raytree.cpp

#include <cstdio>
#include <cstdlib>

// Included files for OpenGL Rendering
#ifdef __APPLE__
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#else
#include <GL/gl.h>
#include <GL/glu.h>
#endif

#include "raytree.h"

// ====================================================================
// Initialize the static variables
int RayTree::activated = 0;  
std::vector<Segment> RayTree::main_segments;
std::vector<Segment> RayTree::shadow_segments;
std::vector<Segment> RayTree::reflected_segments;

// ====================================================================

void Segment::paint() {
  glVertex3f(a.x(),a.y(),a.z());
  glVertex3f(b.x(),b.y(),b.z());
}

// ====================================================================

void RayTree::paintHelper(const Vec4f &m,const Vec4f &s,const Vec4f &r,const Vec4f &t) {
  glBegin(GL_LINES);
  unsigned int i;
  glColor4f(m.r(),m.g(),m.b(),m.a());
  for (i = 0; i < main_segments.size(); i++) {
    main_segments[i].paint(); }
  glColor4f(s.r(),s.g(),s.b(),s.a());
  for (i = 0; i < shadow_segments.size(); i++) {
    shadow_segments[i].paint(); }
  glColor4f(r.r(),r.g(),r.b(),r.a());
  for (i = 0; i < reflected_segments.size(); i++) {
    reflected_segments[i].paint(); }
  glColor4f(t.r(),t.g(),t.b(),t.a());
  glEnd();
}

// ====================================================================

void RayTree::paint() {
  glLineWidth(2);
  glDisable(GL_LIGHTING);

  // this allows you to see rays passing through objects
  // turn off the depth test and blend with the current pixel color
  glDisable(GL_DEPTH_TEST);
  glEnable(GL_BLEND);
  glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
  paintHelper(Vec4f(0.7,0.7,0.7,0.3),
	      Vec4f(0.1,0.9,0.1,0.3),
	      Vec4f(0.9,0.1,0.1,0.3),
	      Vec4f(0.1,0.1,0.9,0.3));
  glDisable(GL_BLEND);
  glEnable(GL_DEPTH_TEST);

  // with the depth test enabled, draw the lines solid
  paintHelper(Vec4f(0.7,0.7,0.7,1.0),
	      Vec4f(0.1,0.9,0.1,1.0),
	      Vec4f(0.9,0.1,0.1,1.0),
	      Vec4f(0.1,0.1,0.9,1.0));
	      
  glEnable(GL_LIGHTING);
}

// ====================================================================