Script for separating a STEP CAD file into different volumes using Cubit/Trelis

create_parts.py

                                                                                                                                                   
import cubit                                                                                                                                       
import argparse                                                                                                                                    
                                                                                                                                                   
                                                                                                                                                   
# dictionary containing the appropriate                                                                                                            
# (export_type, file_extension)                                                                                                                    
# for each allowed export type in the script                                                                                                       
EXPORT_TYPES = {                                                                                                                                   
    "stl" : ("stl", ".stl"),                                                                                                                       
    "sat" : ("acis", ".sat"),                                                                                                                      
    "acis" : ("acis", ".sat")                                                                                                                      
                                                                                                                                                   
    }                                                                                                                                              
                                                                                                                                                   
                                                                                                                                                   
def parse_filename(input_file):                                                                                                                    
                                                                                                                                                   
    elements = input_file.split("/")                                                                                                               
    # if this is not a relative/absolute path                                                                                                      
    # then assume current directory                                                                                                                
    if elements[0] == input_file:                                                                                                                  
        directory = "./"                                                                                                                           
    else:                                                                                                                                          
        directory = "/".join(elements[:-1]) + "/"                                                                                                  
                                                                                                                                                   
    basename = elements[-1][:-5]                                                                                                                   
                                                                                                                                                   
    return directory, basename                                                                                                                     
                                                                                                                                                   
def main(input_file, export_type, output_dir, dry_run = False):                                                                                    
                                                                                                                                                   
    # sort out where we're goint to put                                                                                                            
    # the volume files                                                                                                                             
    out_dir, basename = parse_filename(input_file)                                                                                                 
    if (len(output_dir)):                                                                                                                          
        out_dir = output_dir                                                                                                                       
                                                                                                                                                   
    if out_dir[-1] != "/":                                                                                                                         
        out_dir += "/"                                                                                                                             
                                                                                                                                                   
    # start up cubit                                                                                                                               
    cubit.init("-nojournal")                                                                                                                       
                                                                                                                                                   
    # import the file                                                                                                                              
    import_cmd = "import step" + "'" + input_file + "'"                                                                                            
    cubit.silent_cmd(import_cmd)                                                                                                                   
                                                                                                                                                   
    # get all of the volumes in the model                                                                                                          
    volumes = cubit.get_entities("Volume")                                                                                                         
    print "Found " + str(len(volumes)) + " volumes in the CAD model."                                                                              
                                                                                                                                                   
    # retrieve the export value and file extension                                                                                                 
    try:                                                                                                                                           
        export_key, file_ext = EXPORT_TYPES[export_type]                                                                                           
    except:                                                                                                                                        
        raise NotImplementedError("Unsupported export type was specified")                                                                         
                                                                                                                                                   
    # now export each volume                                                                                                                       
    for vol in volumes:                                                                                                                            
        # construct file name using dir, basename, volume index, and file extension                                                                
        filename = "'" + out_dir + basename + "_" + "volume_" + str(vol) + file_ext + "'"                                                          
        # insert export key and filename into command                                                                                              
        export_cmd = "export " + export_key + " " + filename + "volume " + str(vol)                                                                
        # export the file                                                                                                                          
        if dry_run:                                                                                                                                
            print filename                                                                                                                         
        else:                                                                                                                                      
            cubit.silent_cmd(export_cmd)                                                                                                           
                                                                                                                                                   
                                                                                                                                                   
if __name__ == "__main__":                                                                                                                         
                                                                                                                                                   
                                                                                                                                                   
    parser = argparse.ArgumentParser(description = "Simple script to separate a STEP file into its individual volumes using Cubit or Trelis "      
                                     "Please ensure the Trlis 'bin' directory has been added to your LD_LIBRARY_PATH and PYTHONPATH" )             
                                                                                                                                                   
    parser.add_argument("step_file", type = str, help = "Name of the step file you'd like produce volume files for")                               
    parser.add_argument("-e, --export-type", dest = "export_type", type = str, default = "stl", help = "Export type for the output volume files")  
    parser.add_argument("-o", dest = "output_dir", type = str, default = "", help = "Optionally provided location of output files")                
    parser.add_argument("-n", dest = "dry_run", action = 'store_true', default = False, help = "Option for printing potential output filenames wit\
hout executing anything.")                                                                                                                         
    args = parser.parse_args()                                                                                                                     
                                                                                                                                                   
    main(args.step_file, args.export_type, args.output_dir, args.dry_run)