Hi all!

I'm quite new to Houdini. ..been trying to learn it for a couple of months now.
And right now I'm at a point where need some help.

Its about area lights.

First thing : in the ( grid ) area light, there is no option to adjust the width and height seperately.
So I linked it to a null and scaled that one -> works.
But there's gotta be a “better” solution for that.

I tried digging inside the area light and linked the width of the grid node to a new parameter in the toplevel called “areawidth” with this expression: property(“../areawidth”, 1). Its working in the viewport but there is no change in the rendering somehow…. Do I miss something? And is there a reason why arealights aren't meant to be rectangular in the first place?

2.: Is there a way to make area light shine in only one direction, without putting a blocker behind it ? a blocker box does work, but the increased shadow calculation seems really unnecessary.

Any help appreciated..

What if you use the area light with the line setting? That's what I did and it seemed to work OK.

you can create pointlight, add some rendering properties to it:
Area Shape
Area Size
Area Samples

then you can set shape to grid
size to x,y
you should get rectangular area light
(as soon as you change light type to area this parameters are ignores so keep it as point)

THX tamte! I'll try that out as soon I get home

And what about single direction area lights ?

i think it'll be the same (adding area properties), but instead of pointlight use spotlight with cone angle 180 and cone delta 0 (but you can set those values as you wish)

EDIT: but keep in mind that Area Size property is only for rendering, you'll not see any rectangle in viewport representing the scale
so you may want to link Area Size to underlying Grid3 SOP's size parameter and set Display flag to that Grid3 node