Scratch

Project Notes

Bouncing Balls with Soundcolors is a much enlarged version of: (link to project) by Canthiar You now have colors an sounds and many parameters to play with: Up / Down = -/+ Gravity Left / Right = -/+ Emitter Speed B / A = -/+ more Balls 1 = switch Edges 2 = switch Turn Effect 3 = switch Random 4 = switch Drawing 5 = switch Sound Space = start Balls again DragDrop Collision Objects DragDrop Balls DragDrop Emitter Turn Emitter by pulling it's tip H = Help (english) G = Help (german) R = Start/stop emitter rotation Chantiers original description: You can move the object emitter around with the mouse and change the direction by clicking on the pointed end. This is what I consider a production version since I've inlined a few things. I have a more academic version that is a little easier to read. The whole thing is also dumbed down a little to make the math a little easier. How it works: When a ball encounters a collision object it uses the [ point towards[ Collision ] ] command block and then uses sin and cos to calculate a colliion normal. That normal is used to calculate a resulting velocity perpendicular to the surface and velocity tangent to the surface. Friction and restitution are applied to make the ball bounce. Added a spin feature.