function appendCube (x, y, z, size) {
      var halfSize = size * 0.5;
      appendBox(x - halfSize, y - halfSize, z - halfSize,
                x + halfSize, y + halfSize, z + halfSize);
    }
// Appends a cube with the given centerpoint and size.
Appends a cube with the given centerpoint and size.
Appends a cube with the given centerpoint and size .
function appendCube (x, y, z, size) {
      var halfSize = size * 0.5;
      appendBox(x - halfSize, y - halfSize, z - halfSize,
                x + halfSize, y + halfSize, z + halfSize);
    }
function appendCube ( x , y , z , size ) { var halfSize = size * 0.5 ; appendBox ( x - halfSize , y - halfSize , z - halfSize , x + halfSize , y + halfSize , z + halfSize ) ; }
Appends a cube with the given centerpoint and size.
Appends a cube with the given centerpoint and size .