Gradient descent is an optimization algorithm used to minimize some function by iteratively moving in the direction of steepest descent as defined by the negative of the gradient.

Pragmatic VEX series is aimed to increase the technical capacity of the artists and TDs which will allow them to tackle more complex production shots with complete control and ease by acquiring a deeper technical understanding of how things work in Houdini at the lowest level with a strong applied focus on high-end feature film visual effects production.



Senior FX Technical Director @ Industrial Light & Magic | Feature film credits include The Lord of the Rings: The Rings of Power, Marvel's Eternals, Star Wars: The Rise of Skywalker, X-Men: Dark Phoenix, X-Men: Apocalypse, Aquaman, Alien: Covenant, Pirates of the Caribbean, Justice League and many more.

More from Yunus Balcioglu


  • rlvelocity 3 years, 1 month ago  | 

    Hi. How are you getting the network editor to display as an overlay in your viewport window? I've never seen this done before and I searched both the network and viewport display options. Thank you.

  • animatrix_ 3 years, 1 month ago  | 


    The default Houdini doesn't have this functionality. I achieved it by writing a lot of Python Qt code. You can see it here:

    Additionally if you like to see this feature in Houdini, please send an RFE to SESI so they can consider adding this to Houdini :)

    • rlvelocity 3 years, 1 month ago  | 

      awww, dang. I had a feeling that since you are a senior TD that was going to be your answer :) I will submit an RFE now asking for that as a built-in feature. Thanks.

  • Ygaillard 2 years, 2 months ago  | 

    Hey ! It didn't work for me. When I applied the wrangle, I had this error

    Invalid source /obj/gradient_ascend_heightfield/attribwrangle3/attribvop1
    Error: Vex error: Unable to load shader 'op:/obj/gradient_ascend_heightfield/attribwrangle3/attribvop1'.

    I don't really know why it happened and when I checked for it on the sideFX forum and on Odforce, I didn't really find anything .

    I'm pretty new to this but I'd really like to improve my vex, and your explanations are really clear. I hope I'll be able to follow the other classes !

    • animatrix_ 2 years, 2 months ago  | 

      Hi, that sounds like a compile error. Can you share your scene please?

  • NicTanghe 1 month ago  | 

    Hello it seems that xyzdist doesnt work like this in houdini 19.5 anymore.

    They seem to always return -1 and 0,0

Please log in to leave a comment.