Created
February 11, 2017 01:43
-
-
Save anonymous/0e8ec441c797a03e5265c9fd1f53d1c6 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import Exponent, { GLView } from 'exponent'; | |
import React from 'react'; | |
import { | |
StyleSheet, | |
Text, | |
View, | |
} from 'react-native'; | |
const vertSrc = ` | |
attribute vec2 position; | |
varying vec2 uv; | |
void main() { | |
gl_Position = vec4(position.x, -position.y, 0.0, 1.0); | |
uv = vec2(0.5, 0.5) * (position+vec2(1.0, 1.0)); | |
}`; | |
const fragSrc = ` | |
precision highp float; | |
varying vec2 uv; | |
void main () { | |
gl_FragColor = vec4(uv.x, uv.y, 0.5, 1.0); | |
}`; | |
export default class BasicScene extends React.Component { | |
static meta = { | |
description: 'Basic Scene', | |
}; | |
render() { | |
return ( | |
<GLView | |
style={this.props.style} | |
onContextCreate={this._onContextCreate} | |
/> | |
); | |
} | |
_onContextCreate = (gl) => { | |
// Compile vertex and fragment shader | |
const vert = gl.createShader(gl.VERTEX_SHADER); | |
gl.shaderSource(vert, vertSrc); | |
gl.compileShader(vert); | |
const frag = gl.createShader(gl.FRAGMENT_SHADER); | |
gl.shaderSource(frag, fragSrc); | |
gl.compileShader(frag); | |
// Link together into a program | |
const program = gl.createProgram(); | |
gl.attachShader(program, vert); | |
gl.attachShader(program, frag); | |
gl.linkProgram(program); | |
// Save position attribute | |
const positionAttrib = gl.getAttribLocation(program, 'position'); | |
// Create buffer | |
const buffer = gl.createBuffer(); | |
// Animate! | |
let skip = false; | |
const animate = () => { | |
try { | |
if (skip) { | |
// return; | |
} | |
// Clear | |
gl.clearColor(0, 0, 1, 1); | |
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT); | |
// Bind buffer, program and position attribute for use | |
gl.bindBuffer(gl.ARRAY_BUFFER, buffer); | |
gl.useProgram(program); | |
gl.enableVertexAttribArray(positionAttrib); | |
gl.vertexAttribPointer(positionAttrib, 2, gl.FLOAT, false, 0, 0); | |
// Buffer data and draw! | |
const speed = this.props.speed || 1; | |
const a = 0.48 * Math.sin(0.001 * speed * Date.now()) + 0.5; | |
const verts = new Float32Array([ | |
-a, -a, a, -a, -a, a, | |
-a, a, a, -a, a, a, | |
]); | |
gl.bufferData(gl.ARRAY_BUFFER, verts, gl.STATIC_DRAW); | |
gl.drawArrays(gl.TRIANGLES, 0, verts.length / 2); | |
// Submit frame | |
gl.flush(); | |
gl.endFrameEXP(); | |
} finally { | |
skip = !skip; | |
gl.enableLogging = false; | |
requestAnimationFrame(animate); | |
} | |
}; | |
animate(); | |
} | |
} | |
class App extends React.Component { | |
render() { | |
return ( | |
<View style={styles.container}> | |
<BasicScene style={{ width: 400, height: 400 }} /> | |
</View> | |
); | |
} | |
} | |
const styles = StyleSheet.create({ | |
container: { | |
flex: 1, | |
backgroundColor: '#fff', | |
alignItems: 'center', | |
justifyContent: 'center', | |
}, | |
}); | |
Exponent.registerRootComponent(App); |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment