Emanuele-Spatola · August 7, 2018 14:27
diff --git a/WebGL360Video.html b/WebGL360Video.html
 <!DOCTYPE HTML> 
 <html> 
 	<head> 
 		<meta charset="utf-8"> 
 		<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
 		<title>Simple WebGL/GLSL video panorama viewer</title> 
 		
 		<style> 
 			body {
 				background-color: #000000;
 				margin: 0px;
 				overflow: hidden;
 			}
 			video {
 				display: none;
 			}
 		</style> 
 	</head> 
 	<body> 
 
 		<canvas></canvas>
 		<video></video>
 
 		<script id="vs" type="x-shader/vertex"> 
 			attribute vec3 position;
 
 			void main() {
 				gl_Position = vec4( position, 1.0 );
 			}
 		</script> 
 
 		<script id="fs" type="x-shader/fragment"> 
 			uniform vec2 resolution;
 			uniform sampler2D texture;
 			
 			uniform float fov;
 			uniform float yaw; 
 			uniform float pitch;
 
 			const float M_PI = 3.141592653589793238462643;
 			const float M_TWOPI = 6.283185307179586476925286;
 
 			mat3 rotationMatrix(vec2 euler)
 			{
 				vec2 se = sin(euler);
 				vec2 ce = cos(euler);
 				
 				return 	mat3(ce.x, 0, -se.x,	0, 1, 0,		se.x, 0, ce.x) * 
 						mat3(1, 0, 0,			0, ce.y, -se.y,	0, se.y, ce.y);
 			}

 			vec3 toCartesian( vec2 st )
 			{
 				return normalize(vec3(st.x, st.y, 0.5 / tan(0.5 * radians(fov))));
 			}

 			vec2 toSpherical(vec3 cartesianCoord)
 			{
 				vec2 st = vec2(
 					atan(cartesianCoord.x, cartesianCoord.z),
 					acos(cartesianCoord.y)
 				);
 				if(st.x < 0.0)
 					st.x += M_TWOPI;
 				
 				return st;
 			}

 			void main(void)
 			{
 				vec2 sphericalCoord = gl_FragCoord.xy / resolution - vec2(0.5);
 				sphericalCoord.y *= -resolution.y / resolution.x;

 				vec3 cartesianCoord = rotationMatrix(radians(vec2(yaw + 180., -pitch))) * toCartesian(sphericalCoord);
 				
 				gl_FragColor = texture2D(texture, toSpherical( cartesianCoord )/vec2(M_TWOPI, M_PI));
 			}
 		</script> 
 
 		<script> 
 			/**
 			 * Provides requestAnimationFrame in a cross browser way.
 			 * paulirish.com/2011/requestanimationframe-for-smart-animating/
 			 */
 			window.requestAnimationFrame = window.requestAnimationFrame || ( function() {
 				return  window.webkitRequestAnimationFrame ||
 						window.mozRequestAnimationFrame ||
 						window.oRequestAnimationFrame ||
 						window.msRequestAnimationFrame ||
 						function( callback, element ) {
 							window.setTimeout( callback, 1000 / 60 );
 						};
 			})();

 
 			var canvas, 
 				gl, 
 				video, video_texture, video_started = false,
 				buffer, 
 				vertex_shader, fragment_shader, currentProgram,
 				vertex_position, 
 				parameters = {	start_time	: new Date().getTime(), 
 								time		: 0, 
 								screenWidth	: 0, 
 								screenHeight: 0 },
 				currentlyDragging = false,
 				currentDragX = 0, currentDragY = 0,
 				startDragX = 0, startDragY = 0,
 				xSpeed = 0, ySpeed = 0,
 				yaw = 0, pitch = 0, fov = 80;

 				
 			init("video.ogv", "preview.jpg");
 			animate();
 
 			function init( video_url, preview_url ) {
 				video = document.querySelector( 'video' );

 				video.addEventListener("canplaythrough", startVideo, true);
 				video.preload = "auto";
 				video.loop = true;
 				video.src = video_url;			
 
 				canvas = document.querySelector( 'canvas' );
 								
 				vertex_shader = document.getElementById('vs').textContent;
 				fragment_shader = document.getElementById('fs').textContent;				
 				
