Animated UV map stops mesh from batching

Unity Engine
1

I’ve modified the Animated Texture Tile script from the Wiki
( http://unifycommunity.com/wiki/index.php?title=Animating_Tiled_texture

so that my flat ‘sprites’ (flat planes) can cycle through 4 animation frames on a UV map. I have 20 instantiated sprites, using just this single texture, all batched under 1 draw call. It works well but only later did i notice that after applying this script to my prefab sprites it stopped them from batching and all 20 drawcalls were back. The bitmap is 512x128.
Can anyone point out to me some change I may have made to break the merged mesh/texture/prefab routine that leads to the object no longer batching?

2

Ok, I’ve figured it must be something to do with the texture constantly updating between the various UV coords to achieve the flipbook effect. These two commands at the end of the script

   renderer.material.SetTextureOffset ("_MainTex", -offset);
 	renderer.material.SetTextureScale ("_MainTex", -size); //

are doing the damage.

Has anyone made a sprite-sheet UV animation script that is Drawcall friendly ?

3

The reason this is batching is that by updating the offset and scale, you’re making a new texture.

I bet if up the UV’s of the model directly without altering the texture, it will batch.

4

Yes that makes sense. Is there a method for updating/modifying the UV’s in a sequence similar to that of a sprite sheet i.e No of frames,frames per second?