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-rw-r--r--src/mame/video/subs.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/src/mame/video/subs.c b/src/mame/video/subs.c
new file mode 100644
index 00000000000..fd36fc86f80
--- /dev/null
+++ b/src/mame/video/subs.c
@@ -0,0 +1,163 @@
+/***************************************************************************
+
+ Atari Subs hardware
+
+***************************************************************************/
+
+#include "driver.h"
+#include "subs.h"
+#include "sound/discrete.h"
+
+WRITE8_HANDLER( subs_invert1_w )
+{
+ if ((offset & 0x01) == 1)
+ {
+ palette_set_color(Machine, 0, MAKE_RGB(0x00, 0x00, 0x00));
+ palette_set_color(Machine, 1, MAKE_RGB(0xFF, 0xFF, 0xFF));
+ }
+ else
+ {
+ palette_set_color(Machine, 1, MAKE_RGB(0x00, 0x00, 0x00));
+ palette_set_color(Machine, 0, MAKE_RGB(0xFF, 0xFF, 0xFF));
+ }
+}
+
+WRITE8_HANDLER( subs_invert2_w )
+{
+ if ((offset & 0x01) == 1)
+ {
+ palette_set_color(Machine, 2, MAKE_RGB(0x00, 0x00, 0x00));
+ palette_set_color(Machine, 3, MAKE_RGB(0xFF, 0xFF, 0xFF));
+ }
+ else
+ {
+ palette_set_color(Machine, 3, MAKE_RGB(0x00, 0x00, 0x00));
+ palette_set_color(Machine, 2, MAKE_RGB(0xFF, 0xFF, 0xFF));
+ }
+}
+
+
+VIDEO_UPDATE( subs )
+{
+ int offs;
+
+ /* for every character in the Video RAM, check if it has been modified */
+ /* since last time and update it accordingly. */
+ for (offs = videoram_size - 1;offs >= 0;offs--)
+ {
+ int charcode;
+ int sx,sy;
+ int left_enable,right_enable;
+ int left_sonar_window,right_sonar_window;
+
+ left_sonar_window = 0;
+ right_sonar_window = 0;
+
+ charcode = videoram[offs];
+
+ /* Which monitor is this for? */
+ right_enable = charcode & 0x40;
+ left_enable = charcode & 0x80;
+
+ sx = 8 * (offs % 32);
+ sy = 8 * (offs / 32);
+
+ /* Special hardware logic for sonar windows */
+ if ((sy >= (128+64)) && (sx < 32))
+ left_sonar_window = 1;
+ else if ((sy >= (128+64)) && (sx >= (128+64+32)))
+ right_sonar_window = 1;
+ else
+ charcode = charcode & 0x3F;
+
+ /* Draw the left screen */
+ if (screen==0)
+ {
+ if ((left_enable || left_sonar_window) && (!right_sonar_window))
+ {
+ drawgfx(bitmap,machine->gfx[0],
+ charcode, 1,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_NONE,0);
+ }
+ else
+ {
+ drawgfx(bitmap,machine->gfx[0],
+ 0, 1,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_NONE,0);
+ }
+ }
+
+ /* Draw the right screen */
+ if (screen==1)
+ {
+ if ((right_enable || right_sonar_window) && (!left_sonar_window))
+ {
+ drawgfx(bitmap,machine->gfx[0],
+ charcode, 0,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_NONE,0);
+ }
+ else
+ {
+ drawgfx(bitmap,machine->gfx[0],
+ 0, 0,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_NONE,0);
+ }
+ }
+ }
+
+ /* draw the motion objects */
+ for (offs = 0; offs < 4; offs++)
+ {
+ int sx,sy;
+ int charcode;
+ int prom_set;
+ int sub_enable;
+
+ sx = spriteram[0x00 + (offs * 2)] - 16;
+ sy = spriteram[0x08 + (offs * 2)] - 16;
+ charcode = spriteram[0x09 + (offs * 2)];
+ if (offs < 2)
+ sub_enable = spriteram[0x01 + (offs * 2)] & 0x80;
+ else
+ sub_enable = 1;
+
+ prom_set = charcode & 0x01;
+ charcode = (charcode >> 3) & 0x1F;
+
+ /* Left screen - special check for drawing right screen's sub */
+ if (screen==0)
+ {
+ if ((offs!=0) || (sub_enable))
+ {
+ drawgfx(bitmap,machine->gfx[1],
+ charcode + 32 * prom_set,
+ 0,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+
+
+ /* Right screen - special check for drawing left screen's sub */
+ if (screen==1)
+ {
+ if ((offs!=1) || (sub_enable))
+ {
+ drawgfx(bitmap,machine->gfx[1],
+ charcode + 32 * prom_set,
+ 0,
+ 0,0,sx,sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+ }
+
+ /* Update sound */
+ discrete_sound_w(SUBS_LAUNCH_DATA, spriteram[5] & 0x0f); // Launch data
+ discrete_sound_w(SUBS_CRASH_DATA, spriteram[5] >> 4); // Crash/explode data
+ return 0;
+}