'Thrust' Physics

Hey everyone. I've been looking everywhere for tutorials and they seem rare, even for code, never mind construct!

I'm looking to prototype a simple space shooter type movement, something like Asteroids, Thrust etc. I've gotten a basic setup done with custom movement, and I think I understand how that particular object works... but I'm trying to implement the correct physics, using events and avoiding using many of the built in behaviours. This is only because I prefer to know what's going on and don't like the idea of something changing in another version and breaking everything

So I suppose what I'm stuck on is how to implement the movement of a single sprite... I want to use vectors maths but I'm unsure what the correct way to implement them would be. I assume you should set up separate private variables like XPostion, YPosition, Angle... is there any advantage to making a few vector functions (dot product, cross product etc) or can Construct do all this anyway? (I've not been through every single event yet so I might be mistaken)...

Also I'm a bit confused about the way angles are implemented, with 0 being right rather than up like I was used to. Will this cause problems when calculating rotations and inertia and all that? Furthermore it all has to work with delta time, have acceleration/deceleration for rotation as well as the same for movement itself.

Any ideas would be helpful, it's been a while since I've looked at any maths in detail

Cheers

Absolute genius, thanks mr. hound

I love it, it's got a great feel to it, I've just added some additional private variables 'ThrustSpeed' and 'RotationSpeed' and adjusted the events so that the numbers 100 and 200 should be easier to play around with. Any idea how I could get the rotation to decelerate when the left/right arrow isn't being pressed? It'd be good to be able to prevent the ship spinning out of control so easily So that the ship keeps moving in the right direction due to it's inertia, but the player can point it in the direction they want it to move more easily... I suppose that's more 'arcade' control than real physics but I'd like to play with the options

Actually the 200 and 100 are linear and angular acceleration, not speeds.

For angular deceleration:
[code:3q26kvpc]+ MouseKeyboard: [negated] Key Left arrow is down
+ MouseKeyboard: [negated] Key Right arrow is down
-> Sprite: Subtract 2*'AngularVelocity'*TimeDelta from 'AngularVelocity'
[/code:3q26kvpc]
2 is the deceleration amount .

On a side note the physics behavior is way better suited for this type of movement, as it takes very little to set up.

I managed to piece something together using some things I learned browsing the forum, seems the physics behaviour route might be more ideal anyways since the collisions are already handled much better that I could probably implement them

[url:3d7p3lo6]http://www.mediafire.com/file/o1zvm0muyjb/Ast_Physics_1.cap[/url:3d7p3lo6]

Any ways to improve this? The torque/rotation doesn't use DeltaTime, I'm not sure about that :S

I don't know, something feels a tad bit jagged and unnatural about the thrust, what do people think?

Ah I wasn't aware of that, that's made things a lot easier

It looks much more readable now, cheers again for the help It's taking me a while to get my head round the physics behaviour because a lot of the values (angle damping etc) dont seem to have any effect :S I've been trying to adjust the rate of deceleration/acceleration so the turning is more responsive, yet can't seem to figure if this is possible with the torque values. There are so many implementations on the box2d forum haha