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hello me again curios as always:P i've been wondering how to "load" a velocity of a spawned circle.

example: When a circle spawns it should be moving with a velocity of 10m/s and a box tells it which angle it should be "velocifyed" at;P

Thank you for helping me learning this:P
//rideg

When spawning it use vel := [x, y]. x is how fast the object will move left or right in meters a second. y is how fast the object will move up or down in meters a second.

Thanks but how do you replace "x" and"y" with something like scene.my.angelvelocity?

Calculate scene.my.angelvelocity and then in the velocity put [scene.my.angelvelocity(0), scene.my.angelvelocity(1)].

I meant something like vel:=[300 * cos(scene.my.angvelocity), 300 * (scene.my.angvelocity).

Scene.my.angvelocity is the angle of the box that the spawner is attached to and I can't figure it out how to connect the variable to the box.

Oh. Thanks for telling me that. To convert the angle of the box into speed you want to spawn you can use e.normal or cosine and sine. vel := e.normal * 300 or vel := [300 * math.cos(scene.my.anglevelocity), 300 * math.sin(scene.my.anglevelocity)]

Are you trying to make a gun with adjustable power?

Could I have an example code please? didn't fully understand..

Converting a scalar velocity, a speed with magnitude but no direction such as 15 m/s, requires a bit of knowledge in trigonometry. Looking at your post, I can see that you suggested 300 to be the constant scalar. Assuming you have found the angle, we can now calculate it. I will make a function for this so it will be easy to modify.

Code: Select all

Scene.my.speed=(v, a)=>{[v * math.cos(a), v * math.sin(a)]

v is the velocity that you will use as a constant
a is the angle, in radians, of the gun

Scene.my.speed(15, math.pi/4) will give you [10.606602, 10.606602]

You can use that to spawn a circle with the preset velocity. vel := scene.my.speed(15, scene.my.angle)

ok thanks

Btw [a*x, a*y] = a*[x,y]
this can slim down some code. it's not important, i just wanted to mention^^

so for this example:
[v * math.cos(a), v * math.sin(a)] is the same as v * [math.cos(a), math.sin(a)]

I can't get this to work:( maybe I should do smaller stuff, Can't figure it out how it works(yet!).

Can you please post what you currently have? It would really help if I knew what I have to work with here.

sure wait some minutes:P

[scene]35064[/scene]
here you go thank you ALOT if you can make a simple code so I can understand this.

I will take a look at it in about half an hour.

The biggest problem that the scene centers around is this.angle. The easiest fix to this is instead of spawning the circles with vel := [100 * math.cos(scene.my.angle), 100 * math.sin(scene.my.angle)] I would suggest using vel := e.normal * 100.

what does e.normal mean??

e.normal is the normal of the collision event
http://en.wikipedia.org/wiki/Surface_normal

So you don't need to bother about the angle anymore.

but that doesn't give the angle the spawned circle chould be velocifyed at, does it?

Got it now thanks alot for the help!

e.normal is a vector. the angle is already in it

and then I typed a script: (vel:=100*scene.my.angle) scene.my.angle = e.normal of the event were the laser hits it! thank you