我想知道如何在游戏中顺利跳跃。它是一个2D游戏,代码非常简单,但我想知道如何让它在达到最大高度然后平滑下降时减慢速度。
这就是我跳跃的全部内容:
Player.y -= 50;
答案 0 :(得分:1)
你最好的选择是使用物理引擎(Box2d等)。如果你不想要一个开销(如果你唯一使用它的是跳跃而不是碰撞)那么你只需要为你的逻辑添加一些摩擦。
var friction :Number = .85; //how fast to slow down / speed up - the lower the number the quicker (must be less than 1, and more than 0 to work properly)
var velocity :Number = 50; //how much to move every increment, reset every jump to default value
var direction :int = -1; //reset this to -1 every time the jump starts
function jumpLoop(){ //lets assume this is running every frame while jumping
player.y += velocity * direction; //take the current velocity, and apply it in the current direction
if(direction < 0){
velocity *= friction; //reduce velocity as player ascends
}else{
velocity *= 1 + (1 - friction); //increase velocity now that player is falling
}
if(velocity < 1) direction = 1; //if player is moving less than 1 pixel now, change direction
if(player.y > stage.stageHeight - player.height){ //stage.stageheight being wherever your floor is
player.y = stage.stageHeight - player.height; //put player on the floor exactly
//jump is over, stop the jumpLoop
}
}
答案 1 :(得分:0)
复制/粘贴以下代码... jump()可以替换为jump2()(没有弹跳效果)。跳跃将由空格键产生:
const FA:Number = .99; // air resistance
const CR_BM:Number = .8; // bouncing coefficient
const µ:Number = .03; // floor friction
const LB:int = stage.stageHeight; // floor (bottom limit)
const G:int = 2.5; // gravity
const R:int = 50;
var ball:MovieClip = new MovieClip();
this.addChild(ball);
var ba:* = ball.graphics;
ba.beginFill(0xFFCC00);
ba.lineStyle(0, 0x666666);
ba.drawCircle(0, 0, R);
ba.endFill();
ball.vx = 2;
ball.vy = -30;
ball.r = R;
ball.x = 100;
ball.y = LB - R;
stage.addEventListener(KeyboardEvent.KEY_DOWN, myKeyDown);
function myKeyDown(e:KeyboardEvent):void {
if (e.keyCode == Keyboard.SPACE) {
ball.vy = -30;
addEventListener(Event.ENTER_FRAME, jump);
}
}
function jump(e:Event):void {
ball.vy = ball.vy + G;
ball.vx *= FA;
ball.vy *= FA;
ball.x += ball.vx;
ball.y += ball.vy;
if (ball.y > LB - ball.r) {
ball.y = LB - ball.r;
ball.vy = -1 * ball.vy * CR_BM;
ball.vx += ball.vx * - µ;
}
}
/*
function jump2(e:Event):void {
ball.vy = ball.vy + G;
ball.vx *= FA;
ball.vy *= FA;
ball.x += ball.vx;
ball.y += ball.vy;
if (ball.y > LB - ball.r) {
ball.y = LB - ball.r;
}
}
*/