Course-WebGL/index.html at master · Wulonghua/Course-WebGL · GitHub

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<!doctype html>
<html>
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="chrome=1">
    <title>Course-webgl by Wulonghua</title>

    <link rel="stylesheet" href="stylesheets/styles.css">
    <link rel="stylesheet" href="stylesheets/github-light.css">
    <link rel="icon" href="data:;base64,=">
    <script src="javascripts/scale.fix.js"></script>
    <script type="text/javascript" src="javascripts/glMatrix-0.9.5.min.js"></script>
    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
    <script id="shader-fs" type="x-shader/x-fragment">
        precision mediump float;
        precision mediump int;

        uniform mat4 uV2WMatrix;  // eye to world

        uniform vec4 light_pos;
        uniform vec4 ambient_coef;
        uniform vec4 diffuse_coef;
        uniform vec4 specular_coef;
        uniform float mat_shininess;

        uniform vec4 light_ambient;
        uniform vec4 light_diffuse;
        uniform vec4 light_specular;

        uniform int use_texture;
        uniform sampler2D myTexture;
        uniform samplerCube cubeMap;

        uniform sampler2D permutation_sampler;
        uniform sampler2D gradient_sampler;

        varying vec4 eye_pos;
        varying vec3 v_normal;
        varying highp vec2 FtexCoord;
        varying vec3 noise_seed;

        float fade(float t)
        {
            return (t*(t*6.0-15.0)+10.0)*t*t*t;
        }

        float lerp(float t, float a, float b){
            return mix(a, b, t);
        }

        float grad(float hash, vec3 pos){
            return dot(texture2D(gradient_sampler, vec2(hash,0)).rgb, pos);
        }

        float permute(float x){
            return texture2D(permutation_sampler, vec2(x / 256.0, 0)).r * 256.0;
        }

        float generatePerlinNoise(vec3 pos){
            vec3 pos_t = mod(floor(pos),256.0);
            float X = pos_t.x;
            float Y = pos_t.y;
            float Z = pos_t.z;
            float x = pos.x - floor(pos.x);
            float y = pos.y - floor(pos.y);
            float z = pos.z - floor(pos.z);
            float u = fade(x);
            float v = fade(y);
            float w = fade(z);
            float A  = permute(X)+Y;
            float AA = permute(A)+Z;
            float AB = permute(A+1.0)+Z;
            float B  = permute(X+1.0)+Y;
            float BA = permute(B)+Z;
            float BB = permute(B+1.0)+Z;

            return lerp(w, lerp(v, lerp(u, grad(permute(AA), vec3(x  , y  , z)),
                                           grad(permute(BA), vec3(x-1.0, y  , z))),
                                   lerp(u, grad(permute(AB), vec3(x  , y-1.0, z)),
                                           grad(permute(BB), vec3(x-1.0, y-1.0, z)))),
                           lerp(v, lerp(u, grad(permute(AA+1.0), vec3(x  , y  , z-1.0)),
                                           grad(permute(BA+1.0), vec3(x-1.0, y  , z-1.0))),
                                   lerp(u, grad(permute(AB+1.0), vec3(x  , y-1.0, z-1.0)),
                                           grad(permute(BB+1.0), vec3(x-1.0, y-1.0, z-1.0)))));
        }

        void main(void) {
        vec4 texcolor;
        vec3 view_vector, ref;
        vec4 env_color;

        vec4 light_pos_in_eye = light_pos;

        // light vector L = l-p
        vec3 light_vector = normalize(vec3(light_pos_in_eye - eye_pos));

        // eye vector V = e-p, where e is (0,0,0)
        vec3 eye_vector = normalize(-vec3(eye_pos));

        vec4 ambient = ambient_coef * light_ambient;
        float ndotl = max(dot(v_normal, light_vector), 0.0);

        vec4 diffuse = diffuse_coef * light_diffuse* ndotl;

        vec3 R = normalize(2.0 * ndotl *v_normal-light_vector);
        float rdotv = max(dot(R, eye_vector), 0.0);


        vec4 specular;
        if (ndotl>0.0)
        specular = specular_coef* light_specular*pow(rdotv, mat_shininess);
        else
        specular = vec4(0.0,0.0,0.0,1);

