Octane Sketchup Exporter - 1025-02

[TIG]

There is a known limit to Sketchup and OpenGL.
You can't create faces of less than ~0.001sq" or ~0.1mm across.
The trick is to scale up the object - say x10, do the creation and scale back down again [x0.1] - the small facets will exists - it's just making them that is awkward.

There is no 'sensitivity' built into the Exporter - all faces are exported - they are all triangulated so if you small faces are not already triangular the built-in triangulation in the API's mesh tools might fall down when they are very very tiny...

Before we start blaming the Exporter or Octane itself for these 'missing pieces' let's be quite sure that there is no other explanation.
If you supplied a SKP of the 'faulty' part it would help.

For example, in the SKP, have you viewed this object in Monochrome-mode using a Style with distinctly different front and back default face colors [perhaps off-white and bright-blue], if you have facets that are reversed then these will show blue against the main white surfaces.
Because the Exporter only exports the front material that will be facing in the wrong direction on those facets and Octane will render the back material unexpectedly differently !

Or if you carefully examine these faces in the SKP in Texture-mode are they are truly in the same material ?
If you examine the 'rear' of this surface is it also 'seamless' ?

Incidentally, if this proves to be a 'size' issue then why do you need such exact scaling in the SKP ? Octane could not care less about the 'size' of what you are rendering so if it were all x10 it's 'real' size where is the issue ?

Please test some of my suggestions and supply the SKP and same OCS image for testing...

[smicha]

TIG,

I scaled my model x10. And all holes gone. Thank you again.

[smicha]

TIG,
sorry to bother you again, but I need your help.

I used Corel and Trajan Pro font. I exported the text as dwg and imported it in SU (I removed lonely vertices using Fredo tools). The final model - text HOME - is "pressed" - done as a component (glued to any, cut opening) and placed on a wall. The height of the text is over 5m and minimal spacing between vertices - about 1cm. In such scaling there are no holes in the text (but on my other models I encounter problem with holes even if I scale it). But if I zoom in to the "H" letter I see some cracks. Am I doing something wrong? Pease find skp and ocs files attached.

I appreciate your help.

smicha

[TIG]

It ought to be OK at the sizes you suggest?
Is its geometry that big, rather than a scaled 'group/instance' ?

If it's the latter then maybe you aren't scaling it up by enough in realilty ?
Looks like the serifs might produce tiny facets which will vanish when triangulated even smaller
You could also try scaling it up [x1000?], selecting all of its faces and use one of my tools like 'Triangulate Faces' [see SCG Plugins Index...]
Then scale it down so that the triangles persist.

When you now export it all of its faces will already be triangles so there might be no 'mesh' manipulation and thereby no lost faces ?

[smicha]

It ought to be OK at the sizes you suggest?
Is its geometry that big, rather than a scaled 'group/instance' ?
If it's the latter then maybe you aren't scaling it up by enough in realilty ?

Yes, it is geometry that big. I scaled it up to 5m height (lettering) to avoid cracks. When I scale it up or down in SU, cracks are still visible in Octane.

Looks like the serifs might produce tiny facets which will vanish when triangulated even smaller
You could also try scaling it up [x1000?], selecting all of its faces and use one of my tools like 'Triangulate Faces' [see SCG Plugins Index...]
Then scale it down so that the triangles persist.

When you now export it all of its faces will already be triangles so there might be no 'mesh' manipulation and thereby no lost faces ?

When I scaled it up 1000x the geometry is full of holes in Octane (strange?). Triangulation also doesn't solve this issue.

Is it possible that this is due to Octane and the way it imports obj? I tested 2.58e and 3.01, 3.02, 3.02a versions. I also tested drivers 301.42 and 306.23 - same results.

[TIG]

I know of no such issues
Can you PM me a SKP extract of your lettering, so I can look at it...

[smicha]

TIG,
I the above post there is a model.rar file attached with skp file.

[TIG]

I've looked at the SKP etc from your PM.
You have not made the lettering bigger, rather you have scaled the component-instance.
If I place a 'real' size instance it is much smaller, and therefore has some facets verging on the problem size BUT they should still work.
You ought to scale the original geometry inside the component and place a smaller version if needed - not make its geometry small and place larger version !

However, none of this of any importance

What you have discovered is that Octane has issues with certain combos of geometry !

I tested your SKP, exporting it separately into OBJ/OCS files for the large, small and large-exploded versions of the lettering, and also a Pro OBJexporter version of the OBJ file [for the large-exploded version].
They all produced similar renders - ALL with distortion on the top right serif of the H, the only difference being the small version having slightly elongated distortion.
Viewing the object from a different direction seems to give slightly different distortions, but still centered around the problem area [top-right]
Also the distortion in my OBJ version and the Pro OBJ is identical so it's not an issue with any distorted geometry in the base files per se.
There are images attached for each test.
I also reimported the OBJ back into an empty SKP and the geometry was fine, with no distortion or other issues.
There is considerable 'triangulation' compared to the original, BUT nothing very exceptional !
There are two images attached for this.

Can I suggest you raise this with Octane's guys separately, it does not seem to be a SketchUp issue at all - rather it seems to be a shortcoming of Octane itself in coping with certain forms...

[smicha]

TIG,
Thank you so much for your tests. I just did some extra work hoping to solve this issue. But I failed. Holes in geometry occur differently in various versions of Octane. Look at the screenshots.. I am preparing a post for Octane guys.

Regards,

smicha

[TIG]

Here's my final permutation: I pre-triangulated the faces in the SKP, then exported that mesh - very similar result in the OCS !