Drift for 2D Space Game

[Slyth2727]

GUYS IM NOT DEAD. My computer just crashed and I managed to install ubuntu on it to start programming again. I went 2 months without programming D:! Anyways, remember those old top down racing games where you just guided that car along the track and get as much "drift" as possible? How would I implement that in my libgdx game? Just in case you need it, here's the spaceship class:

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package com.slyth.spaceGame.Models; import com.badlogic.gdx.Gdx; import com.badlogic.gdx.math.MathUtils; import com.badlogic.gdx.math.Rectangle; import com.badlogic.gdx.math.Vector2; public class Ship extends MovableEntity {    public boolean left = false, right = false, up = false, down = false, isKeyDown = false;    float rotateSpeed = 30, health = 100, SPEEDORIG;    Rectangle pickupBounds;    boolean isUpgradedSpeed = false;    public int usT = 0, usP = 400;    public Ship(Vector2 position, float width, float height, float rotation, float SPEED) {       super(SPEED, rotation, width, height, position);       this.SPEEDORIG = SPEED;       pickupBounds = new Rectangle(position.x - ((width * 3) / 2), position.y - ((height * 3) / 2), width * 3, height * 3);    }    public void update() {       if (isUpgradedSpeed) {          if (usT >= usP) {             isUpgradedSpeed = false;             SPEED = SPEEDORIG;             usP = 400;             usT = 0;          } else {             SPEED = SPEEDORIG + 2;             usT++;          }       }       pickupBounds = new Rectangle(position.x - ((width * 10) / 2.5f), position.y - ((height * 10) / 2.5f), width * 10, height * 10);       if (left) {          if (rotation <= 360) {             rotation += .1f * rotateSpeed - 0.03;          } else {             rotation = 0;             rotation += .1f * rotateSpeed - 0.03;          }       } else if (right) {          if (rotation >= 0) {             rotation += -.1f * rotateSpeed - 0.03;          } else {             rotation = 360;             rotation += -.1f * rotateSpeed - 0.03;          }       }       if (up) {          float yP = MathUtils.sinDeg(rotation + 90) * SPEED;          float xP = MathUtils.cosDeg(rotation + 90) * SPEED;          velocity.y = yP;          velocity.x = xP;       } else if (!up && !down) {          velocity.x *= .95;          velocity.y *= .95;       } else if (down) {          float yP = MathUtils.sinDeg(rotation + 90) * SPEED;          float xP = MathUtils.cosDeg(rotation + 90) * SPEED;          velocity.y = -yP;          velocity.x = -xP;       }       if(!isKeyDown){       }       position.add(velocity.tmp().mul(Gdx.graphics.getDeltaTime() * SPEED));       bounds.x = position.x;       bounds.y = position.y;    }    public float getHealth() {       return health;    }    public Rectangle getPickupBounds() {       return pickupBounds;    }    public void setHealth(float am) {       health = am;    }    public void loseHealth(float am) {       health -= am;    }    public void heal(float am) {       health += am;    }    public void upgradeSpeed() {       if (!isUpgradedSpeed) {          isUpgradedSpeed = true;       } else {          usP += 400;       }    }    public boolean isSpeedUpgraded() {       return isUpgradedSpeed;    } }

Thanks
-cMp

[HeroesGraveDev]

Drifting is caused when you change the direction you're facing, without changing the direction of your motion (at least temporarily).

Think about that for a bit.

[Slyth2727]

so I should do some sort of time step after I rotate to move in the same direction for a small bit? From what I am thinking that actually would make it like a racing game. I didn't make it clear, I need the effect of 0 gravity so that it would drag like a racing game, but still move in the direction you are facing.

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[HeroesGraveDev]

so I should do some sort of time step after I rotate to move in the same direction for a small bit? From what I am thinking that actually would make it like a racing game. I didn't make it clear, I need the effect of 0 gravity so that it would drag like a racing game, but still move in the direction you are facing.

That would be fine. I recommend doing that.

But for a more realistic effect it would be a good idea to learn basic kinematics.

[Slyth2727]

Will do, thanks. Also, if you know of an easier/better way to do time steps in libGDX instead of the standard

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if(firstVar >= secVar){ var++: firstVar=0; }else{ firstVar++: }

could you tell me?

[HeroesGraveDev]

What do you mean by time step?

[Slyth2727]

the process where you increase or decrease a variable over time in the code. An example is up there in the ship class where if the ship is not being moved I do velocity.x *= .98f to make the ship slow down over time. However the type I meant was where you have a first variable (varOne), and a second (varTwo), and compare them to eachother to edit a variable over time. Hard to explain I guess

[HeroesGraveDev]

So every X ticks, you increment a variable by one?

In that case:

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firstVar--; if(firstVar == 0) {     firstVar = secVar;     var++; }

Kind of does the same thing. Not sure if it's more optimised. It's just easier to code.

[Slyth2727]

Ah ok, thanks. I have been searching the kinematics you suggested and I haven't found anything related to drifting. Is there some simple math that you can write down in just a couple seconds if it doesn't bother you? Thanks

[HeroesGraveDev]

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// Vector2 facingVector // Vector2 movingVector // float inertia // float acceleration movingVector -= multiply(normalize(movingVector), inertia); movingVector += multiply(normalize(facingVector), acceleration);

Requires some knowledge of vector math.
Can probably be optimised.

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[Slyth2727]

Gotcha, thanks!