
      (* ************************************************************ *)
      (*                                                              *)
      (*                         DEMO7.PAS                            *)
      (*                                                              *)
      (*   This program provides an example of "zone-clearing." The   *)
      (*   The sprite is designed with trailing blanks which erase    *)
      (*   the previous image at the same time the new sprite is      *)
      (*   being placed on the screen at an advanced position. With   *)
      (*   this method neither Xor nor page-flipping is required for  *)
      (*   animation. Since it is simple it is also quite fast.       *)
      (*                                                              *)
      (*   Notice how increasing delays affect the result. You might  *)
      (*   also see how increases or decreases in the size of the     *)
      (*   zone of trailing blanks affect the resultant animation.    *)
      (*   Take a look at the sprite (zone.spr) using the sprite      *)
      (*   editor (Designer.com).                                     *)
      (*                                                              *)
      (*                              (c) Donald L. Pavia             *)
      (*          Ver 1.0             Department of Chemistry         *)
      (*       February 1986          Western Washington University   *)
      (*                              Bellingham, Washington 98225    *)
      (*                                                              *)
      (* ************************************************************ *)


program SpriteDemo7;
                                  { Try changing j to 25 and k to 12 from }
const  j = 75; k = 4;             { 75 and 4, respectively. Then change   }
                                  { zone1.spr to zone2.spr                }
var    i : integer;

{----------------------------------------------------------------------------}
{$I Sprites.Lib}
{----------------------------------------------------------------------------}

BEGIN
     clrscr;
     GraphColorMode; GraphBackGround (1); Palette (2);

     LoadSprite ('Zone1.spr');        { loads sprite into var TempSprite   }

     gotoxy (2,1); write ('Press <ENTER> ');
     read (Kbd,Wait);
     gotoxy (2,1); write ('              ');

     Sprite := TempSprite;           { assign TempSprite as active sprite }

     for i := 1 to j do begin
          PutSpriteC (k*i,50);  Delay (0);   end;
     for i := 1 to j do begin
          PutSpriteC (k*i,75);  Delay (25);  end;
     for i := 1 to j do begin
          PutSpriteC (k*i,100); Delay (50);  end;
     for i := 1 to j do begin
          PutSpriteC (k*i,125); Delay (100); end;
     for i := 1 to j do begin
          PutSpriteC (k*i,150); Delay (150); end;

     read (Kbd,Wait);
     TextMode (c80);

END.
