📄 mandelbrot.cpp
字号:
///////////////////////////////////////////////////////////
// //
// SAGA //
// //
// System for Automated Geoscientific Analyses //
// //
// Module Library: //
// Fractals //
// //
//-------------------------------------------------------//
// //
// Mandelbrot.cpp //
// //
// Copyright (C) 2003 by //
// Olaf Conrad //
// //
//-------------------------------------------------------//
// //
// This file is part of 'SAGA - System for Automated //
// Geoscientific Analyses'. SAGA is free software; you //
// can redistribute it and/or modify it under the terms //
// of the GNU General Public License as published by the //
// Free Software Foundation; version 2 of the License. //
// //
// SAGA 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. See the GNU General Public //
// License for more details. //
// //
// You should have received a copy of the GNU General //
// Public License along with this program; if not, //
// write to the Free Software Foundation, Inc., //
// 59 Temple Place - Suite 330, Boston, MA 02111-1307, //
// USA. //
// //
//-------------------------------------------------------//
// //
// e-mail: oconrad@saga-gis.org //
// //
// contact: Olaf Conrad //
// Institute of Geography //
// University of Goettingen //
// Goldschmidtstr. 5 //
// 37077 Goettingen //
// Germany //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
#include "Mandelbrot.h"
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
CMandelbrot::CMandelbrot(void)
{
//-----------------------------------------------------
// 1. Info...
Set_Name(_TL("Mandelbrot Set"));
Set_Author(_TL("Copyrights (c) 2001 by Olaf Conrad"));
Set_Description (_TW(
"Calculates Mandelbrot and Julia sets.\n\n"
"References:\n"
"- Mandelbrot, B.B. (1983): 'The Fractal Geometry of Nature', New York, 490p.\n")
);
//-----------------------------------------------------
// 2. Grids...
Parameters.Add_Grid_Output(
NULL , "GRID" , _TL("Grid"),
_TL("")
);
Parameters.Add_Value(
NULL , "NX" , _TL("Width (Cells)"),
_TL(""),
PARAMETER_TYPE_Int, 100, 1, true
);
Parameters.Add_Value(
NULL , "NY" , _TL("Height (Cells)"),
_TL(""), PARAMETER_TYPE_Int, 100, 1, true
);
Parameters.Add_Range(
NULL , "XRANGE" , _TL("X-Range"),
_TL(""), -2.0, 1.0
);
Parameters.Add_Range(
NULL , "YRANGE" , _TL("Y-Range"),
_TL(""),
-1.5, 1.5
);
Parameters.Add_Value(
NULL , "JULIA_X" , _TL("Julia - X"),
_TL(""), PARAMETER_TYPE_Double, -0.7
);
Parameters.Add_Value(
NULL , "JULIA_Y" , _TL("Julia - Y"),
_TL(""), PARAMETER_TYPE_Double, 0.3
);
Parameters.Add_Value(
NULL , "MAXITER" , _TL("Maximum Iterations"),
_TL(""),
PARAMETER_TYPE_Int, 300, 1, true
);
Parameters.Add_Choice(
NULL , "METHOD" , _TL("Fractal Type"),
_TL(""),
CSG_String::Format(SG_T("%s|%s|"),
_TL("Mandelbrot"),
_TL("Julia")
), 0
);
}
//---------------------------------------------------------
CMandelbrot::~CMandelbrot(void)
{}
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
bool CMandelbrot::On_Execute(void)
{
//-----------------------------------------------------
m_Extent.Assign(
Parameters("XRANGE")->asRange()->Get_LoVal(),
Parameters("YRANGE")->asRange()->Get_LoVal(),
Parameters("XRANGE")->asRange()->Get_HiVal(),
Parameters("YRANGE")->asRange()->Get_HiVal()
);
m_maxIterations = Parameters("MAXITER") ->asInt();
m_maxDistance = 4.0;
m_Method = Parameters("METHOD") ->asInt();
m_xJulia = Parameters("JULIA_X") ->asDouble();
m_yJulia = Parameters("JULIA_Y") ->asDouble();
