Example Mask

import h2d.RenderContext;
import h2d.Object;

class Mask extends hxd.App {

  var obj : h2d.Object;
  var mask : h2d.Mask;
  var time : Float = 0.;

  var apiMask : MaskWithSample;

  override function init() {
    mask = new h2d.Mask(160, 160, s2d);
    mask.x = 20;
    mask.y = 50;

    // Mask-sized rectangle to display mask boundaries
    // and make scroll movement more apparent.
    new h2d.Bitmap(h2d.Tile.fromColor(0x222222, mask.width, mask.height), mask);
    // Limit scroll
    mask.scrollBounds = h2d.col.Bounds.fromValues(-mask.width/2, -mask.height/2,mask.width*2, mask.height*2);

    obj = new h2d.Object(mask);
    obj.x = obj.y = 80;
    for( i in 0...10 ) {
      var b = new h2d.Bitmap(hxd.Res.hxlogo.toTile(), obj);
      b.scale(0.4);
      b.x = Std.random(200) - 100;
      b.y = Std.random(200) - 100;
    }
    var info = new h2d.Text(hxd.res.DefaultFont.get(), s2d);
    info.setPosition(5, 5);
    info.text = "Arrows: move scrollX/Y\nSpace: reset scroll to 0,0";

    // Content masking also possible with advanced `Mask.maskWith` and `Mask.unmask` methods.
    apiMask = new MaskWithSample(s2d);
    apiMask.setPosition(200, 50);
  }

  override function update(dt:Float) {
    time += dt;
    obj.rotation += 0.6 * dt;
    apiMask.sx = Math.cos(time) * 100 + 100;
    apiMask.sy = Math.sin(time) * 100 + 100;

    if (hxd.Key.isDown(hxd.Key.LEFT)) mask.scrollX -= 100 * dt;
    if (hxd.Key.isDown(hxd.Key.RIGHT)) mask.scrollX += 100 * dt;
    if (hxd.Key.isDown(hxd.Key.UP)) mask.scrollY -= 100 * dt;
    if (hxd.Key.isDown(hxd.Key.DOWN)) mask.scrollY += 100 * dt;
    if (hxd.Key.isReleased(hxd.Key.SPACE)) mask.scrollTo(0, 0);
  }

  static function main() {
    hxd.Res.initEmbed();
    new Mask();
  }

}

class MaskWithSample extends Object {

  public var sx:Float = 0;
  public var sy:Float = 0;

  public function new(?parent:Object) {
    super(parent);
    new h2d.Bitmap(hxd.Res.hxlogo.toTile(), this);
  }

  override function drawRec(ctx:RenderContext)
  {
    // Masking with advanced API allows to mask contents with objects that cannot use Mask as intermediary or extend from it.
    // For practical usage sample see h2d.Flow Hidden overflow mode.
    h2d.Mask.maskWith(ctx, this, 50, 50, sx, sy);
    super.drawRec(ctx);
    // Unmask should be called after `maskWith` in order to restore previous renderZone state.
    h2d.Mask.unmask(ctx);
  }

}

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