Colored square

config/webpack.client.common.js

@@ -3,7 +3,7 @@ const nodeExternals = require('webpack-node-externals');
 const EsLint = require('eslint-webpack-plugin');
 
 module.exports = {
-	entry: path.resolve(__dirname, '../src/client/main.tsx'),
+	entry: path.resolve(__dirname, '../src/client/main.ts'),
 	output: {
 		filename: 'bundle.js',
 		path: path.resolve(__dirname, '../dist/client'),

package-lock.json

@@ -3194,6 +3194,11 @@
         "pump": "^3.0.0"
       }
     },
+    "gl-mat4": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/gl-mat4/-/gl-mat4-1.2.0.tgz",
+      "integrity": "sha512-sT5C0pwB1/e9G9AvAoLsoaJtbMGjfd/jfxo8jMCKqYYEnjZuFvqV5rehqar0538EmssjdDeiEWnKyBSTw7quoA=="
+    },
     "glob": {
       "version": "7.1.6",
       "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.6.tgz",

package.json

@@ -62,6 +62,7 @@
   "dependencies": {
     "ejs": "^3.1.5",
     "express": "^4.17.1",
+    "gl-mat4": "^1.2.0",
     "react": "^17.0.1",
     "react-dom": "^17.0.1"
   }

public/css/style.css

@@ -0,0 +1,18 @@
+html {
+	padding: 0;
+	margin: 0;
+	height: 100%;
+	width: 100%;
+}
+
+body {
+	padding: 0;
+	margin: 0;
+	height: 100%;
+	width: 100%;
+	overflow: hidden;
+}
+
+#glCanvas {
+	display: inline-block;
+}

src/client/components/Root.tsx

@@ -1,12 +0,0 @@
-import React from 'react';
-
-/**
- * @return {jsx} The root component
- */
-export default function Root() {
-	return (
-		<div id='root'>
-			Hello World from React !
-		</div>
-	);
-}

