我如何逐步进行此操作？

Question

我正在使用处理程序，目前正在尝试使矩形逐步移动（特别是8步移动），但是我遇到了麻烦。有人可以帮我吗？

//Declare variables
int x = 0;
int dx = 1;
boolean move = true;

void setup() {
  //Set screen size
  size (1280, 720);
}

void draw() {
  //Set Background to white
  background (240, 240, 240);
  fill(255, 147, 79); 
  noStroke();
  rectMode(CORNER);
  //Draw the rectangle
  rect(0, x, width/14.22, height/8); 

  //IF statement that will only run if the move variable is true
  if (move == true) {
    //Set the x variable to current x value plus the value of the dx variable
    x = x + dx;
    //IF statement that will only run if the x variable is larger then height - height/8
    if (x > height - height/8) {
      //Set dx to -1
      dx = -1;
    } 
    //IF statement that will only run if the x variable minus 10 is less then 0
    if (x < 0) {
      //Set dx to -1
      dx = 1;
    }
  }
}

void keyPressed() {
  //IF statement that will only run if keyCode variable is equal to 32 (SpaceBar)
  if (keyCode == 32) {
    //Flip the move variable
    move = !move;
  }
}

Answer 1

如果矩形应为正方形，并且应为窗口高度的八分之一，则高度为height/8，宽度与高度相同：

rect(0, y, height/8, height/8);

如果矩形应以8步上下移动，则使用步骤索引step_i。矩形的y坐标取决于索引：

int y = step_i*height/8;
rect(0, y, height/8, height/8); 

如果索引为<= 0或> = 7则更改方向：

step_i += dy;
if (step_i <= 0 || step_i >= 7) {
    dy *= -1;
}

示例代码：

int dy = 1;
int step_i = 0;

void draw() {
    //Set Background to white
    background (240, 240, 240);
    fill(255, 147, 79); 
    noStroke();
    rectMode(CORNER);

    //Draw the rectangle
    int y = step_i*height/8;
    rect(0, y, height/8, height/8); 

    //IF statement that will only run if the move variable is true
    if (move == true) {
        step_i += dy;
        if (step_i <= 0 || step_i >= 7) {
            dy *= -1;
        }
    }
}