hcccc · November 22, 2013 11:13
diff --git a/gistfile1.txt b/gistfile1.txt
 <html>

 <head>
 <title>Learning WebGL &mdash; lesson 1</title>
 <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">

 <script type="text/javascript" src="glMatrix-0.9.5.min.js"></script>

 <script id="shader-fs" type="x-shader/x-fragment">
    precision mediump float;

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

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

    uniform mat4 uMVMatrix;
    uniform mat4 uPMatrix;

    void main(void) {
        gl_Position = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1.0);
    }
 </script>


 <script type="text/javascript">

    var gl;
    function initGL(canvas) {
        try {
            gl = canvas.getContext("experimental-webgl");
            gl.viewportWidth = canvas.width;
            gl.viewportHeight = canvas.height;
        } catch (e) {
        }
        if (!gl) {
            alert("Could not initialise WebGL, sorry :-(");
        }
    }


    function getShader(gl, id) {
        var shaderScript = document.getElementById(id);
        if (!shaderScript) {
            return null;
        }

        var str = "";
        var k = shaderScript.firstChild;
        while (k) {
            if (k.nodeType == 3) {
                str += k.textContent;
            }
            k = k.nextSibling;
        }

        var shader;
        if (shaderScript.type == "x-shader/x-fragment") {
            shader = gl.createShader(gl.FRAGMENT_SHADER);
        } else if (shaderScript.type == "x-shader/x-vertex") {
            shader = gl.createShader(gl.VERTEX_SHADER);
        } else {
            return null;
        }

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

        if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
            alert(gl.getShaderInfoLog(shader));
            return null;
        }

        return shader;
    }


    var shaderProgram;

    function initShaders() {
        var fragmentShader = getShader(gl, "shader-fs");
        var vertexShader = getShader(gl, "shader-vs");

        shaderProgram = gl.createProgram();
        gl.attachShader(shaderProgram, vertexShader);
        gl.attachShader(shaderProgram, fragmentShader);
        gl.linkProgram(shaderProgram);

        if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
            alert("Could not initialise shaders");
        }

        gl.useProgram(shaderProgram);

        shaderProgram.vertexPositionAttribute = gl.getAttribLocation(shaderProgram, "aVertexPosition");
        gl.enableVertexAttribArray(shaderProgram.vertexPositionAttribute);

        shaderProgram.pMatrixUniform = gl.getUniformLocation(shaderProgram, "uPMatrix");
        shaderProgram.mvMatrixUniform = gl.getUniformLocation(shaderProgram, "uMVMatrix");
    }


    var mvMatrix = mat4.create();
    var pMatrix = mat4.create();

    function setMatrixUniforms() {
        gl.uniformMatrix4fv(shaderProgram.pMatrixUniform, false, pMatrix);
        gl.uniformMatrix4fv(shaderProgram.mvMatrixUniform, false, mvMatrix);
    }



    var triangleVertexPositionBuffer;
    var squareVertexPositionBuffer;

    function initBuffers() {
        squareVertexPositionBuffer = gl.createBuffer();
        gl.bindBuffer(gl.ARRAY_BUFFER, squareVertexPositionBuffer);
        vertices = [
             1.0,  1.0,  0.0,
            -1.0,  1.0,  0.0,
             1.0, -1.0,  0.0,
            -1.0, -1.0,  0.0
        ];
        gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertices), gl.STATIC_DRAW);
        squareVertexPositionBuffer.itemSize = 3;
        squareVertexPositionBuffer.numItems = 4;
    }


    function drawScene() {
        gl.viewport(0, 0, gl.viewportWidth, gl.viewportHeight);
        gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);

        mat4.perspective(45, gl.viewportWidth / gl.viewportHeight, 0.1, 100.0, pMatrix);

        mat4.identity(mvMatrix);

        mat4.translate(mvMatrix, [-1.5, 0.0, -7.0]);
        mat4.translate(mvMatrix, [3.0, 0.0, 0.0]);
        gl.bindBuffer(gl.ARRAY_BUFFER, squareVertexPositionBuffer);
        gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, squareVertexPositionBuffer.itemSize, gl.FLOAT, false, 0, 0);
        setMatrixUniforms();
        gl.drawArrays(gl.TRIANGLE_STRIP, 0, squareVertexPositionBuffer.numItems);
    }



    function webGLStart() {
        var canvas = document.getElementById("lesson01-canvas");
        initGL(canvas);
        initShaders();
        initBuffers();

        gl.clearColor(0.0, 0.0, 0.0, 1.0);
        gl.enable(gl.DEPTH_TEST);

        drawScene();
    }


 </script>


 </head>


 <body onload="webGLStart();">
    <a href="http://learningwebgl.com/blog/?p=28">&lt;&lt; Back to Lesson 1</a><br />

    <canvas id="lesson01-canvas" style="border: none;" width="500" height="500"></canvas>

    <br/>
    <a href="http://learningwebgl.com/blog/?p=28">&lt;&lt; Back to Lesson 1</a><br />
 </body>

