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     Date: 11-15-95    Time: 09:22p     Number: 1412   
     From: andrew clarke                 Refer:         
       To: Elliot Tobin               Board ID: FIX             Reply: 
  Subject: Hey!                            132: fido.en.c_ec   Status: Public 
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 >     Does anybod have some code on fading in and out?

/*
    fadethng.c; fade da VGA screen in and out.
    Copyright (c) 1995 by Andrew Clarke.  Based on code by Mike Jabour.
    Released to the public domain.
*/

#include 
#include 

unsigned char pal[256][3];

void set_mcga(void)
{
    _asm {
        mov    ax,0x0013
        int    0x10
    }
}

void set_text(void)
{
    _asm {
        mov    ax,0x0003
        int    0x10
    }
}

void wait_retrace(void)
{
    _asm {
        mov    dx,0x03da
    }

l1:
    _asm {
        in     al,dx
        and    al,0x08
        jnz    l1
    }

l2:
    _asm {
        in     al,dx
        and    al,0x08
        jz     l2
    }
}

void get_pal(unsigned char color_no, unsigned char *r, unsigned char *g,
unsigned char *b)
{
    outp(0x03c7, color_no);
    *r = (unsigned char) inp(0x3c9);
    *g = (unsigned char) inp(0x3c9);
    *b = (unsigned char) inp(0x3c9);
}

void set_pal(unsigned char color_no, unsigned char r, unsigned char g, unsigned
char b)
{
    outp(0x03c8, color_no);
    outp(0x3c9, r);
    outp(0x3c9, g);
    outp(0x3c9, b);
}

void fade_up(void)
{
    unsigned char i, j, tmp[3];

    for(i = 1; i < 64; i++) {
        wait_retrace();
        for(j = 0; j < 255; j++) {
            get_pal(j, &tmp[0], &tmp[1], &tmp[2]);
            if (tmp[0] < pal[j][0])
                tmp[0]++;
            if (tmp[1] < pal[j][1])
                tmp[1]++;
            if (tmp[2] < pal[j][2])
                tmp[2]++;
            set_pal(j, tmp[0], tmp[1], tmp[2]);
        }
    }
}

void fade_down(void)
{
    unsigned char i, j, tmp[3];

    for(i = 1; i < 64; i++) {
        wait_retrace();
        for(j = 0; j < 255; j++) {
            get_pal(j, &tmp[0], &tmp[1], &tmp[2]);
            if (tmp[0])
                tmp[0]--;
            if (tmp[1])
                tmp[1]--;
            if (tmp[2])
                tmp[2]--;
            set_pal(j, tmp[0], tmp[1], tmp[2]);
        }

    }
}

void save_palette(void)
{
    unsigned char i, j;

    for(i = 1; i < 64; i++) {
        wait_retrace();
        for(j = 0; j < 255; j++) {
            get_pal(j, &pal[j][0], &pal[j][1], &pal[j][2]);
        }

    }
}

int main(void)
{
    save_palette();
    fade_down();
    getch();
    fade_up();
    return 0;
}

--- Msgedsq/2 3.20
 * Origin: Blizzard of Ozz, Melbourne, Australia (3:635/727.4@fidonet)
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