From: "Yoda" <cedricbovar AT hotmail DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Using a doublebuffer with VESA 2.0
Date: Sat, 12 Feb 2000 15:51:36 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com


I'd like to use a double buffer . in the djgfx.html , it is written :

 unsigned char *videoptr = (unsigned char *)0x0;
 short our_global_selector = __dpmi_allocate_ldt_descriptors(1);
 __dpmi_set_segment_base_address(our_global_selector, linear_address);

 _farpokeb(our_global_selector, videoptr + y*width +x, color);

void copy_buffer2(void)
        {
   movedata(_my_ds(), doublebuffer, our_global_selector, videoptr,
width*height);
 }

I did the same but i get an error at the farpokeb or the movedata.
Actually it works for only 1 pixel !
If i try to copy the whole buffer into the screen it doesnt work.
If i try to farpoke another pixel then (0,0) it also doesnt work.

Can you help me to solve this prbl ? (in linear memory of course)