 </html>
	<html>

	<head>
	<title>Learning WebGL — lesson 1</title>
	<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">

	<script type="text/javascript" src="glMatrix-0.9.5.min.js"></script>

	<script id="shader-fs" type="x-shader/x-fragment">
	precision mediump float;

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

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

	uniform mat4 uMVMatrix;
	uniform mat4 uPMatrix;

	void main(void) {
	gl_Position = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1.0);
	}
	</script>


	<script type="text/javascript">

	var gl;
	function initGL(canvas) {
	try {
	gl = canvas.getContext("experimental-webgl");
	gl.viewportWidth = canvas.width;
	gl.viewportHeight = canvas.height;
	} catch (e) {
	}
	if (!gl) {
	alert("Could not initialise WebGL, sorry :-(");
	}
	}


	function getShader(gl, id) {
	var shaderScript = document.getElementById(id);
	if (!shaderScript) {
	return null;
	}

	var str = "";
	var k = shaderScript.firstChild;
	while (k) {
	if (k.nodeType == 3) {
	str += k.textContent;
	}
	k = k.nextSibling;
	}

	var shader;
	if (shaderScript.type == "x-shader/x-fragment") {
	shader = gl.createShader(gl.FRAGMENT_SHADER);
	} else if (shaderScript.type == "x-shader/x-vertex") {
	shader = gl.createShader(gl.VERTEX_SHADER);
	} else {
	return null;
	}

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

	if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
	alert(gl.getShaderInfoLog(shader));
	return null;
	}

	return shader;
	}


	var shaderProgram;

	function initShaders() {
	var fragmentShader = getShader(gl, "shader-fs");
	var vertexShader = getShader(gl, "shader-vs");

	shaderProgram = gl.createProgram();
	gl.attachShader(shaderProgram, vertexShader);
	gl.attachShader(shaderProgram, fragmentShader);
	gl.linkProgram(shaderProgram);

	if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
	alert("Could not initialise shaders");
	}

	gl.useProgram(shaderProgram);

	shaderProgram.vertexPositionAttribute = gl.getAttribLocation(shaderProgram, "aVertexPosition");
	gl.enableVertexAttribArray(shaderProgram.vertexPositionAttribute);

	shaderProgram.pMatrixUniform = gl.getUniformLocation(shaderProgram, "uPMatrix");
	shaderProgram.mvMatrixUniform = gl.getUniformLocation(shaderProgram, "uMVMatrix");
	}


	var mvMatrix = mat4.create();
	var pMatrix = mat4.create();

	function setMatrixUniforms() {
	gl.uniformMatrix4fv(shaderProgram.pMatrixUniform, false, pMatrix);
	gl.uniformMatrix4fv(shaderProgram.mvMatrixUniform, false, mvMatrix);
	}



	var triangleVertexPositionBuffer;
	var squareVertexPositionBuffer;

	function initBuffers() {
	squareVertexPositionBuffer = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, squareVertexPositionBuffer);
	vertices = [
	1.0, 1.0, 0.0,
	-1.0, 1.0, 0.0,
	1.0, -1.0, 0.0,
	-1.0, -1.0, 0.0
	];
	gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertices), gl.STATIC_DRAW);
	squareVertexPositionBuffer.itemSize = 3;
	squareVertexPositionBuffer.numItems = 4;
	}


	function drawScene() {
	gl.viewport(0, 0, gl.viewportWidth, gl.viewportHeight);
	gl.clear(gl.COLOR_BUFFER_BIT \| gl.DEPTH_BUFFER_BIT);

	mat4.perspective(45, gl.viewportWidth / gl.viewportHeight, 0.1, 100.0, pMatrix);

	mat4.identity(mvMatrix);

	mat4.translate(mvMatrix, [-1.5, 0.0, -7.0]);
	mat4.translate(mvMatrix, [3.0, 0.0, 0.0]);
	gl.bindBuffer(gl.ARRAY_BUFFER, squareVertexPositionBuffer);
	gl.vertexAttribPointer(shaderProgram.vertexPositionAttribute, squareVertexPositionBuffer.itemSize, gl.FLOAT, false, 0, 0);
	setMatrixUniforms();
	gl.drawArrays(gl.TRIANGLE_STRIP, 0, squareVertexPositionBuffer.numItems);
	}



	function webGLStart() {
	var canvas = document.getElementById("lesson01-canvas");
	initGL(canvas);
	initShaders();
	initBuffers();

	gl.clearColor(0.0, 0.0, 0.0, 1.0);
	gl.enable(gl.DEPTH_TEST);

	drawScene();
	}


	</script>


	</head>


	<body onload="webGLStart();">
	<a href="http://learningwebgl.com/blog/?p=28"><< Back to Lesson 1</a><br />

	<canvas id="lesson01-canvas" style="border: none;" width="500" height="500"></canvas>

	<br/>
	<a href="http://learningwebgl.com/blog/?p=28"><< Back to Lesson 1</a><br />
	</body>

	</html>