Metropolis Light Transport Script

MetropoLight http://www.3dvirtualight.com/mlt is a freeware GI renderer that makes good use of the Metropolis-Light-Transport-Algorithm. It is supposed to be a good algorithm for scenes where the light is coming in from a small opening.

I wrote a little script that exports to the MLT format so you guys can experiment with it.
http://home.comcast.net/~gamma-ray/metropolight.py

thanks, scorpius!
it’s working
http://img425.imageshack.us/img425/9576/img048df.jpg

:frowning: after few trys:
mesh smooth did’t work
uv export didt’ work
multiply material …
ks …
kspow …

If You wrights clearly what script can do I coluld save some time.

I added a few new features:

  1. Text, Surf, Curve, and MBall objects (in addition to Mesh) are also exported.
  2. Smooth vertex normals are supported.
  3. Specularity is exported, but beware that this produces unexpected results if a high hardness value is used.
  4. The code has been optimized and runs 4 times faster for very large meshes.

So the only two things to do is UV and material indices.

cool!! can’t wait

Be careful with the specularity/hardness settings. I emailed the author and he said that glossy objects actually reflect light and contribute to the “final gathering.” So it doesn’t just put a highlight on your smooth objects.

Hi Scorpius
I’ve got the same errors on varius test scenes and Python ver (this is from python 2.2.2 and 2.3.5):

Using Python version 2.3
Traceback (most recent call last):
  File "metropolight.py", line 308, in ?
  File "metropolight.py", line 295, in main
  File "metropolight.py", line 148, in write_global_verts
NameError: global name 'set' is not defined

win xp, blender 2.37a

EDIT: It’s working preety good for b2.4 - no errors (unexpected errors :wink: ) and all supported func seems working

500 mutations and rendertime about 1.5 h
http://img103.imageshack.us/img103/8347/02bh14nv.th.jpg

EDIT: 1500 mutations (no postpro - only gamma and brightnest):
http://img203.imageshack.us/img203/7562/02bhpp1uf.jpg

MetropoLight is about as useful as a fart in a spacesuit.

Unless you want to spend hours producing grainy renders that look like garbage.

thanks for the script tho! I won’t use it :wink:

:smiley: yes, I agree and probably next year nobody will remember it - but there is no other free metropolis light transport rendering engine

Like Stephane Marty (writer of MetropoLight) already explained on the MetropoLight site:

I developed this small rendering project to study and to familiarize with this new approach in random walk global illumination algorithms.

Although some additional features will be progressively implemented to complete the project, MetropoLight doesn’t claim to become a sophisticated renderer. It just has to be considered as an experimental rendering tool.