Question

我有一个旋转360度的枪精灵，我不想向任何方向射击子弹，我该怎么做？我不能只增加子弹的x，y坐标，因为它会上下左右移动。

编辑：子弹运动似乎只是旋转但不会去任何地方或屏幕外

 bulletPosition.x=MathUtils.cosDeg(cannonObj.cannonAngle())*2;
        bulletPosition.y=MathUtils.sinDeg(cannonObj.cannonAngle())*2;
        bulletVelocity.x=MathUtils.cosDeg(cannonObj.cannonAngle())*10;
        bulletVelocity.y=MathUtils.sinDeg(cannonObj.cannonAngle())*10;

        bulletPosition.x+=bulletVelocity.x*deltaTime;
        bulletPosition.y+=bulletVelocity.y*deltaTime;

//spawning bullets
 public void draw(SpriteBatch batch){
        bulletIterator=bullets.iterator();
        while(bulletIterator.hasNext()){
            Sprite sprite=bulletIterator.next();
            sprite.draw(batch);
            sprite.setPosition(bulletPosition.x,bulletPosition.y);
        }

Answer 1

Vector gunPos; // the gun position,dah
Vector bulletPos; //the bullet position
Vector bulletVelocity; //need explanation?
float gunAngle; //the rotation of the gun in degrees
float distanceFromCenter=gunSize.x/2; //the distance from the gun center you want the bullet to appear

bulletPos.x=MathUtils.cosDeg((gunAngle)) * distanceFromCenter;
bulletPos.y=MathUtils.cosDeg((gunAngle)) * distanceFromCenter;
bulletPos.plus(gunPos);

bulletVelocity.x=MathUtils.cosDeg((gunAngle)) * bulletSpeed;
bulletVelocity.y=MathUtils.cosDeg((gunAngle)) * bulletSpeed;

如何使物体向任何方向移动？

1 个答案: