Nerd Rant: DOPs

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Part of: Nerd Rant
Nerd Rant

Recorded back in October when Mo was cranky due to reasons, Manu decided to discuss his (then) favorite topic when it comes to Houdini: DOPs. Turns out it is not so much Mo’s favorite topic. Watch this nerd rant to see us being cranky and stupid about dynamics in Houdini.

Not really much more to say honestly. Except that Mo’s attitude changed a bit since the introduction of Vellum. Which we couldn’t discuss when we recorded this rant. (Admittedly we’re slow when it comes to editing.)

Have fun! 🙂

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  1. Great rant… I love how we all came at the same conclusion in the end!

    Another thing to add to this rant, is constraint networks get imported in as geometry, but they don’t update like the sim geometry (they instantly turn to data – purple stream!). You can write your sopSolver to re-output an updated constraint network, but feels like its something that *could be done a little better behind the scenes, if we are really just updating point positions. To really be able to access any of this data at SOP level would seem to make sense.

    But computation speed is always of top importance with this type of work…maybe the DOP pre-compiled blocks are faster.

  2. Haha, interesting watch! I do think it’s really funny that you are doing these crazy and fairly complex things in SOP, and at the same time think DOPs is the complex part 😀
    I do agree it seems convoluted and hard to grasp at first, but I think for me I had to drop the idea of thinking about it as a linear execution flow, then it was ok. It was also a big eye-opener when I realized, for example, each POP source and any nodes connected in the same thread below only processes that source. You can then merge different sources together and merge in forces below from a separate thread. Giving you both a global and per source dependent flow.

  3. I think one of the problems with DOPs is also the help files, while they are concise and helpful for SOPs nodes, the format is unhelpful for understanding how DOPs works. In a similar fashion, SideFX did a great job of updating the Mantra help files to make rendering very accessible a few years ago.

  4. SideFX guys have said, if we get we should get rid of a context it would be SOPS actually, haha

    DOPs is good, you don’t have to do Houdini as OTHER apps, because it becomes a closed thing like other apps.

  5. I think the power of houdini do lies in that its simulation engines are very open allowing you to customize and speed up your sims as much as you want. It will be possible however to bring the DOP workflow into the SOP network. But it will require a node relationship that allows the looping feedback innate in DOPS so your tree in SOP will become quite complex. The only part that I find confusing of the current system is when I have to manipulate data of a simulated geometry within DOPS (as when you breack constraint according to their length while the RBD is running). Basically a SOP solver WITHIN a DOP solver. I feel that could be polished by bringing everything into the DOP environment.

  6. Robert Kelly

    I really needed to hear this! its confusing but this gives an overview of all the parts.

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