WebGLTutorials/index9.php at master · imtumbleweed/WebGLTutorials · GitHub

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<!doctype html>
<html>
<head>
    <title>Tutorial 9 - WebGL Matrix Operations (3D Cube Rotation)</title>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
    <script src = 'http://www.tigrisgames.com/js/jquery.js' type = 'text/javascript'></script>
    <script src = 'http://www.tigrisgames.com/js/ui.js' type = 'text/javascript'></script>
    <script src = 'http://www.tigrisgames.com/fx/gl.js'></script>
    <script src = 'http://www.tigrisgames.com/fx/shaders.js?v=5'></script>
    <script src = 'http://www.tigrisgames.com/fx/primitives.js?v=2'></script>
    <script src = 'http://www.tigrisgames.com/fx/texture.js'></script>
    <script src = 'http://www.tigrisgames.com/fx/matrix.js'></script>
    <script type = "text/javascript">

        /* -- Gl functions -- */

        var canvas = null;
        var gl = null;


        $(document).ready(function() {

            var canvas = document.getElementById('gl');

            gl = GetWebGLContext(canvas);

            if (!gl)
                console.log('Failed to set up WebGL.');

            else { // Load a shader from "shaders" folder

                // Enable depth test
                gl.enable(gl.DEPTH_TEST);
                gl.depthFunc(gl.LESS);

                CreateShadersFromFile( gl );

                LoadTextures();
            }
        });

        // An event that fires when all shader resources finish loading in CreateShadersFromFile
        window.webGLResourcesLoaded = function() {

            console.log("webGLResourcesLoaded(): All WebGL shaders have finished loading!");

            // Specify triangle vertex data:
            var vertices = makeCube();

            var colors = makeCubeColors();

            var uvs = makeCubeTextures();

            var indices = [0];

            for (var i = 0; i < 36; i++)
                indices[i] = i;

            // Create buffer objects for storing triangle vertex and index data
            var vertexbuffer = gl.createBuffer();
            var colorbuffer = gl.createBuffer();
            var texturebuffer = gl.createBuffer();
            var indexbuffer = gl.createBuffer();

            var BYTESIZE = vertices.BYTES_PER_ELEMENT;

            // Bind and create enough room for our data on respective buffers

            // Bind vertex buffer to ARRAY_BUFFER
            gl.bindBuffer(gl.ARRAY_BUFFER, vertexbuffer);
            // Send our vertex data to the buffer using floating point array
            gl.bufferData(gl.ARRAY_BUFFER, vertices, gl.STATIC_DRAW);
            var coords = gl.getAttribLocation(Shader.textureMapProgram, "a_Position");
            gl.vertexAttribPointer(coords, 3, gl.FLOAT, false, 0, 0);
            gl.enableVertexAttribArray(coords); // Enable it
            // We're done; now we have to unbind the buffer
            gl.bindBuffer(gl.ARRAY_BUFFER, null);

            // Bind colorbuffer to ARRAY_BUFFER
            gl.bindBuffer(gl.ARRAY_BUFFER, colorbuffer);
            // Send our vertex data to the buffer using floating point array
            gl.bufferData(gl.ARRAY_BUFFER, colors, gl.STATIC_DRAW);
            var col = gl.getAttribLocation(Shader.textureMapProgram, "a_Color");
            gl.vertexAttribPointer(col, 3, gl.FLOAT, false, 0, 0);
            gl.enableVertexAttribArray(col); // Enable it
            // We're done; now we have to unbind the buffer
            gl.bindBuffer(gl.ARRAY_BUFFER, null);

            // Bind texturebuffer to ARRAY_BUFFER
            gl.bindBuffer(gl.ARRAY_BUFFER, texturebuffer);
            // Send our texture image data to the buffer using floating point array
            gl.bufferData(gl.ARRAY_BUFFER, uvs, gl.STATIC_DRAW);
            var uv = gl.getAttribLocation(Shader.textureMapProgram, "a_Texture");
            gl.vertexAttribPointer(uv, 2, gl.FLOAT, false, 0, 0);
            gl.enableVertexAttribArray(uv); // Enable it
            // We're done; now we have to unbind the buffer (optional but probably a good idea)
            gl.bindBuffer(gl.ARRAY_BUFFER, null);

            // Bind indices to ELEMENT_ARRAY_BUFFER
            gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexbuffer);
            // Send index (indices) data to this buffer
            gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new Uint16Array(indices), gl.STATIC_DRAW);
            // Use our standard shader program for rendering this triangle
            gl.useProgram( Shader.textureMapProgram );

            // Create storage for our matrices
            var Projection = new CanvasMatrix4();
            var ModelView = new CanvasMatrix4();

            var model_angle = 0;

            gl.enable(gl.CULL_FACE);
            gl.cullFace(gl.BACK);
            //gl.enable(gl.DEPTH_TEST);
            //gl.depthFunc(gl.LESS);

            // Start main drawing loop
            var T = setInterval(function() {

                if (!gl)
                    return;

                model_angle += 0.15;

                // Create WebGL canvas
                gl.clearColor(0.0, 0.0, 0.0, 1.0);

                gl.clear(gl.COLOR_BUFFER_BIT);

                // Set active texture to pass into the shader
                gl.activeTexture(gl.TEXTURE0);
                gl.bindTexture(gl.TEXTURE_2D, brick.texture);
                gl.uniform1i(gl.getUniformLocation(Shader.textureMapProgram, 'image'), 0);

                // Size of our canvas
                var width = 800;
                var height = 500;

                // Create camera perspective matrix

                Projection.makeIdentity();
                Projection.perspective(45, width / height, 0.05, 1000);

                gl.uniformMatrix4fv(gl.getUniformLocation(Shader.textureMapProgram, "Projection"), false, Projection.getAsFloat32Array());

                // Generate model-view matrix
                var x=0
                var y=0;
                var z=-5;

                var scale = 1.0;
                ModelView.makeIdentity();
                ModelView.scale(scale, scale, scale);
                ModelView.rotate(model_angle, 1, 1, 1);
                ModelView.rotate(model_angle, 0, 1, 0);
                ModelView.translate(x, y, z);
                gl.uniformMatrix4fv(gl.getUniformLocation(Shader.textureMapProgram, "ModelView"), false, ModelView.getAsFloat32Array());

                // Draw triangle
                gl.drawElements(gl.TRIANGLES, indices.length, gl.UNSIGNED_SHORT, 0);
            });
        }
    </script>
</head>
<style>
    #fx { position: relative; margin: 0 auto; width: 1000px; height: 500px; border: 1px solid gray; }
    #gl { width: 800px; height: 600px; }
</style>
<body style = "background: #202020; padding: 32px;">
<canvas id = "gl" width = "800" height = "600"></canvas>
</body>
</html>