backported g3d changes:

[dosdemo] / src / dos / gfx.h

diff --git a/src/dos/gfx.h b/src/dos/gfx.h
index 941f05c..109bbcf 100644 (file)
--- a/src/dos/gfx.h
+++ b/src/dos/gfx.h
@@ -1,20 +1,3 @@
-/*
-colcycle - color cycling image viewer
-Copyright (C) 2016  John Tsiombikas <nuclear@member.fsf.org>
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
 #ifndef GFX_H_
 #define GFX_H_
 
@@ -32,7 +15,43 @@ int get_color_mask(unsigned int *rmask, unsigned int *gmask, unsigned int *bmask
 
 void set_palette(int idx, int r, int g, int b);
 
+enum {
+       FLIP_NOW,
+       FLIP_VBLANK,
+       FLIP_VBLANK_WAIT
+};
+/* page flip and return pointer to the start of the display area (front buffer) */
+void *page_flip(int vsync);
+
+#ifdef __WATCOMC__
 void wait_vsync(void);
+#pragma aux wait_vsync = \
+       "mov dx, 0x3da" \
+       "l1:" \
+       "in al, dx" \
+       "and al, 0x8" \
+       "jnz l1" \
+       "l2:" \
+       "in al, dx" \
+       "and al, 0x8" \
+       "jz l2" \
+       modify[al dx];
+#endif
+
+#ifdef __DJGPP__
+#define wait_vsync()  asm volatile ( \
+       "mov $0x3da, %%dx\n\t" \
+       "0:\n\t" \
+       "in %%dx, %%al\n\t" \
+       "and $8, %%al\n\t" \
+       "jnz 0b\n\t" \
+       "0:\n\t" \
+       "in %%dx, %%al\n\t" \
+       "and $8, %%al\n\t" \
+       "jz 0b\n\t" \
+       :::"%eax","%edx")
+#endif
+
 
 #ifdef __cplusplus
 }