m_pGrid = SG_Create_Grid(GRID_TYPE_Int, Parameters("NX")->asInt(), Parameters("NY")->asInt());
m_pGrid->Set_Name(m_Method == 0 ? _TL("Mandelbrot Set") : _TL("Julia Set"));
Parameters("GRID")->Set_Value(m_pGrid);
//-----------------------------------------------------
Calculate();
//-----------------------------------------------------
return( true );
}
//---------------------------------------------------------
#define GET_POS(p) p.Assign(\
m_Extent.Get_XMin() + m_Extent.Get_XRange() * (ptWorld.Get_X() - m_pGrid->Get_XMin()) / m_pGrid->Get_XRange(),\
m_Extent.Get_YMin() + m_Extent.Get_YRange() * (ptWorld.Get_Y() - m_pGrid->Get_YMin()) / m_pGrid->Get_YRange());
#define SET_POS(a, b) if( a.Get_X() > b.Get_X() ) { d = a.m_point.x; a.m_point.x = b.m_point.x; b.m_point.x = d; }\
if( a.Get_Y() > b.Get_Y() ) { d = a.m_point.y; a.m_point.y = b.m_point.y; b.m_point.y = d; }
//---------------------------------------------------------
bool CMandelbrot::On_Execute_Position(CSG_Point ptWorld, TSG_Module_Interactive_Mode Mode)
{
double d;
switch( Mode )
{
default:
break;
case MODULE_INTERACTIVE_LDOWN:
case MODULE_INTERACTIVE_RDOWN:
GET_POS(m_Down);
return( true );
case MODULE_INTERACTIVE_LUP:
GET_POS(m_Up);
SET_POS(m_Up, m_Down);
if( m_Up.Get_X() >= m_Down.Get_X() || m_Up.Get_Y() >= m_Down.Get_Y() )
{
m_Extent.Inflate(50.0);
m_Extent.Move(m_Up - m_Extent.Get_Center());
}
else
{
m_Extent.Assign(m_Up, m_Down);
}
Calculate();
return( true );
case MODULE_INTERACTIVE_RUP:
GET_POS(m_Up);
SET_POS(m_Up, m_Down);
if( m_Up.Get_X() >= m_Down.Get_X() || m_Up.Get_Y() >= m_Down.Get_Y() )
{
m_Extent.Deflate(50.0);
m_Extent.Move(m_Up - m_Extent.Get_Center());
}
else
{
m_Extent.Deflate(100.0 * (m_Down.Get_X() - m_Up.Get_X()) / m_Extent.Get_XRange());
m_Extent.Move(m_Up - m_Extent.Get_Center());
}
Calculate();
return( true );
}
return( false );
}
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
void CMandelbrot::Calculate(void)
{
int x, y, i;
double xPos, yPos, dx, dy;
dx = m_Extent.Get_XRange() / (m_pGrid->Get_NX() - 1.0);
dy = m_Extent.Get_YRange() / (m_pGrid->Get_NY() - 1.0);
for(y=0, yPos=m_Extent.Get_YMin(); y<m_pGrid->Get_NY() && Set_Progress(y, m_pGrid->Get_NY()); y++, yPos+=dy)
{
for(x=0, xPos=m_Extent.Get_XMin(); x<m_pGrid->Get_NX(); x++, xPos+=dx)
{
switch( m_Method )
{
default:
case 0: i = Get_Mandelbrot (xPos, yPos); break;
case 1: i = Get_Julia (xPos, yPos); break;
}
if( i >= m_maxIterations )
{
m_pGrid->Set_NoData(x, y);
}
else
{
m_pGrid->Set_Value(x, y, i);
}
}
}
DataObject_Update(m_pGrid, true);
}
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
int CMandelbrot::Get_Mandelbrot(double xPos, double yPos)
{
int i;
double x, y, k;
for(i=0, x=0.0, y=0.0; i<m_maxIterations; i++)
{
k = xPos + x*x - y*y;
y = yPos + 2.0 * x * y;
x = k;
if( m_maxDistance < x*x + y*y )
{
return( i );
}
}
return( i );
}
//---------------------------------------------------------
int CMandelbrot::Get_Julia(double xPos, double yPos)
{
int i;
double x, y, k;
for(i=0, x=xPos, y=yPos; i<m_maxIterations; i++)
{
k = m_xJulia + x*x - y*y;
y = m_yJulia + 2.0 * x * y;
x = k;
if( m_maxDistance < x*x + y*y )
{
return( i );
}
}
return( i );
}
///////////////////////////////////////////////////////////
// //
// //
// //
///////////////////////////////////////////////////////////
//---------------------------------------------------------
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -