1 files changed, 101 insertions, 0 deletions
diff --git a/particles.cpp b/particles.cpp
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+++ b/particles.cpp
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+//
+//  glgrav - OpenGL N-Body gravity simulator
+//
+//  Copyright (C) 2003  Ian Cowburn (ianc@noddybox.demon.co.uk)
+//
+//  This program 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; either version 2 of the License, or
+//  (at your option) any later version.
+//
+//  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.  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
+//
+//  -------------------------------------------------------------------------
+//
+//  Particles
+//
+//
+static const char id[]="$Id$";
+
+#include "particles.h"
+
+Particles::Particles(GLfloat alpha_dec, GLfloat alpha_min)
+{
+    m_alpha_dec=alpha_dec;
+    m_alpha_min=alpha_min;
+}
+
+
+Particles::~Particles()
+{
+}
+
+
+void Particles::add(GLfloat x1, GLfloat y1, GLfloat z1,
+		    GLfloat x2, GLfloat y2, GLfloat z2,
+		    GLfloat r, GLfloat g, GLfloat b)
+{
+    Point p;
+
+    p.x1=x1;
+    p.y1=y1;
+    p.z1=z1;
+    p.x2=x2;
+    p.y2=y2;
+    p.z2=z2;
+    p.r=r;
+    p.g=g;
+    p.b=b;
+    p.a=1.0;
+
+    m_list.push_back(p);
+}
+
+
+void Particles::draw()
+{
+    list<Point>::iterator i;
+
+    glBegin(GL_LINES);
+
+    for(i=m_list.begin();i!=m_list.end();i++)
+	{
+	i->a-=m_alpha_dec;
+
+	glColor4f(i->r,i->g,i->b,i->a);
+	glVertex3f(i->x1,i->y1,i->z1);
+	glVertex3f(i->x2,i->y2,i->z2);
+	}
+
+    glEnd();
+}
+
+
+void Particles::update()
+{
+    list<Point>::iterator i;
+
+    // Delete dead particles
+    //
+    i=m_list.begin();
+    
+    while ((i!=m_list.end())&&(i->a<=m_alpha_min))
+    	{
+	m_list.pop_front();
+	i=m_list.begin();
+	}
+
+    // Update them
+    //
+    for(i=m_list.begin();i!=m_list.end();i++)
+	i->a-=m_alpha_dec;
+}
+
+// END OF FILE //