[Plugin] OBJexporter v3.0 20130131

pilou

See the external links at the end of the page

thomthom

See the external links at the end of the page

Is that the official specs though? "martinreddy.net" ...

TIG

@tig said:

The D.P. accuracy is not now applied to 'whole numbers', and any -0 values becomes 0.

What made you chose to do this? Are there applications that doesn't handle these values well? I'm curious because I've been looking at the OBJ format this weekend.
(Is there an official specification somewhere? I find multiple sources around...)
It just minimizes the OBJ file size, an importer reads 0 as 0.0, so making it 0.000000 is pointless, -0==0 so it might as well be 0 !... so all trailing zeros are now omitted, it speeds up the writing by a few % and I also the importing at the 3rd party end...
There's an OBJ Wavefront Wiki...

thomthom

Are you sure all importers manage to read an int instead of a float which the specs appear to indicate? Just wondering in case the parsing is implemented in a stricter language...

@tig said:

I also the importing at the 3rd party end...

Something missing from that sentence?

@tig said:

There's an OBJ Wavefront Wiki...

This one? http://en.wikipedia.org/wiki/Wavefront_.obj_file

TIG

I have used OBJ files exported like this in many apps [Octane, Blender, MeshLab, MeshMan, AC3D etc] and they all import just fine.
As far as I can tell they expect a 'number', so 0 == 0.0 == 0.000000 etc, 1 == 1.0 == 1.000000...
They even take -0 == 0 when -0 is not really a number.
I also trap for 'NaN' and 'Infinity' which would break them...
Sharing vertex data is also permissible if you correctly reference the vertices.

Try it yourself using a box that is located at, and offset from, the ORIGIN by whole 'meter' distances. The native OBJ exporter using m/triangulation, flipped-YZ etc gives a similar result to my 'free' tool BUT 1.000000 >> 1 in mine... Now import the two OBJ files into an app like Blender and you get the exact same result... If you make the two much more complex you'll find mine loads into the app a tiny % faster. Of course it takes longer to write the file because the native exporter is a swifter exe...

thomthom

There are no way to define faces with holes in OBJ, is it?

I see that OBJ files can support bezier patches - which is interesting for Bezier Surface.

Mra

I'm getting a crash during export, albeit its a large file, the obj gets up to about 5mb and sketchup crashes without warning.

I'm aware this would be highly scene dependant but is there anything I can do? I'd be happy to send in a scene somewhere for debug.

chuckasaki

Firstly thanks for such a great plugin. I think it's a big rough that google want us to go all the way to 500 bucks for an obj export, something that could be considered pretty standard, and clearly exporting means that they may not even need all sketchup pros power as the model will be used elsewhere. I'd would love to see a slightly less expensive option, cos I ain't going to 5 without a good reason.
Having said that... I don't want to seem like someone whining about a freebie for sure, I think what you done is great..... but I can't get an export that works.
The model goes some way and then crashes- bugsplat . I can open the obj...sure.. but only half of it comes in.
Is your plugin still compatible?
If I can get results I will definitely donate.

TIG

As I have no way of knowing what it is you are trying to do then I don't have the feintest idea what's up.
My exported OBJ files have proved to be compatible with all of the standard apps that can import such files.
Have you tried exporting a simple box and seeing if that works...

Bugsplats during the export are very rare, if the SKP is large with complex geometry etc it can take a while to complete; so don't confuse a white-out with a 'crash'!
When Sketchup is doing intensive calculations it sometimes looses its screen focus and says it's 'unresponsive'.
However, it is still beavering away in the background writing the OBJ data etc.
Leave it alone until it's completed its tasks.
If you run it with the Ruby Console open do you get any error messages ?

If you still have issues and it's not just your impatience that's aborting things... then can you post [or PM] a sample of a SKP that is failing, so I can look at it...

For example do you have anything peculiar about your SKP files?
Like very small geometry, or very large geometry, edges and no faces, oddly grouped geometry, oddly layered faces/edges etc etc... ???

cotty

@chuckasaki said:

... google want us to go all the way to 500 bucks for an obj export

It's not google anymore

mommykathy

Thank You, Thank You, Thank You! Been going nuts trying to find something to do this and this is PERFECT. Have a great day!

