Algodoo

I don't understand, isn't this just 2 mouse controlled arms?

If you don't understand... who will?

Key feature is how fast it work. If you ever try build mouse controlled pointer, you must face that problem. RaRa found great solution - use materialVelocity instead of motor hinge.

i've used materialvelocity as a method to point to things before, but indirectly(using air friction).

I can't see any difference by looking at them, but I can see by plotting position that the hinge has more overshoot and takes longer to get to position. Nice demonstration.

@Dare
the upper pointer adjusts the materialVelocity of the circle, which collides with the surrounding box, resulting in the circle turning.
seeming the pointer and laser are attached to the circle, they turn with it, and the laser gets new variables to work with..

the lower pointer works the same way, but now adjusting the motor speed of a hinge, that is attached to the pointer and the background.

result:
the upper one is faster, and more stable when you set the sim speed to 10 (known to some as sim.timefactor).

btw, if you don't know what materialVelocity does, start experimenting with it, for example, on a circle or box that is laying on a plane


@Kilinich
if I made some misakes in that explanation, please say so.

how does the green one work

dude, in the material velocity one, i just figured out how to get rid of that wobble whe the mouse goes too close to the laser where it hits,
(e)=>{e.geom.materialVelocity = +(2 * (e.normal(1) * (app.mousepos(0) - e.pos(0)) - e.normal(0) * (app.mousepos(1) - e.pos(1))) / (((app.mousepos(0) - e.pos(0)) ^ 2 + (app.mousepos(1) - e.pos(1)) ^ 2) ^ 0.5))}
instead of
(e)=>{e.geom.material velocity = -(2 * (e.normal(1) * (app.mousepos(0) - e.pos(0)) - e.normal(0) * (app.mousepos(1) - e.pos(1))) / (((app.mousepos(0) - e.pos(0)) ^ 2 + (app.mousepos(1) - e.pos(1)) ^ 2) ^ 0.5))}

The blue one seems to have slightly stiffer control. Maybe some derivative gain in the loop?