Question 2D vertex shader on multiple sprite renderers

Hi everyone,
I am very new to shaders and I am trying to use the shader graph tool to skew a 2d sprite texture to create a shadow effect. In principle, I got it working:

The bottom sprite is using the standard sprite material, the top one is using a material with my shader. Both are using the exact same sprite asset.

However, weird things happen when I use the shader on two or more sprites. Suddenly it seems like the skew is applied from the world space origin:

Note that the two sprites are located exactly above each other in terms of world space coordinates, at (0,0,0) and (0,4,0), respectively - just as in the picture above.

Here is the part of my shader graph that produces the skew effect:


Everything works fine as long as I only attach the shader material to single sprite renderer - or if I create a new material for each renderer such that no material is used by more than one renderer. I originally came at this issue from here: https://www.sector12games.com/skewshear-vertex-shader/ and the shader code posted there produces the exact same effect as far as I can tell. I feel like I am missing something fundamental here about how shaders work. So if anyone could help, I'd much appreciate it.
Thanks!

 

Any solution?

 

Yes, actually. Sorry for the late reply.

The solution was to use the texture UV instead of the position node. Although I still don't fully understand the nature of the effect described above.

 

ok. Thanks I'm gonna give a try.

 

yeah! I have to agree......

 

I could not resist