處理js跳轉系統

Question

我試圖在processing.js中創建一個跳轉系統，並且完成了它，但不是我想要的。事情就是這樣，跳高取決於按鍵的時間長短。無論按下多長時間，我所需要的是相同的高度。

這裏是我的代碼：

var keys = []; 
void keyPressed() { 
    keys[keyCode] = true; 
}; 
void keyReleased() { 
    keys[keyCode] = false; 
}; 

var Player = function(x, y) { 
    this.x = x; 
    this.y = y; 
    this.g = 0; 
    this.vel = 2; 
    this.jumpForce = 7; 
    this.jump = false; 
}; 
Player.prototype.draw = function() { 
    fill(255,0,0); 
    noStroke(); 
    rect(this.x, this.y, 20, 20); 
}; 
Player.prototype.move = function() { 
    if(this.y < ground.y) { 
     this.y += this.g; 
     this.g += 0.5; 
     this.jump = false; 
    } 
    if(keys[RIGHT]) { 
     this.x += this.vel; 
    } 
    if(keys[LEFT]) { 
     this.x -= this.vel; 
    } 

    //preparing to jump 
    if(keys[UP] && !this.jump) { 
     this.jump = true; 
    } 
    // if jump is true, than the ball jumps... after, the gravity takes place pulling the ball down... 
    if(this.jump) { 
     this.y -= this.jumpForce; 
    } 
}; 
Player.prototype.checkHits = function() { 
    if(this.y+20 > ground.y) { 
     this.g = 0; 
     this.y = ground.y-20; 
     jump = false; 
    } 
}; 

Var Ground = function(x, y, label) { 
    this.x = x; 
    this.y = y;this.label = label; 
}; 
Ground.prototype.draw = function() { 
    fill(0); 
    rect(0, 580, width, 20); 
}; 

var player = new Player(width/2, height/2); 
var ground = new Ground(0, 580, "g"); 
void draw() { 
    background(255,255,255); 
    player.draw(); 
    player.move(); 
    player.checkHits(); 
    ground.draw(); 
} 

任何幫助將aprreciated。

Answer 1

你在這裏做什麼就像是：「如果這個（玩家）沒有接觸地面，那麼，如果（另外）按鍵UP被按下，則跳躍！」。所以它可以讓玩家跳躍，即使他在空中......增加跳躍高度

你應該這樣做：「如果玩家觸摸地面允許跳躍（如果向上按鍵），否則你已經在跳躍！「。

事情是這樣的：

if(this.y < ground.y) { 
    this.y += this.g; 
    this.g += 0.5; 
    this.jump = true; 
} 
else{ 
    this.jump = false; 
} 

if(keys[UP] && !this.jump) { 
    this.jump = true; 
    this.y -= this.jumpForce; 
}