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|
<!doctype html>
<!--
Copyright 2018 The Immersive Web Community Group
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-->
<html>
<head>
<meta charset='utf-8'>
<meta name='viewport' content='width=device-width, initial-scale=1, user-scalable=no'>
<meta name='mobile-web-app-capable' content='yes'>
<meta name='apple-mobile-web-app-capable' content='yes'>
<meta http-equiv="origin-trial" content="As0BE09FBB6viNVrwWICektFyN2QlX8TMaTNjvpcGH4Jf7cmI3J4UYvtZQZvScykvRwtGkO4cacWZ3EvIiRUbgUAAABaeyJvcmlnaW4iOiJodHRwczovL3N0b3JhZ2UuZ29vZ2xlYXBpcy5jb206NDQzIiwiZmVhdHVyZSI6IldlYlhSRGVwdGgiLCJleHBpcnkiOjE2MTE3NzIwMTl9">
<title>AR Depth API</title>
<link href='../css/common.css' rel='stylesheet'></link>
<!--The polyfill is not needed for browser that have native API support,
but is linked by these samples for wider compatibility.-->
<!--script src='https://cdn.jsdelivr.net/npm/webxr-polyfill@latest/build/webxr-polyfill.js'></script-->
<script src='../js/xrray-polyfill.js' type='module'></script>
<script src='../js/webxr-polyfill.js'></script>
<script src='../js/webxr-button.js'></script>
<style>
#text-info {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
font-size: large;
color: red;
}
</style>
</head>
<body>
<header>
<details open>
<summary>AR Depth API - GPU access</summary>
<p>
This sample demonstrates use of a depth API in immersive-ar session.
The data will be uploaded to the GPU & accessed from a shader.
<a class="back" href="./index.html">Back</a>
<br/>
<hr/>
<input id="useFrontFacing" type="checkbox">
<label for="useFrontFacing">Enable front-facing camera</label>
<br/>
<input id="requestRawDepth" type="checkbox">
<label for="requestRawDepth">Request raw depth buffer</label>
<br/>
<input id="requestSmoothDepth" type="checkbox">
<label for="requestSmoothDepth">Request smooth depth buffer (will be requested after raw if both are requested)</label>
<br/>
<input id="matchDepthView" type="checkbox" checked>
<label for="matchDepthView">Align Depth and XRViews</label>
<br/>
</p>
</details>
</header>
<div id="text-overlay">
<br/>
<br/>
<div id="text-info"></div>
</div>
<script id="vertexShader" type="x-shader/x-vertex">
precision mediump float;
attribute vec2 aVertexPosition;
attribute vec2 aTexCoord;
varying vec2 vTexCoord;
void main(void) {
gl_Position = vec4(aVertexPosition, 0.0, 1.0);
vTexCoord = aTexCoord;
}
</script>
<script id="fragmentShader" type="x-shader/x-fragment" src="../shaders/depth-api-gpu.frag"></script>
<script id="turboFragment" type="x-shader/x-fragment" src="../shaders/turbo.glsl"></script>
<script type="module">
import {mat4, vec3, mat3, vec2} from '../js/cottontail/src/math/gl-matrix.js';
const useFrontFacing = document.getElementById('useFrontFacing');
const requestRawDepth = document.getElementById('requestRawDepth');
const requestSmoothDepth = document.getElementById('requestSmoothDepth');
// XR globals.
let xrButton = null;
let xrRefSpace = null;
let toggleDepthButton = null;
let requestToggleDepthActive = false;
// WebGL scene globals.
let gl = null;
let shaderProgram = null;
let programInfo = null;
let vertexBuffer = null;
let depthTexture = null;
// shader code
let vertexShaderSource = null;
let fragmentShaderSource = null;
const textOverlayElement = document.querySelector("#text-overlay");
if(!textOverlayElement) {
console.error("#text-overlay element not found!");
throw new Error("#text-overlay element not found!");
}
const textInfoElement = document.querySelector("#text-info");
if(!textInfoElement) {
console.error("#text-info element not found!");
throw new Error("#text-info element not found!");
}
function initXR() {
xrButton = new XRDeviceButton({
onRequestSession: onRequestSession,
onEndSession: onEndSession,
textEnterXRTitle: "START AR",
textXRNotFoundTitle: "AR NOT FOUND",
textExitXRTitle: "EXIT AR",
supportedSessionTypes: ['immersive-ar']
});
document.querySelector('header').appendChild(xrButton.domElement);
toggleDepthButton = new XRDeviceButton({
onRequestSession: ()=>{}, // Invoked when we have no session, no-op.