McGyver

Hi! I'd like to thank TIG once again for this truly awesome plugin as well as all the subsequent updates.
I frequently recommend this plugin for people who are new to SketchUp, showing them that their modeling efforts can be used in other programs besides SketchUp.
A lot of people tend to believe that SketchUp is very limited, has no export options for the free version and are not aware of all the amazing plugins that extend SU's capabilities and give it greater power.
I was just writing a short "How to" for people who wish to use their models in Poser/DAZ studio, but it occurred to me that while I giving instructions on how to install a ruby script such as "OBJexporter" I was not sure if there were any other plugins that needed to be installed for OBJexporter to work properly... I have quite a few and the thought came to me when I was describing the progress bar and "Model exported in X# of seconds" features... so I figured I'd ask-

Does OBJexporter require any other plugins such as Progressbar.rb to function properly?

Thats probably a pretty stupid question, but before I tell someone how something works, I figured I should probably include any relevant additional information.

Thanks in advance for any information any of you can provide!

TIG

My OBJexporter code is 'self-contained'.
It only 'requires' sketchup.rb, and that is installed by SketchUp itself in the Tools folder...
The progress reporting etc is built-in to my code and needs no 3rd party helpers...

McGyver

Thank you once again!

the_bored_gamer

Hi, I press the OBJexporter button... then it ask to "convert all to png?".
Wether I press Yes or No, I get nothing, it just close. Please help!

TIG

Run with the Ruby Console open: this will report progress etc...
Tell us any error messages.
If you are working with a Selection it must contain Faces...

Are no files [OBJ/MTL] or textures' folder made at all ?
Do you have permissions to make files in the destination folder etc??

FantasyZone

OMG TIG!!!!!!!
I searched for a month a obj exporter for SketchUp and now I found your Obj Exporter an made an extra account on sketchucation just to download it and at last it worked!!!!!!!!!!!!! I am so happy now thank you for this FREE(!) ObjExporter

FantasyZone
PS. TAHNK YOU!

anar

Thanks TIG for this plugin.

It seems that groups are not exported with their SKP names.
For example if my group is named "Cylinder" the exported group name is "test-GRP-Cylinder-566-Color_A01" which is a bit annoying because I have to rename all my groups after exporting.

Also if I make a group with name "Level1" that contains 2 groups with names "Level2_A" and "Level2_B" without any other geometry, the group "Level1" won't export in the OBJ file.
Therefore ther is only one level of hierarchy exported...
Can it be a limitation of the OBJ format by itself ?

Cheers !

TIG

Anar

The 'grouping' in the OBJexporter file format is effectively 'by material'.
Each facet has a assigned a group based on:

ModelName-ContainerType-Name-ID-MaterialName

As Group names are no unique and Components can have multiple instances the ID is needed.

So for your:

test-GRP-Cylinder-566-Color_A01

Working right to left the geometry is thus...

MaterialName = Color_A01 [the Material's name, adjusted so its characters are OBJ compliant]
ID = 566 [assigned by SketchUp for the container's definition, during that session]
Name = Cylinder [the Container's name, adjusted so its characters are OBJ compliant]
ContainerType = GRP [Group]
ModelName = test [the Model's name, adjusted so its characters are OBJ compliant]

Note that if you had say 'Black' end facets then they would grouped separately as:

test-GRP-Cylinder-566-**Black**

anar

Thanks TIG for such a complete explanation !

But I still think it would be very useful if the groups could be exported with just their names as we can see them in the Outliner.
Then if the name isn't unique the exporter could automatically add a "_1", "_2", "_3", etc. at the end of it (for example).
I don't know if you see the need for it but when I export a scene with a lot of groups it takes me a lot of time to rename them back manually with the name I originally gave them in SU.

Maybe it could be an export option ?
I understand it would be more work on your side as the exporter doesn't have any "export option" window...

Still it's a good plugin that I use all the time ! Thanks !

Anar
http://www.reppersdelight.spacymen.com