twgl.js/examples/text.html
2017-10-25 22:28:10 +09:00

211 lines
6.1 KiB
HTML

<!DOCTYPE html>
<html>
<head>
<meta charset="utf8">
<!--
@license twgl.js Copyright (c) 2015, Gregg Tavares All Rights Reserved.
Available via the MIT license.
see: http://github.com/greggman/twgl.js for details
-->
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<meta property="og:title" content="TWGL.js - text" />
<meta property="og:type" content="website" />
<meta property="og:image" content="http://twgljs.org/examples/screenshots/text.png" />
<meta property="og:description" content="TWGL.js - text" />
<meta property="og:url" content="http://twgljs.org" />
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:site" content="@greggman">
<meta name="twitter:creator" content="@greggman">
<meta name="twitter:domain" content="twgljs.org">
<meta name="twitter:title" content="TWGL.js - text">
<meta name="twitter:url" content="http://twgljs.org/examples/text.html">
<meta name="twitter:description" content="TWGL.js - text">
<meta name="twitter:image:src" content="http://twgljs.org/examples/screenshots/text.png">
<link href="/resources/images/twgljs-icon.png" rel="shortcut icon" type="image/png">
<title>twgl.js - text</title>
<style>
body {
margin: 0;
font-family: monospace;
}
canvas {
display: block;
width: 100vw;
height: 100vh;
}
#b {
position: absolute;
top: 10px;
width: 100%;
text-align: center;
z-index: 2;
}
</style>
</head>
<body>
<canvas id="c"></canvas>
<div id="b"><a href="http://twgljs.org">twgl.js</a> - text</div>
</body>
<script id="vs" type="notjs">
uniform mat4 u_worldViewProjection;
attribute vec4 a_position;
attribute vec2 a_texcoord;
varying vec2 v_texcoord;
void main() {
v_texcoord = a_texcoord;
gl_Position = u_worldViewProjection * a_position;
}
</script>
<script id="fs" type="notjs">
precision mediump float;
varying vec2 v_texcoord;
uniform sampler2D u_texture;
uniform vec4 u_color;
void main() {
vec4 color = texture2D(u_texture, v_texcoord) * u_color;
if (color.a < 0.1) {
discard;
}
gl_FragColor = color;
}
</script>
<script src="../dist/4.x/twgl-full.min.js"></script>
<script src="../3rdparty/chroma.min.js"></script>
<script>
"use strict";
twgl.setDefaults({attribPrefix: "a_"});
const m4 = twgl.m4;
const gl = document.querySelector("#c").getContext("webgl");
const programInfo = twgl.createProgramInfo(gl, ["vs", "fs"]);
const bufferInfo = twgl.primitives.createPlaneBufferInfo(gl, 1, 1, 1, 1, m4.rotationX(Math.PI * 0.5));
function rand(min, max) {
return min + Math.random() * (max - min);
}
// Shared values
const camera = m4.identity();
const view = m4.identity();
const viewProjection = m4.identity();
const world = m4.identity();
const ctx = document.createElement("canvas").getContext("2d");
function makeText(text) {
ctx.font = "20px monospace";
const t = ctx.measureText(text);
ctx.canvas.width = Math.ceil(t.width) + 2;
ctx.canvas.height = 24;
ctx.font = "20px monospace";
ctx.fillStyle = "white";
ctx.textAlign = "center";
ctx.textBaseAlign = "middle";
ctx.fillText(text, ctx.canvas.width / 2 | 0, ctx.canvas.height / 2 | 0);
return ctx.canvas;
}
const msgs = [
"al",
"joe",
"jill",
"brian",
"thomas",
"chrissy",
"jennifer",
"alexander",
];
gl.pixelStorei(gl.UNPACK_PREMULTIPLY_ALPHA_WEBGL, true);
const textTextures = msgs.map(function(msg) {
const canvas = makeText(msg);
const scale = 0.01;
return {
tex: twgl.createTexture(gl, { src: canvas }),
scale: [canvas.width * scale, canvas.height * scale, 1],
};
});
const objects = [];
const drawObjects = [];
const numObjects = 500;
const baseHue = rand(0, 360);
for (let ii = 0; ii < numObjects; ++ii) {
const texNdx = rand(0, textTextures.length) | 0;
const text = textTextures[texNdx];
const uniforms = {
u_texture: text.tex,
u_worldViewProjection: m4.identity(),
u_color: chroma.hsv((baseHue + rand(0, 60)) % 360, 1, 1).gl(),
};
drawObjects.push({
programInfo: programInfo,
bufferInfo: bufferInfo,
uniforms: uniforms,
});
objects.push({
translation: [rand(-10, 10), rand(-10, 10), rand(-10, 10)],
ySpeed: rand(0.1, 0.3),
zSpeed: rand(0.1, 0.3),
uniforms: uniforms,
texInfo: text,
});
}
const clearColor = chroma.hsv((baseHue + 30) % 360, 0.5, 0.5).gl();
function render(time) {
time *= 0.001;
twgl.resizeCanvasToDisplaySize(gl.canvas);
gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
gl.enable(gl.DEPTH_TEST);
gl.enable(gl.BLEND);
gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
gl.clearColor(clearColor[0], clearColor[1], clearColor[2], clearColor[3]);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
const projection = m4.perspective(30 * Math.PI / 180, gl.canvas.clientWidth / gl.canvas.clientHeight, 0.5, 100);
const eye = [1, 4, -20];
const target = [0, 0, 0];
const up = [0, 1, 0];
m4.lookAt(eye, target, up, camera);
m4.inverse(camera, view);
m4.multiply(projection, view, viewProjection);
objects.forEach(function(obj) {
const uni = obj.uniforms;
const texInfo = obj.texInfo;
m4.identity(world);
m4.rotateY(world, time * obj.ySpeed, world);
m4.rotateZ(world, time * obj.zSpeed, world);
m4.translate(world, obj.translation, world);
m4.rotateX(world, time, world);
m4.scale(world, texInfo.scale, world);
m4.multiply(view, world, world);
m4.multiply(projection, world, uni.u_worldViewProjection);
});
twgl.drawObjectList(gl, drawObjects);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
</script>
</html>