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{$G+}
program flames;
uses crt;
{**************************************************************************}
{* *}
{* FLAMES by M.D.Mackey (C) 1993 *}
{* This code released into the public domain. It may be freely *}
{* used, distributed and modified. I would appreciate it if *}
{* credit were given, however. If you have any improvements, *}
{* find any bugs etc. mail me at mackey@aqueous.ml.csiro.au *}
{* with MARK: in the subject header. *}
{* *}
{**************************************************************************}
{**************************************************************************}
{* *}
{* Modified 12-Dec-93: John M. Beck *}
{* *}
{* Restructured and added wave effect by tracing sin path. *}
{* *}
{**************************************************************************}
const palette : array [1..768] of byte = (
0, 0, 0, 0, 0, 24, 0, 0, 24, 0, 0, 28,
0, 0, 32, 0, 0, 32, 0, 0, 36, 0, 0, 40,
8, 0, 40, 16, 0, 36, 24, 0, 36, 32, 0, 32,
40, 0, 28, 48, 0, 28, 56, 0, 24, 64, 0, 20,
72, 0, 20, 80, 0, 16, 88, 0, 16, 96, 0, 12,
104, 0, 8, 112, 0, 8, 120, 0, 4, 128, 0, 0,
128, 0, 0, 132, 0, 0, 136, 0, 0, 140, 0, 0,
144, 0, 0, 144, 0, 0, 148, 0, 0, 152, 0, 0,
156, 0, 0, 160, 0, 0, 160, 0, 0, 164, 0, 0,
168, 0, 0, 172, 0, 0, 176, 0, 0, 180, 0, 0,
184, 4, 0, 188, 4, 0, 192, 8, 0, 196, 8, 0,
200, 12, 0, 204, 12, 0, 208, 16, 0, 212, 16, 0,
216, 20, 0, 220, 20, 0, 224, 24, 0, 228, 24, 0,
232, 28, 0, 236, 28, 0, 240, 32, 0, 244, 32, 0,
252, 36, 0, 252, 36, 0, 252, 40, 0, 252, 40, 0,
252, 44, 0, 252, 44, 0, 252, 48, 0, 252, 48, 0,
252, 52, 0, 252, 52, 0, 252, 56, 0, 252, 56, 0,
252, 60, 0, 252, 60, 0, 252, 64, 0, 252, 64, 0,
252, 68, 0, 252, 68, 0, 252, 72, 0, 252, 72, 0,
252, 76, 0, 252, 76, 0, 252, 80, 0, 252, 80, 0,
252, 84, 0, 252, 84, 0, 252, 88, 0, 252, 88, 0,
252, 92, 0, 252, 96, 0, 252, 96, 0, 252, 100, 0,
252, 100, 0, 252, 104, 0, 252, 104, 0, 252, 108, 0,
252, 108, 0, 252, 112, 0, 252, 112, 0, 252, 116, 0,
252, 116, 0, 252, 120, 0, 252, 120, 0, 252, 124, 0,
252, 124, 0, 252, 128, 0, 252, 128, 0, 252, 132, 0,
252, 132, 0, 252, 136, 0, 252, 136, 0, 252, 140, 0,
252, 140, 0, 252, 144, 0, 252, 144, 0, 252, 148, 0,
252, 152, 0, 252, 152, 0, 252, 156, 0, 252, 156, 0,
252, 160, 0, 252, 160, 0, 252, 164, 0, 252, 164, 0,
252, 168, 0, 252, 168, 0, 252, 172, 0, 252, 172, 0,
252, 176, 0, 252, 176, 0, 252, 180, 0, 252, 180, 0,
252, 184, 0, 252, 184, 0, 252, 188, 0, 252, 188, 0,
252, 192, 0, 252, 192, 0, 252, 196, 0, 252, 196, 0,
252, 200, 0, 252, 200, 0, 252, 204, 0, 252, 208, 0,
252, 208, 0, 252, 208, 0, 252, 208, 0, 252, 208, 0,
252, 212, 0, 252, 212, 0, 252, 212, 0, 252, 212, 0,
252, 216, 0, 252, 216, 0, 252, 216, 0, 252, 216, 0,
252, 216, 0, 252, 220, 0, 252, 220, 0, 252, 220, 0,
252, 220, 0, 252, 224, 0, 252, 224, 0, 252, 224, 0,
252, 224, 0, 252, 228, 0, 252, 228, 0, 252, 228, 0,
252, 228, 0, 252, 228, 0, 252, 232, 0, 252, 232, 0,
252, 232, 0, 252, 232, 0, 252, 236, 0, 252, 236, 0,
252, 236, 0, 252, 236, 0, 252, 240, 0, 252, 240, 0,
252, 244, 0, 252, 244, 0, 252, 244, 0, 252, 248, 0,
252, 248, 0, 252, 248, 0, 252, 248, 0, 252, 252, 0,
252, 252, 4, 252, 252, 8, 252, 252, 12, 252, 252, 16,
252, 252, 20, 252, 252, 24, 252, 252, 28, 252, 252, 32,
252, 252, 36, 252, 252, 40, 252, 252, 40, 252, 252, 44,
252, 252, 48, 252, 252, 52, 252, 252, 56, 252, 252, 60,
252, 252, 64, 252, 252, 68, 252, 252, 72, 252, 252, 76,
252, 252, 80, 252, 252, 84, 252, 252, 84, 252, 252, 88,
252, 252, 92, 252, 252, 96, 252, 252, 100, 252, 252, 104,
252, 252, 108, 252, 252, 112, 252, 252, 116, 252, 252, 120,
252, 252, 124, 252, 252, 124, 252, 252, 128, 252, 252, 132,
252, 252, 136, 252, 252, 140, 252, 252, 144, 252, 252, 148,
252, 252, 152, 252, 252, 156, 252, 252, 160, 252, 252, 164,
252, 252, 168, 252, 252, 168, 252, 252, 172, 252, 252, 176,
