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Diffstat (limited to 'src/mame/video/trackfld.c')
-rw-r--r--src/mame/video/trackfld.c230
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;
+}