onEndSession: (session)=>{
requestToggleDepthActive = true;
},
textEnterXRTitle: "No Active Session",
textXRNotFoundTitle: "AR NOT FOUND",
textExitXRTitle: "Tap to toggle depth active",
supportedSessionTypes: ['immersive-ar']
});
document.querySelector('#text-overlay').appendChild(toggleDepthButton.domElement);
}
function onRequestSession() {
// Requests an immersive session with environment integration.
let options = {
requiredFeatures: ['depth-sensing'],
optionalFeatures: ['dom-overlay'],
domOverlay: { root: textOverlayElement },
depthSensing: {
usagePreference: ["cpu-optimized"],
dataFormatPreference: ["luminance-alpha"],
}
};
if (useFrontFacing.checked) {
options.optionalFeatures.push('front-facing');
}
options.depthSensing.matchDepthView = matchDepthView.checked;
if (requestRawDepth.checked || requestSmoothDepth.checked) {
options.depthSensing.depthTypeRequest = [];
if (requestRawDepth.checked) {
options.depthSensing.depthTypeRequest.push("raw");
}
if (requestSmoothDepth.checked) {
options.depthSensing.depthTypeRequest.push("smooth");
}
}
navigator.xr.requestSession('immersive-ar', options).then((session) => {
session.mode = 'immersive-ar';
xrButton.setSession(session);
fetchShaders().then(() => {
onSessionStarted(session);
});
});
}
function onSessionStarted(session) {
toggleDepthButton.setSession(session);
useFrontFacing.disabled = true;
session.addEventListener('end', onSessionEnded);
session.addEventListener('selectstart', onSelectStart);
let canvas = document.createElement('canvas');
gl = canvas.getContext('webgl', {
xrCompatible: true
});
initializeGL();
session.updateRenderState({ baseLayer: new XRWebGLLayer(session, gl) });
session.requestReferenceSpace('local').then((refSpace) => {
xrRefSpace = refSpace;
session.requestAnimationFrame(onXRFrame);
});
if(session.depthUsage != "cpu-optimized") {
throw new Error("Unsupported depth API usage!");
}
if(session.depthDataFormat != "luminance-alpha") {
throw new Error("Unsupported depth data format!");
}
}
function onEndSession(session) {
session.end();
}
function onSessionEnded(event) {
useFrontFacing.disabled = false;
xrButton.setSession(null);
toggleDepthButton.setSession(null);
}
function onSelectStart(event) {
requestToggleDepthActive = true;
}
// Helper, fetches shader source code based on the passed in ID of the <script> element.
// Will inspect src attribute value and issue fetch API call to obtain the script body.
async function fetchShader(id) {
const element = document.getElementById(id);
const url = element.src;
const response = await fetch(url);
const text = await response.text();
return text;
}
async function fetchShaders() {
vertexShaderSource = document.getElementById('vertexShader').textContent;
fragmentShaderSource = await fetchShader("fragmentShader") + "\n"
+ await fetchShader("turboFragment");
}
// Creates new GL buffer and uploads contents of |vertices| to it:
function uploadVertexData(vertices) {
const result = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, result);
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertices), gl.STATIC_DRAW);
gl.bindBuffer(gl.ARRAY_BUFFER, null);
return result;
}
function initializeGL() {
shaderProgram = initShaderProgram(vertexShaderSource, fragmentShaderSource);
programInfo = {
program: shaderProgram,
attribLocations: {
vertexPosition: gl.getAttribLocation(shaderProgram, 'aVertexPosition'),
texCoord: gl.getAttribLocation(shaderProgram, 'aTexCoord'),
},
uniformLocations: {
depthTexture: gl.getUniformLocation(shaderProgram, 'uDepthTexture'),
uvTransform: gl.getUniformLocation(shaderProgram, 'uUvTransform'),
rawValueToMeters: gl.getUniformLocation(shaderProgram, 'uRawValueToMeters'),
alpha: gl.getUniformLocation(shaderProgram, 'uAlpha'),
},
};
// clip space coordinates + texture space coordinates
// our depth buffer has an origin in top-left corner of the screen -
// we need to adjust the texture coordinates to account for that
const vertices_data = [
-1, -1, 0, 1, // bottom left
1, -1, 1, 1, // bottom right
-1, 1, 0, 0, // top left
1, 1, 1, 0, // top right
];
vertexBuffer = uploadVertexData(vertices_data);
depthTexture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, depthTexture);
// depth texture will likely not be power-of-2-sized, set parameters
// that would still make it work, see
// https://www.khronos.org/webgl/wiki/WebGL_and_OpenGL_Differences#Non-Power_of_Two_Texture_Support
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.bindTexture(gl.TEXTURE_2D, null);
}
function initShaderProgram(vsSource, fsSource) {
const vertexShader = loadShader(gl.VERTEX_SHADER, vsSource);
const fragmentShader = loadShader(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;
}
function loadShader(type, source) {
const shader = gl.createShader(type);
gl.shaderSource(shader, source);
gl.compileShader(shader);
if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
alert(
"An error occurred compiling the shaders: " +
gl.getShaderInfoLog(shader)
);
gl.deleteShader(shader);
return null;
}
return shader;
}
// Called every time a XRSession requests that a new frame be drawn.
