Help with script?

[Rideg]

Hello, can someone tell me why this script ain't working. It is supossed to spawn a box that is pointed towards the activated laser. Instead it spawnes with that angle - or + 90 degrees. Here's the code:

Code: Select all

(e)=>{
    Scene.addBox({
        color := [0.42, 0.42, 0.42, 1.0];
        onCollide := (e)=>{e.this.collideSet = 32};
        heteroCollide := true;
        friction := 1.0;
        drawBorder := true;
        airFrictionMult := 0.0;
        density := 10.0;
        collideSet := 64;
        zDepth := +inf;
        pos := e.pos;
        angle := math.atan(e.normal(1) / (e.normal(0) + 1)) * 2;
        size := [0.085, 0.6]
    })
}

[gradyfitz]

Hello, can someone tell me why this script ain't working. It is supossed to spawn a box that is pointed towards the activated laser. Instead it spawnes with that angle - or + 90 degrees. Here's the code:

Code: Select all

(e)=>{
    Scene.addBox({
        color := [0.42, 0.42, 0.42, 1.0];
        onCollide := (e)=>{e.this.collideSet = 32};
        heteroCollide := true;
        friction := 1.0;
        drawBorder := true;
        airFrictionMult := 0.0;
        density := 10.0;
        collideSet := 64;
        zDepth := +inf;
        pos := e.pos;
        angle := math.atan(e.normal(1) / (e.normal(0) + 1)) * 2;
        size := [0.085, 0.6]
    })
}

This is a side effect of the fact that a/b = -a/-b, so when you call the inverse tangent function with the value you have given, it's difficult to differentiate two positive values from two negative values.

There is a thread with a function - atan2, which takes both points (in an array) and returns a value in radians, Some extra math functions.
(atan2 function by standardtoaster)

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Scene.my.atan2=(P)=>{2 * math.atan(P(1) / (((P(0) ^ 2 + P(1) ^ 2) ^ 0.5) + P(0)))}

The function can simply be used by putting in:

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Scene.my.atan2(e.normal)

Or if you need to modify the normal:

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Scene.my.atan2([e.normal(0) + x, e.normal(1) + y])

(where x and y are any numbers, just for demonstration)

To change this to point to the laser, you would probably be better off getting both points and working out the angle between them.

Hopefully this helped .

[Rideg]

That has to be the best answer I can get. Thank you alot, well explained