From f5c3c1425727bae9403856f613acd8c8f4d7e49e Mon Sep 17 00:00:00 2001
From: James Ketrenos <james_gitlab@ketrenos.com>
Date: Fri, 10 Jan 2020 19:45:47 -0800
Subject: [PATCH] Reducing eps if count > 5*minPts

Signed-off-by: James Ketrenos <james_gitlab@ketrenos.com>
---
 scanner/scanner.c | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/scanner/scanner.c b/scanner/scanner.c
index 062de1f..d301a57 100644
--- a/scanner/scanner.c
+++ b/scanner/scanner.c
@@ -42,6 +42,7 @@ typedef struct Face {
 
 typedef struct FaceLink {
   struct FaceLink *pNext;
+  long double distance;
   Face *pFace;
 } FaceLink;
 
@@ -145,6 +146,7 @@ FaceLink *RangeQuery(Face **ppFaces, long int faceCount, Face *pQ, double eps) {
     if (pQ->distances[i] > 0.0 && pQ->distances[i] <= eps) {
       FaceLink *pLink = malloc(sizeof(*pLink));
       memset(pLink, 0, sizeof(*pLink));
+      pLink->distance = pQ->distances[i];
       pLink->pFace = pFace;
       pLink->pNext = pNeighbors;
       pNeighbors = pLink;
@@ -170,8 +172,6 @@ long int chainLength(FaceLink *pLink) {
   return count;
 }
 
-long int maxPts = 0;
-
 long int DBSCAN(Face **ppFaces, long int faceCount, double eps, int minPts) {
   long int C = 0;
   for (long int i = 0; i < faceCount; i++) {
@@ -184,18 +184,22 @@ long int DBSCAN(Face **ppFaces, long int faceCount, double eps, int minPts) {
       continue;
     }
 
+    double threshold = eps;
     FaceLink *pNeighbors = RangeQuery(ppFaces, faceCount, pFace, eps);
     long neighborCount = chainLength(pNeighbors);
-    if (neighborCount > maxPts) {
-      maxPts = neighborCount;
-      fprintf(stderr, "New max with id %ld: %ld\n", pFace->faceId, maxPts);
+    while (neighborCount > minPts * 5) {
+      fprintf(stderr, "\nWith eps of %f, %ld has %ld neighbors.", threshold, pFace->faceId, neighborCount);
+      threshold *= 0.9;
+      freeChain(pNeighbors);
+      pNeighbors = RangeQuery(ppFaces, faceCount, pFace, threshold);
+      neighborCount = chainLength(pNeighbors);
     }
+
     if (neighborCount < minPts) {
       pFace->clusterType = NOISE;
       freeChain(pNeighbors);
-      continue;
+      break;
     }
-    
     //printf("%ld has %ld neighbors.\n", pFace->faceId, neighborCount);
 
     C++;
@@ -224,11 +228,15 @@ long int DBSCAN(Face **ppFaces, long int faceCount, double eps, int minPts) {
 
       FaceLink *pSubNeighbors = RangeQuery(ppFaces, faceCount, pQ, eps);
       neighborCount = chainLength(pSubNeighbors);
+      while (neighborCount > minPts * 5) {
+        fprintf(stderr, "\nWith eps of %f, %ld has %ld neighbors.", threshold, pFace->faceId, neighborCount);
+        threshold *= 0.9;
+        freeChain(pNeighbors);
+        pNeighbors = RangeQuery(ppFaces, faceCount, pFace, threshold);
+        neighborCount = chainLength(pNeighbors);
+      }
+
       if (neighborCount >= minPts) {
-        if (neighborCount > maxPts) {
-          maxPts = neighborCount;
-          fprintf(stderr, "New max with id %ld: %ld\n", pFace->faceId, maxPts);
-        }
         pQ->clusterType = CORE;
         /* Append these neighbors to the end of the chain */
         FaceLink *pTmp = pLink;
@@ -376,7 +384,7 @@ int main(int argc, char *argv[]) {
       }
 
       if (profileDistance <= 0.5) {
-        fprintf(stderr, "Face id %ld distance from profile face: %Lf\n",
+        fprintf(stderr, "\nFace id %ld distance from profile face: %Lf",
           ppFaces[processed]->faceId, profileDistance);
         /* This entry will be skipped */
         entries--;