java - 如何使粒子对象跟随鼠标移动

Question

我希望粒子对象在移动时简单地跟随 mouseX 和 mouseY 位置。我可以用 mouseX 和 Y 替换“origin”值吗？

  void run() {
    update();
    display();
  }

  // Method to update position
  void update() {
    velocity.add(acceleration);
    location.add(velocity);
    lifespan -= 2.0;
  }

    // Method to display
  void display() {
    stroke(0, lifespan);
    strokeWeight(2);
    fill(127, lifespan);
    ellipse(location.x, location.y, 12, 12);
  }

  // Is the particle still useful?
  boolean isDead() {
    if (lifespan < 0.0) {
      return true;
    } else {
      return false;
    }
  }
 }

Answer 1

这个例子更简单，更容易理解 - 希望它有所帮助。

float x;
float y;
float easing = 0.05;

void setup() {
  size(640, 360); 
  noStroke();  
}

void draw() { 
  background(51);

  float targetX = mouseX;
  float dx = targetX - x;
  x += dx * easing;

  float targetY = mouseY;
  float dy = targetY - y;
  y += dy * easing;

  ellipse(x, y, 66, 66);
}