hello conitec,

currently I have some problems with getting different types of lights work properly in my shader and hope you have some answers to it.

The first problem is, that I can't separate between the different kinds of lights, so I have no Idea how to execute different code for directional, point- and spotlights. Currently I just treat everything as a pointlight.

The second thing is about the sun in combination with pointlights. If I treat the sun as a biiig pointlight (which is the default, because it's in the vecLightPos array) it's deactivated when the model is in the range of too many other lights, because it has the biggest distance. It looks really strange if the sunlight suddenly disappears. Maybe that could be fixed by making the sun the first light in the list.

I thought also about using vecSunDir and calculate it as a real directional light, but then you calculate the sunlight twice, because the sun position is still in the list of lights, which is of course not acceptable.

So, till now I didn't found a satisfying solution to this problem and hope, you can clear things up a little
Scorpion

Im still new at shaders, but as for using VecSunDir, I think it may be possible.

I dont know about the programming side of it, but from a concept point of view,
couldnt you process VecSunDir first, and then process all the VecLight's next.
But only process the VecLight if(VecLightPos[x]!=VecSunPos).
That way the sun will only be processed once, whether it is in the VecLight list or not.
I have no idea on the efficiency of this concept though.

What you need for spotlights is vecLightDir, its non zero when you have a spotlight. All 3 sorts of lights are in the light array.

The problem is, that I don't know the index number of the sun in the array (or some kind of flag, etc.).
If I evaluate vecLightDir, the sun would be treated as a spotlight (because it has a direction, too), which is even worse...

So all in all I am looking for a correct way of identifying the different light types and a way of avoiding the sudden forfeiture of the sun.

The sun is the last light in the array. Here's the info to identify the lights:

vecLightPos.w > 10000 -> sun
vecLightDir.w > 0 -> spotlight
Otherwise -> pointlight

Wow, love your easy and simple answers to my so puzzling problems^^

Thanks!