This is my first time making a mesh and i wanted to make a tree mesh. I tried out blender and I experimented with it and I have created one and have added it to studio. I want the tree to look full of leaves but for some reason the bottom of the mesh doesn’t exist as if it was 2d shape on one side. I want the leaves to be seen at every angle.
Here is what’s happening:
This problem could be that the mesh is not rendered properly.
The leaves have only one face so the normals can only point upwards, and the bottom looks transparent. Add the solidify modifier for the leaves in blender. However, since that’s 3 more faces per leaf, this method of making trees is inadvisable as it reduces game performance a lot unless it’s for showcases.
look up backface culling on google
I put that in but now it won’t let me add it into Roblox since it has too many triangles… Any suggestions?
Lessen the Tris of whichever has the most? Or change something that feels like won’t be noticed at some short.
STOP SUGGESTING THE SOLIDIFY MODIFIER
This is the worst thing you can do to solve this problem because you’re effectively ADDING 5 FACES FOR EVERY FACE, or in more technical terms, if the foliage sheet is comprised of a square (two tris), you’ll be added five additional squares (10 tris) because Solidify will turn it into a cube (six squares total, obviously).
It’s also known as a destructive workflow because once you apply the modifier it’s a huge pain in the ass to undo.
Before Solidify on a Plane
After Solidify on a Plane.
Instead
Select your foliage sheets in Object mode
duplicate the Object
Select one of the two, then in Edit mode, select the geometry
Press F3, and type “Flip Normals”, and press Enter.
And there, now you effectively have twice as much geometry, which still isn’t great (Roblox is still in the process of allowing us to make the backface actually visible, but I digress), but it’s sure as hell a lot better than using Solidify!
You can get better mileage out of your vertex count too if you merge your vertices (essentially having four vertexes share two planes facing away from each other, but that can get messy and is kind of destructive for the minimal benefit of less verts - so use it only if you want to.
its not a glitch. its only because blender supports seeing both sides of a face and roblox did not at the time, but you can apparently enable it now with this option in the properties of a mesh 
3D modeling software allows you to enable or disable the rendering of backface culling for modeling purposes as that is why you can see the back side of the normals, however when rendering or used in game engines backface culling is always used. To disabled backface culling in Roblox on a particular part such as the foliage you can make use of the new DoubleSided property for MeshParts.
For performance reasons you should make sure the foliage is a separate MeshPart from the tree so that the DoubleSided property only affects the foliage.
Related annoucement thead: MeshPart DoubleSided
Best fix i could think if is applying all transforms inside blender
Excuse my necropost, but I had this issue recently with specialmeshes inside parts.
5 mins of research led me to figuring out that if you (in studio) click on the part, it wont go away.
Based off that I have figured out you can create a highlight under the part, even with a outline transparency of like .99999, and it won’t diseappear.
I made a snippet to automatically do that for you
allstuff = workspace:GetDescendants()
for _, value in ipairs(allstuff) do
if value:IsA("Part")
and not value:FindFirstChildOfClass("Highlight")
and value:FindFirstChildOfClass("SpecialMesh") then
highlight = Instance.new("Highlight", value)
highlight.Name = "anti_backface_culling_ignore"
highlight.OutlineTransparency = 0.9999
highlight.FillTransparency = 1
end
end
Turning on the DoubleSided toggle doesn’t help?
In this case it will probably just show the bottom without a texture.
(just saw this is a post from 2020 lol this feature didn’t even exist back them)