icg-hw1/index_Gouraud.html at master · ntu-homeworks/icg-hw1 · GitHub

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<!DOCTYPE html>
<html>
<head>
    <title>ICG WebGL &mdash; HW1</title>
    <meta name="author" content="Chih-Yung Liang">
</head>

<script src="js/glMatrix-0.9.5.min.js"></script>
<script src="js/webgl-utils.js"></script>
<script src="js/gl.js"></script>
<script src="js/common.js"></script>

<script id="fragmentShader" type="x-shader/x-fragment">
    //per-fragment-lighting-fs

    precision mediump float;
    varying vec4 fragcolor;
    void main(void) {
        gl_FragColor = fragcolor;
    }
</script>

<script id="vertexShader" type="x-shader/x-vertex">
    //per-fragment-lighting-vs

    attribute vec3 aVertexPosition;
    attribute vec3 aVertexNormal;
    attribute vec2 aTextureCoord;

    uniform mat4 uMVMatrix;
    uniform mat4 uPMatrix;
    uniform mat3 uNMatrix;

	varying vec4 fragcolor;

	uniform float uMaterialShininess;

    uniform vec3 uAmbientColor;
    uniform vec3 uPointLightingLocation;
    uniform vec3 uPointLightingSpecularColor;
    uniform vec3 uPointLightingDiffuseColor;

    uniform sampler2D uSampler;

    void main(void) {
        //vPosition = uMVMatrix * vec4(aVertexPosition, 1.0);
        gl_Position = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1.0);


		vec3 lightWeighting;
        vec3 lightDirection = normalize(uPointLightingLocation - (uMVMatrix * vec4(aVertexPosition, 1.0)).xyz);
        vec3 normal = normalize(uNMatrix * aVertexNormal);

        float specularLightWeighting = 0.0;

        vec3 eyeDirection = normalize(-(uMVMatrix * vec4(aVertexPosition, 1.0)).xyz);
        vec3 reflectionDirection = reflect(-lightDirection, normal);

        specularLightWeighting = pow(max(dot(reflectionDirection, eyeDirection), 0.0), uMaterialShininess);


        float diffuseLightWeighting = max(dot(normal, lightDirection), 0.0);
         lightWeighting = uAmbientColor
            + uPointLightingSpecularColor * specularLightWeighting
            + uPointLightingDiffuseColor * diffuseLightWeighting;

        vec4 fragmentColor;
		fragmentColor = texture2D(uSampler, vec2(aTextureCoord.s, aTextureCoord.t));
		fragcolor = vec4(fragmentColor.rgb * lightWeighting, fragmentColor.a);;


    }
</script>

<script type="text/javascript">
var teapot;
var teapotAngle = 180;

function tick() {
    teapot.transform.rotate.angle = teapotAngle;
    teapot.attributes.ambientColorUniform = [
        parseFloat(document.getElementById('ambientR').value),
        parseFloat(document.getElementById('ambientG').value),
        parseFloat(document.getElementById('ambientB').value)
    ];
    teapot.attributes.pointLightingLocationUniform = [
        parseFloat(document.getElementById('lightPositionX').value),
        parseFloat(document.getElementById('lightPositionY').value),
        parseFloat(document.getElementById('lightPositionZ').value)
    ];
    teapot.attributes.pointLightingSpecularColorUniform = [
        parseFloat(document.getElementById('specularR').value),
        parseFloat(document.getElementById('specularG').value),
        parseFloat(document.getElementById('specularB').value)
    ];
    teapot.attributes.pointLightingDiffuseColorUniform = [
        parseFloat(document.getElementById('diffuseR').value),
        parseFloat(document.getElementById('diffuseG').value),
        parseFloat(document.getElementById('diffuseB').value)
    ];
    teapot.attributes.materialShininessUniform = parseFloat(document.getElementById('shininess').value);

    requestAnimFrame(tick);
    gl.drawScene();
    animate();
}

function webGLStart() {
    var canvas = document.getElementById("ICG-canvas");
    gl.initGL(canvas);

    gl.initShaders([
        document.getElementById('fragmentShader'),
        document.getElementById('vertexShader')
    ], {
        uniforms: {
            pMatrixUniform: "uPMatrix",
            mvMatrixUniform: "uMVMatrix",
            nMatrixUniform: "uNMatrix",
            samplerUniform: "uSampler",
            materialShininessUniform: "uMaterialShininess",

            ambientColorUniform: "uAmbientColor",
            pointLightingLocationUniform: "uPointLightingLocation",
            pointLightingSpecularColorUniform: "uPointLightingSpecularColor",
            pointLightingDiffuseColorUniform: "uPointLightingDiffuseColor"
        },
        vertexAttrs: {
            vertexPositionAttribute: "aVertexPosition",
            vertexNormalAttribute: "aVertexNormal",
            textureCoordAttribute: "aTextureCoord"
        }
    });

    galvanizedImg = new Image();
    galvanizedImg.onload = function () {
        gl.addTexture("galvanizedTexture", galvanizedImg);
    }
    galvanizedImg.src = "textures/galvanizedTexture.jpg";

    teapot = loadTeapot();

    tick();
}
</script>


<style type="text/css">
    #loadingtext {
        position:absolute;
        top:250px;
        left:150px;
        font-size:2em;
        color: white;
    }
</style>

<body onload="webGLStart();">
    <canvas id="ICG-canvas" style="border: none;" width="800" height="600"></canvas>
    <br/>


	Shading:
    <select id="shading" onchange="window.location='index_' + this.value + '.html';">
        <option value="Flat">Flat Shading</option>
        <option value="Phong"> Phong Shading</option>
        <option selected value="Gouraud">Gouraud Shading</option>
    </select>
    <br/>
    <table style="border: 0; padding: 10px;">
        <tr>
            <td><b>Material:</b>
            <td><input type="text" id="shininess" value="32.0" />
        </tr>
		<tr>
            <td><b>Point Light Location:</b>
            <td>X: <input type="text" id="lightPositionX" value="-10.0" />
            <td>Y: <input type="text" id="lightPositionY" value="4.0" />
            <td>Z: <input type="text" id="lightPositionZ" value="-20.0" />
        </tr>
        <tr>
            <td><b>Specular Colour:</b>
            <td>R: <input type="text" id="specularR" value="0.8" />
            <td>G: <input type="text" id="specularG" value="0.8" />
            <td>B: <input type="text" id="specularB" value="0.8" />
        </tr>
        <tr>
            <td><b>Diffuse Colour:</b>
            <td>R: <input type="text" id="diffuseR" value="0.8" />
            <td>G: <input type="text" id="diffuseG" value="0.8" />
            <td>B: <input type="text" id="diffuseB" value="0.8" />
        </tr>
		<tr>
            <td><b>Ambient Light Colour:</b>
            <td>R: <input type="text" id="ambientR" value="0.2" />
            <td>G: <input type="text" id="ambientG" value="0.2" />
            <td>B: <input type="text" id="ambientB" value="0.2" />
        </tr>
    </table>
</body>
</html>