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-rw-r--r--src/mame/video/xybots.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/src/mame/video/xybots.c b/src/mame/video/xybots.c
new file mode 100644
index 00000000000..f965f06a03c
--- /dev/null
+++ b/src/mame/video/xybots.c
@@ -0,0 +1,166 @@
+/***************************************************************************
+
+ Atari Xybots hardware
+
+****************************************************************************/
+
+#include "driver.h"
+#include "machine/atarigen.h"
+#include "includes/xybots.h"
+
+
+
+/*************************************
+ *
+ * Tilemap callbacks
+ *
+ *************************************/
+
+static TILE_GET_INFO( get_alpha_tile_info )
+{
+ UINT16 data = atarigen_alpha[tile_index];
+ int code = data & 0x3ff;
+ int color = (data >> 12) & 7;
+ int opaque = data & 0x8000;
+ SET_TILE_INFO(2, code, color, opaque ? TILE_FORCE_LAYER0 : 0);
+}
+
+
+static TILE_GET_INFO( get_playfield_tile_info )
+{
+ UINT16 data = atarigen_playfield[tile_index];
+ int code = data & 0x1fff;
+ int color = (data >> 11) & 0x0f;
+ SET_TILE_INFO(0, code, color, (data >> 15) & 1);
+}
+
+
+
+/*************************************
+ *
+ * Video system start
+ *
+ *************************************/
+
+VIDEO_START( xybots )
+{
+ static const struct atarimo_desc modesc =
+ {
+ 1, /* index to which gfx system */
+ 1, /* number of motion object banks */
+ 0, /* are the entries linked? */
+ 0, /* 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? */
+ 0, /* pixels per SLIP entry (0 for no-slip) */
+ 0, /* pixel offset for SLIPs */
+ 0, /* maximum number of links to visit/scanline (0=all) */
+
+ 0x100, /* base palette entry */
+ 0x300, /* maximum number of colors */
+ 0, /* transparent pen index */
+
+ {{ 0x3f }}, /* mask for the link (dummy) */
+ {{ 0 }}, /* mask for the graphics bank */
+ {{ 0x3fff,0,0,0 }}, /* mask for the code index */
+ {{ 0 }}, /* mask for the upper code index */
+ {{ 0,0,0,0x000f }}, /* mask for the color */
+ {{ 0,0,0,0xff80 }}, /* mask for the X position */
+ {{ 0,0,0xff80,0 }}, /* mask for the Y position */
+ {{ 0 }}, /* mask for the width, in tiles*/
+ {{ 0,0,0x0007,0 }}, /* mask for the height, in tiles */
+ {{ 0x8000,0,0,0 }}, /* mask for the horizontal flip */
+ {{ 0 }}, /* mask for the vertical flip */
+ {{ 0,0x000f,0,0 }}, /* 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" */
+ NULL /* callback routine for special entries */
+ };
+
+ /* initialize the playfield */
+ atarigen_playfield_tilemap = tilemap_create(get_playfield_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8,8, 64,32);
+
+ /* 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);
+}
+
+
+
+/*************************************
+ *
+ * Main refresh
+ *
+ *************************************/
+
+VIDEO_UPDATE( xybots )
+{
+ 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:
+
+ PRIEN = ~(~MOPIX3 & ~MOPIX2 & ~MOPIX1) = (MOPIX3-0 > 1)
+
+ if (PRIEN)
+ PF/MO = (~MOPRI3-0 > PFCOL3-0)
+ else
+ PF/MO = (~MOPRI3-0 >= PFCOL3-0)
+
+ if (PF/MO | ~(PRIEN & MOCOL3))
+ GPC(P3-0) = PFPIX3-0
+ else
+ GPC(P3-0) = ~MOCOL3-0
+ */
+ int mopriority = (mo[x] >> ATARIMO_PRIORITY_SHIFT) ^ 15;
+ int pfcolor = (pf[x] >> 4) & 0x0f;
+ int prien = ((mo[x] & 0x0f) > 1);
+
+ if (prien)
+ {
+ if (mopriority <= pfcolor)
+ {
+ /* this first case doesn't make sense from the schematics, but it has */
+ /* the correct effect */
+ if (mo[x] & 0x80)
+ pf[x] = (mo[x] ^ 0x2f0) & ATARIMO_DATA_MASK;
+ else
+ pf[x] = mo[x] & ATARIMO_DATA_MASK;
+ }
+ }
+ else
+ {
+ if (mopriority < pfcolor)
+ pf[x] = mo[x] & ATARIMO_DATA_MASK;
+ }
+
+ /* erase behind ourselves */
+ mo[x] = 0;
+ }
+ }
+
+ /* add the alpha on top */
+ tilemap_draw(bitmap, cliprect, atarigen_alpha_tilemap, 0, 0);
+ return 0;
+}