Change velocity-difference threshold calculation method and misc small non-functional changes (reverted from commit bb18055c66)

This commit is contained in:
Pitchaya Boonsarngsuk
2018-01-24 08:51:09 +00:00
parent bb18055c66
commit df652ffec6

View File

@@ -1,98 +1,287 @@
import {pointOnCircle, takeSampleFrom} from "./helpers";
import {placeNearToNearestNeighbour} from "./interpCommon";
export default function(sampleSet, remainderSet, interpSubset, nPivots, distanceFunction) {
var distance = distanceFunction;
export default function(sampleSet, remainderSet, numPivots, distanceFn) {
// Pivot based parent finding
let numBuckets = Math.floor(Math.sqrt(sampleSet.length));
let pivots = takeSampleFrom(sampleSet, numPivots);
console.log("Pivots", pivots);
// Common temporary variables
let i, j, pivot, sample, bucketWidth; // Temp var, declared seperately to avoid GC
let pivotsBuckets = []; // [ For each Pivot:[For each bucket:[each point in bucket]] ]
var numBuckets = Math.floor(Math.sqrt(sampleSet.length)),
numPivots = nPivots,
parents = [],
maxDists = [],
bucketWidths = [],
pivotsBuckets = [];
for (i = 0; i < numPivots; i++) {
console.log("Parents, pivots=", numPivots);
var pivots = createRandomSample(sampleSet.concat(remainderSet), sampleSet.length, numPivots);
for (var i = 0; i < numPivots; i++) {
pivotsBuckets[i] = [];
for (j = 0; j < numBuckets; j++) {
for (var j = 0; j < numBuckets; j++) {
pivotsBuckets[i][j] = [];
}
}
// Pre-calculate distance between each sample to each pivot
let distCache = [], // [ For each Sample:[For each Pivot: distance] ]
bucketWidths = []; // [ For each Pivot: width of each bucket ]
// Pre-processing
var fullDists = []
for (var i = 0; i < sampleSet.length; i++) {
fullDists[i] = [];
}
for (i = 0; i < sampleSet.length; i++)
distCache[i] = [];
for (j = 0; j < numPivots; j++) {
pivot = pivots[j],
maxDist = -1;
for (i = 0; i < sampleSet.length; i++) {
sample = sampleSet[i];
if (pivot !== sample) {
distCache[i][j] = distanceFn(pivot, sample);
if (distCache[i][j] > maxDist)
maxDist = distCache[i][j];
for (var j = 0, maxDist = -1; j < numPivots; j++) {
var c1 = pivots[j];
for (var i = 0; i < sampleSet.length; i++) {
var c2 = sampleSet[i];
if (c1 !== c2) {
var dist = distance(c1, c2, props, norm);
// console.log(dist, c1, c2);
if (dist > maxDist) {
maxDist = dist;
}
fullDists[i][j] = dist;
} else {
distCache[i][j] = 0;
fullDists[i][j] = 0.0001;
}
}
maxDists.push(maxDist);
bucketWidths.push(maxDist / numBuckets);
}
// console.log(distCaches);
// console.log(fullDists);
// Put samples (pivot included) into buckets
for (j = 0; j < numPivots; j++) {
bucketWidth = bucketWidths[j];
for (i = 0; i < sampleSet.length; i++) {
sample = sampleSet[i];
pivotsBuckets[j][Math.floor(distCache[i][j] / bucketWidth)].push(sample);
for (var j = 0; j < numPivots; j++) {
var bucketWidth = bucketWidths[j];
for (var i = 0; i < sampleSet.length; i++) {
var tmp = pivotsBuckets[j][Math.floor((fullDists[i][j] - 0.0001) / bucketWidth)];
// pivotsBuckets[j][Math.floor((fullDists[i][j] - 0.0001) / bucketWidth)].push(sampleSet[i]);
// console.log(tmp, i, j, bucketWidth, Math.floor((fullDists[i][j] - 0.0001) / bucketWidth));
tmp.push(sampleSet[i]);
}
}
//Plot each of the remainder nodes
for (let node of remainderSet) {
let sampleSubsetDistanceCache = [],
sampleSubset = takeSampleFrom(sampleSet, Math.sqrt(sampleSet.length)).sample;
for (var i = 0; i < remainderSet.length; i++) {
var node = remainderSet[i],
minNode = sampleSet[0],
minDist = 0,
sampleCache = [];
// Pivot based parent search
for (let p = 0; p < numPivots; p++) {
let pivot = pivots[p];
let bucketWidth = bucketWidths[p];
let dist = distanceFn(node, pivot);
let index = sampleSubset.indexOf(pivot);
if (index !== -1)
sampleSubsetDistanceCache[index] = dist;
let bucketNumber = Math.floor(dist / bucketWidth);
if (bucketNumber >= numBuckets) {
bucketNumber = numBuckets - 1;
} else if (bucketNumber < 0) { // Should never be negative anyway
bucketNumber = 0;
}
let clDist, minNode;
for (let candidateNode of pivotsBuckets[p][bucketNumber]) {
dist = distanceFn(candidateNode, node);
if (candidateNode <= clDist) {
clDist = candidateNode;
minNode = bucketContents[w];
var node = remainderSet[i];
var clDist = Number.MAX_VALUE;
for (var p = 0; p < numPivots; p++) {
var comp = pivots[p];
var bucketWidth = bucketWidths[p];
if (node !== comp) {
var dist = distance(node, comp, props, norm);
var bNum = Math.floor((dist - 0.0001) / bucketWidth);
if (bNum >= numBuckets) {
bNum = numBuckets - 1;
} else if (bNum < 0) {
bNum = 0;
}
var bucketContents = pivotsBuckets[p][bNum];
for (var w = 0; w < bucketContents.length; w++) {
var c1 = bucketContents[w];
