Integrating ESM to MagiEngine

Try to find a suitable SM algorithm to intergrate to my engine, just come across an new SM named Exponential Shadow Maps.

The result is pretty good and avoid the light bleeding in VSM.

Here is the FX composer rendering result:

 

 

 

The performance of ESM is a lot better than PCF softshadow and consume less video memory compared to VSM.

Of course, the result looks pretty decent to me.