Exploding distorted textures

[Bosseye]

Morning

How do I now explode a distorted texture? Used to be a case of right clicking the texture in Sketchup, selecting UV mapping and selecting the option then saving the exploded distorted texture somewhere, but that doesn't appear to be an option anymore? Indigo v3.4.4

Thanks,

Edit - I'm getting a triangle UV index out of bounds error now. I've tried mucking about with the UV mapping in the active mesh dialogue but I can't see a way to sort this out I'm probably missing something simple.

[Pibuz]

..not sure I understand the question..
Could you please post a sample image?

[Bosseye]

No problem - see below.

Sketchup model - textures projected onto the geometry from a matched photo.

Renders like this:

I expected it to render incorrectly, but it used to be easily fixable - the problem I have is I can't find the new way to explode the distorted textures.

On my older version of SKindigo 3.1 you would right click the texture, UV mapping, then 'explode distorted texture'. This would allow you to save the distorted texture as a jpeg which would then allow it to render correctly in indigo, but the UV mapping option is no longer an option in 3.4.4, or if it is its moved somewhere I can't track down.

[Pibuz]

Oh, ok...
Sorry, I can't answer your question...I rarely use projected textures...

..Have you tried exploding the group maybe?

[Bosseye]

Thanks for looking anyway. Its not a group, so theres nothing to explode - its purely a distorted texture applied to a face. It just needs exploding and saving and it will all work, as I've done a million times before.

Very frustrating when basic functions move around on later versions! Client will have to wait......

I have searched the forums and the manual and although it might be me not looking hard enough, I can't find anything relating to where UV mapping might have gone or been altered in this revision other than the note in the 3.2 stable release thread about improvements to how distorted textures are handled. It must be around somewhere. As above, the closest I can find is the UV mapping sets under 'edit active mesh' but this either makes the problem worse (renders more distorted) or introduces the triangle UV index error

[galinette]

Not a real answer, but if you subdivide your mesh in sketchup (not indigo) this will reduce the effect a lot.
It comes from the fact that perspective projection of textures are not uv linear, instead they are u/z and v/z linear, z being the depth from the texture projection frustum.

Now for the think tank, one very elegant approach for solving this, even better than export of a distorted texture, would export (u/z,v/z) in one uv set, then 1/z in another uv set, and a shader would then do the correct uv sampling at coordinates : u=(u/z)/(1/z), v=(v/z)/(1/z). This would allow direct use of projected textures with exporter work only.

[Bosseye]

Hmmm, tried that - right click, 'edit active mesh', max subdivisions 20, no change to the render unfortunately.

I might email the main support address, I could do with a resolution on this as client is waiting on the image...

[Bosseye]

Ok, have come up with a workaround. A horrible, messy method, but works. Right click each texture, make it unique. Re-apply the unique texture from the Sketchup materials window using the paint bucket, then edit the texture and move it around until the orientation is more or less correct on the face.

[Pibuz]

One question: from your image, seems like the base geometry is very simple.
Why not saving the exported image (right click on the material, save as...) and attach it as a simple taxture on a plane? (just a workaround)

[galinette]

Hmmm, tried that - right click, 'edit active mesh', max subdivisions 20, no change to the render unfortunately.

I might email the main support address, I could do with a resolution on this as client is waiting on the image...

Yes, this is what I called subdivide in indigo. This setting just tells indigo to subdivide but does not change the exported mesh.
I was mentionning subdividing with a grid inside sketchup (so that the sketchup object really has small faces) but I have no idea how to do that in fact.

[Bosseye]

Yes, this is what I called subdivide in indigo. This setting just tells indigo to subdivide but does not change the exported mesh.
I was mentionning subdividing with a grid inside sketchup (so that the sketchup object really has small faces) but I have no idea how to do that in fact.

Ah, I see. Yes, that might work.

One question: from your image, seems like the base geometry is very simple.
Why not saving the exported image (right click on the material, save as...) and attach it as a simple taxture on a plane? (just a workaround)

I think that's essentially what I've ended up doing just without the export step - making the texture unique seems to do the same thing, then apply it to the face and then adjust it manually. Not as neat as the old method, but works.

Thanks for your input guys.

[Polinalkrimizei]

looks like a ether trip!