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Diffstat (limited to 'src/mame/video/srumbler.c')
-rw-r--r--src/mame/video/srumbler.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/src/mame/video/srumbler.c b/src/mame/video/srumbler.c
new file mode 100644
index 00000000000..6720bc3f9fe
--- /dev/null
+++ b/src/mame/video/srumbler.c
@@ -0,0 +1,174 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+
+UINT8 *srumbler_backgroundram,*srumbler_foregroundram;
+static tilemap *bg_tilemap,*fg_tilemap;
+
+
+
+/***************************************************************************
+
+ Callbacks for the TileMap code
+
+***************************************************************************/
+
+static TILE_GET_INFO( get_fg_tile_info )
+{
+ UINT8 attr = srumbler_foregroundram[2*tile_index];
+ SET_TILE_INFO(
+ 0,
+ srumbler_foregroundram[2*tile_index + 1] + ((attr & 0x03) << 8),
+ (attr & 0x3c) >> 2,
+ (attr & 0x40) ? TILE_FORCE_LAYER0 : 0);
+}
+
+static TILE_GET_INFO( get_bg_tile_info )
+{
+ UINT8 attr = srumbler_backgroundram[2*tile_index];
+ SET_TILE_INFO(
+ 1,
+ srumbler_backgroundram[2*tile_index + 1] + ((attr & 0x07) << 8),
+ (attr & 0xe0) >> 5,
+ ((attr & 0x08) ? TILE_FLIPY : 0));
+ tileinfo->group = (attr & 0x10) >> 4;
+}
+
+
+
+/***************************************************************************
+
+ Start the video hardware emulation.
+
+***************************************************************************/
+
+VIDEO_START( srumbler )
+{
+ fg_tilemap = tilemap_create(get_fg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN,8,8,64,32);
+ bg_tilemap = tilemap_create(get_bg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN, 16,16,64,64);
+
+ tilemap_set_transparent_pen(fg_tilemap,3);
+
+ tilemap_set_transmask(bg_tilemap,0,0xffff,0x0000); /* split type 0 is totally transparent in front half */
+ tilemap_set_transmask(bg_tilemap,1,0x07ff,0xf800); /* split type 1 has pens 0-10 transparent in front half */
+}
+
+
+
+/***************************************************************************
+
+ Memory handlers
+
+***************************************************************************/
+
+WRITE8_HANDLER( srumbler_foreground_w )
+{
+ srumbler_foregroundram[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap,offset/2);
+}
+
+WRITE8_HANDLER( srumbler_background_w )
+{
+ srumbler_backgroundram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap,offset/2);
+}
+
+
+WRITE8_HANDLER( srumbler_4009_w )
+{
+ /* bit 0 flips screen */
+ flip_screen_set(data & 1);
+
+ /* bits 4-5 used during attract mode, unknown */
+
+ /* bits 6-7 coin counters */
+ coin_counter_w(0,data & 0x40);
+ coin_counter_w(1,data & 0x80);
+}
+
+
+WRITE8_HANDLER( srumbler_scroll_w )
+{
+ static int scroll[4];
+
+ scroll[offset] = data;
+
+ tilemap_set_scrollx(bg_tilemap,0,scroll[0] | (scroll[1] << 8));
+ tilemap_set_scrolly(bg_tilemap,0,scroll[2] | (scroll[3] << 8));
+}
+
+
+
+/***************************************************************************
+
+ Display refresh
+
+***************************************************************************/
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int offs;
+
+ /* Draw the sprites. */
+ for (offs = spriteram_size-4; offs>=0;offs -= 4)
+ {
+ /* SPRITES
+ =====
+ Attribute
+ 0x80 Code MSB
+ 0x40 Code MSB
+ 0x20 Code MSB
+ 0x10 Colour
+ 0x08 Colour
+ 0x04 Colour
+ 0x02 y Flip
+ 0x01 X MSB
+ */
+
+
+ int code,colour,sx,sy,flipy;
+ int attr = buffered_spriteram[offs+1];
+ code = buffered_spriteram[offs];
+ code += ( (attr&0xe0) << 3 );
+ colour = (attr & 0x1c)>>2;
+ sy = buffered_spriteram[offs + 2];
+ sx = buffered_spriteram[offs + 3] + 0x100 * ( attr & 0x01);
+ flipy = attr & 0x02;
+
+ if (flip_screen)
+ {
+ sx = 496 - sx;
+ sy = 240 - sy;
+ flipy = !flipy;
+ }
+
+ drawgfx(bitmap,machine->gfx[2],
+ code,
+ colour,
+ flip_screen,flipy,
+ sx, sy,
+ cliprect,TRANSPARENCY_PEN,15);
+ }
+}
+
+
+VIDEO_UPDATE( srumbler )
+{
+ tilemap_draw(bitmap,cliprect,bg_tilemap,TILEMAP_DRAW_LAYER1,0);
+ draw_sprites(machine, bitmap,cliprect);
+ tilemap_draw(bitmap,cliprect,bg_tilemap,TILEMAP_DRAW_LAYER0,0);
+ tilemap_draw(bitmap,cliprect,fg_tilemap,0,0);
+ return 0;
+}
+
+VIDEO_EOF( srumbler )
+{
+ buffer_spriteram_w(0,0);
+}