Accelerated motion

[Lenticularis]

Is there a simple solution to implement accelerated motion in Vizard?

Or do I have to use the normal vizact.move function and combine it with the formula "v = a · t + v"?

Any ideas?

[Jeff]

Are you moving the viewpoint or some objects? Can you describe a bit the application you are creating?

[Lenticulariss]

Objects. I want to move an object (let's say a car) forward for a certain duration and with a certain average velocity. But with accelerated movement, not with constant velocity.

Example: vizact.move(0,0,6, velocity)
--> In this function I can define the direction of movement and the duration of the movement, I can also specify a certain velocity. But now I want to accelerate this movement by let's say 1 m/s^2 (so that the velocity is rising for the specified amount of time)

[Lenticularis]

Moving an object.
Vizact.move(0,0,velocity,time) --> I can indicate a velocity and a duration of the movement. How to implement accelerated movement?

[Jeff]

You could apply a force (http://docs.worldviz.com/vizard/#Forces.htm) using physics or register a function with vizact.onupdate (http://docs.worldviz.com/vizard/#commands/vizact/onupdate.htm) where the object's position is set each frame.

[Lenticularis]

I tried the following code. Do you see mistakes?

def Movement():

Object.setPosition(0,0,0)

v0 = 0
t = 0
a = 1

while t < time:

s = v0*t + 0.5*a*t**2
vizact.ontimer2(0.1,0,Object.setPosition,0,0,s)
t = t+0.1

I was not really expecting it to work since it was only a "quick and dirty" solution. But I actually don't see where the problem is.

[Lenticularis]

Never mind. Managed to do it with an even simpler solution. It is not entirely precise, but it works quite well. It isn't even shaking. Here is the code I used:

def Movement():

Object.setPosition(0,0,0)

v0 = 0
t = 0
a = 5

while t < time:

s = v0*t + 0.5*a*t**2
Object.setPosition(0,0,s)
t = t+0.0168 #Adjustement based on processing speed of computer (lazy amateur workaround)