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-rw-r--r--src/mame/video/gauntlet.c230
1 files changed, 230 insertions, 0 deletions
diff --git a/src/mame/video/gauntlet.c b/src/mame/video/gauntlet.c
new file mode 100644
index 00000000000..2a0cbc636de
--- /dev/null
+++ b/src/mame/video/gauntlet.c
@@ -0,0 +1,230 @@
+/***************************************************************************
+
+ Atari Gauntlet hardware
+
+****************************************************************************/
+
+#include "driver.h"
+#include "machine/atarigen.h"
+#include "gauntlet.h"
+
+
+
+/*************************************
+ *
+ * Globals we own
+ *
+ *************************************/
+
+UINT8 vindctr2_screen_refresh;
+
+
+
+/*************************************
+ *
+ * Statics
+ *
+ *************************************/
+
+static UINT8 playfield_tile_bank;
+static UINT8 playfield_color_bank;
+
+
+
+/*************************************
+ *
+ * Tilemap callbacks
+ *
+ *************************************/
+
+static TILE_GET_INFO( get_alpha_tile_info )
+{
+ UINT16 data = atarigen_alpha[tile_index];
+ int code = data & 0x3ff;
+ int color = ((data >> 10) & 0x0f) | ((data >> 9) & 0x20);
+ int opaque = data & 0x8000;
+ SET_TILE_INFO(1, code, color, opaque ? TILE_FORCE_LAYER0 : 0);
+}
+
+
+static TILE_GET_INFO( get_playfield_tile_info )
+{
+ UINT16 data = atarigen_playfield[tile_index];
+ int code = ((playfield_tile_bank * 0x1000) + (data & 0xfff)) ^ 0x800;
+ int color = 0x10 + (playfield_color_bank * 8) + ((data >> 12) & 7);
+ SET_TILE_INFO(0, code, color, (data >> 15) & 1);
+}
+
+
+
+/*************************************
+ *
+ * Video system start
+ *
+ *************************************/
+
+VIDEO_START( gauntlet )
+{
+ static const struct atarimo_desc modesc =
+ {
+ 0, /* index to which gfx system */
+ 1, /* number of motion object banks */
+ 1, /* are the entries linked? */
+ 1, /* are the entries split? */
+ 0, /* render in reverse order? */
+ 0, /* render in swapped X/Y order? */
+ 0, /* does the neighbor bit affect the next object? */
+ 8, /* pixels per SLIP entry (0 for no-slip) */
+ 1, /* pixel offset for SLIPs */
+ 0, /* maximum number of links to visit/scanline (0=all) */
+
+ 0x100, /* base palette entry */
+ 0x100, /* maximum number of colors */
+ 0, /* transparent pen index */
+
+ {{ 0,0,0,0x03ff }}, /* mask for the link */
+ {{ 0 }}, /* mask for the graphics bank */
+ {{ 0x7fff,0,0,0 }}, /* mask for the code index */
+ {{ 0 }}, /* mask for the upper code index */
+ {{ 0,0x000f,0,0 }}, /* mask for the color */
+ {{ 0,0xff80,0,0 }}, /* mask for the X position */
+ {{ 0,0,0xff80,0 }}, /* mask for the Y position */
+ {{ 0,0,0x0038,0 }}, /* mask for the width, in tiles*/
+ {{ 0,0,0x0007,0 }}, /* mask for the height, in tiles */
+ {{ 0,0,0x0040,0 }}, /* mask for the horizontal flip */
+ {{ 0 }}, /* mask for the vertical flip */
+ {{ 0 }}, /* mask for the priority */
+ {{ 0 }}, /* mask for the neighbor */
+ {{ 0 }}, /* mask for absolute coordinates */
+
+ {{ 0 }}, /* mask for the special value */
+ 0, /* resulting value to indicate "special" */
+ 0 /* callback routine for special entries */
+ };
+
+ UINT16 *codelookup;
+ int i, size;
+
+ /* initialize the playfield */