 				// Initialise WebGL
 				try {
 					gl = canvas.getContext( 'experimental-webgl' );
 				} catch( error ) { }
 
 				if ( !gl ) {
 					throw "cannot create webgl context";
 				}
 
 				// Create Vertex buffer (2 triangles)
 				buffer = gl.createBuffer();
 				gl.bindBuffer( gl.ARRAY_BUFFER, buffer );
 				gl.bufferData( gl.ARRAY_BUFFER, new Float32Array( [ - 1.0, - 1.0, 1.0, - 1.0, - 1.0, 1.0, 1.0, - 1.0, 1.0, 1.0, - 1.0, 1.0 ] ), gl.STATIC_DRAW );
 
 				// Create texture for video
 				createTexture( preview_url );
 
 				// Create Program
 				currentProgram = createProgram( vertex_shader, fragment_shader );
 
 				handleResize();
 				window.addEventListener( 'resize', handleResize, false );
 				
 				// Initialise interaction
 				canvas.onmousedown = handleMouseDown;
 				document.onmouseup = handleMouseUp;
 				canvas.onmousemove = handleMouseMove;
 				canvas.ondblclick = handleDoubleClick;				
 			}
 
 
 			function animate() {
 				handleMouse();
 				render();
 				requestAnimationFrame( animate );
 			}
 
 
 			function render() {
 				if ( !currentProgram ) return;
 
 				if( video_started )
 					updateTexture();
 
 				parameters.time = new Date().getTime() - parameters.start_time;
 
 				gl.clear( gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT );
 
 				// Load program into GPU
 				gl.useProgram( currentProgram );
 				
 				gl.bindTexture(gl.TEXTURE_2D, video_texture);
 
 				// Set values to program variables
 				gl.uniform2f( gl.getUniformLocation( currentProgram, 'resolution' ), parameters.screenWidth, parameters.screenHeight );
 				gl.uniform1i( gl.getUniformLocation( currentProgram, 'video' ), 0 );
 
 				gl.uniform1f( gl.getUniformLocation( currentProgram, 'fov' ), 80 );
 				gl.uniform1f( gl.getUniformLocation( currentProgram, 'yaw' ), yaw );
 				gl.uniform1f( gl.getUniformLocation( currentProgram, 'pitch' ), -pitch );				
 
 				// Render geometry
 				gl.bindBuffer( gl.ARRAY_BUFFER, buffer );
 				gl.vertexAttribPointer( vertex_position, 2, gl.FLOAT, false, 0, 0 );
 				gl.enableVertexAttribArray( vertex_position );
 				gl.drawArrays( gl.TRIANGLES, 0, 6 );
 				gl.disableVertexAttribArray( vertex_position );
 			}


 			function createShader( src, type ) {
 				var shader = gl.createShader( type );
 
 				gl.shaderSource( shader, src );
 				gl.compileShader( shader );
 
 				if ( !gl.getShaderParameter( shader, gl.COMPILE_STATUS ) ) {
 					alert( ( type == gl.VERTEX_SHADER ? "VERTEX" : "FRAGMENT" ) + " SHADER:\n" + gl.getShaderInfoLog( shader ) );
 					return null;
 				}
 
 				return shader;
 			}
 			
 			
 			function createProgram( vertex, fragment ) {
 
 				var program = gl.createProgram();
 
 				var vs = createShader( vertex, gl.VERTEX_SHADER );
 				var fs = createShader( '#ifdef GL_ES\nprecision highp float;\n#endif\n\n' + fragment, gl.FRAGMENT_SHADER );
 
 				if ( vs == null || fs == null ) return null;
 
 				gl.attachShader( program, vs );
 				gl.attachShader( program, fs );
 
 				gl.deleteShader( vs );
 				gl.deleteShader( fs );
 
 				gl.linkProgram( program );
 
 				if ( !gl.getProgramParameter( program, gl.LINK_STATUS ) ) {
 					alert( "ERROR:\n" +
 					"VALIDATE_STATUS: " + gl.getProgramParameter( program, gl.VALIDATE_STATUS ) + "\n" +
 					"ERROR: " + gl.getError() + "\n\n" +
 					"- Vertex Shader -\n" + vertex + "\n\n" +
 					"- Fragment Shader -\n" + fragment );
 
 					return null;
 				}
 
 				return program;
 			}
 

 			function createTexture( image_src ) {
 				video_texture = gl.createTexture();
 				video_texture.image = new Image();
 				
