processing - 将鼠标拖到可点击区域之外

Question

我正在尝试从头开始编写一个滑块，并且我有一个基本功能，但我希望能够将滑块拖动到我为单击它而创建的范围之外。

void slide()
{
  if ((x+w >= mouseX) && (mouseX >= x) && (y+h >= mouseY) && (mouseY >= y) &&
      (mousePressed == true))
  { 
      h = (mouseY - y);
  }

正如您所看到的，当鼠标被拖动到滑块尺寸之外时，高度值不再改变。如何仅在维度内激活然后拖动到维度之外？

Answer 1

我已经通过一个布尔值来控制点击和锁定，例如：

class Test {
  //global  
  float x;
  float y;
  float w, h;
  float initialY;
  boolean lock = false;

  //constructors

  //default
  Test () {
  }

  Test (float _x, float _y, float _w, float _h) {
    x=_x;
    y=_y;
    initialY = y;
    w=_w;
    h=_h;
  }


  void run() {

    float lowerY = height - h - initialY;
    float value = map(y, initialY, lowerY, 100, 255);
    color c = color(value);
    fill(c);
    rect(x, initialY, 4, lowerY);
    fill(200);
    rect(x, y, w, h);
    float my = constrain(mouseY, initialY, height - h - initialY );
    if (lock) y = my;
  }


  boolean isOver()
  {
    return (x+w >= mouseX) && (mouseX >= x) && (y+h >= mouseY) && (mouseY >= y);
  }
}


//end of class

Test[] instances =  new Test[3]; 

void setup() {
  size(200, 600);
  noStroke(); 
  instances[0] = new Test(20, 20, 40, 20);
  instances[1] = new Test(80, 20, 40, 20);
  instances[2] = new Test(140, 20, 40, 20);
}

void draw() {
  background(100);
  for (Test t:instances)
    t.run();
}


void mousePressed() {
  for (Test t:instances)
  {
    if (t.isOver())
      t.lock = true;
  }
}

void mouseReleased() {
  for (Test t:instances)
  {
      t.lock = false;
  }
}