J U M P

[Floof]

Hi everyone !

 

I am currently working on this Babylonjs level http://www.peru-lab.com/quetzal/bishop

And I would like to add a jump fonction for the player, using the left mouse click for example.

 

Can you help me please ?

 

 

[Dinkelborg]

You should integrate a physics plugin like Oimo.js (if you downloaded Babylon from GitHub you have it already)
This will allow you to create physics impostors for your objects, in your HTML file you will have to add something like: <script src="js/your_subfolder/Oimo.js"></script>
Then inside of your Javascript you have to add:

scene.enablePhysics(new BABYLON.Vector3(0, -20, 0), new BABYLON.OimoJSPlugin());

at your create scene funcion and now for ever Object that should be influenced by gravity (like your camera or any mesh) you have to create a physics impostor like this:

bouncy_ball.setPhysicsState({ impostor: BABYLON.PhysicsEngine.SphereImpostor, mass: 1 });

It will immediately have physics and collide with other objects that have an impostor, if you set mass to 0 the object will still have physics and be able to collide with others, but it will be static (so not infected by gravity).

 

finally, to make your object jump, you can give it an impulse, if it has an impostor, like this:

var force_vector = new BABYLON.Vector3(0, 20, 0);        bouncy_ball.applyImpulse(force_vector,bouncy_ball.position);

One other tip: if you want to move your object by code, so for example let's say you have a character controller class and you try something like:

var onKeyDown_A = function(){player.position.x -= 0.1;}

this won't work if a physics impostor is controlling your object, but you can temporarily deactivate the impostor like this:

var onKeyDown_A = function(){    player.setPhysicsState(BABYLON.PhysicsEngine.NoImpostor);    player.position.x -= 0.1;    player.setPhysicsState({ impostor: BABYLON.PhysicsEngine.SphereImpostor, mass: 1 });}

[Floof]

thanks for your answer.

It seems that it's only working on meshes.

With the camera object, it's not possible to call setPhysicsState, with the camera object, which method should I call to apply a physical state? (I'm trying to do a FPS sort of level where the player can jump). Thanks

[Dinkelborg]

Did you create an impostor for the camera?
 

And if you did, you could just create an invisible mesh and make it the camera's parent.

[joshcamas]

Cool world btw!

[Floof]

Thanks Joshcamas for your advice and your support. The jump works now using space bar 

But I can't stop sliding on the mountains, because it's not a flat "ground", I suppose..

Do you think I can fix that ? 

 

http://www.peru-lab.com/quetzal/bishop2

[joshcamas]

I had the same problem, and it's kinda a hard one.

 

One thing you can try is saving a variable of the location of player, then applying gravity. Then compare the distances, and if the player should be standing, (aka not pressing buttons) and the distance is small, make the location the old one.

 

The only problem with this way is often you slide when you start pressing arrow keys again...

[Dinkelborg]

 

Thanks Joshcamas for your advice and your support.

So it seems joshcamas gave you a solution, why would you not share it here?

[joshcamas]

I think he might have been confused and read your post Dinkel, and thought it was me. :S

[Dinkelborg]

lol ... I got confused by his confusion then

[Floof]

Sorry for the delay guys...

Thank you very much for your answer. Maybe sliding is not a big problem finally... The most important thing is the jump,

and it works