Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - cptSwing

Pages: [1]
I agree that it would be good to offer the option to embed tangents in the exported gltf file.
That said, more explanations are due. The situation regarding tangent spaces in Painter is currently the following :
  • If your original mesh had tangents when importing it in Painter, Painter would use that tangent space.
  • If it did not, Painter recomputes the tangents using the MikkT code.

The differences you are observing may be because you imported in Painter a mesh with tangents which were not computed with MikkT in the first place.
Also, another thing worthy of note which may be causing the differences you are observing : making sure that you are using the exact same tangent space at each vertex (by either using the same code or by shipping the tangents with the mesh) is not sufficient for ensuring you will decode the normal maps in the same way in all software. You also need to apply the same code for interpolating the tangent spaces at each fragment within the triangles. Some software like UE4 choose to interpolate the normal and the tangent and recompute the binormal as a cross product of the other two at each fragment (multiplied by a sign to properly handle mirrored uvs). That's for example the case for the Unreal Engine 4. Some other software, like Unity, choose to interpolate the normal, tangent and binormal without further changes. Those are the two more common options but of course each software could possibly make a different choice (like renormalizing the vectors at each fragment, or even go as far as reorthogonalizing the tangent frame using the Gram-Schmidt process). Currently, Painter let's you choose between the "UE4" way or the "Unity" way of interpolating the tangents (the option is set in the project preferences). Eventually, we will probably do the same thing in Painter that we are currently doing in Designer and let the user be able to implement whatever algorithm they want to use both for computing the vertex tangent space and interpolating them in plugins with a common API.

So I am understanding this correctly: When I import a mesh without tangents into SP, SP creates them according to MikkTSpace. When I export my model and textures as .gltf though, these tangents are stripped out again? I am not sure how this helps with anything. I think both three.js and babylon.js will make use of imported tangents, however will not recreate them themselves.. which leaves us MikkTSpace-tangent-less once more ;-)

A quick fix for this is to go into the graph properties and move the "diffuse" output below "basecolor" in the "Output Images" tab. Won't work for SBSAR files, obviously ;/

Sent you a pm, thanks for the support!

Bump.. this has cost me 2 - 3 weeks of work, and since I can't trust 2.6, I'm effectively barred from continuing work on my backup file :(

This has just happened to me, out of the blue. I have 4 saves of my project file, with a two hour span of having saved them - I exported my textureset, closed SP and bam I can't reopen any of the files, with the above error showing up.

Please tell me it can be fixed, or it'll have to be ritual suicide for me.

EDIT: Log added

+1 pretty please. Just 1 color more and dragging the pins around would be so helpful.

Pages: [1]