Please help me!

Question about the task

Moon Lander (Part 12/23)

Games, Level 0, Lesson 4

Under discussion

Please help me! I don't know the right answer for the last 3 task :(

As you’ve noticed, after the left or right key is released, the rocket stops moving immediately, but it should continue moving from inertia. To achieve this, we will use the slowdown variable, which is responsible for slowing the rocket. If we release the left or right key, the move method will gradually reduce the rocket’s speedX variable by the value of slowdown, until it reaches 0.

Requirements:

The Rocket class must have a double private slowdown field that is initialized to boost/10 when it is declared.
In the move(boolean, boolean, boolean) method, the speedX field must be set to 0 if the method's isLeftPressed parameter is false, the method's isRightPressed parameter is false, and the value of the speedX field is between (-slowdown) and (+slowdown) inclusive.
In the move(boolean, boolean, boolean) method, the speedX field must decrease by the value of slowdown if the method's isLeftPressed parameter is false, the method's isRightPressed parameter is false, and the value of the speedX field is greater than the value of slowdown.
In the move(boolean, boolean, boolean) method, the speedX field must increase by the value of slowdown if the method's isLeftPressed parameter is false, the method's isRightPressed parameter is false, and the value of the speedX field is less than the value of (-slowdown).
In the move(boolean, boolean, boolean) method, the x field must be increased by the value of speedX after the speedX field has been changed and before the call to the checkBorders() method.

package com.codegym.games.moonlander; public class Rocket extends GameObject { private double speedY = 0; private double boost = 0.05; private double speedX = 0; private double slowdown = boost/10; public Rocket(double x, double y) { super(x, y, ShapeMatrix.ROCKET); } public void move(boolean isUpPressed, boolean isLeftPressed, boolean isRightPressed){ if(!isRightPressed && !isLeftPressed){ if(speedX > -1*slowdown && speedX < slowdown)speedX = 0; else if(speedX > slowdown)speedX -= slowdown; else if(speedX < -1*slowdown)speedX += slowdown; } if(isUpPressed){ speedY -= boost; }else if(isLeftPressed){ speedX -= boost; x += speedX; }if(isRightPressed) { speedX += boost; x += speedX; }else { speedY += boost; } y += speedY; checkBorders(); } private void checkBorders(){ if( x < 0) { x = 0; speedX = 0; } double sum = x + width; if(sum > width) { x = MoonLanderGame.WIDTH - width; speedX = 0; } if(y < 0){ y = 0; speedY = 0; } } }

Comments (2)

Popular
New
Old

You must be signed in to leave a comment

Guadalupe Gagnon

Level 37 , Tampa, United States

16 October 2019, 17:41

You need to try and keep your code simple. Too many Boolean checks creates unnecessary complicated code:

public void move(boolean isUpPressed, boolean isLeftPressed, boolean isRightPressed) {
        if (isUpPressed)
            speedY -= boost;
        else
            speedY += boost;

        if (isLeftPressed)
            speedX -= boost;
        else if (isRightPressed)
            speedX += boost;
            // ↓ neither right or left is pressed
        else if (speedX > slowdown)
            speedX -= slowdown;
        else if (speedX < -slowdown)
            speedX += slowdown;
            // ↓ speed is less than -slowdown or greater than slowdown
        else
            speedX = 0;

        y += speedY;
        x += speedX;
        checkBorders();
}

Letenyei Ádám

Level 16 , Bakonyszombathely, Magyarország

16 October 2019, 18:01

Thank you! I tried your solution, but the last 3 task not verify....