 				video_texture.image.onload = function() {
 					gl.bindTexture(gl.TEXTURE_2D, video_texture);
 					gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
 					gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, video_texture.image);
 					gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
 					gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
 					gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
 					gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
 					gl.bindTexture(gl.TEXTURE_2D, null);
 				}

 				video_texture.image.src = image_src;
 			}

 			
 			function updateTexture() {
 				gl.bindTexture(gl.TEXTURE_2D, video_texture);
 				gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
 				gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, video);
 				gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
 				gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
 				gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
 				gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
 				gl.bindTexture(gl.TEXTURE_2D, null);
 			} 				
 			
 			
 			function startVideo() {
 				video.play();
 				video_started = true;
 			}
 			
 			
 			function handleResize( event ) {
 				canvas.width = window.innerWidth;
 				canvas.height = window.innerHeight;
 
 				parameters.screenWidth = canvas.width;
 				parameters.screenHeight = canvas.height;
 
 				gl.viewport( 0, 0, canvas.width, canvas.height );
 			}
 			

 			function handleDoubleClick(event) {
 				var isInFullScreen = (document.fullScreen || document.mozFullScreen || document.webkitIsFullScreen);
 				if(!isInFullScreen) {
 					if (canvas.requestFullscreen) {
 						canvas.requestFullscreen();
 					} else if (canvas.mozRequestFullScreen) {
 						canvas.mozRequestFullScreen();
 					} else if (canvas.webkitRequestFullscreen) {
 						canvas.webkitRequestFullscreen();
 					}			
 				} else {
 					if(document.cancelFullScreen) {
 						document.cancelFullScreen();
 					} else if(document.mozCancelFullScreen) {
 						document.mozCancelFullScreen();
 					} else if(document.webkitCancelFullScreen) {
 						document.webkitCancelFullScreen();
 					}
 				}
 			}
 			

 			function handleMouseDown(event) {
 				startDragX = event.clientX;
 				startDragY = event.clientY;

 				currentDragX = event.clientX;
 				currentDragY = event.clientY;
 				currentlyDragging = true;
 				return false;
 			}

 			
 			function handleMouseUp(event) {
 				currentlyDragging = false;
 				return false;
 			}

 			
 			function handleMouseMove(event) {
 				if(currentlyDragging) {
 					currentDragX = event.clientX;
 					currentDragY = event.clientY;
 				}
 				return false;
 			}
 			
 			
 			function handleMouse() {
 				if (currentlyDragging) {
 					xSpeed = (currentDragX - startDragX) / 100;
 					ySpeed = (currentDragY - startDragY) / 100;	
 				}else {
 					xSpeed *= 0.8;
 					ySpeed *= 0.8;
 				}
 				
 				yaw += xSpeed;
 				pitch += ySpeed;
 			}
 		</script> 
 	</body> 
 </html>
	<!DOCTYPE HTML>
	<html>
	<head>
	<meta charset="utf-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
	<title>Simple WebGL/GLSL video panorama viewer</title>

	<style>
	body {
	background-color: #000000;
	margin: 0px;
	overflow: hidden;
	}
	video {
	display: none;
	}
	</style>
	</head>
	<body>

	<canvas></canvas>
	<video></video>

	<script id="vs" type="x-shader/vertex">
	attribute vec3 position;

	void main() {
	gl_Position = vec4( position, 1.0 );
	}
	</script>

	<script id="fs" type="x-shader/fragment">
	uniform vec2 resolution;
	uniform sampler2D texture;

	uniform float fov;
	uniform float yaw;
	uniform float pitch;

	const float M_PI = 3.141592653589793238462643;
	const float M_TWOPI = 6.283185307179586476925286;

	mat3 rotationMatrix(vec2 euler)
	{
	vec2 se = sin(euler);
	vec2 ce = cos(euler);

	return mat3(ce.x, 0, -se.x, 0, 1, 0, se.x, 0, ce.x) *
	mat3(1, 0, 0, 0, ce.y, -se.y, 0, se.y, ce.y);
	}

	vec3 toCartesian( vec2 st )
	{
	return normalize(vec3(st.x, st.y, 0.5 / tan(0.5 * radians(fov))));
	}

	vec2 toSpherical(vec3 cartesianCoord)
	{
	vec2 st = vec2(
	atan(cartesianCoord.x, cartesianCoord.z),
	acos(cartesianCoord.y)
	);
	if(st.x < 0.0)
	st.x += M_TWOPI;

	return st;
	}

	void main(void)
	{
	vec2 sphericalCoord = gl_FragCoord.xy / resolution - vec2(0.5);
	sphericalCoord.y *= -resolution.y / resolution.x;

	vec3 cartesianCoord = rotationMatrix(radians(vec2(yaw + 180., -pitch))) * toCartesian(sphericalCoord);

	gl_FragColor = texture2D(texture, toSpherical( cartesianCoord )/vec2(M_TWOPI, M_PI));
	}
	</script>

