grid.cpp

#include "grid.h"

using namespace std; 

Grid::Grid(unsigned int size,float minval,float maxval) {
  const float w = maxval-minval;
  const float h = w;

  const float stepW  = w/(float)size;
  const float stepH  = h/(float)size;
  const float startx = minval;
  const float starty = minval;

  for(unsigned int i=0;i<size;++i) {
    for(unsigned int j=0;j<size;++j) {
      
      const float currentx = startx+stepW*(float)j;
      const float currenty = starty+stepH*(float)i;
     
      _vertices.push_back(currentx);
      _vertices.push_back(currenty);
      _vertices.push_back(0.0f);

      if(i>0 && j>0) {
	int i1 = i*size+j;
	int i2 = (i-1)*size+j;
	int i3 = (i-1)*size+j-1;
	int i4 = i*size+j-1;
	
	_faces.push_back(i1);
	_faces.push_back(i2);
	_faces.push_back(i3);
	_faces.push_back(i3);
	_faces.push_back(i4);
	_faces.push_back(i1);
      }
    }
  }

  _nbVertices = _vertices.size()/3;
  _nbFaces    = _faces.size()/3;
}

Grid::~Grid() {
  _vertices.clear();
  _faces.clear();
}