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-rw-r--r--src/mame/video/wrally.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/src/mame/video/wrally.c b/src/mame/video/wrally.c
new file mode 100644
index 00000000000..9996176b709
--- /dev/null
+++ b/src/mame/video/wrally.c
@@ -0,0 +1,172 @@
+/***************************************************************************
+
+ World Rally Video Hardware
+
+ Functions to emulate the video hardware of the machine
+
+***************************************************************************/
+
+#include "driver.h"
+
+UINT16 *wrally_spriteram;
+UINT16 *wrally_vregs;
+UINT16 *wrally_videoram;
+
+static tilemap *pant[2];
+
+/* from machine/wrally.c */
+extern UINT16 *wrally_encr_table[2];
+
+/***************************************************************************
+
+ Callbacks for the TileMap code
+
+***************************************************************************/
+
+/*
+ Tile format
+ -----------
+
+ Screen 0 & 1: (64*32, 16x16 tiles)
+
+ Word | Bit(s) | Description
+ -----+-FEDCBA98-76543210-+--------------------------
+ 0 | --xxxxxx xxxxxxxx | code
+ 0 | xx------ -------- | not used?
+ 1 | xxxxxxxx xxxxxxxx | unknown
+
+ preliminary
+*/
+
+
+static TILE_GET_INFO( get_tile_info_wrally_screen0 )
+{
+ int data = wrally_videoram[tile_index << 1];
+ int data2 = wrally_videoram[(tile_index << 1) + 1];
+ int code = data & 0x3fff;
+
+ SET_TILE_INFO(0, code, data2 & 0x1f, TILE_FLIPXY((data2 >> 5) & 0x00));
+}
+
+static TILE_GET_INFO( get_tile_info_wrally_screen1 )
+{
+ int data = wrally_videoram[(0x2000/2) + (tile_index << 1)];
+ int data2 = wrally_videoram[(0x2000/2) + (tile_index << 1) + 1];
+ int code = data & 0x3fff;
+
+ SET_TILE_INFO(0, code, data2 & 0x1f, TILE_FLIPXY((data2 >> 5) & 0x00));
+}
+
+/***************************************************************************
+
+ Memory Handlers
+
+***************************************************************************/
+
+WRITE16_HANDLER( wrally_vram_w )
+{
+ wrally_videoram[offset] = wrally_encr_table[offset & 0x01][data];
+
+ tilemap_mark_tile_dirty(pant[(offset & 0x1fff) >> 12], ((offset << 1) & 0x1fff) >> 2);
+}
+
+
+/***************************************************************************
+
+ Start/Stop the video hardware emulation.
+
+***************************************************************************/
+
+VIDEO_START( wrally )
+{
+ pant[0] = tilemap_create(get_tile_info_wrally_screen0,tilemap_scan_rows,TILEMAP_TYPE_PEN,16,16,64,32);
+ pant[1] = tilemap_create(get_tile_info_wrally_screen1,tilemap_scan_rows,TILEMAP_TYPE_PEN,16,16,64,32);
+
+ tilemap_set_transparent_pen(pant[0],0);
+ tilemap_set_transparent_pen(pant[1],0);
+}
+
+
+/***************************************************************************
+
+ Sprites
+
+***************************************************************************/
+
+/*
+ Sprite Format
+ -------------
+
+ Word | Bit(s) | Description
+ -----+-FEDCBA98-76543210-+--------------------------
+ 0 | -------- xxxxxxxx | y position
+ 0 | --xxxxxx -------- | not used?
+ 0 | -x------ -------- | flipx
+ 0 | x------- -------- | flipy
+ 1 | xxxxxxxx xxxxxxxx | unknown
+ 2 | ------xx xxxxxxxx | x position
+ 2 | --xxxx-- -------- | sprite color (low 4 bits)
+ 2 | xx------ -------- | unknown
+ 3 | --xxxxxx xxxxxxxx | sprite code
+ 3 | xx------ -------- | not used?
+
+ preliminary
+*/
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int i, x, y, ex, ey;
+ const gfx_element *gfx = machine->gfx[0];
+
+ static int x_offset[2] = {0x0,0x2};
+ static int y_offset[2] = {0x0,0x1};
+
+ for (i = 3; i < (0x1000 - 6)/2; i += 4){
+ int sx = wrally_spriteram[i+2] & 0x03ff;
+ int sy = (240 - (wrally_spriteram[i] & 0x00ff)) & 0x00ff;
+ int number = wrally_spriteram[i+3] & 0x3fff;
+ int color = ((wrally_spriteram[i+2] & 0xfc00) >> 10);
+ int attr = (wrally_spriteram[i] & 0xfe00) >> 9;
+
+ int xflip = attr & 0x20;
+ int yflip = attr & 0x40;
+ int spr_size = 1;
+
+ color = (color & 0x0f);
+
+ for (y = 0; y < spr_size; y++){
+ for (x = 0; x < spr_size; x++){
+
+ ex = xflip ? (spr_size-1-x) : x;
+ ey = yflip ? (spr_size-1-y) : y;
+
+ drawgfx(bitmap,gfx,number + x_offset[ex] + y_offset[ey],
+ 0x20 + color,xflip,yflip,
+ sx-0x0f+x*16,sy+y*16,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+ }
+}
+
+/***************************************************************************
+
+ Display Refresh
+
+***************************************************************************/
+
+VIDEO_UPDATE( wrally )
+{
+ /* set scroll registers */
+ tilemap_set_scrolly(pant[0], 0, wrally_vregs[0]);
+ tilemap_set_scrollx(pant[0], 0, wrally_vregs[1]);
+ tilemap_set_scrolly(pant[1], 0, wrally_vregs[2]);
+ tilemap_set_scrollx(pant[1], 0, wrally_vregs[3]);
+
+ fillbitmap( bitmap, machine->pens[0], cliprect );
+
+ tilemap_draw(bitmap,cliprect,pant[1],0,0);
+ tilemap_draw(bitmap,cliprect,pant[0],0,0);
+ draw_sprites(machine, bitmap,cliprect);
+ return 0;
+}