	<script>
	/**
	* Provides requestAnimationFrame in a cross browser way.
	* paulirish.com/2011/requestanimationframe-for-smart-animating/
	*/
	window.requestAnimationFrame = window.requestAnimationFrame \|\| ( function() {
	return window.webkitRequestAnimationFrame \|\|
	window.mozRequestAnimationFrame \|\|
	window.oRequestAnimationFrame \|\|
	window.msRequestAnimationFrame \|\|
	function( callback, element ) {
	window.setTimeout( callback, 1000 / 60 );
	};
	})();


	var canvas,
	gl,
	video, video_texture, video_started = false,
	buffer,
	vertex_shader, fragment_shader, currentProgram,
	vertex_position,
	parameters = { start_time : new Date().getTime(),
	time : 0,
	screenWidth : 0,
	screenHeight: 0 },
	currentlyDragging = false,
	currentDragX = 0, currentDragY = 0,
	startDragX = 0, startDragY = 0,
	xSpeed = 0, ySpeed = 0,
	yaw = 0, pitch = 0, fov = 80;


	init("video.ogv", "preview.jpg");
	animate();

	function init( video_url, preview_url ) {
	video = document.querySelector( 'video' );

	video.addEventListener("canplaythrough", startVideo, true);
	video.preload = "auto";
	video.loop = true;
	video.src = video_url;

	canvas = document.querySelector( 'canvas' );

	vertex_shader = document.getElementById('vs').textContent;
	fragment_shader = document.getElementById('fs').textContent;

	// Initialise WebGL
	try {
	gl = canvas.getContext( 'experimental-webgl' );
	} catch( error ) { }

	if ( !gl ) {
	throw "cannot create webgl context";
	}

	// Create Vertex buffer (2 triangles)
	buffer = gl.createBuffer();
	gl.bindBuffer( gl.ARRAY_BUFFER, buffer );
	gl.bufferData( gl.ARRAY_BUFFER, new Float32Array( [ - 1.0, - 1.0, 1.0, - 1.0, - 1.0, 1.0, 1.0, - 1.0, 1.0, 1.0, - 1.0, 1.0 ] ), gl.STATIC_DRAW );

	// Create texture for video
	createTexture( preview_url );

	// Create Program
	currentProgram = createProgram( vertex_shader, fragment_shader );

	handleResize();
	window.addEventListener( 'resize', handleResize, false );

	// Initialise interaction
	canvas.onmousedown = handleMouseDown;
	document.onmouseup = handleMouseUp;
	canvas.onmousemove = handleMouseMove;
	canvas.ondblclick = handleDoubleClick;
	}


	function animate() {
	handleMouse();
	render();
	requestAnimationFrame( animate );
	}


	function render() {
	if ( !currentProgram ) return;

	if( video_started )
	updateTexture();

	parameters.time = new Date().getTime() - parameters.start_time;

	gl.clear( gl.COLOR_BUFFER_BIT \| gl.DEPTH_BUFFER_BIT );

	// Load program into GPU
	gl.useProgram( currentProgram );

	gl.bindTexture(gl.TEXTURE_2D, video_texture);

	// Set values to program variables
	gl.uniform2f( gl.getUniformLocation( currentProgram, 'resolution' ), parameters.screenWidth, parameters.screenHeight );
	gl.uniform1i( gl.getUniformLocation( currentProgram, 'video' ), 0 );

	gl.uniform1f( gl.getUniformLocation( currentProgram, 'fov' ), 80 );
	gl.uniform1f( gl.getUniformLocation( currentProgram, 'yaw' ), yaw );
	gl.uniform1f( gl.getUniformLocation( currentProgram, 'pitch' ), -pitch );

