XNA Diagonal Movement Key Release

Question

Ok, so say you're playing a top down game. You press W and D to go in the up-right direction. Now you just want to go right, so you release the W key. One would expect you to then change directions and head right, but instead, you continue up-right. What can I do to solve this problem? Here is my code:

        if (kb.IsKeyDown(Keys.W) || kb.IsKeyDown(Keys.A) || kb.IsKeyDown(Keys.S) || kb.IsKeyDown(Keys.D))
        {
            if (kb.IsKeyDown(Keys.W))
                velocity.Y = -movespeed;
            else if (kb.IsKeyDown(Keys.A))
                velocity.X = -movespeed;
            else if (kb.IsKeyDown(Keys.S))
                velocity.Y = movespeed;
            else if (kb.IsKeyDown(Keys.D))
                velocity.X = movespeed;
            else if (kb.IsKeyDown(Keys.W) && kb.IsKeyDown(Keys.D))
            {
                velocity.X = movespeed;
                velocity.Y = -movespeed;
            }
            else if (kb.IsKeyDown(Keys.W) && kb.IsKeyDown(Keys.A))
            {
                velocity.X = -movespeed;
                velocity.Y = -movespeed;
            }
            else if (kb.IsKeyDown(Keys.S) && kb.IsKeyDown(Keys.D))
            {
                velocity.X = movespeed;
                velocity.Y = movespeed;
            }
            else if (kb.IsKeyDown(Keys.S) && kb.IsKeyDown(Keys.A))
            {
                velocity.X = -movespeed;
                velocity.Y = movespeed;
            }
        }
        else
            velocity *= .9f;

        position += velocity;

omni · Accepted Answer · 2015-05-04T21:59:18.703

1

So I figured out the answer myself after a few hours of struggle.

Simply setting the velocity to zero before the checks worked: EDIT: multiplying it by .89 actually made for much smoother movement.

        if (kb.IsKeyDown(Keys.W) || kb.IsKeyDown(Keys.A) || kb.IsKeyDown(Keys.S) || kb.IsKeyDown(Keys.D))
        {
            velocity *= .89f
            if (kb.IsKeyDown(Keys.W))
                velocity.Y = -movespeed;
            if (kb.IsKeyDown(Keys.A))
                velocity.X = -movespeed;
            if (kb.IsKeyDown(Keys.S))
                velocity.Y = movespeed;
            if (kb.IsKeyDown(Keys.D))
                velocity.X = movespeed;
        }
        else
            velocity *= .9f;

edited May 04 '15 at 21:59

answered May 03 '15 at 22:23

omni

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did you consider that diagonal speed is faster than moving up/down/left/right? one solution is to normalize velocity and then multiply by speed. other is to divide speed by `sqrt(2)` if movement is diagonal. – Davor Mlinaric May 04 '15 at 10:42
No, I didn't. Could you elaborate? – omni May 04 '15 at 22:00
The diagonal speed will be `speed magnitude * sqrt(2)`. – snahor May 10 '15 at 02:35

XNA Diagonal Movement Key Release

1 Answers1