if (c1 != node) {
dist = distance(c1, node, props, norm);
if (dist <= clDist) {
clDist = dist;
minNode = bucketContents[w];
}
}
}
}
}
for (let k = 0; k < sampleSubset.length; k++) {
if (sampleSubsetDistanceCache[k] !== undefined)
sampleSubsetDistanceCache[k] = distanceFn(node, sampleSubset[k]);
for (var k = 0; k < interpSubset.length; k++) {
sampleCache[k] = distance(node, interpSubset[k], props, norm);
}
let radius = distanceFn(node, minNode);
placeNearToNearestNeighbour(node, minNode, radius, sampleSubset, sampleSubsetDistanceCache);
var radius = distance(node, minNode, props, norm);
placeNearToNearestNeighbour(node, minNode, interpSubset, sampleCache, radius);
}
}
function placeNearToNearestNeighbour(node, minNode, sample, sampleCache, radius) {
var
dist0 = 0.0,
dist90 = 0.0,
dist180 = 0.0,
dist270 = 0.0,
lowBound = 0.0,
highBound = 0.0;
dist0 = sumDistToSample(node, centerPoint(0, radius, minNode.x, minNode.y), sample, sampleCache);
dist90 = sumDistToSample(node, centerPoint(90, radius, minNode.x, minNode.y), sample, sampleCache);
dist180 = sumDistToSample(node, centerPoint(180, radius, minNode.x, minNode.y), sample, sampleCache);
dist270 = sumDistToSample(node, centerPoint(270, radius, minNode.x, minNode.y), sample, sampleCache);
// console.log(dist0, dist90, dist180, dist270);
// Determine the closest quadrant
if (dist0 == dist180) {
if (dist90 > dist270)
lowBound = highBound = 270;
else
lowBound = highBound = 90;
} else if (dist90 == dist270) {
if (dist0 > dist180)
lowBound = highBound = 180;
else
lowBound = highBound = 0;
} else if (dist0 > dist180) {
if (dist90 > dist270) {
lowBound = 180;
highBound = 270;
} else {
lowBound = 90;
highBound = 180;
}
} else {
if (dist90 > dist270) {
lowBound = 270;
highBound = 360;
} else {
lowBound = 0;
highBound = 90;
}
}
var angle = binarySearch(lowBound, highBound, minNode.x, minNode.y, radius, node, sample, sampleCache);
var newPoint = centerPoint(angle, radius, minNode.x, minNode.y);
// console.log(newPoint);
node.x = newPoint.x;
node.y = newPoint.y;
// for (var i = 0; i < 20; i++) {
// var forces = sumForcesToSample(node, sample, sampleCache);
// // console.log(forces);
// node.x += forces.x;
// node.y += forces.y;
// }
}
function centerPoint(angle, radius, posX, posY) {
var x = posX + Math.cos(toRadians(angle) * radius);
var y = posY + Math.sin(toRadians(angle) * radius);
return {
x: x,
y: y
};
}
function toRadians(degrees) {
return degrees * (Math.PI / 180);
}
function sumDistToSample(node, point, sample, sampleCache) {
var total = 0.0;
// console.log(total, sample);
for (var i = 0; i < sample.length; i++) {
var s = sample[i];
var realDist = Math.hypot(s.x - point.x, s.y - point.y);
var desDist = sampleCache[i];
total += Math.abs(realDist - desDist);
}
return total;
}
function sumForcesToSample(node, sample, sampleCache) {
var x = 0,
y = 0,
// len = 0,
dist = 0,
force,
SPRING_FORCE = 0.7;
for (var i = 0, unitX, unitY; i < sample.length; i++) {
var s = sample[i];
if (s !== node) {
unitX = s.x - node.x;
unitY = s.y - node.y;
// Normalize coordinates
len = Math.sqrt(unitX * unitX + unitY * unitY);
unitX /= len;
unitY /= len;
console.log(unitX, unitY);
var realDist = Math.sqrt(unitX * unitX + unitY * unitY);
var desDist = sampleCache[i];
dist += realDist - desDist;
force = (SPRING_FORCE * dist);
x += unitX * force;
y += unitY * force;
}
x *= (1.0 / sample.length);
y *= (1.0 / sample.length);
return {
x: x,
y: y
};
}
}
function createRandomSample(nodes, max, size) {
var randElements = [];
for (var i = 0; i < size; ++i) {
// Stop when no new elements can be found.
if (randElements.size >= nodes.length) {
break;
}
var rand = Math.floor((Math.random() * max));
// If the rand is already in random list or in exclude list
// ignore it and get a new value.
while (randElements.includes(rand)) {
rand = Math.floor((Math.random() * max));
}
randElements.push(nodes[rand]);
}
return randElements;
}
function binarySearch(lb, hb, x, y, r, node, sample, sampleCache) {
while (lb <= hb) {
var mid = Math.round((lb + hb) / 2);
if ((mid === lb) || (mid === hb)) {
if (sumDistToSample(node, centerPoint(lb, r, x, y), sample, sampleCache) >=
sumDistToSample(node, centerPoint(hb, r, x, y), sample, sampleCache)) {
return hb;
} else {
return lb;
}
} else {
var distMidLeft = sumDistToSample(node, centerPoint(mid + 1, r, x, y), sample, sampleCache);
var distMidRight = sumDistToSample(node, centerPoint(mid - 1, r, x, y), sample, sampleCache);
var distMid = sumDistToSample(node, centerPoint(mid, r, x, y), sample, sampleCache);
if (distMid > distMidLeft) {
lb = mid + 1;
} else if (distMid > distMidRight) {
hb = mid - 1;
} else {
return mid;
}
}
}
return -1;
}