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-rw-r--r--src/mame/video/vastar.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/src/mame/video/vastar.c b/src/mame/video/vastar.c
new file mode 100644
index 00000000000..dd6827b9a48
--- /dev/null
+++ b/src/mame/video/vastar.c
@@ -0,0 +1,229 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+
+
+UINT8 *vastar_bg1videoram,*vastar_bg2videoram,*vastar_fgvideoram;
+UINT8 *vastar_bg1_scroll,*vastar_bg2_scroll;
+UINT8 *vastar_sprite_priority;
+
+static tilemap *fg_tilemap, *bg1_tilemap, *bg2_tilemap;
+
+
+
+/***************************************************************************
+
+ Callbacks for the TileMap code
+
+***************************************************************************/
+
+static TILE_GET_INFO( get_fg_tile_info )
+{
+ int code, color;
+
+ code = vastar_fgvideoram[tile_index + 0x800] | (vastar_fgvideoram[tile_index + 0x400] << 8);
+ color = vastar_fgvideoram[tile_index];
+ SET_TILE_INFO(
+ 0,
+ code,
+ color & 0x3f,
+ 0);
+}
+
+static TILE_GET_INFO( get_bg1_tile_info )
+{
+ int code, color;
+
+ code = vastar_bg1videoram[tile_index + 0x800] | (vastar_bg1videoram[tile_index] << 8);
+ color = vastar_bg1videoram[tile_index + 0xc00];
+ SET_TILE_INFO(
+ 4,
+ code,
+ color & 0x3f,
+ 0);
+}
+
+static TILE_GET_INFO( get_bg2_tile_info )
+{
+ int code, color;
+
+ code = vastar_bg2videoram[tile_index + 0x800] | (vastar_bg2videoram[tile_index] << 8);
+ color = vastar_bg2videoram[tile_index + 0xc00];
+ SET_TILE_INFO(
+ 3,
+ code,
+ color & 0x3f,
+ 0);
+}
+
+
+/***************************************************************************
+
+ Start the video hardware emulation.
+
+***************************************************************************/
+
+VIDEO_START( vastar )
+{
+ fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32);
+ bg1_tilemap = tilemap_create(get_bg1_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32);
+ bg2_tilemap = tilemap_create(get_bg2_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32);
+
+ tilemap_set_transparent_pen(fg_tilemap,0);
+ tilemap_set_transparent_pen(bg1_tilemap,0);
+ tilemap_set_transparent_pen(bg2_tilemap,0);
+
+ tilemap_set_scroll_cols(bg1_tilemap, 32);
+ tilemap_set_scroll_cols(bg2_tilemap, 32);
+}
+
+
+/***************************************************************************
+
+ Memory handlers
+
+***************************************************************************/
+
+WRITE8_HANDLER( vastar_fgvideoram_w )
+{
+ vastar_fgvideoram[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap,offset & 0x3ff);
+}
+
+WRITE8_HANDLER( vastar_bg1videoram_w )
+{
+ vastar_bg1videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg1_tilemap,offset & 0x3ff);
+}
+
+WRITE8_HANDLER( vastar_bg2videoram_w )
+{
+ vastar_bg2videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg2_tilemap,offset & 0x3ff);
+}
+
+
+READ8_HANDLER( vastar_bg1videoram_r )
+{
+ return vastar_bg1videoram[offset];
+}
+
+READ8_HANDLER( vastar_bg2videoram_r )
+{
+ return vastar_bg2videoram[offset];
+}
+
+
+/***************************************************************************
+
+ Display refresh
+
+***************************************************************************/
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap,const rectangle *cliprect)
+{
+ int offs;
+
+
+ for (offs = 0; offs < spriteram_size; offs += 2)
+ {
+ int code, sx, sy, color, flipx, flipy;
+
+
+ code = ((spriteram_3[offs] & 0xfc) >> 2) + ((spriteram_2[offs] & 0x01) << 6)
+ + ((offs & 0x20) << 2);
+
+ sx = spriteram_3[offs + 1];
+ sy = spriteram[offs];
+ color = spriteram[offs + 1] & 0x3f;
+ flipx = spriteram_3[offs] & 0x02;
+ flipy = spriteram_3[offs] & 0x01;
+
+ if (flip_screen)
+ {
+ flipx = !flipx;
+ flipy = !flipy;
+ }
+
+ if (spriteram_2[offs] & 0x08) /* double width */
+ {
+ if (!flip_screen)
+ sy = 224 - sy;
+
+ drawgfx(bitmap,machine->gfx[2],
+ code/2,
+ color,
+ flipx,flipy,
+ sx,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ /* redraw with wraparound */
+ drawgfx(bitmap,machine->gfx[2],
+ code/2,
+ color,
+ flipx,flipy,
+ sx,sy+256,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ else
+ {
+ if (!flip_screen)
+ sy = 240 - sy;
+
+ drawgfx(bitmap,machine->gfx[1],
+ code,
+ color,
+ flipx,flipy,
+ sx,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+}
+
+VIDEO_UPDATE( vastar )
+{
+ int i;
+
+
+ for (i = 0;i < 32;i++)
+ {
+ tilemap_set_scrolly(bg1_tilemap,i,vastar_bg1_scroll[i]);
+ tilemap_set_scrolly(bg2_tilemap,i,vastar_bg2_scroll[i]);
+ }
+
+ switch (*vastar_sprite_priority)
+ {
+ case 0:
+ tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0);
+ draw_sprites(machine, bitmap,cliprect);
+ tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0);
+ tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0);
+ break;
+
+ case 2:
+ tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0);
+ draw_sprites(machine, bitmap,cliprect);
+ tilemap_draw(bitmap,cliprect, bg1_tilemap, 0,0);
+ tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0);
+ tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0);
+ break;
+
+ case 3:
+ tilemap_draw(bitmap,cliprect, bg1_tilemap, TILEMAP_DRAW_OPAQUE,0);
+ tilemap_draw(bitmap,cliprect, bg2_tilemap, 0,0);
+ tilemap_draw(bitmap,cliprect, fg_tilemap, 0,0);
+ draw_sprites(machine, bitmap,cliprect);
+ break;
+
+ default:
+ logerror("Unimplemented priority %X\n", *vastar_sprite_priority);
+ break;
+ }
+ return 0;
+}