Simple Character Rig With Blendshapes

[Gurbo]

Hello,

I put a pretty clunky rig together for my coffee cup 'Cuppa Joe'. I started setting some keyframes on it - just to test it out. Please have a look and check it out!

Couple of tiny questions..

Does Houdini have any onion skinning feature that can show previous keyframe poses or a trajectory?

I still have to apply a POP network to get some steam and fluid. Not sure if I should put the emitter out the spout or inside to get some particles colliding and sliding.

Gurbo

cuppa_joe04j_animjump.zip

[edward]

It's a nice simple character. It's my type of rig. The only thing I found a bit weird was picking the frame of the face controls which had it's pivot at the bottom of the character instead of somewhere on the frame itself. I also expected the face control circle to be parented underneath the frame so that when I moved it, the circle would follow along.

There's no exact onion skinning in Houdini per se. However, you can take a new camera object and on the OpenGL tab of its parameters, change the Clear Viewport parameter from 1 to something lower like 0.5. Now look through this camera in the viewport. Now when you scrub, it will only partially erase (for 0.5, this means half) of the viewport before drawing the next frame. In this fashion, you can observe the arcs on your character. To actually clear the viewport again though, you need to set the Clear Viewport parameter to 1. To speed this up, you could set up a F-key alias.

To plot the motion of an object over time, you can use the Motion Trail HDA from the Houdini Exchange (link). It will generate a curve by taking the position of the object at each frame. It might slow though so your mileage will vary.

There is also the "Snapshot" memory feature in the "memory controls" toolbar at the bottom of the viewer underneath the one that has the camera menu. This is more of a tool for timing though. What it does is allow you to take a picture snapshot of your viewport and assign it to a memory button. One can then attach hotkeys (eg. 1, 2, 3, 4, etc) to quickly flip between the display of these images. So say you're working at frame 12 and have prev/next keys at 8 and 16. If you saved the snapshots at frames 8 (key 1) and 16 (key 2), you can quickly flip between the 3 poses by tapping the 1 key, wait, tap the 2 key . So now you adjust the pose at frame 12 again, tap the keys until you figure out what you want, adjust the pose, tap tap again, etc. It sounds complicated but maybe you'll like it. This feature came at the request of a veteran animator.

[Gurbo]

Hey, thanks Edward,

I'm honored that you took the time to check it out. I see what you mean about the lipsync controls. I was using a subnet instead of parenting and I need to adjust the pivots.

Thanks very much for the suggestions for onion skinning. Jason's motion trail HDA is pretty cool. It was a good opportunity to become familiar with Digital Assets. Tinkering with the Open GL tab on a new camera was fun and along the way I learnt about the memory controls and how to set up hot keys.

I learnt a lot today!

Gurbo

[Crusty]

Hello,

I still have to apply a POP network to get some steam and fluid. Not sure if I should put the emitter out the spout or inside to get some particles colliding and sliding.

I would create a Group sop after the Deform and group out the points at the lid opening. I would then create another object and Object Merge that group, and append a Pop Network.

If this is the animation you will be using, you will probably have to raise the Oversampling to account for the quick motion.

Just my two bits :-)

[edward]

Well, if you're going to create groups, create them *before* the Deform SOP so that it doesn't have to cook every frame.

[Crusty]

Well, if you're going to create groups, create them *before* the Deform SOP so that it doesn't have to cook every frame.

23300[/snapback]

That's what I was thinking after I post the reply ;-)

[Gurbo]

Well, if you're going to create groups, create them *before* the Deform SOP so that it doesn't have to cook every frame.

23300[/snapback]

I never would have thought of that,

Thanks very much fellas.

If I were to do fluids, say, coffee spilling over the lip, would I use particles linked to metaballs? I've only mucked around with particles when I was watching some 3D Buzz tutorials. In other packages I wouldn't consider it.

[deecue]

yea, you could do the metaball thing.. could also look in to using sprites if you only have one machine to be working on.. also, render in layers.. it will save you so much time and you will be able to achieve much better results in the comping stage..