XNA Tutorials, Samples and Thoughts
Adding softness to shadows
In my efforts to make the shadows soft, based on the formulas for penumbras, I finally realized that my method does not support physically correct penumbra softness, but I will explain the reason for this when I do the tutorial.
Until then, here’s what I came up with, after applying some Gaussian blur to the final shadow image. (variable degree of softness)
Even if it’s not physically correct, I still think the softness looks good enough.
There’s also an interesting looking result when the radius of the Gaussian Blur depends on the distance from the light…
| Print article | This entry was posted by Catalin Zima on October 1, 2009 at 10:58 pm, and is filed under 2D, XNA. Follow any responses to this post through RSS 2.0. You can leave a response or trackback from your own site. |
about 2 years ago
That is pretty cool, the radius trick makes the light diffuse, witch is physically correct.
about 2 years ago
Wow – really cool! I’m really looking forward to the tutorial! Nice work.
about 2 years ago
Looks fantastic! Can’t wait for the tutorial!
about 2 years ago
Amazing… Looks very nice, love to see that a tutorial is coming, thanks!
about 2 years ago
Can’t wait for this, looks fantastic!
about 2 years ago
Really good effect, looks pretty correct.
about 2 years ago
That looks awesome, and efficient. Thanks!
about 1 year ago
Is this tutorial going to be published soon? I’ve been doing some googling around and I can’t find any sources on how to do this, so it would be really appreciated!
about 1 year ago
Woohoo!
I thought I was the first one to figure out how to render 2D shadows on the gpu, but it looks like you got to it before me.
I’m using a “stretchy” shadow method and drawing my objects over the shadow casters. I thought about using a gausian blur for the penumbra effect, but I didn’t think it would turn out that good, and the distance based method looks amazing!
I’ll be implementing that in my light engine and adding credit for you.
If you have any source for this, it would be much appreciated, regardless of the complexity / messiness.
about 1 year ago
Or not.. I just read your method works on rasterized images. Now I’m very intrigued.
about 1 year ago
A thought:
Make the blur depend on the distance from the shadow caster, not the distance from the light source.
The shadows that start far away from the light with blur using distance from light already have diffused light behind them when they start. This seems wrong to me.
This looks great. Looking forward to the example. Keep up the good work
about 1 year ago
Would love to see this tutorial! Been trying to implement some shadows and they just don’t look right.. Trying to add dynamic shadows to 2D tilemap..