Why is Unity using GL_TRIANGLES not GL_TRIANGLE_STRIP?

Archived Forums Questions & Answers
1

Just curious why this is or if there is a way to change this.

Thanks :slight_smile:

2 Answers

2
3

I kind of agree with @Mefistofel: it’s hard to organize complex meshes in triangle strips or fans, what makes simple triangles a better choice. Besides this, modern shaders usually spend much more cycles in fragment programs than processing vertices (this may not be true for a complex model at a long distance, but as said above complex models are hard to convert to strips/fans). By the time OpenGL was created, the available hardware barely could process vertices at decent frame rate, thus optimizations like triangle strips or fans could make a big difference, but with modern GPUs things changed so much that there’s a trend towards vertex proliferation via tessellation shaders.

So if I've optimised my own mesh for strips I still can't use strips? EDIT : I'm using mobile GPUs just FYI so I would like my character mesh to use TRIANGLE_STRIP along with transform feedback

 –

I've not found many details about how Unity renders meshes, but it seems that in the past you could define the mesh topology as MeshTopology.TriangleStrip and pass the strips via SetIndices, but this isn't available anymore. Take a look at [this post][1] in the forums - it seems that a non-documented function may help you (if it yet exists in Unity 4.x, of course). [1]: http://forum.unity3d.com/threads/149469-Draw-mesh-as-Triangle-Strip

 –
2

Triangle strips are not used for three unique vertices(as usual triangle), they use one unical and two previous vertices from previous triangle.
To use this, you need collect special vertex arrays. They have a limited ways to use, such as to render the landscape (it is necessary to transfer less points - more polygons can be rendered).
For usual purposes such mode is not suitable.

... Sorry if this sounds rude but I asked why this is and is there a way to change it, I know (probably too much) what the two functions do haha but thanks Also I don't think I've ever seen someone say that triangles is usually more suitable than strips. :\ EDIT : Strips uses less vertices and therefore less processing by vertex shader is the reason strips are usually better than triangles and why fan is better than strip.

 –