使用按键（）方法的图像更改问题

Question

我正在尝试制作涂鸦跳跃游戏，目前我无法找到一种方法，一旦它落在地面上，就将静止图像更改为腿部图像，然后又变回静止图像。它为一方这样做，但不是为双方。我尝试过使用嵌套if，但随后它不会检测到按钮按下。代码如下：GameObject game;PImage doodle;void setup() {  size(640, 800);  smooth(4);  frameRate(10);  doodle = loadImage("https://i.imgur.com/ytwebph.png");  game = new Doodle(new PVector(width/2, height-doodle.height*2), doodle);  game.setWidthAndHeight(new PVector(width, height));}void draw() {  background(200);  game.display();  game.move();}void keyPressed() {  game.setMove(keyCode, true);}void keyReleased() {  game.setMove(keyCode, false);}protected class Doodle extends GameObject {  protected float velocityY, gravity, time;  protected float groundPosition;  protected int facing = 0; //0 = right; 1 = left  protected Doodle(PVector position, PImage picture) {    super(position, picture);    gravity = 20;    time = 0.4;    velocityY = 35*gravity*time;    super.setSpeed(10);    groundPosition = position.y - picture.height;  }  public void move() {    if (isRight || position.y < groundPosition) {      this.picture = doodleImg[0];      facing = 0;    } else if (isLeft || position.y < groundPosition) {      this.picture = doodleImg[2];      facing = 1;    }    position.x = position.x + speed*(int(isRight) - int(isLeft));    //border control    if (position.x+picture.width/2 <= 0) {      position.x = this.getWidthAndHeight().x-picture.width/2;    } else if (position.x+picture.width/2 >= this.getWidthAndHeight().x) {      position.x = 0-picture.width/2;    }    //jump    velocityY -=  gravity * time;    position.y -=  velocityY * time;    if (position.y >  groundPosition) {      if (facing == 0) {        this.picture = doodleImg[1];      } else if (facing == 1) {        this.picture = doodleImg[3];      }      position.y =  groundPosition;      velocityY = 35;    }  }}

Answer 1

首先设置状态，取决于 和：facingisRightisLeft

if (isRight) {

    facing = 0;

} else if (isLeft) {

    facing = 1;

}

设置图像取决于的状态和垂直位置：facingposition.y

if (position.y < groundPosition) {

    this.picture = doodleImg[facing==0 ? 0 : 2];

} else {

    this.picture = doodleImg[facing==0 ? 1 : 3];

}

https://i.stack.imgur.com/btjae.gif

public void move() {

    if (isRight) {

        facing = 0;

    } else if (isLeft) {

        facing = 1;

    }

    if (position.y < groundPosition) {

        this.picture = doodleImg[facing==0 ? 0 : 2];

    } else {

        this.picture = doodleImg[facing==0 ? 1 : 3];

    }

    position.x = position.x + speed*(int(isRight) - int(isLeft));

    //border control

    if (position.x+picture.width/2 <= 0) {

        position.x = this.getWidthAndHeight().x-picture.width/2;

    } else if (position.x+picture.width/2 >= this.getWidthAndHeight().x) {

        position.x = 0-picture.width/2;

    }

    //jump

    velocityY -=  gravity * time;

    position.y -=  velocityY * time;

    if (position.y >  groundPosition) {

        position.y =  groundPosition;

        velocityY = 35;

    }

}