fpc/install/demo/mandel.pp
2000-01-04 15:29:42 +00:00

346 lines
9.4 KiB
ObjectPascal

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 1993-98 by Gernot Tenchio
Mandelbrot Example using the Graph unit
See the file COPYING.FPC, included in this distribution,
for details about the copyright.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
**********************************************************************}
program mandel;
{
Mandelbrot example using the graph unit.
Note: For linux you need to run this program as root !!
}
uses
{$ifdef go32v2}
dpmiexcp,
{$endif go32v2}
dos,Graph;
const
shift:byte=12;
var
SearchPoint,ActualPoint,NextPoint : PointType;
LastColor : longint;
Gd,Gm,
Max_Color,Max_X_Width,
Max_Y_Width,Y_Width : word;
Y1,Y2,X1,X2,Dy,Dx : Real;
Zm : Integer;
SymetricCase : boolean;
LineY : array [0..600] OF BYTE;
LineX : array [0..100,0..600] OF INTEGER;
const
SX : array [0..7] OF SHORTINT=(-1, 0, 1, 1, 1, 0,-1,-1);
SY : array [0..7] OF SHORTINT=(-1,-1,-1, 0, 1, 1, 1, 0);
type
arrayType = array[1..50] of integer;
{------------------------------------------------------------------------------}
function ColorsEqual(c1, c2 : longint) : boolean;
begin
ColorsEqual:=((GetMaxColor=$FF) and ((c1 and $FF)=(c2 and $FF))) or
((GetMaxColor=$7FFF) and ((c1 and $F8F8F8)=(c2 and $F8F8F8))) or
((GetMaxColor=$FFFF) and ((c1 and $F8FCF8)=(c2 and $F8FCF8))) or
((GetMaxColor>$10000) and ((c1 and $FFFFFF)=(c2 and $FFFFFF)));
end;
{------------------------------------------------------------------------------}
function CalcMandel(Point:PointType; z:integer) : Longint ;
var
x,y,xq,yq,Cx,Cy : real ;
begin
Cy:=y2 + dy*Point.y ;
Cx:=x2 + dx*Point.x ;
X:=-Cx ; Y:=-Cy ;
repeat
xq:=x * x;
yq:=y * y ;
y :=x * y;
y :=y + y - cy;
x :=xq - yq - cx ;
z :=z -1;
until (Z=0) or (Xq + Yq > 4 );
if Z=0 Then
CalcMandel:=(blue and $FFFFFF)
else
CalcMandel:=(z mod Max_Color) + 1 ;
end;
{-----------------------------------------------------------------------------}
procedure Partition(var A : arrayType; First, Last : Byte);
var
Right,Left : byte ;
V,Temp : integer;
begin
V := A[(First + Last) SHR 1];
Right := First;
Left := Last;
repeat
while (A[Right] < V) do
inc(Right);
while (A[Left] > V) do
Dec(Left);
if (Right <= Left) then
begin
Temp:=A[Left];
A[Left]:=A[Right];
A[Right]:=Temp;
Right:=Right+1;
Left:=Left-1;
end;
until Right > Left;
if (First < Left) then
Partition(A, First, Left);
if (Right < Last) then
Partition(A, Right, Last)
end;
{-----------------------------------------------------------------------------}
function BlackScan(var NextPoint:PointType) : boolean;
begin
BlackScan:=true;
repeat
if NextPoint.X=Max_X_Width then
begin
if NextPoint.Y < Y_Width then
begin
NextPoint.X:=0 ;
NextPoint.Y:=NextPoint.Y+1;
end
else
begin
BlackScan:=false;
exit;
end ; { IF }
end ; { IF }
NextPoint.X:=NextPoint.X+1;
until GetPixel(NextPoint.X,NextPoint.Y)=0;
end ;
{------------------------------------------------------------------------------}
procedure Fill(Ymin,Ymax,LastColor:integer);
var
P1,P3,P4,P : integer ;
Len,P2 : byte ;
Darray : arraytype;
begin
SetColor(LastColor);
for P1:=Ymin+1 to Ymax-1 do
begin
Len:=LineY[P1] ;
if Len >= 2 then
begin
for P2:=1 to Len do
Darray[P2]:=LineX[P2,P1] ;
if Len > 2 then
Partition(Darray,1,len);
P2:=1;
repeat
P3:= Darray[P2] ; P4:= Darray[P2 + 1];
if P3 <> P4 then
begin
line ( P3 , P1 , P4 , P1) ;
if SymetricCase then
begin
P:=Max_Y_Width-P1;
line ( P3 , P , P4 , P ) ;
end;
end; { IF }
P2:=P2+2;
until P2 >= Len ;
end; { IF }
end; { FOR }
end;
{-----------------------------------------------------------------------------}
Function NewPosition(Last:Byte):Byte;
begin
newposition:=(((last+1) and 254)+6) and 7;
end;
{-----------------------------------------------------------------------------}
