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-rw-r--r--src/mame/video/firetrap.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/src/mame/video/firetrap.c b/src/mame/video/firetrap.c
new file mode 100644
index 00000000000..47692280392
--- /dev/null
+++ b/src/mame/video/firetrap.c
@@ -0,0 +1,296 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+
+
+UINT8 *firetrap_bg1videoram;
+UINT8 *firetrap_bg2videoram;
+UINT8 *firetrap_fgvideoram;
+
+static tilemap *fg_tilemap, *bg1_tilemap, *bg2_tilemap;
+
+
+
+/***************************************************************************
+
+ Convert the color PROMs into a more useable format.
+
+ Fire Trap has one 256x8 and one 256x4 palette PROMs.
+ I don't know for sure how the palette PROMs are connected to the RGB
+ output, but it's probably the usual:
+
+ bit 7 -- 220 ohm resistor -- GREEN
+ -- 470 ohm resistor -- GREEN
+ -- 1 kohm resistor -- GREEN
+ -- 2.2kohm resistor -- GREEN
+ -- 220 ohm resistor -- RED
+ -- 470 ohm resistor -- RED
+ -- 1 kohm resistor -- RED
+ bit 0 -- 2.2kohm resistor -- RED
+
+ bit 3 -- 220 ohm resistor -- BLUE
+ -- 470 ohm resistor -- BLUE
+ -- 1 kohm resistor -- BLUE
+ bit 0 -- 2.2kohm resistor -- BLUE
+
+***************************************************************************/
+
+PALETTE_INIT( firetrap )
+{
+ int i;
+
+
+ for (i = 0;i < machine->drv->total_colors;i++)
+ {
+ int bit0,bit1,bit2,bit3,r,g,b;
+
+
+ bit0 = (color_prom[i] >> 0) & 0x01;
+ bit1 = (color_prom[i] >> 1) & 0x01;
+ bit2 = (color_prom[i] >> 2) & 0x01;
+ bit3 = (color_prom[i] >> 3) & 0x01;
+ r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+ bit0 = (color_prom[i] >> 4) & 0x01;
+ bit1 = (color_prom[i] >> 5) & 0x01;
+ bit2 = (color_prom[i] >> 6) & 0x01;
+ bit3 = (color_prom[i] >> 7) & 0x01;
+ g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+ bit0 = (color_prom[i + machine->drv->total_colors] >> 0) & 0x01;
+ bit1 = (color_prom[i + machine->drv->total_colors] >> 1) & 0x01;
+ bit2 = (color_prom[i + machine->drv->total_colors] >> 2) & 0x01;
+ bit3 = (color_prom[i + machine->drv->total_colors] >> 3) & 0x01;
+ b = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+
+ palette_set_color(machine,i,MAKE_RGB(r,g,b));
+ }
+}
+
+
+/***************************************************************************
+
+ Callbacks for the TileMap code
+
+***************************************************************************/
+
+static TILEMAP_MAPPER( get_fg_memory_offset )
+{
+ return (row ^ 0x1f) + (col << 5);
+}
+
+static TILEMAP_MAPPER( get_bg_memory_offset )
+{
+ return ((row & 0x0f) ^ 0x0f) | ((col & 0x0f) << 4) |
+ /* hole at bit 8 */
+ ((row & 0x10) << 5) | ((col & 0x10) << 6);
+}
+
+static TILE_GET_INFO( get_fg_tile_info )
+{
+ int code, color;
+
+ code = firetrap_fgvideoram[tile_index];
+ color = firetrap_fgvideoram[tile_index + 0x400];
+ SET_TILE_INFO(
+ 0,
+ code | ((color & 0x01) << 8),
+ color >> 4,
+ 0);
+}
+
+INLINE void get_bg_tile_info(running_machine *machine, tile_data *tileinfo, int tile_index, UINT8 *bgvideoram, int gfx_region)
+{
+ int code, color;
+
+ code = bgvideoram[tile_index];
+ color = bgvideoram[tile_index + 0x100];
+ SET_TILE_INFO(
+ gfx_region,
+ code + ((color & 0x03) << 8),
+ (color & 0x30) >> 4,
+ TILE_FLIPXY((color & 0x0c) >> 2));
+}
+
+static TILE_GET_INFO( get_bg1_tile_info )
+{
+ get_bg_tile_info(machine, tileinfo, tile_index, firetrap_bg1videoram, 1);
+}
+
+static TILE_GET_INFO( get_bg2_tile_info )
+{
+ get_bg_tile_info(machine, tileinfo, tile_index, firetrap_bg2videoram, 2);
+}
+
+
+/***************************************************************************
+
+ Start the video hardware emulation.
