From de02a0d31234490c656f95d1f50bf4dd74c96464 Mon Sep 17 00:00:00 2001
From: mika <mika@mika-ideacentre-Y710-Cube-15ISH>
Date: Wed, 5 Dec 2018 05:57:12 +0100
Subject: [PATCH] improving circle
---
src/delaunay.c | 23 ++++++++++++++---------
src/main.c | 2 +-
src/voronoi.c | 3 ++-
3 files changed, 17 insertions(+), 11 deletions(-)
diff --git a/src/delaunay.c b/src/delaunay.c
index fcdcca8..812294e 100644
--- a/src/delaunay.c
+++ b/src/delaunay.c
@@ -89,6 +89,19 @@ double det2(double a, double b, double c, double d) {
return a*d-b*c;
}
+void circleCenter(const vertex* v1, const vertex* v2, const vertex* v3,
+ vertex* center) {
+ double ax = 2 * (v1->x - v2->x);
+ double bx = 2 * (v1->y - v2->y);
+ double cx = v1->x * v1->x - v2->x * v2->x + v1->y * v1->y - v2->y * v2->y;
+ double ay = 2 * (v1->x - v3->x);
+ double by = 2 * (v1->y - v3->y);
+ double cy = v1->x * v1->x - v3->x * v3->x + v1->y * v1->y - v3->y * v3->y;
+ double det = det2(ax, bx, ay, by);
+ center->x = det2(cx, bx, cy, by) / det;
+ center->y = det2(ax, cx, ay, cy) / det;
+}
+
/*
* https://stackoverflow.com/questions/22791951/algorithm-to-find-an-arc-its-center-radius-and-angles-given-3-points
* https://de.wikipedia.org/wiki/Cramersche_Regel
@@ -97,15 +110,7 @@ double det2(double a, double b, double c, double d) {
//TODO seperate radius from this function
circle circleFrom3Points(vertex v1, vertex v2, vertex v3) {
circle c;
- double ax = 2*(v1.x-v2.x);
- double bx = 2*(v1.y-v2.y);
- double cx = v1.x*v1.x - v2.x*v2.x + v1.y*v1.y - v2.y*v2.y;
- double ay = 2*(v1.x-v3.x);
- double by = 2*(v1.y-v3.y);
- double cy = v1.x*v1.x - v3.x*v3.x + v1.y*v1.y - v3.y*v3.y;
- double det = det2(ax, bx, ay, by);
- c.center.x = det2(cx, bx, cy, by)/det;
- c.center.y = det2(ax, cx, ay, cy)/det;
+ circleCenter(&v1, &v2, &v3, &c.center);
c.radius = sqrt((v1.x-c.center.x)*(v1.x-c.center.x)+(v1.y-c.center.y)*(v1.y-c.center.y));
return c;
}
diff --git a/src/main.c b/src/main.c
index 845c941..4964086 100644
--- a/src/main.c
+++ b/src/main.c
@@ -13,7 +13,7 @@ int main(int argc, char *argv[]) {
//input: 1. function 0=cws_delaunay 2. # of points, 3. # of executions
//create_image();
//write_ppm ( "sine.ppm" );
- int numberOfPoints = 2000;
+ int numberOfPoints = 10000;
int function = 0;
int executions = 1;
if(argc > 0) {
diff --git a/src/voronoi.c b/src/voronoi.c
index 250a769..15bafae 100644
--- a/src/voronoi.c
+++ b/src/voronoi.c
@@ -83,7 +83,8 @@ void voronoiCws(vertex* S, int size) {
int isTriangle;
clockwiseNextDelaunayEdge(&i, &j, &k, S, &size, &isTriangle);
if(isTriangle == 2) {
- currentV = vertexCircle2vertex((vertexCircle){S[i], S[j], S[k]});
+ //currentV = vertexCircle2vertex((vertexCircle){S[i], S[j], S[k]});
+ circleCenter(S[i], S[j], S[k], currentV);
if(first) {
first = 0;
firstV = currentV;
--
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