Jump to content
Sign in to follow this  
reeson

Extrude by colour

Recommended Posts

Hey guys. I'm trying to get extrude by colour to work, but I'm failing hard. What I have is a grid that I painted some spots over with red colour. Now, how can I extrude only red colour, with a falloff? I did find some old videos for Houdini 15, and I tried to recreate, and it doesn't work. Cheers!

exturde by color.hip

Share this post


Link to post
Share on other sites
  1. It is better to paint on a black surface right away, because that way all color channels are initially set to 0.
  2. After painting you should promote colors to primitives, because this is what primitive extrude is working with.
  3. If however you have chosen to paint red on white, the red channel will be set to 1 everywhere. Red = 1,0,0 and White = 1, 1, 1.
  4. Thats why the green or blue channel is more distinctive here: Set your primitive wrangle to f@r = 1.0 - @Cd.g; so its able to tell where red is being used.
  5. Inside the primitive extrude set 'distance' to something larger than 0 and set 'distance scale' to r.

 

exturde by color_corr.hiplc

  • Like 1

Share this post


Link to post
Share on other sites

Thank you. I see now. It's easier with a black base colour. So once I paint over with red, in primitive wrangle I just type f@r = @Cd.r 

Cheers!

 

Share this post


Link to post
Share on other sites

Is there a way to add an additional noise on top of the extrude by colour without adding another PolyExtrude SOP? I'm trying to do this with Att. VOP, but no luck. Here's my hip file.

color_extrude1.hip

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×