Source code for paraview.algorithms.savgreader

"""Reader for NIST SAVG files.

This reader reads in a .savg file and produces a vtkPartionedDatasSetCollection
with one vtkPartitionedDataSet for each type of primitive: points, lines,
and polygons.


from paraview.util.vtkAlgorithm import VTKPythonAlgorithmBase

from .. import print_error

[docs]def get_coords_from_line(line): """ Given a line, split it, and parse out the coordinates. Return: A tuple containing coords (position, color, normal) """ values = line.split() pt = None pt_n = None pt_col = None # The first three are always the point coords if len(values) >= 3: pt = [float(values[0]), float(values[1]), float(values[2])] # Then if there are only 6 total, the next three are normal coords if len(values) == 6: pt_n = [float(values[3]), float(values[4]), float(values[5])] else: if len(values) >= 7: # Otherwise the next 4 are colors pt_col = [float(values[3]), float(values[4]), float(values[5]), float(values[6])] if len(values) >= 10: # And if there are more, those are the normals pt_n = [float(values[7]), float(values[8]), float(values[9])] return pt, pt_col, pt_n
[docs]def not_supported(line): return ( line.startswith('tri') or line.startswith('pixel') or line.startswith('text') or line.startswith('program') or line.startswith('attribute') or line.startswith('nooptimizations') )
[docs]class SAVGReader(VTKPythonAlgorithmBase): def __init__(self): VTKPythonAlgorithmBase.__init__(self, nInputPorts=0, nOutputPorts=1, outputType="vtkPartitionedDataSetCollection") self._filename = None self._ndata = None self._timesteps = None
[docs] def SetFileName(self, name): """Specify filename for the file to read.""" if name.lower().endswith("savg"): if self._filename != name: self._filename = name self.Modified()
[docs] def RequestData(self, request, inInfoVec, outInfoVec): from vtkmodules.vtkCommonCore import vtkFloatArray, vtkPoints from vtkmodules.vtkCommonDataModel import ( vtkCellArray, vtkCompositeDataSet, vtkPartitionedDataSet, vtkPartitionedDataSetCollection, vtkPolyData ) output = vtkPartitionedDataSetCollection.GetData(outInfoVec); partitioned_datasets = [] partitioned_dataset_names = [] # Parse line file if not self._filename: print_error("SAVGReader requires a FileName") return 0 # Stores lines of text from the file associated with each group of # geometries encountered. geometries = { "lines": [], "points": [], "poly": [] } # Read the file and build up data structure to hold the primitives with open(self._filename, "r") as file: current = None for line in file: parts = line.split("#") line = parts[0].strip().lower() if len(line) < 1: continue if not_supported(line): continue if line.startswith("lin"): geometries["lines"].append({ "rgba": None, "values": [] }) current = geometries["lines"][-1] line_parts = line.split(" ") if len(line_parts) == 5: current["rgba"] = [float(n) for n in line_parts[1:]] elif line.startswith("point"): geometries["points"].append({ "rgba": None, "values": [], }) current = geometries["points"][-1] line_parts = line.split(" ") if len(line_parts) == 5: current["rgba"] = [float(n) for n in line_parts[1:]] elif line.startswith("poly"): geometries["poly"].append({ "rgba": None, "npts": None, "values": [], }) current = geometries["poly"][-1] line_parts = line.split(" ") if len(line_parts) == 2: current["npts"] = int(line_parts[1]) elif len(line_parts) == 6: current["rgba"] = [float(n) for n in line_parts[1:5]] current["npts"] = int(line_parts[5]) elif line.startswith("end"): current = None else: if current is not None: if "npts" in current and current["npts"] is not None: # polygon, known num pts per poly if len(current["values"]) == current["npts"]: # Reached the number of points for the current one, # start a new one. geometries["poly"].append({ "npts": current["npts"], "rgba": current["rgba"], "values": [] }) current = geometries["poly"][-1] pt, pt_col, pt_n = get_coords_from_line(line) if pt: current["values"].append({ "pos": pt, }) color = pt_col or current["rgba"] if color: current["values"][-1]["col"] = color if pt_n: current["values"][-1]["norm"] = pt_n # Build lines polydata if there were any lines