How to achieve a smooth shadow

this is a sligthly modified SHADOW patch, I d like to know how it comes that the shadow has this irregular contour, seems like something to do with the mesh. How can I achieve a smoother shadow contour?

shadow.rar (18.6 kB)

Anti-alising obviously helps a lot but still you can see those little triangles over the edge of the shadow…
any hint ?

afaik you can (only) improve these edges via

  1. AA setting of the renderer (as you already did) and

  2. the number of pixels in Backbuffer Width / Height of your SHADOW MAP renderer.

lg, d

I ve found this nice shader called softshadow
thanks flux !