minimap

scissorTest is important!

by otorineko6790

HTML

<div id="info">Mini Map
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/84/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js">


</script>
<script src="https://jyunming-chen.github.io/tutsplus/js/KeyboardState.js"></script>

CSS

#info {
  position: absolute;
  top: 0px;
  width: 100%;
  padding: 10px;
  text-align: center;
  color: #ffff00
}

body {
  overflow: hidden;
}

JavaScript

var camera, scene, renderer;
var cameraHUD1, cameraHUD2, sceneHUD;
var keyboard = new KeyboardState();

init();
animate();

function initHUD() {
  // sceneHUD: a simple line boundary

  cameraHUD2 = new THREE.OrthographicCamera(-15,15,15,-15,-35,35);
  cameraHUD2.position.set (0,30,0)
  cameraHUD2.up.set (0,0,-1)   // for top view
  cameraHUD2.lookAt (new THREE.Vector3())
  
}

function init() {

  renderer = new THREE.WebGLRenderer();
  renderer.setSize(window.innerWidth, window.innerHeight);
  renderer.setClearColor(0x888800);
  document.body.appendChild(renderer.domElement);
  
  scene = new THREE.Scene();

  camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
  camera.position.z = 25;

	let controls = new THREE.OrbitControls(camera, renderer.domElement);

	/////////////////////////////////////////////
  var geometry = new THREE.BoxGeometry(10, 2, 2);
  var material = new THREE.MeshLambertMaterial();

  var mesh = new THREE.Mesh(geometry, material);
  scene.add(mesh);

  var light = new THREE.PointLight(0xffffff);
  light.position.set(100, 300, 200);
  scene.add(light);

  var gridXZ = new THREE.GridHelper(20, 10, 'red', 'white');
  scene.add(gridXZ);

	initHUD();
  renderer.autoClear = false;

}

function animate() {

  requestAnimationFrame(animate);
  render();

}

function render() {

  var WW = window.innerWidth;
  var HH = window.innerHeight;

  renderer.setScissorTest(true);

  renderer.setViewport(0, 0, WW, HH);
  camera.aspect = WW / HH;
  camera.updateProjectionMatrix();
  
  renderer.setScissor(0, 0, WW, HH);
  renderer.clear();
  renderer.render(scene, camera);

  renderer.setViewport(WW / 2, HH / 2, WW / 3, HH / 3);
  renderer.setScissor(WW / 2, HH / 2, WW / 3, HH / 3);
  // no need to set aspect (since it is still ONE)
  renderer.clear();  // important!

  renderer.render(scene, cameraHUD2);     // topview

	renderer.setScissorTest(false);
}