Show speeds in text (question)

[Thooto]

Hello, I need your help!

I'd like that, in the text of a box, we could see the speed of an object.

Example : I spawn two boxes, one of them with the text "Speed = xxx m/s". If I drag the other box, in the velocities of this one, you'll see an xxx m/s. I'd like to see the same speed in the box with the text.

Could you help me? What do I have to write?

Thanks! (Sorry if I don't explain myself well...)

[bozbez]

How i would do it is... Get kilinich's k-probe laser edition, stick it on the object you want to measure the velocity of, get the box you want to read the text of, and put a laser with maxrays 0 on it, and make it semi-transparent (the box) and in the lasers' onlaser hit put:

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(e)=>{e.geom.text = "'" + (scene.my.k1vel(0) + scene.my.k1vel(1)) + "'"}

Of course there are other ways, but i don't know where you're going to use it.

[Thooto]

Thank you it works! But it will be great if there was something more simple!

But maybe if I create a simple scene, you'll understand what I want.

[Someone Else]

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textureMatrix=[e.pos(0)-textureMatrix(2), e.pos(1)-textureMatrix(3), e.pos(0), e.pos(1),(textureMatrix(0)^2+textureMatrix(1)^2)^0.5, 0.0, 0.0, 0.0, 0.0];


Credit to davidz40 for this code. I did modify it a bit.

Anyway, put an alternating collider (let me know if you don't know what that is) on the second box. In that box's onCollide, put the above velocity code, followed by the following:

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scene.my.speed = textureMatrix(4) * 50

First, you will have to declare scene.my.speed = 0 in the console (F11).

Then, in the first box, in the script menu, in the text space, put {"" + scene.my.speed}.

That's how I would do it.

[Thooto]

Ok thanks I'll try this. And, yes, I don't know what an alternating collider is... Could you explain me?

Edit : I found another way with laser, etc...Now it works, with the codes you gave me! Thank you!

[Someone Else]

An alternating collider is better than a laser for this application, for it gives exactly 50Hz.

Okay.

Make two boxes, with some space in between.
Put a circle between the boxes, overlapping both, but only a bit. More overlap means more shock resistance, but also more vibration.

Fixate the boxes to the background, center hinge the circle.

In the Collision menu for all three parts, check the No Self Collision box. This will in the future be referred to as putting the parts on heteroCollide.

Make one of the boxes not collide with water.

In the onCollide of the circle, put this code:

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collideWater = ! collideWater

This has the effect of making the circle collide with one of the boxes. During that collision, the circle changes its collideWater, which in turn makes it collide with the other box, where the precess repeats. Hence, "alternating collider".

[Thooto]

Ok thanks! I think I've understand the system. In fact, that's a refreshing system of the position, it calculates the difference of position into the two times where it's collided, then it converts it to a speed. Am I right?

[bozbez]

Mmmm.

[Someone Else]

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textureMatrix=[Difference between current horizontal pos and previous horizontal pos, proportional to the horizontal velocity in m/s,

Same as textureMatrix(0), but vertical,

Previous horizontal pos,

Previous vertical pos,

Speed generated from what some consider the single most famous equation of all-time, that of Pythagoras,

placeholder,

placeholder,

placeholder,

placeholder]


[SyntaxError]

Thats my "get speed script":

- scene.my.speed_box1 returns the actual speed of the object in m/s. You have to point with a laser on it
- scene.my.speed_kmh_box1 returns the actual speed in km/s
- timed and posd are the differences of time and position to the last measurement. Then simply v=ds/dt

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(e)=>{
    scene.my.timed_box1 = app.time - scene.my.time_box1;
    scene.my.posd_box1 = scene.my.posx_box1 - e.pos(0);
    scene.my.speed_box1 = scene.my.posd_box1 / scene.my.timed_box1;
    scene.my.speed_kmh_box1 = scene.my.speed_box1 * 3.6;
    scene.my.time_box1 = app.time;
    scene.my.posx_box1 = e.pos(0);
}


[Someone Else]

App.time does not do anything. Instead, you want sim.time or system.time. Sim.time is how long the simulation has been running (in seconds), system.time is how ling the application has been running.

[SyntaxError]

app.time = sim.time

just try it!