	// Render geometry
	gl.bindBuffer( gl.ARRAY_BUFFER, buffer );
	gl.vertexAttribPointer( vertex_position, 2, gl.FLOAT, false, 0, 0 );
	gl.enableVertexAttribArray( vertex_position );
	gl.drawArrays( gl.TRIANGLES, 0, 6 );
	gl.disableVertexAttribArray( vertex_position );
	}


	function createShader( src, type ) {
	var shader = gl.createShader( type );

	gl.shaderSource( shader, src );
	gl.compileShader( shader );

	if ( !gl.getShaderParameter( shader, gl.COMPILE_STATUS ) ) {
	alert( ( type == gl.VERTEX_SHADER ? "VERTEX" : "FRAGMENT" ) + " SHADER:\n" + gl.getShaderInfoLog( shader ) );
	return null;
	}

	return shader;
	}


	function createProgram( vertex, fragment ) {

	var program = gl.createProgram();

	var vs = createShader( vertex, gl.VERTEX_SHADER );
	var fs = createShader( '#ifdef GL_ES\nprecision highp float;\n#endif\n\n' + fragment, gl.FRAGMENT_SHADER );

	if ( vs == null \|\| fs == null ) return null;

	gl.attachShader( program, vs );
	gl.attachShader( program, fs );

	gl.deleteShader( vs );
	gl.deleteShader( fs );

	gl.linkProgram( program );

	if ( !gl.getProgramParameter( program, gl.LINK_STATUS ) ) {
	alert( "ERROR:\n" +
	"VALIDATE_STATUS: " + gl.getProgramParameter( program, gl.VALIDATE_STATUS ) + "\n" +
	"ERROR: " + gl.getError() + "\n\n" +
	"- Vertex Shader -\n" + vertex + "\n\n" +
	"- Fragment Shader -\n" + fragment );

	return null;
	}

	return program;
	}


	function createTexture( image_src ) {
	video_texture = gl.createTexture();
	video_texture.image = new Image();

	video_texture.image.onload = function() {
	gl.bindTexture(gl.TEXTURE_2D, video_texture);
	gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
	gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, video_texture.image);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
	gl.bindTexture(gl.TEXTURE_2D, null);
	}

	video_texture.image.src = image_src;
	}


	function updateTexture() {
	gl.bindTexture(gl.TEXTURE_2D, video_texture);
	gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
	gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, video);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
	gl.bindTexture(gl.TEXTURE_2D, null);
	}


	function startVideo() {
	video.play();
	video_started = true;
	}


	function handleResize( event ) {
	canvas.width = window.innerWidth;
	canvas.height = window.innerHeight;

	parameters.screenWidth = canvas.width;
	parameters.screenHeight = canvas.height;

	gl.viewport( 0, 0, canvas.width, canvas.height );
	}


	function handleDoubleClick(event) {
	var isInFullScreen = (document.fullScreen \|\| document.mozFullScreen \|\| document.webkitIsFullScreen);
	if(!isInFullScreen) {
	if (canvas.requestFullscreen) {
	canvas.requestFullscreen();
	} else if (canvas.mozRequestFullScreen) {
	canvas.mozRequestFullScreen();
	} else if (canvas.webkitRequestFullscreen) {
	canvas.webkitRequestFullscreen();
	}
	} else {
	if(document.cancelFullScreen) {
	document.cancelFullScreen();
	} else if(document.mozCancelFullScreen) {
	document.mozCancelFullScreen();
	} else if(document.webkitCancelFullScreen) {
	document.webkitCancelFullScreen();
	}
	}
	}


	function handleMouseDown(event) {
	startDragX = event.clientX;
	startDragY = event.clientY;

	currentDragX = event.clientX;
	currentDragY = event.clientY;
	currentlyDragging = true;
	return false;
	}


	function handleMouseUp(event) {
	currentlyDragging = false;
	return false;
	}


	function handleMouseMove(event) {
	if(currentlyDragging) {
	currentDragX = event.clientX;
	currentDragY = event.clientY;
	}
	return false;
	}


	function handleMouse() {
	if (currentlyDragging) {
	xSpeed = (currentDragX - startDragX) / 100;
	ySpeed = (currentDragY - startDragY) / 100;
	}else {
	xSpeed *= 0.8;
	ySpeed *= 0.8;
	}

	yaw += xSpeed;
	pitch += ySpeed;
	}
	</script>
	</body>
	</html>