In Creation kit, objects are transparent on one side?

[chucksteel]

No not unless your talking about deleting vanilla objects. An example is an ITM "Identical to master", these are edits that happen by accident. Most of the time it comes from just looking at something in a cell and the Ckit suddenly it thinks you edited it.

 

so say you pop into a cell that uses that staircase you want to duplicate and move it, open the form or just breath to heavily the Ckit will think you edited the form and the cell in your mod.

[DeathMotif]

Your question has to do with the way 3D modeling works in most environments. Meshes are composed of vertices, triangles, normals, and uvs. There can be others, but these are the most common. Vertices represent a point in three dimensional space. It takes three vertices to form a triangle. The normal is a vector that is perpendicular to the face of the triangle. Note that this is not the only implementation of normals. This is just a simplified version for the purposes of this example. UVs are 2D coordinates in texture space. Implementations may vary, but they are usually expressed as percentages of horizontal and vertical space ranging from 0 - 1, where (0,0) is the upper left corner of a texture and (1,1) is the lower right corner of the texture.

This is where your question comes in. Traditionally, triangles are only visible from one side.

Suppose we have the following vertices: 1: {1, 0, 0}, 2: {0,1,0}, 3: {0,0,0}
If we were to order them clockwise: 1, 2, 3, then the triangle will be visible looking at it from a positive Z vector (IE the direction you are looking at the screen).
If we were to order them counter clockwise: 1, 3, 2, then the triangle will be visible looking at it from a negative Z vector (IE from the screen looking out).

This is the reason why parts of a mesh are invisible. You are looking at them from behind, which isn't visible. Like what was said earlier, it is possible to turn on visibility of both sides of a triangle at a significant performance cost. Now you are effectively treating each triangle as having two faces which means twice the data processed even though you are using the same vertices. It's generally best to avoid doing this.

Finishing this discussion out for completeness, meshes are created by storing these vertices typically as an array of Vector3's. Triangles are stored as an array of integers pointing to references to the indices of these vertices with every three references representing a triangle. Normals are usually calculated through the importing software in most game engines. And the vertices are mapped to 2D coordinates and stored as Vector2's as part of our UV mapping.

The UV coordinates tell how to apply the texture to the face of the visible triangles in the mesh. This applies to all texture files being used by the shader, so that they all apply to the same faces appropriately. As for shaders and textures (materials), that is another topic for discussion.

Please note that this was written impromptu without the aid of other sources. Any errors are mine, but can be readily remedied through simple google research.

[ThatSpartacusGuy]

Textures are applied only on one side in general (as most static objects are only visible from one side) . If you need it to be double sided (be aware in-game that can have performance impact) you can open the nif-file of that particular object and change the shader flags 2 and activate double sided.

 

CL

 

Also, don't forget that the shader flag will most likely be ignored if the Shader Property has a name that links it to a material, as I just found was the case with my CBBE vault tec security armor replacer. Working on fixing that soon in an update. Thank you for this info, couldn't wrap my head around why this mesh was textured one sided. The meshes are CBBE conversions of the original, so my knowledge was limited.