I’ll add a couple more things.
Both Houdini and TD are what you call procedural programming environments. You hear this term bandied about a lot, like, in No Man’s Sky planets being ‘procedurally generated’. It’s an interesting term, which I think can get somewhat confused with the term ‘generative’, but ultimately, procedural is just a different programming type, which if u really broke it down can simply mean ‘cause and effect’.
This means an artist creates a chain, or in TD, a ‘network’, and really, net results are the product of what comes before, so changing a node in the chain changes the final output.
This is quite simple, and artist-friendly, if you like. As opposed to say, object oriented programming, where one creates sets of variables, objects, arrays, classes and their associated methods, and then ‘calls’ the objects in question to display based on the input method data. TD still uses these sorts of programmatic elements, such as a data lists, but again in this mapped out procedural way.
I should say I’m a newb, I might not be describing the above in the most accurate way but it’s the point in describing the differences. Likewise, node-based, or visual programming as opposed to text-based.
I personally find TD to be extremely taxing on the mind. It’s possibly just the way I’m wired, and I’ve always felt similarly about max. But there’s an aspect to that procedural generation which can really balloon out - such that I personally begin to feel like a ‘processor’, keeping track of all the settings, digging in to parameter boxes to see what is set, and what is going where. Oddly, visual programming languages are supposed to be more suited to artists, but I always found something like Processing to make much more sense and be more logical.
However TD’s advanatage there is giving you way more bang for your buck, and higher fidelity, for less programmatic or algebraic knowledge as you would require in C++ or Java.
Lately I’ve found Notch to be quite a useable visual based node software. There’s less code-based snippet requirements (if any), enough flexibility built into the system that you can gravitate towards your own style, and it can give you much of that VFX style simulation results but perhaps being even less cognitively demanding than TD. Notch’s only real barrier to entry though is it’s pricing (if you want hi res results), because it seems more geared to the pro touring market, than say the indie AV scene.