function onXRFrame(t, frame) {
const session = frame.session;
session.requestAnimationFrame(onXRFrame);
if (requestToggleDepthActive) {
session.depthActive ? session.pauseDepthSensing() : session.resumeDepthSensing();
requestToggleDepthActive = false;
}
const baseLayer = session.renderState.baseLayer;
const pose = frame.getViewerPose(xrRefSpace);
if (pose) {
gl.bindFramebuffer(gl.FRAMEBUFFER, session.renderState.baseLayer.framebuffer);
// Clear the framebuffer
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
for (const view of pose.views) {
const viewport = baseLayer.getViewport(view);
gl.viewport(viewport.x, viewport.y,
viewport.width, viewport.height);
const depthData = frame.getDepthInformation(view);
if (depthData) {
textInfoElement.innerHTML = "";
renderDepthInformationGPU(depthData, view, viewport);
} else {
console.error("Depth data unavailable in the current frame!");
textInfoElement.innerHTML = "Depth data unavailable in the current frame!";
}
}
} else {
console.error("Pose unavailable in the current frame!");
textInfoElement.innerHTML = "Pose unavailable in the current frame!";
}
}
function renderDepthInformationGPU(depthData, view, viewport) {
const depth_width = depthData.width;
const depth_height = depthData.height;
gl.useProgram(programInfo.program);
gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer);
gl.vertexAttribPointer(
programInfo.attribLocations.vertexPosition,
2, // 2 components
gl.FLOAT,
false, // don't normalize
16, // stride = 4 floats * 4 bytes
0 // start at offset 0 of the buffer
);
gl.enableVertexAttribArray(
programInfo.attribLocations.vertexPosition
);
gl.vertexAttribPointer(
programInfo.attribLocations.texCoord,
2, // 2 components
gl.FLOAT,
false, // don't normalize
16, // stride = 4 floats * 4 bytes
8 // start at offset of 2 floats * 4 bytes of the buffer
);
gl.enableVertexAttribArray(
programInfo.attribLocations.texCoord
);
gl.bindTexture(gl.TEXTURE_2D, depthTexture);
// Supply the data buffer after converting it to Uint8Array - the
// gl.texImage2D expects Uint8Array when using gl.UNSIGNED_BYTE type.
gl.texImage2D(gl.TEXTURE_2D, 0, gl.LUMINANCE_ALPHA, depthData.width,
depthData.height, 0, gl.LUMINANCE_ALPHA, gl.UNSIGNED_BYTE,
new Uint8Array(depthData.data));
gl.activeTexture(gl.TEXTURE0);
gl.uniform1i(programInfo.uniformLocations.depthTexture, 0);
gl.uniformMatrix4fv(programInfo.uniformLocations.uvTransform, false,
depthData.normDepthBufferFromNormView.matrix);
gl.uniform1f(programInfo.uniformLocations.rawValueToMeters,
depthData.rawValueToMeters);
gl.uniform1f(programInfo.uniformLocations.alpha,
0.75);
gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
}
// Start the XR application.
initXR();
</script>
</body>
</html>
|
