Physics RK4 001
Over here http://gafferongames.com/game-physics/integration-basics/
someone shows how to implement physics simulations using an RK4 integrator
and here’s my implementation of his c++ source as a Daz Script
1 - create a cylinder, 30cm tall 1 cm diameter
2 - select the cylinder
3 - run the script
the Z rotation angle of the selected cylinder will be driven by the simulated output ( x )
the line that reads “if( (cpt++) > 200 ) break;” is a safety device limiting the simulation to 200 frames
cpt also serves as the keyframe time
you may want to replace
zRot.setValue( cpt * tick, state[0] );
by
zRot.setValue( t * 4800, state[0] );
g_k is the Hooke’s law spring constant, g_b is the dampening factor
and here is HTML5 applet to display the curve and motion