        if ( use_texture == 1 ) {
            texcolor = texture2D(myTexture, FtexCoord);
            gl_FragColor = texcolor *(ambient+diffuse) +specular;
        }
        else if (use_texture == 2) {
            texcolor = texture2D(myTexture, FtexCoord);
            float noise = generatePerlinNoise(noise_seed);
            gl_FragColor = texcolor *(ambient+diffuse) + vec4(noise,noise,0.0,1.0);
        }
        else if (use_texture == 3){
            view_vector = normalize(vec3(vec4(0,0,0,1)-eye_pos));
            ref = normalize(reflect(-view_vector, v_normal));  // in eye space
            ref = vec3(uV2WMatrix*vec4(ref,0));   // convert to world space
            env_color = textureCube(cubeMap, ref);
            gl_FragColor = env_color;
        }
        else if(use_texture ==4){
            float ratio = 1.00 / 1.52;
            view_vector = normalize(vec3(vec4(0,0,0,1)-eye_pos));
            ref = refract(-view_vector, normalize(v_normal), ratio);
            ref = vec3(uV2WMatrix*vec4(ref,0));   // convert to world space
            env_color = textureCube(cubeMap, ref);
            gl_FragColor = env_color;
        }
        else gl_FragColor = ambient+diffuse+specular;

        }

    </script>
    <!--  ************** Vertex Shader ************* -->
    <script id="shader-vs" type="x-shader/x-vertex">
        precision mediump float;
        precision mediump int;

        attribute vec3 aVertexPosition;
        attribute vec3 aVertexNormal;
        attribute vec2 aVertexTexCoords;

        uniform mat4 uMMatrix;
        uniform mat4 uVMatrix;
        uniform mat4 uPMatrix;
        uniform mat4 uNMatrix;

        varying vec4 eye_pos;  //vertex position in eye space
        varying vec3 v_normal;  // vertex normal
        varying vec3 noise_seed;
        varying highp vec2 FtexCoord;

        void main(void) {

        // transform normal from local to eye space: normal matrix is the inverse transpose of the modelview matrix
        v_normal =normalize(vec3(uNMatrix*vec4(aVertexNormal,0.0)));

        // transform the vertex position to eye space
        eye_pos = uVMatrix*uMMatrix*vec4(aVertexPosition, 1.0);

        noise_seed = aVertexPosition * 8.0;

        FtexCoord = aVertexTexCoords;

        gl_Position = uPMatrix*uVMatrix*uMMatrix*vec4(aVertexPosition, 1.0);

        }

    </script>

    <script id="shader-vs-skybox" type="x-shader/x-vertex">
       uniform mat4 uMMatrix;
       uniform mat4 uVMatrix;
       uniform mat4 uPMatrix;
       attribute vec3 aVertexPosition;
       varying vec3 vCoords;
       void main() {
          gl_Position = uPMatrix*uVMatrix*uMMatrix*vec4(aVertexPosition, 1.0);
          vCoords = aVertexPosition;
       }

    </script>
    <script id="shader-fs-skybox" type="x-shader/x-fragment">
       precision mediump float;
       varying vec3 vCoords;
       uniform samplerCube cubeMap;
       void main() {
            gl_FragColor = textureCube(cubeMap, vCoords);
       }

    </script>

    <script type="text/javascript" src="javascripts/shaders_setup.js"></script>
    <script type="text/javascript" src="javascripts/trackball-rotator.js"></script>
    <script type="text/javascript" src="javascripts/lab5.js"></script>

</head>
<body onload="webGLStart();">
<div class="wrapper">
    <header>
        <h1 class="header">Course-WebGL</h1>
        <p class="header"></p>

        <ul>
            <li class="download"><a class="buttons" href="https://github.com/Wulonghua/Course-WebGL/zipball/master">Download
                ZIP</a></li>
            <li class="download"><a class="buttons" href="https://github.com/Wulonghua/Course-WebGL/tarball/master">Download
                TAR</a></li>
            <li><a class="buttons github" href="https://github.com/Wulonghua/Course-WebGL">View On GitHub</a></li>
        </ul>

        <p class="header">This project is maintained by <a class="header name" href="https://github.com/Wulonghua">Wulonghua</a>
        </p>


    </header>
    <section>
        <h3>
            <a id="welcome-to-github-pages" class="anchor" href="#welcome-to-github-pages" aria-hidden="true"><span
                    aria-hidden="true" class="octicon octicon-link"></span></a>
            Real Time Rendering Demo
        </h3>

        <canvas id="lab5-canvas" style="border:none;" width="650" height="650"></canvas>

        <h4> Texture:  </h4>
        <button onclick="texture(0)"> NO  </button>
        <button onclick="texture(1)"> Regular </button>
        <button onclick="texture(2)"> Perlin Noise </button>
        <button onclick="texture(3)"> Reflection </button>
        <button onclick="texture(4)"> Refraction </button>

        <div>
            <h4>
                Click on the left mouse button and move the coursor to rotate
            </h4>
            <button onclick="redraw()"> Go Back! </button>
        </div>


    </section>
    <footer>
        <p>
            <small>Hosted on <a href="https://pages.github.com">GitHub Pages</a> using the Dinky theme</small>
        </p>
    </footer>
</div>
<!--[if !IE]>
<script>fixScale(document);</script><![endif]-->

</body>
</html>