Custom made shadows

Scripting Issues
1

Hello Panda3d comunity,

My first 3d app is growing well thanks to this great python engine !
it’s called Astrini (standing for intitiation to basic astronomy facts)
intended to become a pedagogical software.

the source is on github:
github.com/webplate/astrini
I hope this software isn’t too buggy (don’t hesitate to report misbehaviours)

But I’m not writing here for a showcase as astrini is far from finished. I’m here to ask some advice to better control the projected shadows of my planetoids. For the moment I use a DirectionalLight with setShadowCaster to true in order to show moon’s shadow on earth (location of sun eclipse) and earth’s shadow on moon (moon eclipse).

I would like to control more precisely the darkening of my models where the shadow are casted. Idealy, I would like to show them without using the shadowCaster in order to avoid the jaggy aspect of a low resolution projection and to be able to align at wish these darkened areas with the shadow trails I designed (activate them with the shadow button).

At first I imagined having two versions of earth and moon (an illuminated and a dark one) and then using clipping planes to show darkened areas properly… but the doc says the clipping planes shouldn’t be used :frowning:

So may I ask how would you proceed ?

2

You have only round geometric objects, so I think that you can try to use only mathematical functions in shader instead of rendered shadowmap image to avoid low resolution problems, but of course it require rewriting shaders.

3

Thanks for your advice,
I’ll try to learn about shader’s rewriting, it seems a good idea.

And a HUGE thanks for your work on YABEE, this tool is so useful !
Luckily there’s still some russian geniuses to care for us :slight_smile: