Particles inside a mesh

I’m working on modelling an hourglass and I have my hourglass shape and it all modeled. I can’t seem to figure out how to get the particles inside the glass. Course I’m also not sure if the particle system would be the best choice for this as I haven’t worked with it much at all. Going though the forum there was also talk of the fluid simulator but that doesn’t make sense to me since sand isn’t a liquid.

I’m going to be rendering it out in cycles once it’s completely done if that’s information that anyone needs for this.

Any help or point me to a tutorial would be greatly appreciated.

the problem is generating hundreds of thousands of sand particles which will require crazy computing power.

Ah that’s what I was afraid of. I did try with like 1000 little icospheres but they decided that they wanted to be both inside and outside the mesh. So I’ll just leave it empty. Or if it should be a mesh inside there that has a sand texture uv mapped to it. That might work out better in the long run since I’m not looking to animate it or anything like that.

Thanks :slight_smile:

You could use the best of both worlds… Model the sand at the top of the hour glass as a mesh, then set a vertex group at the bottom of the mesh to emit your particles. Set the bottom of the hourglass as a collision object for these particles. One thing that’s popping to mind is that you’d want to animate the top sand so that it’s draining down over time. Could try animating between a couple of shape keys…

Shape keys are something I haven’t looked into yet as far as animation goes. I’ll look into that more once I get my issues with UV taken care of.

Thank you all for the information I appreciate it.

No problem, when you get a bit of time, here’s a tutorial on them, I found it pretty useful:

Here is an example using particles and the fluid system together. This is an old 2.49 file that tried in 2.6.2 r45774 that worked. I recommend pulling down a build from with OpenMP enabled, such as the one I mentioned. This speeds up bake times quite a bit. To get the most out of this file you will need to increase the resolution of the fluid. The resolution of the fluid in this posted image is 65, which is just above preview.


26_sand_hour_glass_249.blend (332 KB)

Thanks. I’ll take a look at that tutorial and the blend file later on this evening when I have spare time. Not sure if OpenMP will work for me since I’m only on a dual processor so I probably won’t see much of a speed up time…or will I?

I shoulda came here a long time ago learning a heck of a lot more than when I was trying to do this on my own.

Always good to share, I popped on here to ask a question about why my mac was only using one processor thread to bake a simulation, so while waiting for an answer thought I’d share what I know. Still haven’t had an answer to my question, but I’m happy knowing that I might have helped someone out a bit.

Would be great to see your finished piece…

That is what the OpenMP (Multi-Processor) build is about. Using multiple processors for baking simulations. It does not use all of my CPUs on my quad, but it is faster than the single core official Blender version.

Here’s something I put together this morning using the method I described.

I made the bottom expand simply by keyframing the size of a simple object at the bottom of the hourglass. Composite this nicely, bit of vector blur, maybe render with cycles using a glass material and it should look nice.

Be sure to bake the particle simulation before animating/exporting…

hourglass.blend (1.95 MB)

Hi Atom, thanks for the reply. Don’t want to hi-jack this thread, but thanks for the advice. Have heard of Open-MP in trying to sort out my issue, but knowing that it’s there hasn’t helped, still slow baking. Never mind, no big problem…

Thanks again. I’m going to get back to it once I can get some free time my schedule’s been hectic lately.