+ atarigen_playfield_tilemap = tilemap_create(get_playfield_tile_info, tilemap_scan_cols, TILEMAP_TYPE_PEN, 8,8, 64,64);
+
+ /* initialize the motion objects */
+ atarimo_init(machine, 0, &modesc);
+
+ /* initialize the alphanumerics */
+ atarigen_alpha_tilemap = tilemap_create(get_alpha_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8,8, 64,32);
+ tilemap_set_transparent_pen(atarigen_alpha_tilemap, 0);
+
+ /* modify the motion object code lookup table to account for the code XOR */
+ codelookup = atarimo_get_code_lookup(0, &size);
+ for (i = 0; i < size; i++)
+ codelookup[i] ^= 0x800;
+
+ /* set up the base color for the playfield */
+ playfield_color_bank = vindctr2_screen_refresh ? 0 : 1;
+}
+
+
+
+/*************************************
+ *
+ * Horizontal scroll register
+ *
+ *************************************/
+
+WRITE16_HANDLER( gauntlet_xscroll_w )
+{
+ UINT16 oldxscroll = *atarigen_xscroll;
+ COMBINE_DATA(atarigen_xscroll);
+
+ /* if something changed, force a partial update */
+ if (*atarigen_xscroll != oldxscroll)
+ {
+ video_screen_update_partial(0, video_screen_get_vpos(0));
+
+ /* adjust the scrolls */
+ tilemap_set_scrollx(atarigen_playfield_tilemap, 0, *atarigen_xscroll);
+ atarimo_set_xscroll(0, *atarigen_xscroll & 0x1ff);
+ }
+}
+
+
+
+/*************************************
+ *
+ * Vertical scroll/PF bank register
+ *
+ *************************************/
+
+WRITE16_HANDLER( gauntlet_yscroll_w )
+{
+ UINT16 oldyscroll = *atarigen_yscroll;
+ COMBINE_DATA(atarigen_yscroll);
+
+ /* if something changed, force a partial update */
+ if (*atarigen_yscroll != oldyscroll)
+ {
+ video_screen_update_partial(0, video_screen_get_vpos(0));
+
+ /* if the bank changed, mark all tiles dirty */
+ if (playfield_tile_bank != (*atarigen_yscroll & 3))
+ {
+ playfield_tile_bank = *atarigen_yscroll & 3;
+ tilemap_mark_all_tiles_dirty(atarigen_playfield_tilemap);
+ }
+
+ /* adjust the scrolls */
+ tilemap_set_scrolly(atarigen_playfield_tilemap, 0, *atarigen_yscroll >> 7);
+ atarimo_set_yscroll(0, (*atarigen_yscroll >> 7) & 0x1ff);
+ }
+}
+
+
+
+/*************************************
+ *
+ * Main refresh
+ *
+ *************************************/
+
+VIDEO_UPDATE( gauntlet )
+{
+ struct atarimo_rect_list rectlist;
+ mame_bitmap *mobitmap;
+ int x, y, r;
+
+ /* draw the playfield */
+ tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 0, 0);
+
+ /* draw and merge the MO */
+ mobitmap = atarimo_render(machine, 0, cliprect, &rectlist);
+ for (r = 0; r < rectlist.numrects; r++, rectlist.rect++)
+ for (y = rectlist.rect->min_y; y <= rectlist.rect->max_y; y++)
+ {
+ UINT16 *mo = (UINT16 *)mobitmap->base + mobitmap->rowpixels * y;
+ UINT16 *pf = (UINT16 *)bitmap->base + bitmap->rowpixels * y;
+ for (x = rectlist.rect->min_x; x <= rectlist.rect->max_x; x++)
+ if (mo[x])
+ {
+ /* verified via schematics:
+
+ MO pen 1 clears PF color bit 0x80
+ */
+ if ((mo[x] & 0x0f) == 1)
+ {
+ /* Vindicators Part II has extra logic here for the bases */
+ if (!vindctr2_screen_refresh || (mo[x] & 0xf0) != 0)
+ pf[x] ^= 0x80;
+ }
+ else
+ pf[x] = mo[x];
+
+ /* erase behind ourselves */
+ mo[x] = 0;
+ }
+ }
+
+ /* add the alpha on top */
+ tilemap_draw(bitmap, cliprect, atarigen_alpha_tilemap, 0, 0);
+ return 0;
+}