Angle between two points and calculating the rotation

问题

so I'm currently programming a little game in Java with libGDX.

I want the players texture to directly rotate to the mouse position. Unfortunately my code doesn't work, and I have absolutely no idea why not.

So, I call this method in the Update method of the player:

private void CalculateRotation()
{
    rotation = Position.angle(input.getTranslatedMousePos());
}

The Position is just a Vector2 with the players position. I get the translatedMousePos like this:

public Vector2 getTranslatedMousePos()
{
    Vector3 v = camera.unproject(new Vector3(MousePos.x, MousePos.y, 0));

    return new Vector2(v.x, v.y);
}

while MousePos is determined by the following code:

@Override
public boolean mouseMoved(int screenX, int screenY) {
    MousePos = new Vector2(screenX, screenY);
    return false;
}

I draw the players sprite like this:

public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.draw(new TextureRegion(txt), Position.x, Position.y, (float)(size.x * 0.5), (float)(size.y * 0.5), size.x, size.y, 1.0f, 1.0f, rotation);
}

Unfortunately the sprite turns, but in no way pointing to the cursor.

Following things I figured out yet:

spriteBatch.draw(...,rotation) accepts degrees and Vector2.angle gives the angle in degrees
the translatedMousePos seems to be right, I figured that out by hovering over the players sprite (which is at (1000|-1000)) and "printing" the translatedMousePos, it was the same

Thank you for taking your time and helping me! :)

来源：https://stackoverflow.com/questions/29412383/angle-between-two-points-and-calculating-the-rotation

标签

java

vector

rotation

libgdx