added a command line interface

render.py

@@ -0,0 +1,66 @@
+#!/usr/bin/python
+
+import os
+import sys
+import os.path
+from optparse import OptionParser
+import re
+
+import world
+
+helptext = """
+%prog [-c] <Path to World> <image out.png>
+%prog -d [-c] <Path to World>"""
+
+def remove_images(worlddir, cavemode):
+    if cavemode:
+        cavestr = "cave"
+    else:
+        cavestr = "nocave"
+    imgre = r"img\.[^.]+\.[^.]+\.{0}\.\w+\.png$".format(cavestr)
+    matcher = re.compile(imgre)
+
+    for dirpath, dirnames, filenames in os.walk(worlddir):
+        for f in filenames:
+            if matcher.match(f):
+                filepath = os.path.join(dirpath, f)
+                print "Deleting {0}".format(filepath)
+                os.unlink(filepath)
+
+def confirm(imgfile):
+    answer = raw_input("Overwrite existing image at %r? [Y/n]" % imgfile).strip()
+    if not answer or answer.lower().startswith("y"):
+        return True
+    return False
+
+def main():
+    parser = OptionParser(usage=helptext)
+    parser.add_option("-c", "--caves", dest="caves", help="Render only caves", action="store_true")
+    parser.add_option("-d", "--delete-cache", dest="delete", help="Deletes the image files cached in your world directory", action="store_true")
+    parser.add_option("-p", "--processes", dest="procs", help="How many chunks to render in parallel. A good number for this is 1 more than the number of cores in your computer. Default 2", default=2, action="store", type="int")
+
+    options, args = parser.parse_args()
+
+    if len(args) < 1:
+        print "You need to give me your world directory"
+        parser.print_help()
+        sys.exit(1)
+    worlddir = args[0]
+
+    if options.delete:
+        remove_images(worlddir, options.caves)
+    else:
+        if len(args) != 2:
+            parser.error("What do you want to save the image as?")
+        imageout = args[1]
+        if not imageout.endswith(".png"):
+            imageout = imageout + ".png"
+        if os.path.exists(imageout) and not confirm(imageout):
+            return
+        imageobj = world.render_world(worlddir, options.caves, options.procs)
+        print "Saving image..."
+        imageobj.save(imageout)
+        print "Saved as", imageout
+
+if __name__ == "__main__":
+    main()