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Preventing "zombie fish"? A question about stretched particles.
Hi folks,
I'm trying to use a particle system to create a school of fish. I have a nice uv animation of a swimming fish. I have the particle emitter set to give the fish a local velocity in the x axis, and the particle animator set to create a local rotation around the y axis. I have the Particle renderer set to "Stretched", so that the fish particles face their direction of movement. This gives a very nice impression of a school of fish swimming in a circle. My fish animation is facing left. Whenever the fish are swimming left relative to the camera, they look fine. Whenever they swim right however, they flip upside down, and look like dead "zombie fish". Is there any way to get the Stretched particle renderer to mirror the particle when the particle is moving right, rather than rotating it 180 degrees?
Thanks,
-matt
Answer by Waz · Sep 02, 2011 at 10:18 PM
No, not possible. But you could use two particle emitters - one for each direction. Shouldn't the fish be appearing from the sides or such anyway, not from a point?
The fish "appear" all at once from a one shot particle emmitter, then swim in a circle around their emission point. There is heavy fog in the underwater scene, so you don't see them appear out of nowhere when the emitter is triggered. Appearing from both sides isn't really an option as I can't get the fish to move as in a convincing school that way. I still haven't solved the upside down issue, but have mitigated it somewhat simply by having them swim counter clockwise ins$$anonymous$$d of clockwise. This means when you are within the school, and seeing the fish up close, they are more likely to be right side up. When they you are outside the school, they still appear upside down when moving to the right, but you are usually farther away so it isn't as obvious. Its interesting, watching the particle squares in the scene viewer, they appear to stretch then mirror vertically as they change direction. Its too bad they can't mirror horizontally ins$$anonymous$$d. It seems like it would make more sense.
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