procedure CalcBounds;
var
lastOperation,KK,
Position : Byte ;
foundcolor : longint;
Start,Found,NotFound : boolean ;
MerkY,Ymax : Integer ;
label
L;
begin
repeat
FillChar(LineY,SizeOf(LineY),0) ;
ActualPoint:=NextPoint;
LastColor:=CalcMandel(NextPoint,Zm) ;
putpixel (ActualPoint.X,ActualPoint.Y,LastColor);
if SymetricCase then
putpixel (ActualPoint.X,Max_Y_Width-ActualPoint.Y,LastColor) ;
Ymax:=NextPoint.Y ;
MerkY:=NextPoint.Y ;
NotFound:=false ;
Start:=false ;
LastOperation:=4 ;
repeat
Found:=false ;
KK:=0 ;
Position:=NewPosition(LastOperation);
repeat
LastOperation:=(Position+KK) and 7 ;
SearchPoint.X:=ActualPoint.X+Sx[LastOperation];
SearchPoint.Y:=ActualPoint.Y+Sy[LastOperation];
if ((SearchPoint.X < 0) or
(SearchPoint.X > Max_X_Width) or
(SearchPoint.Y < NextPoint.Y) or
(SearchPoint.Y > Y_Width)) then
goto L;
if (SearchPoint.X=NextPoint.X) and (SearchPoint.Y=NextPoint.Y) then
begin
Start:=true ;
Found:=true ;
end
else
begin
FoundColor:=GetPixel(SearchPoint.X,SearchPoint.Y) ;
if FoundColor = 0 then
begin
FoundColor:= CalcMandel (SearchPoint,Zm) ;
Putpixel (SearchPoint.X,SearchPoint.Y,FoundColor) ;
if SymetricCase then
PutPixel (SearchPoint.X,Max_Y_Width-SearchPoint.Y,FoundColor) ;
end ;
if ColorsEqual(FoundColor,LastColor) then
begin
if ActualPoint.Y <> SearchPoint.Y then
begin
if SearchPoint.Y = MerkY then
LineY[ActualPoint.Y]:=LineY[ActualPoint.Y]-1;
MerkY:= ActualPoint.Y ;
LineY[SearchPoint.Y]:=LineY[SearchPoint.Y]+1;
end ;
LineX[LineY[SearchPoint.Y],SearchPoint.Y]:=SearchPoint.X ;
if SearchPoint.Y > Ymax then Ymax:= SearchPoint.Y ;
Found:=true ;
ActualPoint:=SearchPoint ;
end;
L:
KK:=KK+1;
if KK > 8 then
begin
Start:=true ;
NotFound:=true ;
end;
end;
until Found or (KK > 8);
until Start ;
if not NotFound then
Fill(NextPoint.Y,Ymax,LastColor) ;
until not BlackScan(NextPoint);
end ;
{------------------------------------------------------------------------------
MAINROUTINE
------------------------------------------------------------------------------}
var
error : word;
var neededtime,starttime : longint;
hour, minute, second, sec100 : word;
const
{$ifdef win32}
gmdefault : word = m640x480x16;
{$else not win32}
{$ifdef Linux}
gmdefault : word = g640x480x256;
{$else}
gmdefault : word = m640x480x256;
{$endif}
{$endif win32}
begin
if paramcount>0 then
begin
val(paramstr(1),gm,error);
if error<>0 then
gm:=gmdefault;
end
else
gm:=gmdefault;
gd:=detect;
GetTime(hour, minute, second, sec100);
starttime:=((hour*60+minute)*60+second)*100+sec100;
InitGraph(gd,gm,'');
if GraphResult <> grOk then
begin
Writeln('Graph driver ',gd,' graph mode ',gm,' not supported');
Halt(1);
end;
Max_X_Width:=GetMaxX;
Max_y_Width:=GetMaxY;
Max_Color:=GetMaxColor-1;
ClearViewPort;
x1:=-0.9;
x2:= 2.2;
y1:= 1.25;
y2:=-1.25;
zm:=90;
dx:=(x1 - x2) / Max_X_Width ;
dy:=(y1 - y2) / Max_Y_Width ;
if abs(y1) = abs(y2) then
begin
SymetricCase:=true;
Y_Width:=Max_Y_Width shr 1
end
else
begin
SymetricCase:=false;
Y_Width:=Max_Y_Width;
end;
NextPoint.X:=0;
NextPoint.Y:=0;
LastColor:=CalcMandel(SearchPoint,zm);
CalcBounds ;
GetTime(hour, minute, second, sec100);
neededtime:=((hour*60+minute)*60+second)*100+sec100-starttime;
{$ifndef fpc_profile}
readln;
{$endif fpc_profile}
CloseGraph;
Writeln('Mandel took ',neededtime/100:0:3,' secs to generate mandel graph');
Writeln('With graph driver ',gd,' and graph mode ',gm);
end.
{
$Log$
Revision 1.8 2000-01-04 15:29:42 marco
* fixed constants for graphmodes
Revision 1.7 1999/12/22 14:36:07 jonas
* changed type of max_color to word so it works now with 16bit color modes
(thanks to Arjan van Dijk for noticing the problem)
Revision 1.6 1999/12/14 22:59:52 pierre
* adapted to new graph unit
Revision 1.5 1999/05/27 21:36:33 peter
* new demo's
* fixed mandel for linux
Revision 1.4 1998/12/20 22:22:10 peter
* updates
}