/*
==============================================================================
                      WordUp Graphics Toolkit Version 5.0                     
                             Demonstration Program 49                         
                                                                              
 This program will show how to use the wfade_between and wfade_between_once  
 commands. It will fade an image between the default palette and the image   
 palette.                                                                    
                                                                              
 *** PROJECT ***                                                             
 This program requires the WGT5_WC.LIB file to be linked.                    
                                                                              
 *** DATA FILES ***                                                          
 WGT1.PCX must be in the executable directory.                  
                                                           WATCOM C++ VERSION 
==============================================================================
*/

#include <stdlib.h>
#include <conio.h>
#include <wgt5.h>

void main (void)
{
  block myimage;                        /* Pointer to loaded image */
  color desired[256];                   /* Image palette */
  color defaultpal[256];                /* First copy of default palette */
  color backup_pal[256];                /* Second copy of default palette */
  short oldmode;                          /* Initial video mode */
  short ctr;                              /* Loop counter */

  if ( !vgadetected () )
  {
    printf ("Error - VGA card required for any WGT program.\n");
    exit (0);
  }
  printf ("WGT Example #49\n\n");
  printf ("The WFADE_BETWEEN command is demonstrated by fading from the default palette\n");
  printf ("to the image palette. Press a key to use the WFADE_BETWEEN_ONCE command so\n");
  printf ("that processing can be done while the fade is being performed.\n");
  printf ("\n\nPress any key to continue.\n");
  getch();


  oldmode = wgetmode ();                 /* Store current video mode     */
  vga256 ();                             /* Initialize WGT system        */

  myimage = wloadpcx ("wgt1.pcx", desired); /* Load the image */
  
  wreadpalette (0, 255, defaultpal);    /* Store default palette */
  wreadpalette (0, 255, backup_pal);    /* Store backup palette */

  wputblock (0, 0, myimage, NORMAL);    /* And show the image */

  wfade_between (0, 255, 20, defaultpal, desired);      /* Perform fade */
  getch ();

  /* We now need to use backup_pal since defaultpal has been changed to
     the values in "desired" */

  wtextcolor (15);                      /* Text is white */
  wtexttransparent (TEXTFGBG);          /* No transparencies */

  for (ctr = 0; ctr < 64; ctr++)        /* Do fades one step at a time */
  {
    wgtprintf (10, 180, NULL, "Fading - step #%d", ctr);
    wfade_between_once (0, 255, desired, backup_pal);   /* Perform fade */
    wsetpalette (0, 255, desired);      /* Show the changes */
    delay (40);                         /* Wait for a while */
  }
  getch ();

  wfreeblock (myimage);                 /* Deallocate the image */

  wsetmode (oldmode);                   /* Reset to text mode */
}