src/client/main.ts

@@ -0,0 +1,261 @@
+// @ts-ignore
+import mat4 from 'gl-mat4';
+
+main();
+
+/**
+ * The program purpose is encapsulated in a main function
+ */
+function main() {
+	const canvas: any = document.querySelector('#glCanvas')!;
+	const gl = canvas.getContext('webgl');
+
+	if (gl == null) {
+		canvas.parentNode.removeChild(canvas);
+		document.getElementById('root')!.insertAdjacentHTML('beforeend',
+			`<p>Unable to initialize WebGL. Your browser or machine may not
+			support it.</p>`);
+	}
+
+	const vsSource = `
+		attribute vec4 aVertexPosition;
+		attribute vec4 aVertexColor;
+
+		uniform mat4 uModelViewMatrix;
+		uniform mat4 uProjectionMatrix;
+
+		varying lowp vec4 vColor;
+
+		void main() {
+			gl_Position = uProjectionMatrix *
+				uModelViewMatrix *
+				aVertexPosition;
+			vColor = aVertexColor;
+		}
+	`;
+	const fsSource = `
+		varying lowp vec4 vColor;
+
+		void main() {
+			gl_FragColor = vColor;
+		}
+	`;
+
+
+	const shaderProgram = initShaderProgram(gl, vsSource, fsSource);
+
+	const programInfo: any = {
+		program: shaderProgram,
+		attribLocations: {
+			vertexPosition: gl.getAttribLocation(shaderProgram,
+				'aVertexPosition'),
+			vertexColor: gl.getAttribLocation(shaderProgram, 'aVertexColor'),
+		},
+		uniformLocations: {
+			projectionMatrix: gl.getUniformLocation(
+				shaderProgram, 'uProjectionMatrix'),
+			modelViewMatrix: gl.getUniformLocation(
+				shaderProgram, 'uModelViewMatrix'),
+		},
+	};
+
+	const buffers = initBuffers(gl);
+	drawScene(gl, programInfo, buffers);
+}
+
+/**
+ * Initialize a shader program, so WebGL knows how to draw our data
+ * @param {any} gl the WebGL context
+ * @param {string} vsSource the vertex shader source
+ * @param {string} fsSource the fragment shader source
+ * @return {any} the shader program
+ */
+function initShaderProgram(gl: any, vsSource: string, fsSource: string) {
+	const vertexShader = loadShader(gl, gl.VERTEX_SHADER, vsSource);
+	const fragmentShader = loadShader(gl, gl.FRAGMENT_SHADER, fsSource);
+
+	// Create the shader program
+	const shaderProgram = gl.createProgram();
+	gl.attachShader(shaderProgram, vertexShader);
+	gl.attachShader(shaderProgram, fragmentShader);
+	gl.linkProgram(shaderProgram);
+
+	// If creating the shader program failed, alert
+	if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
+		alert('Unable to initialize the shader program: ' +
+			gl.getProgramInfoLog(shaderProgram));
+		return null;
+	}
+	return shaderProgram;
+}
+
+/**
+ * load a GL shader
+ * @param {any} gl the WebGL context
+ * @param {any} type type of shader to load
+ * @param {string} source source code of shader
+ * @return {any} the loaded shader
+ */
+function loadShader(gl: any, type: any, source: string) {
+	const shader = gl.createShader(type);
+	// Send the source to the shader object
+	gl.shaderSource(shader, source);
+	// Compile the shader program
+	gl.compileShader(shader);
+	// See if it compiled successfully
+	if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
+		alert('An error occurred compiling the shaders: ' +
+			gl.getShaderInfoLog(shader));
+		gl.deleteShader(shader);
+		return null;
+	}
+	return shader;
+}
+
+/**
+ * init buffers to create a square
+ * @param {any} gl the web gl context
+ * @return {any} the buffer
+ */
+function initBuffers(gl: any) {
+	// Create a buffer for the square's positions.
+	const positionBuffer = gl.createBuffer();
+	// Select the positionBuffer as the one to apply buffer
+	// operations to from here out.
+	gl.bindBuffer(gl.ARRAY_BUFFER, positionBuffer);
+	// Now create an array of positions for the square.
+	const positions = [
+		-1.0, 1.0,
+		1.0, 1.0,
+		-1.0, -1.0,
+		1.0, -1.0,
+	];
+	// Now pass the list of positions into WebGL to build the
+	// shape. We do this by creating a Float32Array from the
+	// JavaScript array, then use it to fill the current buffer.
+	gl.bufferData(
+		gl.ARRAY_BUFFER,
+		new Float32Array(positions),
+		gl.STATIC_DRAW);
+
+	const colors = [
+		1.0, 1.0, 1.0, 1.0,
+		1.0, 0.0, 0.0, 1.0,
+		0.0, 1.0, 0.0, 1.0,
+		0.0, 0.0, 1.0, 1.0,
+	];
+
+	const colorBuffer = gl.createBuffer();
+	gl.bindBuffer(gl.ARRAY_BUFFER, colorBuffer);
