Module curlew.io
Functions for performing common IO operations.
Functions
def loadPLY(path)-
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def loadPLY(path): """ Loads a PLY file from the specified path. """ try: from plyfile import PlyData, PlyElement except: assert False, "Please install plyfile (pip install plyfile) to load PLY." data = PlyData.read(path) # load file! # extract data xyz = None rgb = None norm = None faces = None scalar = [] scalar_names = [] for e in data.elements: if 'face' in e.name.lower(): faces = np.vstack( e['vertex_indices']) if 'vert' in e.name.lower(): # vertex data xyz = np.array([e['x'], e['y'], e['z']]).T if len(e.properties) > 3: # vertices have more than just position names = e.data.dtype.names # colour? if 'red' in names and 'green' in names and 'blue' in names: rgb = np.array([e['red'], e['green'], e['blue']], dtype=e['red'].dtype).T # normals? if 'nx' in names and 'ny' in names and 'nz' in names: norm = np.array([e['nx'], e['ny'], e['nz']], dtype=e['nx'].dtype).T # load others as scalar mask = ['red', 'green', 'blue', 'nx', 'ny', 'nz', 'x', 'y', 'z'] for n in names: if not n in mask: scalar_names.append(n) scalar.append(e[n]) elif 'color' in e.name.lower(): # rgb data rgb = np.array([e['r'], e['g'], e['b']], dtype=e['r'].dtype).T elif 'normals' in e.name.lower(): # normal data norm = np.array([e['x'], e['y'], e['z']], dtype=e['z'].dtype).T else: # scalar data scalar_names.append(e.properties[0].name.strip().replace('scalar_','')) scalar.append(np.array(e[e.properties[0].name], dtype=e[e.properties[0].name].dtype)) if len(scalar) > 0: scalar = np.vstack(scalar).T assert (not xyz is None) and (xyz.shape[0] > 0), "Error - PLY contains no geometry?" # TODO - also load faces if present # return everything needed out = dict( xyz = xyz, faces=faces, rgb=rgb, normals=norm, attr=scalar, names=scalar_names ) if len(scalar) == 0: del out['attr'] del out['names'] if rgb is None: del out['rgb'] if norm is None: del out['normals'] if faces is None: del out['faces'] return outLoads a PLY file from the specified path.
def saveOBJ(filename, xyz, rgb, faces)-
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def saveOBJ(filename, xyz, rgb, faces): """ Writes a mesh to an OBJ file. Parameters --------------- filename : str Output file path. xyz : np.ndarray | list List of vertex positions [(x, y, z), ...] rgb: np.ndarray | list List of vertex colors [(r, g, b), ...] or [(r, g, b, a), ...] in [0, 1] or [0, 255] faces: np.ndarray | list List of faces [(i1, i2, i3), ...] with 0-based indices """ with open(filename, 'w') as f: f.write("# OBJ file with vertex colors (stored in comments)\n") for i, v in enumerate(xyz): x, y, z = v color_str = "" if (rgb is not None) and i < len(rgb): color = rgb[i] # Normalize to 0-1 if in 0-255 if max(color) > 1: color = [c / 255.0 for c in color[:3]] else: color = color[:3] color_str = " # color {:.4f} {:.4f} {:.4f}".format(*color) f.write("v {:.6f} {:.6f} {:.6f}{}\n".format(x, y, z, color_str)) for face in faces: # OBJ format is 1-indexed f.write("f {}\n".format(' '.join(str(i + 1) for i in face)))Writes a mesh to an OBJ file.
Parameters
filename:str- Output file path.
xyz:np.ndarray | list- List of vertex positions [(x, y, z), …]
rgb:np.ndarray | list- List of vertex colors [(r, g, b), …] or [(r, g, b, a), …] in [0, 1] or [0, 255]
faces:np.ndarray | list- List of faces [(i1, i2, i3), …] with 0-based indices
def savePLY(path, xyz, rgb=None, normals=None, attr=None, names=None, faces=None)-
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def savePLY(path, xyz, rgb=None, normals=None, attr=None, names=None, faces=None): """ Write a point cloud and associated RGB and scalar fields to .ply. Parameters --------------- Path : str File path for the created (or overwritten) .ply file xyz : np.ndarray Array of xyz points to add to the PLY file rgb : np.ndarray Array of 0-255 RGB values associated with these points, or None. normals : np.ndarray Array of normal vectors associated with each point, or None. attr : np.ndarray Array of float32 values associated with these points, or None attr_names : list List containing names for each of the passed attributes, or None. faces : np.ndarray, optional Array of triangular faces (F x 3) with vertex indices, or None. """ # make directories if need be os.makedirs(os.path.dirname( path ), exist_ok=True ) try: from plyfile import PlyData, PlyElement except: assert False, "Please install plyfile (`pip install plyfile`) to export to PLY." sfmt='f4' # use float32 precision # create structured data arrays and derived PlyElements vertex = np.array(list(zip(xyz[:, 0], xyz[:, 1], xyz[:, 2])), dtype=[('x', 'double'), ('y', 'double'), ('z', 'double')]) ply = [PlyElement.describe(vertex, 'vertices')] # create RGB elements if rgb is not None: if (np.max(rgb) <= 1): irgb = np.clip((rgb * 255),0,255).astype(np.uint8) else: irgb = np.clip(rgb,0,255).astype(np.uint8) # convert to structured arrays and create elements irgb = np.array(list(zip(irgb[:, 0], irgb[:, 1], irgb[:, 2])), dtype=[('r', 'u1'), ('g', 'u1'), ('b', 'u1')]) ply.append(PlyElement.describe(irgb, 'color')) # create ply elements # normal vectors if normals is not None: # convert to structured arrays norm = np.array(list(zip(normals[:, 0], normals[:, 1], normals[:, 2])), dtype=[('x', 'f4'), ('y', 'f4'), ('z', 'f4')]) ply.append(PlyElement.describe(norm, 'normals')) # create ply elements # attributes if attr is not None: if names is None: names = ["SF%d"%(i+1) for i in range(attr.shape[-1])] # map scalar fields to required type and build data arrays data = attr.astype(np.float32) for b in range(data.shape[-1]): n = names[b].strip().replace(' ', '_') #remove spaces from n if 'scalar' in n: #name already includes 'scalar'? ply.append(PlyElement.describe(data[:, b].astype([('%s' % n, sfmt)]), '%s' % n)) else: #otherwise prepend it (so CloudCompare recognises this as a scalar field). ply.append(PlyElement.describe(data[:, b].astype([('scalar_%s' % n, sfmt)]), 'scalar_%s' % n)) # Append faces if present if faces is not None and len(faces) > 0: faces = np.asarray(faces, dtype=np.int32) face_data = np.array( [(list(face),) for face in faces], dtype=[('vertex_indices', 'i4', (3,))] ) ply.append(PlyElement.describe(face_data, 'face')) PlyData(ply).write(path) # and, finally, write everything :-)Write a point cloud and associated RGB and scalar fields to .ply.
Parameters
Path:str- File path for the created (or overwritten) .ply file
xyz:np.ndarray- Array of xyz points to add to the PLY file
rgb:np.ndarray- Array of 0-255 RGB values associated with these points, or None.
normals:np.ndarray- Array of normal vectors associated with each point, or None.
attr:np.ndarray- Array of float32 values associated with these points, or None
attr_names:list- List containing names for each of the passed attributes, or None.
faces:np.ndarray, optional- Array of triangular faces (F x 3) with vertex indices, or None.