PNG's result in artifacts

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Produce a object with a png texture
2. Load up in processing
3. Watch as your model has random inverted normals

What is the expected output? What do you see instead?
I expect to see a nice model, but with a PNG texture, the model instead 
produces artifacts, mostly which appear to be flipped normals.

What version of the product are you using? On what operating system?
OBJLoader 23b, Blender 2.61 (custom build, r43252) is the exporter, Windows 7

Please provide any additional information below.
If you use a JPG, it turns out alright. Could fix the bug or either post 
something in the documents about the problem with using PNG's

Original issue reported on code.google.com by Josh.Mi...@gmail.com on 23 Jan 2012 at 9:35

[GoogleCodeExporter]

Hi Josh,

What you're probably seeing is sorting artefacts from a texture with an alpha 
channel. Check the PNG file doesn't have transparency or an alpha channel. At 
this stage there is no support for sorting the triangles in the object before 
drawing it. 

if you can supply a demo of the problem I can tell for sure.

Matt Ditton

Original comment by mattdit...@gmail.com on 23 Jan 2012 at 9:41

[GoogleCodeExporter]

You were right

Applying a white background / removing the transparency allowed it to display 
properly

Thank you for clearing that up

Josh Milas

Original comment by Josh.Mi...@gmail.com on 25 Jan 2012 at 3:12