Algodoo

Yes. Good idea. I updated (2) of my tutorial scenes by using your idea with modified code so they will work with the mouse or arrow keys.

The Linkage,

Regarding "animated, smoother feel", I had totally missed the point, but now that I see it, I like it. Not that it matters much, but I suggest gluing the base circle to the background, turning off gravity, and letting users know they can adjust the hinge constant to vary the response time.

Kilinich,

Good work. Fun for all ages.

Xray,

There already is key that will erase the entire pattern and start a new one. It's called the Undo button.

P.S. Changed my thinking. If an erase button saves one click and there are thousands of uploads and each person draws multiple snowflakes, then an erase button could save thousands of touches, key-presses, or mouse clicks.

Xray,OK.

Nice use of steam, punk.

Good.

I used to hear stories of kids making it all the way over the swing. I was a little disappointed to find out that can't be done on a rope or chain swing.

Regarding "rock will slowly move and tip over", Xray and The Linkage knew about that. Feel free to balance the rocks so they stay balanced indefinitely and post the scene as a response.

Yes, yours is good. I was the one who gave it the up rating.

Q: Why does the damper move so far from the building center?
A: Nothing in the scene is the correct scale.

Nice construction and presentation. Sim frequency should be at least 200 Hz for smooth operation at 180 rad/sec (1700 RPM).

Nice work. I need a little more practice before I post my score.

P.S. 300

Setting the gray frame inertiaMultiplier to +inf will accomplish the same result as the stretched hinge.

The general solution turned out more complex than I expected:

a := math.atan2(((w3 / 2 + c1 * w4) / ((w3 + w4) / (cos(B) + u2 * sin(B) + (sin(B) - u2 * cos(B)) / u1)) - u2 * sin(B) - cos(B)), ((w3 + w4) * (h / (2 * L)) / ((w3 + w4) / (cos(B) + u2 * sin(B) + (sin(B) - u2 * cos(B)) / u1)) - u2 * cos(B) + sin(B)));

If you know of a simpler solution, then please let me know. Actually the simplest solution may be to just draw it in Algodoo and then let Algodoo figure it out.

Thanks Xray,

The problem was math.toInt(+inf). Speaking of friction, I noticed that if the horizontal and inclined boxes are glued to the background, then the friction forces differ from the forces on the same boxes when they are double hinged to the background. When the boxes are glued to the background, then the sum of the forces in the x (or y) direction do not equal to zero, which they should.

This cool scene is a gas. I bet you were under some pressure when you made it.

Your "Clear Tracers" button does not work. Use the following or fix it some other way.

in console:
scene.my.pens := []

in tracer onSpawn:
scene.my.pens = scene.my.pens ++ [entityID]

in button onClick:
ra := [];
n := string.length(scene.my.pens);
scene.my.xFor(0, n-1, (i)=>{
thispen := scene.entitybyID(scene.my.pens(i));
newpen := Scene.cloneEntityTo(thispen, thispen.pos);
scene.removeEntity(thispen);
ra = ra ++ [newpen.entityID];
});
scene.my.pens = ra;

Save and then open the scene for the changes to take effect.

Look ma, no description.

This was a real nail biter. Spoiler alert! I thought Jack might get blown up at the end.

Looking good. I suggest hiding water boxes and enabling ratings.

Nice work. One suggestion is to set the brown grid boxes to 10% transparency in order to put more emphasis on the moving elements.

Nice presentation and operation.

Here's another way of doing the code, it's just FYI since your code works fine:

e.other._type != e.this._type ? {
_win = rand.uniform01;
e.this._win > e.other._win ? {
eval("scene.my.type" + _type + " = scene.my.type" + _type + " + 1");
eval("scene.my.type" + e.other._type + " = scene.my.type" + e.other._type + " - 1");
e.other._type = e.this._type;
e.other.color = e.this.color
} : {}
} : {}

Thanks.

Smoking!

It's like automatically changing the pivot point of a see saw to accommodate the weight of the riders. I suspect that the pulley mechanism is doing some work since the change in potential energy of the right spring is greater than the force times distance on the left rope.

S: When I ... ignore the changing mechanism.
R: Don't do that.

S: The pivot point remains exactly in the center.
R: While it's true that the pulley rotates about its center, the hinge that balances the left and right forces moves horizontally with respect to the ground.

The scene employs two robot arms, one arm is attached to ground and positions the pivot hinge to balance the right and left forces. The other arm is attached to the pulley and maintains the pulley location. The two arms are connected to each other with a freely rotating hinge.

Hopefully the explanation above helps out. If not, then you might be out of luck because I'm not sure if I understand it completely.

Other users should feel free to offer an explanation.

Good explanation. I couldn't have said it better.

Suggestion: Make the scene so it starts all the way zoomed out as opposed to all the way zoomed in.

Details:
I was playing with this and noticed that it generates 6X faster when zoomed all the way out vs. all the way in. My suggestion would be to zoom all the way out (zoom = 0.01) and run the scene until the boxes start to become visible and then stop and save the scene. This way the new scene will appear to generate 15X faster and then the user can zoom in as opposed to zoom out.

Thanks for the compliment and verifying the bug. Now I know that it is not just screwing up on my machine.

Thanks.