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Diffstat (limited to 'src/mame/video/amspdwy.c')
-rw-r--r--src/mame/video/amspdwy.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/src/mame/video/amspdwy.c b/src/mame/video/amspdwy.c
new file mode 100644
index 00000000000..0ad15f89dc9
--- /dev/null
+++ b/src/mame/video/amspdwy.c
@@ -0,0 +1,150 @@
+/***************************************************************************
+
+ -= American Speedway =-
+
+ driver by Luca Elia (l.elia@tin.it)
+
+
+- 8x8 4 Color Tiles (with 8 palettes) used for both:
+
+ - 1 256x256 non scrolling layer
+ - 64 (32?) Sprites
+
+***************************************************************************/
+#include "driver.h"
+
+/* Variables only used here: */
+
+static tilemap *bg_tilemap;
+
+
+WRITE8_HANDLER( amspdwy_paletteram_w )
+{
+ data ^= 0xff;
+ paletteram_BBGGGRRR_w(offset,data);
+// paletteram_RRRGGGBB_w(offset,data);
+}
+
+WRITE8_HANDLER( amspdwy_flipscreen_w )
+{
+ static int flip = 0;
+ flip ^= 1;
+ flip_screen_set( flip );
+}
+
+/***************************************************************************
+
+ Callbacks for the TileMap code
+
+ [ Tiles Format ]
+
+ Videoram: 76543210 Code Low Bits
+ Colorram: 765-----
+ ---43--- Code High Bits
+ -----210 Color
+
+***************************************************************************/
+
+static TILE_GET_INFO( get_tile_info )
+{
+ UINT8 code = videoram[ tile_index ];
+ UINT8 color = colorram[ tile_index ];
+ SET_TILE_INFO(
+ 0,
+ code + ((color & 0x18)<<5),
+ color & 0x07,
+ 0);
+}
+
+WRITE8_HANDLER( amspdwy_videoram_w )
+{
+ videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( amspdwy_colorram_w )
+{
+ colorram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+
+/* logical (col,row) -> memory offset */
+static TILEMAP_MAPPER( tilemap_scan_cols_back )
+{
+ return col*num_rows + (num_rows - row - 1);
+}
+
+
+VIDEO_START( amspdwy )
+{
+ bg_tilemap = tilemap_create( get_tile_info, tilemap_scan_cols_back,
+ TILEMAP_TYPE_PEN, 8,8, 0x20, 0x20 );
+}
+
+
+
+/***************************************************************************
+
+ Sprites Drawing
+
+Offset: Format: Value:
+
+0 Y
+1 X
+2 Code Low Bits
+3 7------- Flip X
+ -6------ Flip Y
+ --5-----
+ ---4---- ?
+ ----3--- Code High Bit?
+ -----210 Color
+
+***************************************************************************/
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap,const rectangle *cliprect)
+{
+ int i;
+ int max_x = machine->screen[0].width - 1;
+ int max_y = machine->screen[0].height - 1;
+
+ for (i = 0; i < spriteram_size ; i += 4)
+ {
+ int y = spriteram[i+0];
+ int x = spriteram[i+1];
+ int code = spriteram[i+2];
+ int attr = spriteram[i+3];
+ int flipx = attr & 0x80;
+ int flipy = attr & 0x40;
+
+ if (flip_screen)
+ {
+ x = max_x - x - 8; y = max_y - y - 8;
+ flipx = !flipx; flipy = !flipy;
+ }
+
+ drawgfx(bitmap,machine->gfx[0],
+// code + ((attr & 0x18)<<5),
+ code + ((attr & 0x08)<<5),
+ attr,
+ flipx, flipy,
+ x,y,
+ cliprect,TRANSPARENCY_PEN,0 );
+ }
+}
+
+
+
+
+/***************************************************************************
+
+ Screen Drawing
+
+***************************************************************************/
+
+VIDEO_UPDATE( amspdwy )
+{
+ tilemap_draw(bitmap,cliprect,bg_tilemap,0,0);
+ draw_sprites(machine, bitmap,cliprect);
+ return 0;
+}