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'use strict';
// This file introduces constants used to mock depth data for depth sensing API.
const convertDepthBufferToArrayBuffer = function (data, desiredFormat) {
if(desiredFormat == "luminance-alpha") {
const result = new ArrayBuffer(data.length * 2); // each entry has 2 bytes
const view = new Uint16Array(result);
for(let i = 0; i < data.length; ++i) {
view[i] = data[i];
}
return new Uint8Array(result);
} else if(desiredFormat == "float32") {
const result = new ArrayBuffer(data.length * 4); // each entry has 4 bytes
const view = new Float32Array(result);
for(let i = 0; i < data.length; ++i) {
view[i] = data[i];
}
return new Uint8Array(result);
} else {
throw new Error("Unrecognized data format!");
}
}
// Let's assume that the depth values are in cm, Xcm = x * 1/100m
const RAW_VALUE_TO_METERS = 1/100;
const createDepthSensingData = function() {
const depthSensingBufferHeight = 5;
const depthSensingBufferWidth = 7;
const depthSensingBuffer = [
1, 1, 1, 1, 1, 1, 1, // first row
1, 2, 3, 4, 5, 6, 7,
1, 4, 9, 16, 25, 36, 49,
1, 8, 27, 64, 125, 216, 343,
1, 16, 81, 256, 625, 1296, 2401,
]; // depthSensingBuffer value at column c, row r is Math.pow(c+1, r).
// Let's assume that the origin of the depth buffer is in the bottom right
// corner, with X's growing to the left and Y's growing upwards.
// This corresponds to the origin at 2401 in the above matrix, with X axis
// growing from 2401 towards 1296, and Y axis growing from 2401 towards 343.
// This corresponds to a rotation around Z axis by 180 degrees, with origin at [1,1].
const depthSensingBufferFromViewerTransform = {
position: [1, 1, 0],
orientation: [0, 0, 1, 0],
};
return {
depthData: convertDepthBufferToArrayBuffer(depthSensingBuffer, "luminance-alpha"),
width: depthSensingBufferWidth,
height: depthSensingBufferHeight,
normDepthBufferFromNormView: depthSensingBufferFromViewerTransform,
rawValueToMeters: RAW_VALUE_TO_METERS,
};
};
const DEPTH_SENSING_DATA = createDepthSensingData();
// Returns expected depth value at |column|, |row| coordinates, expressed
// in depth buffer's coordinate system.
const getExpectedValueAt = function(column, row) {
return Math.pow(column+1, row) * RAW_VALUE_TO_METERS;
};
const VALID_DEPTH_CONFIG_CPU_USAGE = {
usagePreference: ['cpu-optimized'],
dataFormatPreference: ['luminance-alpha', 'float32'],
};
const VALID_DEPTH_CONFIG_GPU_USAGE = {
usagePreference: ['gpu-optimized'],
dataFormatPreference: ['luminance-alpha', 'float32'],
};