c++ - Having problems with my OpenGL plane -

i'm having bit of trouble creating plane (using gl_triangle) using vertex arrays.

heres code:

float halfw = (getplanewidth() / 2); float halfd = (getplanedepth() / 2);  //generate vertices for(int z = halfd; z >= -halfd; z--) {     for(int x = -halfw; x <= halfw; x++)     {         float xv = x * cellwidth;         float yv = 0;         float zv = z * celldepth;          vertices.push_back(xv);         vertices.push_back(yv);         vertices.push_back(zv);          float xn = xv - getx();         float yn = yv - gety();         float zn = zv - getz();          setnormals(&xn, &yn, &zn); //calculate normals         normals.push_back(xn);         normals.push_back(yn);         normals.push_back(zn);     } } //generate indices for(int y = 0; y < getplanedepth(); y++) {     for(int x = 0; x < getplanewidth(); x++)     {         int curvertex = (x + (y * (getplanedepth() + 1))); //bottom left vertex id          if(curvertex%2 == 0)         {             indices.push_back((x)    + (y)   * (getplanedepth()+1)); //bottom left             indices.push_back((x+1)  + (y)   * (getplanedepth()+1)); //bottom right             indices.push_back((x+1)  + (y+1) * (getplanedepth()+1)); //top right              indices.push_back((x+1)  + (y+1) * (getplanedepth()+1)); //top right             indices.push_back((x)    + (y+1) * (getplanedepth()+1)); //top left             indices.push_back((x)    + (y)   * (getplanedepth()+1)); //bottom left         }         else //reverse triangle         {             indices.push_back((x+1)  + (y)   * (getplanedepth()+1)); //bottom right             indices.push_back((x)    + (y)   * (getplanedepth()+1)); //bottom left             indices.push_back((x)    + (y+1) * (getplanedepth()+1)); //top left              indices.push_back((x)    + (y+1) * (getplanedepth()+1)); //top left             indices.push_back((x+1)  + (y+1) * (getplanedepth()+1)); //top right             indices.push_back((x+1)  + (y)   * (getplanedepth()+1)); //bottom right         }     } } 

the code works fine if width , depth same, if different, screws up.

can see problem?

i've coded pivot point in middle of plane.

    int curvertex = (x + (y * (getplanewidth() + 1))); //bottom left vertex id      if(curvertex%2 == 0)     {         indices.push_back((x)    + (y)   * (getplanewidth()+1)); //bottom left         indices.push_back((x+1)  + (y)   * (getplanewidth()+1)); //bottom right         indices.push_back((x+1)  + (y+1) * (getplanewidth()+1)); //top right          indices.push_back((x+1)  + (y+1) * (getplanewidth()+1)); //top right         indices.push_back((x)    + (y+1) * (getplanewidth()+1)); //top left         indices.push_back((x)    + (y)   * (getplanewidth()+1)); //bottom left     }     else //reverse triangle     {         indices.push_back((x+1)  + (y)   * (getplanewidth()+1)); //bottom right         indices.push_back((x)    + (y)   * (getplanewidth()+1)); //bottom left         indices.push_back((x)    + (y+1) * (getplanewidth()+1)); //top left          indices.push_back((x)    + (y+1) * (getplanewidth()+1)); //top left         indices.push_back((x+1)  + (y+1) * (getplanewidth()+1)); //top right         indices.push_back((x+1)  + (y)   * (getplanewidth()+1)); //bottom right     } 

?