"use strict"; // 參考 https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Strict_mode
////////////////////////////////////////////////////////////////////////////////
// 挑出一個字，數字 1
// 修改 SquareGeometry 裡的 UV 值
// 從貼圖中挑出數字 1
// 你只能修改 uvs 陣列
////////////////////////////////////////////////////////////////////////////////
var camera, scene, renderer;
var cameraControls, effectController;
var clock = new THREE.Clock();

function SquareGeometry() {
	var geo = new THREE.Geometry();

// 產生頂點
	geo.vertices.push( new THREE.Vector3( 0.0, 0.0, 0.0 ) );
	geo.vertices.push( new THREE.Vector3( 1.0, 0.0, 0.0 ) );
	geo.vertices.push( new THREE.Vector3( 1.0, 1.0, 0.0 ) );
	geo.vertices.push( new THREE.Vector3( 0.0, 1.0, 0.0 ) );

// 修改這個陣列選取貼圖的正確部位
	var uvs = [];
	uvs.push( new THREE.Vector2( 0.0, 0.0 ) );
	uvs.push( new THREE.Vector2( 1.0, 0.0 ) );
	uvs.push( new THREE.Vector2( 1.0, 1.0 ) );
	uvs.push( new THREE.Vector2( 0.0, 1.0 ) );

// 產生面
	geo.faces.push( new THREE.Face3( 0, 1, 2 ) );
	geo.faceVertexUvs[ 0 ].push( [ uvs[0], uvs[1], uvs[2] ] );
	geo.faces.push( new THREE.Face3( 0, 2, 3 ) );
	geo.faceVertexUvs[ 0 ].push( [ uvs[0], uvs[2], uvs[3] ] );

// 完成：回傳
	return geo;
}

function fillScene() {
	scene = new THREE.Scene();

var myPolygon = new SquareGeometry();
	var myTexture = THREE.ImageUtils.loadTexture( '/cs291/texture/lettergrid.png' );
	var myPolygonMaterial = new THREE.MeshBasicMaterial( { map: myTexture } );
	var polygonObject = new THREE.Mesh( myPolygon, myPolygonMaterial );
	scene.add(polygonObject);
}

function init() {
	canvasWidth = window.innerWidth;
	canvasHeight = window.innerHeight;
	var canvasRatio = canvasWidth/canvasHeight;

// RENDERER
	renderer = new THREE.WebGLRenderer( { antialias: true } );
	renderer.gammaInput = true;
	renderer.gammaOutput = true;
	renderer.setSize(canvasWidth, canvasHeight);
	renderer.setClearColorHex( 0xFFFFFF, 1.0 );

// 攝影機：Y 上、X 右、Z 上
	camera = new THREE.PerspectiveCamera( 1, canvasRatio, 50, 150 );
	camera.position.set( 0.5, 0.5, 100 );

// 控制
	cameraControls = new THREE.OrbitAndPanControls(camera, renderer.domElement);
	cameraControls.target.set(0.5,0.5,0);
}

function addToDOM() {
	var container = document.getElementById('container');
	var canvas = container.getElementsByTagName('canvas');
	if (canvas.length>0) {
		container.removeChild(canvas[0]);
	}
	container.appendChild( renderer.domElement );
}

function animate() {
	window.requestAnimationFrame(animate);
	render();
}

function render() {
	var delta = clock.getDelta();
	cameraControls.update(delta);

renderer.render(scene, camera);
}

function setupGui() {
	effectController = {
		alpha: 0.7,
		sred:   0xE5/255,
		sgreen: 0x33/255,
		sblue:  0x19/155,

dred:   0xE5/255,
		dgreen: 0xE5/255,
		dblue:  0x66/255
	};
}