Lately I got a problem, which I couldn’t figure out how to solve:
I want to animate Bloodcells following a Path. This would be really easy using a Particle System and a Curve Guide.
BUT: They have to show some pumping-like Behaviour. Not using a Curve Guide I would simply animate the Evaluation Time for any other Object than a Particle System.
In 2.49 their was Time-IPO available, which was replaced by the Evaluation Time I think.
Just can’t figure out how to do this kind of Stuff nowadays.
There is a new routing system in 2.6 for particles. For instance, you can assign a texture to control time.
I have yet to see this feature work, but I have setup the basic flow in the attached BLEND. Everytime I assign a noise based material to control time nothing happens, but in theory it should work.
By assigning the texture to control density, that seems to work for sure. So with two different particle systems with different velocity normals you can at least emulate the clumping of blood cells. Perhaps you can just animate the blood vessel wall to pulse and that might be enough for your project?
In 2.49 their was Time-IPO available, which was replaced by the Evaluation Time I think.
Just can’t figure out how to do this kind of Stuff nowadays.
Unfortunately I don’t think you can do this sort of thing nowadays. I would be pleased to hear otherwise but I have not found a way to alter particle speed along a Curve Guide. I think you would be better off to use a Lattice to control the direction of the particles instead of a Curve Guide. If you already have the curve guide to control particles direction you could disable the Physics and use it as a curve modifier to control the shape of the lattice. Then you could use Atom’s method for controlling the speed etc or you add a Wind force field and keyframe its strength.
