Using pitch and yaw with movement?

[TechNick6425]

So, I'm trying to develop a game engine, and I have code that triggers when a key is pressed. I want the movement keys to move players in a certain direction based on their yaw. How would I do the math for this?

[quew8]

Forward Direction:
        dx = sin(yaw)
        dz = cos(yaw)

[TechNick6425]

Thanks! I wouldn't have figured that out myself! But, what would they be for sidesteping and backwards?

[Cornix]

To the side: +/- 90°
Backwards: +/- 180°

Assuming you have the angle (in degree) between your current position and the forward position you can just calculate the angle with the above arithmetics.

[TechNick6425]

Thanks!

[TechNick6425]

Well, I'm now working on an FPS, and I want to be able to throw grenades, but I need to find a solution for the Y velocity based on the pitch. How would I modify these to work?

[quew8]

With pitch as well, it's slightly more complicated.

    dx = cos(pitch) * sin(yaw)
    dy = sin(pitch)
    dz = cos(pitch) * cos(yaw)

[Turbots]

This is what I have at the moment:

switch (direction) {
	case BACKWARDS_OR_FORWARDS:
		position.z += amount * Math.sin(Math.toRadians(ry + 90));
		position.x += amount * Math.cos(Math.toRadians(ry + 90));
		position.y += amount * Math.sin(Math.toRadians(rx));
		break;
	case SIDEWAYS:
		position.z += amount * Math.sin(Math.toRadians(ry));
		position.x += amount * Math.cos(Math.toRadians(ry));
		break;
	case UP_OR_DOWN:
		// TODO: implement
	default:
		break;
}

[quew8]

Is that another question or a reply? Because the topic has already been answered (presumable since TechNick6425 hasn't replied in over a fortnight)

[TechNick6425]

Sorry for taking so long, but how would you reverse this formula? Say, pointing towards the coordinates of the mouse pointer.

[quew8]

You can take this formua

dy = sin(pitch)

and rearrange it to

pitch = arcsin(dy)

Then when you know pitch you can rearrange the other formulas to:

yaw = arcsin(dx / cos(pitch))

Giving you pitch and yaw. Hope this helps.