fex Posted May 21, 2004 Share Posted May 21, 2004 hi all, does anybody has an idea how to get rid of those superfast particle rotations? This happens with wind, noise, attractors..; even if they have low amplitudes particles tend to flip, rotate fast and not related to the translation speed. Tried all Pops relatated to rotation; thought angular vel. drag could do this but it says "missing rotation or angular vel. or torque"... i only want to make rotational speed smoother Plzzz help!! Thanks to all reading this fex Quote Link to comment Share on other sites More sharing options...
Henster Posted May 25, 2004 Share Posted May 25, 2004 Hi fex, Superfast particle rotations? Prehaps there is some part of your network playing up unexpectedly. Try using the Instance Pop. Copy on something simple, like a box, and bypass different parts of the network to isolate where its going weird. or, sloppy trig. ?? Good luck H Quote Link to comment Share on other sites More sharing options...
fex Posted May 25, 2004 Author Share Posted May 25, 2004 hi henster and all others, its not a problem of instancing...you could see even by activating particle axis. I know which force a causing it (wind in different directions changing fast). Its not directly rotation its more like the normals of the particles change too fast or flip suddenly and a copy sop with rotate to normal on is creating this "rotation". Anyway its in the simulation ... i had this problem with attractors and slowly growing attraction too. Is there nobody who had something similar or is it my fault still very intrested in feedback thx fex Quote Link to comment Share on other sites More sharing options...
Lukich Posted May 26, 2004 Share Posted May 26, 2004 you can try and import the translation values and the normal values from sops into chops, apply a filter chop to them and output them back. that can help you get rid of the abrupt turns. good luck! Quote Link to comment Share on other sites More sharing options...
old school Posted May 27, 2004 Share Posted May 27, 2004 The problem with flipping particles is when the velocity changes rapidly and how it affects each particle's own local axis (local frame of reference). You need to control the flipping with POPs that control the particles local axis. Some are the lookat POP, rotate POP, upvector POP. In the display options, you can turn on the local axis button at the lower right of the first folder. If you have a particle primtive in your viewer, each point will now have a little xyz axis displayed. If you can't see them because they are too small or too big, go to the last folder in the display options and scale the normal scale slider to adjust. In POPs, if you don't use a rotate POP or an upvector POP, the local frame of reference is built from the velocity and a default global up-vector. The velocity builds the Z-axis, the upvector defines the Y-axis and the X axis is then build using a cross-product operation. Quote Link to comment Share on other sites More sharing options...
old school Posted May 27, 2004 Share Posted May 27, 2004 The particles then use the local frame of reference to orientate the instance geometry to the particle. The copy SOP also inherits this local frame of reference when copying geometry to the particles. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.