+
+***************************************************************************/
+
+VIDEO_START( firetrap )
+{
+ fg_tilemap = tilemap_create(get_fg_tile_info, get_fg_memory_offset,TILEMAP_TYPE_PEN, 8, 8,32,32);
+ bg1_tilemap = tilemap_create(get_bg1_tile_info,get_bg_memory_offset,TILEMAP_TYPE_PEN,16,16,32,32);
+ bg2_tilemap = tilemap_create(get_bg2_tile_info,get_bg_memory_offset,TILEMAP_TYPE_PEN, 16,16,32,32);
+
+ tilemap_set_transparent_pen(fg_tilemap,0);
+ tilemap_set_transparent_pen(bg1_tilemap,0);
+}
+
+
+/***************************************************************************
+
+ Memory handlers
+
+***************************************************************************/
+
+WRITE8_HANDLER( firetrap_fgvideoram_w )
+{
+ firetrap_fgvideoram[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap,offset & 0x3ff);
+}
+
+WRITE8_HANDLER( firetrap_bg1videoram_w )
+{
+ firetrap_bg1videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg1_tilemap,offset & 0x6ff);
+}
+
+WRITE8_HANDLER( firetrap_bg2videoram_w )
+{
+ firetrap_bg2videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg2_tilemap,offset & 0x6ff);
+}
+
+
+WRITE8_HANDLER( firetrap_bg1_scrollx_w )
+{
+ static UINT8 scroll[2];
+
+ scroll[offset] = data;
+ tilemap_set_scrollx(bg1_tilemap,0,scroll[0] | (scroll[1] << 8));
+}
+
+WRITE8_HANDLER( firetrap_bg1_scrolly_w )
+{
+ static UINT8 scroll[2];
+
+ scroll[offset] = data;
+ tilemap_set_scrolly(bg1_tilemap,0,-(scroll[0] | (scroll[1] << 8)));
+}
+
+WRITE8_HANDLER( firetrap_bg2_scrollx_w )
+{
+ static UINT8 scroll[2];
+
+ scroll[offset] = data;
+ tilemap_set_scrollx(bg2_tilemap,0,scroll[0] | (scroll[1] << 8));
+}
+
+WRITE8_HANDLER( firetrap_bg2_scrolly_w )
+{
+ static UINT8 scroll[2];
+
+ scroll[offset] = data;
+ tilemap_set_scrolly(bg2_tilemap,0,-(scroll[0] | (scroll[1] << 8)));
+}
+
+
+/***************************************************************************
+
+ Display refresh
+
+***************************************************************************/
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int offs;
+
+
+ for (offs = 0;offs < spriteram_size; offs += 4)
+ {
+ int sx,sy,flipx,flipy,code,color;
+
+
+ /* the meaning of bit 3 of [offs] is unknown */
+
+ sy = spriteram[offs];
+ sx = spriteram[offs + 2];
+ code = spriteram[offs + 3] + 4 * (spriteram[offs + 1] & 0xc0);
+ color = ((spriteram[offs + 1] & 0x08) >> 2) | (spriteram[offs + 1] & 0x01);
+ flipx = spriteram[offs + 1] & 0x04;
+ flipy = spriteram[offs + 1] & 0x02;
+ if (flip_screen)
+ {
+ sx = 240 - sx;
+ sy = 240 - sy;
+ flipx = !flipx;
+ flipy = !flipy;
+ }
+
+ if (spriteram[offs + 1] & 0x10) /* double width */
+ {
+ if (flip_screen) sy -= 16;
+
+ drawgfx(bitmap,machine->gfx[3],
+ code & ~1,
+ color,
+ flipx,flipy,
+ sx,flipy ? sy : sy + 16,
+ cliprect,TRANSPARENCY_PEN,0);
+ drawgfx(bitmap,machine->gfx[3],
+ code | 1,
+ color,
+ flipx,flipy,
+ sx,flipy ? sy + 16 : sy,
+ cliprect,TRANSPARENCY_PEN,0);
+
+ /* redraw with wraparound */
+ drawgfx(bitmap,machine->gfx[3],
+ code & ~1,
+ color,
+ flipx,flipy,
+ sx - 256,flipy ? sy : sy + 16,
+ cliprect,TRANSPARENCY_PEN,0);
+ drawgfx(bitmap,machine->gfx[3],
+ code | 1,
+ color,
+ flipx,flipy,
+ sx - 256,flipy ? sy + 16 : sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ else
+ {
+ drawgfx(bitmap,machine->gfx[3],
+ code,
+ color,
+ flipx,flipy,
+ sx,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+
+ /* redraw with wraparound */
+ drawgfx(bitmap,machine->gfx[3],
+ code,
+ color,
+ flipx,flipy,
+ sx - 256,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+}
+
+VIDEO_UPDATE( firetrap )
+{
+ tilemap_draw(bitmap,cliprect,bg2_tilemap,0,0);
+ tilemap_draw(bitmap,cliprect,bg1_tilemap,0,0);
+ draw_sprites(machine,bitmap,cliprect);
+ tilemap_draw(bitmap,cliprect,fg_tilemap,0,0);
+ return 0;
+}