if geometries["lines"]: line_points = vtkPoints() line_cells = vtkCellArray() line_point_colors = vtkFloatArray() line_point_colors.SetNumberOfComponents(4) line_point_colors.SetName("rgba_colors") line_point_normals = vtkFloatArray() line_point_normals.SetNumberOfComponents(3) line_point_normals.SetName("vertex_normals") pt_count = 0 for batch in geometries["lines"]: num_in_batch = len(batch["values"]) first_in_batch = True for coord in batch["values"]: if "pos" in coord: line_points.InsertNextPoint(coord["pos"]) if "norm" in coord: line_point_normals.InsertNextTuple(coord["norm"]) if "col" in coord: line_point_colors.InsertNextTuple(coord["col"]) if first_in_batch: line_cells.InsertNextCell(num_in_batch) first_in_batch = False line_cells.InsertCellPoint(pt_count) pt_count += 1 output_lines = vtkPolyData() output_lines.SetPoints(line_points) output_lines.SetLines(line_cells) if line_point_colors.GetNumberOfTuples() > 0: output_lines.GetPointData().AddArray(line_point_colors) if line_point_normals.GetNumberOfTuples() > 0: output_lines.GetPointData().AddArray(line_point_normals) ds = vtkPartitionedDataSet() ds.SetNumberOfPartitions(1) ds.SetPartition(0, output_lines) partitioned_datasets.append(ds) partitioned_dataset_names.append("Lines") # Build the points polydata if we found points if geometries["points"]: p_points = vtkPoints() p_cells = vtkCellArray() p_point_colors = vtkFloatArray() p_point_colors.SetNumberOfComponents(4) p_point_colors.SetName("rgba_colors") p_point_normals = vtkFloatArray() p_point_normals.SetNumberOfComponents(3) p_point_normals.SetName("vertex_normals") p_count = 0 for batch in geometries["points"]: num_in_batch = len(batch["values"]) first_in_batch = True for coord in batch["values"]: if "pos" in coord: p_points.InsertNextPoint(coord["pos"]) if "norm" in coord: p_point_normals.InsertNextTuple(coord["norm"]) if "col" in coord: p_point_colors.InsertNextTuple(coord["col"]) if first_in_batch: p_cells.InsertNextCell(num_in_batch) first_in_batch = False p_cells.InsertCellPoint(p_count) p_count += 1 output_points = vtkPolyData() output_points.SetPoints(p_points) output_points.SetVerts(p_cells) if p_point_colors.GetNumberOfTuples() > 0: output_points.GetPointData().AddArray(p_point_colors) if p_point_normals.GetNumberOfTuples() > 0: output_points.GetPointData().AddArray(p_point_normals) ds = vtkPartitionedDataSet() ds.SetNumberOfPartitions(1) ds.SetPartition(0, output_points) partitioned_datasets.append(ds) partitioned_dataset_names.append("Points") # Build the polygons if there were any if geometries["poly"]: poly_points = vtkPoints() poly_cells = vtkCellArray() poly_point_colors = vtkFloatArray() poly_point_colors.SetNumberOfComponents(4) poly_point_colors.SetName("rgba_colors") poly_point_normals = vtkFloatArray() poly_point_normals.SetNumberOfComponents(3) poly_point_normals.SetName("vertex_normals") pt_count = 0 for batch in geometries["poly"]: num_in_batch = len(batch["values"]) if num_in_batch < 1: continue first_in_batch = True for coord in batch["values"]: if "pos" in coord: poly_points.InsertNextPoint(coord["pos"]) if "norm" in coord: poly_point_normals.InsertNextTuple(coord["norm"]) if "col" in coord: poly_point_colors.InsertNextTuple(coord["col"]) if first_in_batch: np_in_cell = num_in_batch poly_cells.InsertNextCell(np_in_cell) first_in_batch = False poly_cells.InsertCellPoint(pt_count) pt_count += 1 output_polys = vtkPolyData() output_polys.SetPoints(poly_points) output_polys.SetPolys(poly_cells) if poly_point_colors.GetNumberOfTuples() > 0: output_polys.GetPointData().AddArray(poly_point_colors) if poly_point_normals.GetNumberOfTuples() > 0: output_polys.GetPointData().AddArray(poly_point_normals) ds = vtkPartitionedDataSet() ds.SetNumberOfPartitions(1) ds.SetPartition(0, output_polys) partitioned_datasets.append(ds) partitioned_dataset_names.append("Polygons") # Add any partioned datasets we created output.SetNumberOfPartitionedDataSets(len(partitioned_datasets)) for idx, pds in enumerate(partitioned_datasets): output.SetPartitionedDataSet(idx, pds) output.GetMetaData(idx).Set(vtkCompositeDataSet.NAME(), partitioned_dataset_names[idx]) return 1