It is always good practice to create your Sketchup forms correctly with all of the faces oriented the proper way, so that the front-face is facing outwards where you might see it and it has any required material/texture applied to it - and conversely the back-face is inside and never has a material applied, as it's not seen or rendered by Octane anyway [like most renderers]. The way the OBJ/MTL exporter works is that every face is exported as it has been modeled - i.e. if a face's front has no material the 'Default-Material' is used for that face. This can mean that you get unexpected results when rendering your model IF you have some incorrectly oriented faces - i.e. the back-face is actually looking outwards and has a material/texture applied to it, but the front-face is left without a material - it looks fine in the SKP but it is 'blank' in the OCS version. You can fix individual faces by sampling the back-face material, reversing the face and applying the material to the front face - repeating this for every wrong face ! This can be a big chore - BUT you should have made it right in the first place !!!
BUT I have now written a script for you to help fix this... unzip and place the .rb file into your ../Plugins/ folder
- (c) TIG 2010
Plugins > Fix Reversed Face Materials
Select entities including any suspect faces [edges etc are ignored].
If any face has a back-material BUT it has no front-material it is assumed
to have been made incorrectly and to be oriented the wrong way round,
with the desired material applied to the back instead of the front.
So then the face is reversed and its front-material is made to match the
back-material - including any UV-mapping appropriately corrected -
the back-material is then removed.
If there is no selection you are asked if you want to process the whole
model, if you reply "Yes" then absolutely everything is selected !
If the selection includes groups or components you are asked if you want to
process these too - if you reply "Yes" then any faces inside them are also
processed. If there are 'nested' groups or components with these they are
also processed through the nesting.
A closing dialog reports how many faces have been fixed.
To see the affect switch from Texture mode and view in MonoChrome mode, run
the tool and you should see the changed faces flip - switch back to Texture
mode and you should see no difference in appearance since all the materials
should still be the same, but incorrectly oriented faces have been fixed.
by PayPal to info @ revitrev.org
1.0 20100806 First Issue.
I was thinking about recoding the Exporter tool to use my 'deBabelizer' add-on - many of you might be familiar will some of my other tools - like the Extrusion-Tools - where you can have customized 'lingvo' files to translate the strings of text in menus/dialogs etc to suit your 'locale'. Would this be of interest to users ? If so then what languages would you like ? I will make the default 'EN-US' lingvo and often my poorly attempted FR/ES versions - which are immediately re-translated properly by native speakers and reissued [ ] - the editable text file format is easily understood, with the word/phrase string translations one per line with a 'separator' tag [<==>]... Other lingvo files can be made to suit any 'locale' that Sketchup can return using 'Sketchup.get_locale'. If a lingvo for a 'locale' file doesn't exist then the text will default to English [US] anyway... In addition to EN-US, FR and ES, I also have some tools translated to FA [Persian], D [German], ZH-CN [Chinese-simplified] and so on. I expect that the base set would be EN-US, FR, DE, NL, ES, IT etc. Most Chinese and Japanese [JA] translations are beyond me... but I am sure there are users who can make them and also for other languages I haven't listed too [like say Portuguese] ... Off on a tangent... even Esperanto [EO] is possible if you set your actual locale lingvo to contain the appropriate transaltions!
Comments on any of this would be welcomed...