碰撞檢測，然後讓玩家停止

Question

我正在使用處理，我想創建一個遊戲，玩家在一個房間裏，如果他們撞牆，他們會像普通牆壁一樣停下來。不過，我真的不知道如何做到這一點。使用我目前的方法，一旦他們撞上了牆，他們就無法再在X軸上移動了。任何幫助將不勝感激。

PVector playerPosition; 
PVector barrierPosition; 

float velocity = 4; 

boolean goLeft=false; 
boolean goRight=false; 
boolean goUp=false; 
boolean goDown=false; 

float playerWidth = 10; 
float playerHeight = 10; 

float barrierWidth = 10; 
float barrierHeight = 600; 



void setup() { 
    size(800,600); 
    rectMode(CORNER); 
    playerPosition = new PVector(200,200); 
    barrierPosition = new PVector(0,0); 
} 

void draw() { 
background(255); 
drawPlayer(); 
movePlayerPosition(); 
drawBarrier(); 
checkCollide(); 



} 
    //check for collision with barrier then stop player moving 
    void checkCollide() { 
    if (playerPosition.y <= barrierHeight + playerHeight && playerPosition.x <= barrierWidth + playerWidth) 
    { 
    println("COLLIDED"); 
    playerPosition.x = barrierPosition.x + 10; 
    } 

    } 

void drawPlayer() { 
    fill(255,0,0); 
    rect(playerPosition.x,playerPosition.y,playerWidth,playerHeight); 
} 
void drawBarrier() { 
    fill(0); 
    rect(barrierPosition.x,barrierPosition.y,barrierWidth,barrierHeight); 
} 

void movePlayerPosition() { 

    //moves up and down 
    if (goUp && playerPosition.y > 0) 
    { 
     playerPosition.y = playerPosition.y - velocity; 
    } else if (goDown && playerPosition.y < 598-playerHeight) 
    { 
     playerPosition.y = playerPosition.y + velocity; 
    } 

    //moves right and left 
    if (goLeft && playerPosition.x > 0) 
    { 
     playerPosition.x = playerPosition.x -velocity; 
    } else if (goRight && playerPosition.x <800-playerWidth) 
    { 
     playerPosition.x = playerPosition.x + velocity; 
    } 
    } 

    //if the keys are pressed move in that direction 
void keyPressed() { 
    if (key == 'w') { 
    goUp=true; 
    } else if (key == 'a') { 
    goLeft=true; 
    } else if (key == 's') { 
    goDown=true; 
    } else if (key == 'd') { 
    goRight=true; 
    } 
} 
//if the keys are released stop moving 
void keyReleased() { 
    if (key == 'w') { 
    goUp=false; 
    } else if (key == 'a') { 
    goLeft=false; 
    } else if (key == 's') { 
    goDown=false; 
    } else if (key == 'd') { 
    goRight=false; 
    } 
} 

Answer 1

第一個簡單的答案;你的checkForCollide方法應該返回一個布爾值而不是void，那麼你可以使用這個方法和movePlayerPosition，並且只有在沒有碰撞時才執行X軸移動。

現在，在一個更完整的答案;您應該多關注一下這個主題，有很多模式和庫可以更好，更輕鬆地處理這個主題。 我推薦你Nature of code，你可以免費得到這個pdf，你有很多關於使用第5章中的物理圖書館，還有很多關於編程遊戲的樣本。

希望這會有所幫助，祝你好運。 Regards Jose

Answer 2

你太親近了！

這一行後：

println("COLLIDED"); 

設置像這樣的新座標：

playerPosition.x = barrierPosition.x + 10; 

這意味着第一次衝突發生的地方之後，X位置總是被設置爲barrierPosition.x + 10;

你可能想要做的是將播放器移動10個像素，但相對於它的當前位置：

playerPosition.x = playerPosition.x + 10; 

或：

playerPosition.x += 10; 

玩得開心！

僅供參考，您有幾個字符完整的代碼修改：

PVector playerPosition; 
PVector barrierPosition; 

float velocity = 4; 

boolean goLeft=false; 
boolean goRight=false; 
boolean goUp=false; 
boolean goDown=false; 

float playerWidth = 10; 
float playerHeight = 10; 

float barrierWidth = 10; 
float barrierHeight = 600; 



void setup() { 
    size(800,600); 
    rectMode(CORNER); 
    playerPosition = new PVector(200,200); 
    barrierPosition = new PVector(0,0); 
} 

void draw() { 
background(255); 
drawPlayer(); 
movePlayerPosition(); 
drawBarrier(); 
checkCollide(); 



} 
    //check for collision with barrier then stop player moving 
    void checkCollide() { 
    if (playerPosition.y <= barrierHeight + playerHeight && playerPosition.x <= barrierWidth + playerWidth) 
    { 
    println("COLLIDED"); 
    playerPosition.x += 10; 
    } 

    } 

void drawPlayer() { 
    fill(255,0,0); 
    rect(playerPosition.x,playerPosition.y,playerWidth,playerHeight); 
} 
void drawBarrier() { 
    fill(0); 
    rect(barrierPosition.x,barrierPosition.y,barrierWidth,barrierHeight); 
} 

void movePlayerPosition() { 

    //moves up and down 
    if (goUp && playerPosition.y > 0) 
    { 
     playerPosition.y = playerPosition.y - velocity; 
    } else if (goDown && playerPosition.y < 598-playerHeight) 
    { 
     playerPosition.y = playerPosition.y + velocity; 
    } 

    //moves right and left 
    if (goLeft && playerPosition.x > 0) 
    { 
     playerPosition.x = playerPosition.x -velocity; 
    } else if (goRight && playerPosition.x <800-playerWidth) 
    { 
     playerPosition.x = playerPosition.x + velocity; 
    } 
    } 

    //if the keys are pressed move in that direction 
void keyPressed() { 
    if (key == 'w') { 
    goUp=true; 
    } else if (key == 'a') { 
    goLeft=true; 
    } else if (key == 's') { 
    goDown=true; 
    } else if (key == 'd') { 
    goRight=true; 
    } 
} 
//if the keys are released stop moving 
void keyReleased() { 
    if (key == 'w') { 
    goUp=false; 
    } else if (key == 'a') { 
    goLeft=false; 
    } else if (key == 's') { 
    goDown=false; 
    } else if (key == 'd') { 
    goRight=false; 
    } 
}