252, 252, 180, 252, 252, 184, 252, 252, 188, 252, 252, 192,
252, 252, 196, 252, 252, 200, 252, 252, 204, 252, 252, 208,
252, 252, 208, 252, 252, 212, 252, 252, 216, 252, 252, 220,
252, 252, 224, 252, 252, 228, 252, 252, 232, 252, 252, 236,
252, 252, 240, 252, 252, 244, 252, 252, 248, 252, 252, 252,
252, 252, 240, 252, 252, 244, 252, 252, 248, 252, 252, 252);
radius = 1.9;
frequency = 2;
angleinc = 3 * pi / frequency;
var
count : word;
delta : integer;
path : array[0..199] of word;
buffer : array[0..102,0..159] of integer;
procedure buildpath;
var
count : byte;
currangle : real;
begin
currangle := pi;
for count := 0 to 199 do
begin
path[count] := 320 + round(radius*sin(currangle));
{ the sin path _must_ lie on an even number }
{ otherwise the picture will be garbage }
if path[count] mod 2 <> 0 then
if path[count] > 320 then
dec(path[count]) { round down }
else
inc(path[count]); { round up }
{ the path is rounded to the closest even number to 320 }
currangle := currangle + angleinc;
end;
end;
begin
randomize;
buildpath;
asm
mov ax,13h { ; AX := 13h }
int 10h { ; Set Mode 13h (320x200x256) }
xor ax,ax { ; AX := 0 }
mov cx,768 { ; CX := # of palette entries }
mov dx,03C8h { ; DX := VGA Port }
mov si,offset palette { ; SI := palette[0] }
out dx,al { ; send zero to index port }
inc dx { ; inc to write port }
@l1:
mov bl,[si] { ; set palette entry }
shr bl,2 { ; divide by 4 }
mov [si],bl { ; save entry }
outsb { ; and write to port }
dec cx { ; CX := CX - 1 }
jnz @l1 { ; if not done then loop }
mov ax,seg buffer { ; AX := segment of buffer }
mov es,ax { ; ES := AX }
mov di,offset buffer { ; DI := buffer[0] }
mov cx,8109 { ; CX := sizeof(buffer) div 2 }
xor ax,ax { ; AX := 0 }
rep stosw { ; clear every element in buffer to zero}
end;
repeat
asm
mov bx,1 { ; BX := 1 }
mov si,offset path { ; SI := path[0] }
mov cx,16160 { ; CX := # of elements to change }
mov di,offset buffer { ; DI := buffer[0] }
add di,320 { ; DI := buffer[320] (0,1) }
@l2:
mov ax,ds:[di-2] { ; AX := buffer[DI-2] (x-1,y) }
add ax,ds:[di] { ; AX += buffer[DI] (x ,y) }
add ax,ds:[di+2] { ; AX += buffer[DI+2] (x+1,y) }
add ax,ds:[di+320] { ; AX += buffer[DI+320] (x,y+1) }
shr ax,2 { ; AX := AX div 4 (calc average) }
jz @l3 { ; if AX = 0 then skip next line }
dec ax { ; else AX-- }
@l3:
push di { ; save DI }
sub di,ds:[si] { ; DI := (x + or - sin,y-1) }
mov word ptr ds:[di],ax { store AX somewhere one line up }
pop di { ; restore DI }
inc di { ; DI++ }
inc di { ; DI++ (move to next word) }
inc bx { ; BX++ }
cmp bx,320 { ; if bx <> 320 }
jle @l4 { ; then jump to @l4 }
mov bx,1 { ; else BX := 1 (we're on a new line) }
inc si { ; point SI to next element in path }
inc si { ; }
@l4:
dec cx { ; CX-- }
jnz @l2 { ; if CX <> 0 then loop }
end;
for count := 0 to 159 do {set new bottom line}
begin
if random < 0.4 then
delta := random(2)*255;
buffer[101,count] := delta;
buffer[102,count] := delta;
end;
asm
mov si,offset buffer { ; SI := buffer[0] }
mov ax,0A000h { ; AX := 0A000h (vga segment) }
mov es,ax { ; ES := AX }
xor di,di { ; DI := 0 }
mov dx,100 { ; DX := 100 (# of rows div 2) }
@l5:
mov bx,2 { ; BX := 2 }
@l6:
mov cx,160 { ; CX := 160 (# of cols div 2) }
@l7:
mov al,ds:[si] { ; AL := buffer[si] }
mov ah,al { ; AH := AL (replicate byte) }
mov es:[di],ax { ; store two bytes into video memory }
inc di { ; move to next word in VRAM }
inc di { ; }
inc si { ; move to next word in buffer }
inc si { ; }
dec cx { ; CX-- }
jnz @l7 { ; repeat until done with column }
sub si,320 { ; go back to start of line in buffer }
dec bx { ; BX-- }
jnz @l6 { ; repeat until two columns filled }
add si,320 { ; restore position in buffer }
dec dx { ; DX-- }
jnz @l5 { ; repeat until 100 rows filled }
end;
until keypressed;
asm
mov ax,03h { ; AX := 3h }
int 10h { ; restore text mode }
end;
end.
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