Dynamic game programming

General Discussion
10

You are definitively right.
So, I commented out the concerned line in the Finder class. Then, i wrote 2 classes that allow dynamic rebinding triggered by file modification.

So, they monitor the source directory and reload a class file every time you save it. I like it this way because it does not depend on the editor you’re using.

I’m not an experienced python programmer, so feel free to comment

# FileChangeNotifier.py #

import os
import thread
import time

class FileChangeNotifier(object):

    def __init__(self, path, callback, interval=0.5):
        self.path_to_scan = path
        self.files = {}
        self.callback = callback
        self.interval = interval
        self.is_monitoring = False


    def __stat(self, filename):
        stat=os.stat(filename)
        return str(stat[6]) + '_' + str(stat[8])
    
        
    def __walkCallback(self, args, directory, files):
        for file_name in files:
            if file_name.endswith('.py'):
                filename = directory + '/' + file_name
                if self.files.has_key(filename):
                    nrepr = self.__stat(filename)
                    if not nrepr == self.files[filename]:
                        self.files[filename]=self.__stat(filename)
                        self.callback(filename)
                        
                else :
                    self.files[filename]=self.__stat(filename)
                

    def __monitor(self):
        while self.is_monitoring :
            os.path.walk(self.path_to_scan, self.__walkCallback, '')
            time.sleep(self.interval)

    def startMonitor(self):
        self.is_monitoring = True
        thread.start_new_thread(self.__monitor, ())

    def stopMonitor(self):
        self.is_monitoring = False

#########################

# ClassUpdater.py #

from direct.showbase import Finder
from FileChangeNotifier import FileChangeNotifier


class ClassUpdater(object):
    
    def __onFileChange(self, filename):
        try:
            Finder.rebindClass(None, filename)
        except Exception, ex:
            print 'Exception while rebinding the class :',ex
            
    
    def __init__(self, directory, interval):
        self.fcn = FileChangeNotifier(directory, self.__onFileChange, interval)
    
    def start(self):
        self.fcn.startMonitor()
    
    def stop(self):
        self.fcn.stopMonitor()


#########################

# Example of use (go.py) :

from ClassUpdater import ClassUpdater
from MyWorld import MyWorld


w = MyWorld()
c = ClassUpdater('.', 1)

c.start()
run()

I open a shell, start ppython, type “execfile(‘go.py’)” that execute the above script, and everything is fine.

Thanks a lot David, this is even better that what I was expected.
Is there a place where I could place this stuff in the wiki ? I also have a VC8 project compiling pview that could be useful, regarding to how many people ask how to use Panda in C++

(edit : fixed a “print” bug)