This is my "Perspective Shadow" filter (in Gimp 2.10)-
Totally derived from the original:
Perspective-shadow.scm version 1.2 (2000/11/08) by "Sven Neumann <sven@gimp.org>".

I ported it to python (and gimp 2.10) and added the possibility to create a shadow in front of the subject (angle > 180).

It has the same limitation of the original (the subject is considered as a 2d object, hence the shadow is created starting from the "base line" on the subject)

If someone is interested, here it is.

Starting with this image (and selecting the dark silhouette)

you may get the shadows shown in the subsequent post.

Examples using angle 225 (in front) and 45 (back)

Examples using angle 213 and 33.

How interesting this possibility. Thanks Dinasset. I really use few times shadows in front of the object but it's great to have it.

Thanks.
You may try to:
- take a photo of a sunset
- take a silhouette of your grand-child
- place it with the appropriate size and position
- calculate approx the angle from the sun and the silhouette
- run the filter after having selected the silhouette….

Here's an additional challenge for you

As we discussed some years ago, as you've rarely got a point light source, the shadow should get increasingly blurred the further from the object it gets: viewtopic.php?f=9&t=8989&p=116497&hilit=shadow#p116497

My try. I like it.

Do you really need a script for everything?

A selection and the transform tools + gradient tool usually works

A bit about it here https://www.gimp-forum.net/Thread-Shado ... 739#pid739

ehehe….
yes, Rich, I'm a lazy filters man ...

edit: BTW, Rich, the original filter is about 20 years old, hence I'm not the only maniac...

the filter has the blur option, but it's the same as the original, not really as it should be


This filter is only a porting into python plus gimp 2.10 with the addition (required some time ago, but I do not remember by whom) to allow the shadow in front of the subject (backlight).

Wow, excellent Issabella.
So you will have situations where to use this filter.
I'm sure you too make "backlight" photos...

Thank you very much, Dinasset. I have done the shadows manually but like you, I use the filters more and more to do something. Saves time. Thanks again!

Accepted the challenge.
Reshaffled the filter, simplified, and added the distance-blur.




It remains something to play, not a "serious" filter.
The new version is here:

Thank you Dinasset. I got this outcome after selection the object.

The problem as I see it, is that Gimp 2.10 already comes with both Perspective Shadow and Advanced Perspective Shadow, so why the need for such filter? At the very least, you should rename it to something else and put it in the "Light and Shadows" category.

@racer
If you can get a shadow also in front of the subject (and not only beyond), you're perfectly right, but:
- in my 2.10 as published (samj) I have only one of those 2 mentioned (Perspective)
- it still has the same limitation to allow only an angle <=180
If you can get a perspective shadow with an angle > 180 with the second one mentioned, fine, just ignore my post.
As told in my initial post, the main difference is exactly the angle treatment.

Thanks anyhow for your comment

Yes, you are right, The "Advanced Perspective Shadow" was an add on SCM script and it is also limited to 180 degrees. I edited your script to show up in Light and Shadows. It works OK, but doesn't line up right in foreground shadows. It's easy enough to fix though.

Thanks...

Racer,
feel free to post here your amended version, any improvement is very well welcome.

No, I meant fixing it in post. I don't know how to code a script other than basic things.