+	gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(colors), gl.STATIC_DRAW);
+
+	return {
+		position: positionBuffer,
+		color: colorBuffer,
+	};
+}
+
+/**
+ * Draw a webgl scene
+ * @param {any} gl the WebGL context
+ * @param {any} programInfo WebGL program information
+ * @param {any} buffers the buffers to draw
+ */
+function drawScene(gl: any, programInfo: any, buffers: any) {
+	gl.clearColor(0.0, 0.0, 0.0, 1.0);
+	gl.clearDepth(1.0);
+	gl.enable(gl.DEPTH_TEST);
+	gl.depthFunc(gl.LEQUAL);
+	// Clear the canvas before we start drawing on it.
+	gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
+
+	// Create a perspective matrix, a special matrix that is
+	// used to simulate the distortion of perspective in a camera.
+	// Our field of view is 45 degrees, with a width/height
+	// ratio that matches the display size of the canvas
+	// and we only want to see objects between 0.1 units
+	// and 100 units away from the camera.
+	const fieldOfView = 45 * Math.PI / 180;
+	const aspect = gl.canvas.clientWidth / gl.canvas.clientHeight;
+	const zNear = 0.1;
+	const zFar = 100.0;
+	const projectionMatrix = mat4.create();
+
+	// note: glmatrix.js always has the first argument
+	// as the destination to receive the result.
+	mat4.perspective(
+		projectionMatrix,
+		fieldOfView,
+		aspect,
+		zNear,
+		zFar);
+
+	// Set the drawing position to the "identity" point, which is
+	// the center of the scene.
+	const modelViewMatrix = mat4.create();
+
+	// Now move the drawing position a bit to where we want to
+	// start drawing the square.
+	mat4.translate(
+		modelViewMatrix,
+		modelViewMatrix,
+		[-0.0, 0.0, -6.0]);
+
+	// Tell WebGL how to pull out the positions from the position
+	// buffer into the vertexPosition attribute.
+	{
+		const numComponents = 2;
+		const type = gl.FLOAT;
+		const normalize = false;
+		const stride = 0;
+		const offset = 0;
+		gl.bindBuffer(gl.ARRAY_BUFFER, buffers.position);
+		gl.vertexAttribPointer(
+			programInfo.attribLocations.vertexPosition,
+			numComponents,
+			type,
+			normalize,
+			stride,
+			offset);
+		gl.enableVertexAttribArray(
+			programInfo.attribLocations.vertexPosition);
+	}
+
+	// Tell WebGL how to pull out the positions from the position
+	// buffer into the vertexPosition attribute.
+	{
+		const numComponents = 4;
+		const type = gl.FLOAT;
+		const normalize = false;
+		const stride = 0;
+		const offset = 0;
+		gl.bindBuffer(gl.ARRAY_BUFFER, buffers.color);
+		gl.vertexAttribPointer(
+			programInfo.attribLocations.vertexColor,
+			numComponents,
+			type,
+			normalize,
+			stride,
+			offset);
+		gl.enableVertexAttribArray(
+			programInfo.attribLocations.vertexColor);
+	}
+
+	// Tell WebGL to use our program when drawing
+	gl.useProgram(programInfo.program);
+	// Set the shader uniforms
+	gl.uniformMatrix4fv(
+		programInfo.uniformLocations.projectionMatrix,
+		false,
+		projectionMatrix);
+	gl.uniformMatrix4fv(
+		programInfo.uniformLocations.modelViewMatrix,
+		false,
+		modelViewMatrix);
+
+	{
+		const offset = 0;
+		const vertexCount = 4;
+		gl.drawArrays(gl.TRIANGLE_STRIP, offset, vertexCount);
+	}
+}

src/client/main.tsx

@@ -1,13 +0,0 @@
-import React from 'react';
-import {hydrate, render} from 'react-dom';
-import Root from './components/Root';
-
-const root = document.getElementById('root');
-let renderMethod;
-if (root && root.innerHTML !== '') {
-	renderMethod = hydrate;
-} else {
-	renderMethod = render;
-}
-
-renderMethod(<Root />, document.getElementById('root'));

views/index.ejs

@@ -3,14 +3,17 @@
 	<head>
 		<meta charset="UTF-8">
 		<meta name="viewport" content="width=device-width, initial-scale=1">
-		<meta name="Description" content="Web version of digital art exhibition">
-		<title>Web-Expo</title>
+		<meta
+			name="Description"
+			content="Simple WebGL app to demonstrate my skills">
+		<title>WebGL</title>
 
-		<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
 		<link rel="stylesheet" href="static/css/style.css">
 	</head>
 	<body>
-		<div id="root"></div>
+		<div id="root">
+			<canvas id='glCanvas' width='640' height='480'></canvas>
+		</div>
 		<script src="js/bundle.js"></script>
 	</body>
 </html>