meshutils.py

def writeply(X,color,tri,filename):
    """
    Save out a triangulated mesh to a ply file
    
    Parameters
    ----------
    pts3 : 2D numpy.array (dtype=float)
        vertex coordinates shape (3,Nvert)
        
    color : 2D numpy.array (dtype=float)
        vertex colors shape (3,Nvert)
        should be float in range (0..1)
        
    tri : 2D numpy.array (dtype=float)
        triangular faces shape (Ntri,3)
        
    filename : string
        filename to save to    
    """
    f = open(filename,"w");
    f.write('ply\n');
    f.write('format ascii 1.0\n');
    f.write('element vertex %i\n' % X.shape[1]);
    f.write('property float x\n');
    f.write('property float y\n');
    f.write('property float z\n');
    f.write('property uchar red\n');
    f.write('property uchar green\n');
    f.write('property uchar blue\n');
    f.write('element face %d\n' % tri.shape[0]);
    f.write('property list uchar int vertex_indices\n');
    f.write('end_header\n');

    C = (255*color).astype('uint8')
    
    for i in range(X.shape[1]):
        f.write('%f %f %f %i %i %i\n' % (X[0,i],X[1,i],X[2,i],C[0,i],C[1,i],C[2,i]));
    
    for t in range(tri.shape[0]):
        f.write('3 %d %d %d\n' % (tri[t,1],tri[t,0],tri[t,2]))

    f.close();