2 = 0; + +/*************************************************************************** + + Convert the color PROMs into a more useable format. + + Track 'n Field has one 32x8 palette PROM and two 256x4 lookup table PROMs + (one for characters, one for sprites). + The palette PROM is connected to the RGB output this way: + + bit 7 -- 220 ohm resistor -- BLUE + -- 470 ohm resistor -- BLUE + -- 220 ohm resistor -- GREEN + -- 470 ohm resistor -- GREEN + -- 1 kohm resistor -- GREEN + -- 220 ohm resistor -- RED + -- 470 ohm resistor -- RED + bit 0 -- 1 kohm resistor -- RED + +***************************************************************************/ +PALETTE_INIT( trackfld ) +{ + 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,r,g,b; + + + /* red component */ + bit0 = (*color_prom >> 0) & 0x01; + bit1 = (*color_prom >> 1) & 0x01; + bit2 = (*color_prom >> 2) & 0x01; + r = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + /* green component */ + bit0 = (*color_prom >> 3) & 0x01; + bit1 = (*color_prom >> 4) & 0x01; + bit2 = (*color_prom >> 5) & 0x01; + g = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + /* blue component */ + bit0 = 0; + bit1 = (*color_prom >> 6) & 0x01; + bit2 = (*color_prom >> 7) & 0x01; + b = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + + palette_set_color(machine,i,MAKE_RGB(r,g,b)); + + color_prom++; + } + + /* color_prom now points to the beginning of the lookup table */ + + + /* sprites */ + for (i = 0;i < TOTAL_COLORS(1);i++) + COLOR(1,i) = *(color_prom++) & 0x0f; + + /* characters */ + for (i = 0;i < TOTAL_COLORS(0);i++) + COLOR(0,i) = (*(color_prom++) & 0x0f) + 0x10; +} + +WRITE8_HANDLER( trackfld_videoram_w ) +{ + videoram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap, offset); +} + +WRITE8_HANDLER( trackfld_colorram_w ) +{ + colorram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap, offset); +} + +WRITE8_HANDLER( trackfld_flipscreen_w ) +{ + if (flip_screen != data) + { + flip_screen_set(data); + tilemap_mark_all_tiles_dirty(ALL_TILEMAPS); + } +} + +WRITE8_HANDLER( atlantol_gfxbank_w ) +{ + static int old = 0; + + if( data & 1 ) + { + /* male / female sprites switch */ + if( (old == 1 && (data & 1) == 1) || + (old == 0 && (data & 1) == 1) ) + sprite_bank2 = 0x200; + else + sprite_bank2 = 0; + + sprite_bank1 = 0; + + old = data & 1; + } + else + { + /* male / female sprites switch */ + if( (old == 0 && (data & 1) == 0) || + (old == 1 && (data & 1) == 0) ) + sprite_bank2 = 0; + else + sprite_bank2 = 0x200; + + sprite_bank1 = 0; + + old = data & 1; + } + + if( (data & 3) == 3 ) + { + if( sprite_bank2 ) + sprite_bank1 = 0x500; + else + sprite_bank1 = 0x300; + } + else if( (data & 3) == 2 ) + { + if( sprite_bank2 ) + sprite_bank1 = 0x300; + else + sprite_bank1 = 0x100; + } + + if( bg_bank != (data & 0x8) ) + { + bg_bank = data & 0x8; + tilemap_mark_all_tiles_dirty(bg_tilemap); + } +} + +static TILE_GET_INFO( get_bg_tile_info ) +{ + int attr = colorram[tile_index]; + int code = videoram[tile_index] + 4 * (attr & 0xc0); + int color = attr & 0x0f; + int flags = ((attr & 0x10) ? TILE_FLIPX : 0) | ((attr & 0x20) ? TILE_FLIPY : 0); + + if( bg_bank ) + code |= 0x400; + + SET_TILE_INFO(0, code, color, flags); +} + +VIDEO_START( trackfld ) +{ + bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows, + TILEMAP_TYPE_PEN, 8, 8, 64, 32); + + tilemap_set_scroll_rows(bg_tilemap, 32); +} + +static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) +{ + int offs; + + for (offs = spriteram_size - 2; offs >= 0; offs -= 2) + { + int attr = spriteram_2[offs]; + int code = spriteram[offs + 1]; + int color = attr & 0x0f; + int flipx = ~attr & 0x40; + int flipy = attr & 0x80; + int sx = spriteram[offs] - 1; + int sy = 240 - spriteram_2[offs + 1]; + + if (flip_screen) + { + sy = 240 - sy; + flipy = !flipy; + } + + /* Note that this adjustement must be done AFTER handling flip screen, thus */ + /* proving that this is a hardware related "feature" */ + sy += 1; + + drawgfx(bitmap, machine->gfx[1], + code + sprite_bank1 + sprite_bank2, color, + flipx, flipy, + sx, sy, + cliprect, + TRANSPARENCY_COLOR, 0); + + /* redraw with wraparound */ + drawgfx(bitmap,machine->gfx[1], + code + sprite_bank1 + sprite_bank2, color, + flipx, flipy, + sx - 256, sy, + cliprect, + TRANSPARENCY_COLOR, 0); + } +} + +VIDEO_UPDATE( trackfld ) +{ + int row, scrollx; + + for (row = 0; row < 32; row++) + { + scrollx = trackfld_scroll[row] + 256 * (trackfld_scroll2[row] & 0x01); + if (flip_screen) scrollx = -scrollx; + tilemap_set_scrollx(bg_tilemap, row, scrollx); + } + + tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0); + draw_sprites(machine, bitmap, cliprect); + return 0; +} |