bm

program BumpMapper;

Uses Crt,Dos,TJVga; { This file won't compile without TJVga, haha }

Type ronne=Array[0..255,0..254]of byte; { The environmentmap array }
    rptr=^ronne;                        { Same, but pointer }

Var environmentmap:rptr;
    i,j:integer;
    mx,my:integer;      { Light position  }
    xdir,ydir:integer;
    VirScr2:VirtPtr; { The second virtual screen, used for the bumpmap }
    Vaddr2:word;

Procedure CreateEnvironmentMap;     { Guess??? }
Var I,J:Integer;
  nx,ny,nz:real;
begin
getmem(environmentmap,sizeof(environmentmap^));  { Biggos pointeros }
for i := 0 to 255 do                             { Very slooooow }
 for j := 0 to 254 do begin
   nX:=(i-128)/128;
   nY:=(j-128)/128;
   nZ:=1-sqrt(nX*nX+nY*nY);
   if nz<0 then nZ:=0;
   environmentmap^[i,j]:=Round(nZ*128);
  end;
end;

Procedure Bumpmap(lightx,lighty:integer);
var xtemp,ytemp,temp,i,j:integer;
     nx,ny:integer;
begin
for i := 0 to 319 do
for j := 1 to 198 do begin {Skip the first and last line, cause they look bad}
  nx:=getpixel(i-1,j,vaddr2)-getpixel(i+1,j,vaddr2);
  ny:=getpixel(i,j-1,vaddr2)-getpixel(i,j+1,vaddr2);
  asm
   mov ax,i
   sub ax,lightx         { xtemp:=i-lightx;}
   mov xtemp,ax
   mov ax,j
   sub ax,lighty         {  ytemp:=j-lighty;}
   mov ytemp,ax
   mov ax,nx
   sub ax,xtemp          {   dec(nx,xtemp);}
   mov nx,ax
   mov ax,ny
   sub ax,ytemp          {   dec(ny,ytemp);}
   mov ny,ax
   mov ax,nx
   add ax,128            {   inc(nx,128); }
   mov nx,ax
   mov ax,ny
   add ax,128             {  inc(ny,128;}
   mov ny,ax
  end;

  if (nx<0) or (nx>255) then nx:=0; { Check ranges }
  if (ny<0) or (ny>255) then ny:=0;
  putpixel(i,j,environmentmap^[nx,ny],vaddr); { Put the pixel }
 end;
end;

begin
Writeln('[Creating Environment map]');
CreateEnvironmentMap; { Bla,bla}
Writeln('Done.');
SetMCGA; { Init the graphics mode }
mx:=160;              { Start position of the light }
my:=100;
SetupVirtual;     { Init virtual screens}
getmem(virscr2,sizeof(virscr2^));
vaddr2:=seg(virscr2^);
cls(vaddr,0);
LoadPCX('bumpmap.pcx',0,0,Vaddr2); { Load the PCX-file to use as bumpmap }
for i := 0 to 63 do                { Set the fire palette }
 pal(i,i,0,0);
for i := 64 to 127 do
 pal(i,63,i-64,0);
for i := 128 to 255 do
 pal(i,63,63,i div 4);
xdir:=4;
ydir:=-4;
repeat
BumpMap(mx,my);
flip(vaddr,vga);
inc(mx,xdir);
inc(my,ydir);
if mx<0 then xdir:=-xdir;
if mx>319 then xdir:=-xdir;
if my<0 then ydir:=-ydir;
if my>199 then ydir:=-ydir;
until keypressed;
freemem(environmentmap,sizeof(environmentmap^));
freemem(virscr2,sizeof(virscr2^));
ShutDown; { Deallocate virtual screen }
SetText;  { Set text mode }
Writeln('TJ -1998');
end.