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HTML 

              
                <body>
<script type="x-shader/x-vertex" id="birdVert">

            attribute float startFrameId;

            uniform float iGlobalTime;
            uniform vec2 iResolution;
            uniform vec2 iMouse;

            varying vec2 vUV;
            varying mat2 vUVRot;
            varying float vFrameId;

            void main()
            {
                vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );

                vec2 vel = 2.0 * ( iMouse / iResolution - vec2( 0.5 ) );
                vUV = vec2( vel.x * 0.5 + 0.5, vel.y * 0.5 + 0.5 );
                vUV = floor( vUV * 11.0 ) / 11.0;
                float gridRotation = atan( vUV.y - 0.5, vUV.x - 0.5 );
                vUV += 0.5 / 11.0;

                float rotation = atan( vel.y, vel.x ) - gridRotation;
                float s = sin( rotation );
                float c = cos( rotation );
                vUVRot = mat2( c, -s, s, c );

                gl_PointSize = 64.0;

                vFrameId = floor( mod( startFrameId + iGlobalTime, 9.0 ) );
                gl_Position = projectionMatrix * mvPosition;
            }
        </script>
 <script type="x-shader/x-fragment" id="birdFrag">
            uniform sampler2D texturesBird[ 9 ];

            varying vec2 vUV;
            varying mat2 vUVRot;
            varying vec2 vMouse;
            varying float vFrameId;

            void main()
            {
                vec2 uv = 0.9 * vec2( 1.0 / 11.0 ) * ( gl_PointCoord - 0.5 ) * vUVRot + vUV;
                int id = int( vFrameId );

                vec4 col;
                if ( id == 0 ) { col = texture2D( texturesBird[ 0 ], uv ); }
                else if ( id == 1 ) { col = texture2D( texturesBird[ 1 ], uv ); }
                else if ( id == 2 ) { col = texture2D( texturesBird[ 2 ], uv ); }
                else if ( id == 3 ) { col = texture2D( texturesBird[ 3 ], uv ); }
                else if ( id == 4 ) { col = texture2D( texturesBird[ 4 ], uv ); }
                else if ( id == 5 ) { col = texture2D( texturesBird[ 5 ], uv ); }
                else if ( id == 6 ) { col = texture2D( texturesBird[ 6 ], uv ); }
                else if ( id == 7 ) { col = texture2D( texturesBird[ 7 ], uv ); }
                else if ( id == 8 ) { col = texture2D( texturesBird[ 8 ], uv ); }

                gl_FragColor = col;
            }
        </script>
</body>
!

CSS 

              
                * {
	margin: 0;
	padding: 0;
}
!

JS 

              
                // Grid of Birds
//
// Created by XORXOR, 2016
// Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)

var renderer, camera, scene;

var birdTextures = [];
var uniforms;
var startTime;

init();

function init()
{
	var container = document.createElement( 'div' );
	document.body.appendChild( container );

	loader = new THREE.TextureLoader();
	birdTextures[ 0 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-00.png' );
	birdTextures[ 1 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-01.png' );
	birdTextures[ 2 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-02.png' );
	birdTextures[ 3 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-03.png' );
	birdTextures[ 4 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-04.png' );
	birdTextures[ 5 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-05.png' );
	birdTextures[ 6 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-06.png' );
	birdTextures[ 7 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-07.png' );
	birdTextures[ 8 ] = loader.load( 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/896175/crow-08.png' );
	for ( var i = 0; i <= 8; i++ )
	{
		birdTextures[ i ].flipY = false;
	}

	startTime = Date.now();

	scene = new THREE.Scene();

	renderer = new THREE.WebGLRenderer( { antialias: true } );
	renderer.setSize( window.innerWidth, window.innerHeight );
	renderer.setClearColor( 0xffffff );
	container.appendChild( renderer.domElement );

	onWindowResize();

	window.addEventListener( 'resize', onWindowResize, false );
	window.addEventListener( 'mousemove', mouseMove );

	render();
}

function addBirds()
{
	var oldBirds = scene.getObjectByName( "birds" );
	scene.remove( oldBirds );

	var width = window.innerWidth;
	var height = window.innerHeight;

	var size = 64.0;
	var wNum = Math.floor( width / size ) + 1;
	var hNum = Math.floor( height / size ) + 1;

	var numBirds = wNum * hNum;

	geometry = new THREE.BufferGeometry();
	var positions = new Float32Array( numBirds * 3 );
	var startFrameIds = new Float32Array( numBirds );

	var yp = size * 0.5;
	for ( var y = 0, i = 0, i3 = 0; y < hNum; y++ )
	{
		var xp = size * 0.5;
		for ( var x = 0; x < wNum; x++, i++, i3 += 3 )
		{
			positions[ i3 + 0 ] = xp;
			positions[ i3 + 1 ] = yp;
			positions[ i3 + 2 ] = 0.0;
			startFrameIds[ i ] = ( x + y ) % 9.0;

			xp += size;
		}
		yp += size;
	}

	geometry.addAttribute( 'position', new THREE.BufferAttribute( positions, 3 ) );
	geometry.addAttribute( 'startFrameId', new THREE.BufferAttribute( startFrameIds, 1 ) );

	uniforms = { texturesBird: { value: birdTextures },
				 iGlobalTime: { type: "f", value: 0.0 },
				 iResolution: { type: "v2", value: new THREE.Vector2() },
				 iMouse: { type: "v2", value: new THREE.Vector2() } };

	var shaderMaterial = new THREE.ShaderMaterial(
		{
			uniforms: uniforms,
			vertexShader: document.getElementById( 'birdVert' ).textContent,
			fragmentShader: document.getElementById( 'birdFrag' ).textContent,
			depthTest: false,
			transparent: true
		} );

	particles = new THREE.Points( geometry, shaderMaterial );
	particles.name = "birds";
	scene.add( particles );
}

function render()
{
	var currentTime = Date.now();
	uniforms.iGlobalTime.value = ( currentTime - startTime ) * 0.01;

	requestAnimationFrame( render );
	renderer.render( scene, camera );
}

function onWindowResize()
{
	addBirds();

	uniforms.iResolution.value.x = window.innerWidth;
	uniforms.iResolution.value.y = window.innerHeight;

	camera = new THREE.OrthographicCamera( 0.0, window.innerWidth,
										   window.innerHeight, 0.0, 1.0, 1000.0 );
	camera.position.set( 0.0, 0.0, 5.0 );
	renderer.setSize( window.innerWidth, window.innerHeight );
}

function mouseMove( event )
{
	uniforms.iMouse.value.x = event.clientX;
	uniforms.iMouse.value.y = window.innerHeight - event.clientY;
}
!
999px

Console