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update src

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This commit is contained in:
张壹
2021-09-15 15:49:28 +08:00
parent a958701820
commit bc6b04bb06
3 changed files with 99 additions and 48 deletions
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40
delaunay.h
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@@ -12,15 +12,13 @@
#include "cmath" #include "cmath"
#include "vector" #include "vector"
#include "iostream"
#define ZERO 1e-5 #define ZERO 1e-5
// Start vertex definition // Start vertex definition
struct vertex2dc struct vertex2dc
{ {
unsigned int id; unsigned int id; // index of the vertex
double x, y; double x, y; // position of the vertex
vertex2dc() : x(NAN), y(NAN), id(0) {} vertex2dc() : x(NAN), y(NAN), id(0) {}
vertex2dc(double inx, double iny, unsigned int inid = 0) {set(inx, iny, inid);} vertex2dc(double inx, double iny, unsigned int inid = 0) {set(inx, iny, inid);}
@@ -30,12 +28,21 @@ struct vertex2dc
return; return;
} }
}; };
bool operator ==(const vertex2dc &a, const vertex2dc &b) // overload the == operator for vertex2dc type
{
if(fabs(a.x - b.x) <= ZERO && fabs(a.y - b.y) <= ZERO)
{
return true;
}
return false;
}
// End vertex definition // End vertex definition
// Start edge definition // Start edge definition
struct edge struct edge
{ {
vertex2dc *vert[2]; vertex2dc *vert[2]; // vertex of the edge
edge() {vert[0] = vert[1] = nullptr;} edge() {vert[0] = vert[1] = nullptr;}
edge(vertex2dc *v0ptr, vertex2dc *v1ptr) {set(v0ptr, v1ptr);} edge(vertex2dc *v0ptr, vertex2dc *v1ptr) {set(v0ptr, v1ptr);}
@@ -46,7 +53,7 @@ struct edge
} }
}; };
bool operator ==(const edge &a, const edge &b) bool operator ==(const edge &a, const edge &b) // overload the == operator for edge type
{ {
if((a.vert[0] == b.vert[0] && a.vert[1] == b.vert[1]) || if((a.vert[0] == b.vert[0] && a.vert[1] == b.vert[1]) ||
(a.vert[0] == b.vert[1] && a.vert[1] == b.vert[0])) (a.vert[0] == b.vert[1] && a.vert[1] == b.vert[0]))
@@ -60,9 +67,9 @@ bool operator ==(const edge &a, const edge &b)
// Start triangle definition // Start triangle definition
struct triangle struct triangle
{ {
vertex2dc *vert[3]; vertex2dc *vert[3]; // vertex of the triangle
double cx, cy; // triangle's circular center double cx, cy; // center of the triangle's circumcircle
double cr; // triangle's circular radius double cr; // radius of the circumcircle
triangle() {vert[0] = vert[1] = vert[2] = nullptr;} triangle() {vert[0] = vert[1] = vert[2] = nullptr;}
triangle(vertex2dc *v0ptr, vertex2dc *v1ptr, vertex2dc *v2ptr) {set(v0ptr, v1ptr, v2ptr);} triangle(vertex2dc *v0ptr, vertex2dc *v1ptr, vertex2dc *v2ptr) {set(v0ptr, v1ptr, v2ptr);}
@@ -83,10 +90,10 @@ struct triangle
// End triangle definition // End triangle definition
/** /**
* @brief 2D triangulation of given points using the Bowyer-Watson algorithm. * @brief 2D Delaunay triangulation of some given points using the Bowyer-Watson algorithm.
* *
* @param in_verts Input vertexes * @param in_verts Input vertexes. Defined by the user.
* @param out_tris Output triangles * @param out_tris Output triangles. Compute by the function.
*/ */
void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_tris) void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_tris)
{ {
@@ -106,7 +113,7 @@ void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_
double midx = 0.5*(xmin + xmax); double midx = 0.5*(xmin + xmax);
double midy = 0.5*(ymin + ymax); double midy = 0.5*(ymin + ymax);
double maxi_s = std::max(xmax - xmin, ymax - ymin); // use an extra wide rectangle to include all points double maxi_s = std::max(xmax - xmin, ymax - ymin); // use an four times bigger rectangle to include all points
vertex2dc *tmp_vert = nullptr; vertex2dc *tmp_vert = nullptr;
std::vector<vertex2dc*> assit_vert; std::vector<vertex2dc*> assit_vert;
@@ -142,6 +149,8 @@ void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_
{ {
// determine triangles that include the point and add the triangle to the cnst_tri // determine triangles that include the point and add the triangle to the cnst_tri
// Otherwise, add the triangle to the remain_tri // Otherwise, add the triangle to the remain_tri
// this is the part that could take a lot of time if we are working with a large amount of points
// We will fix this later
cnst_tri.clear(); cnst_tri.clear();
remain_tri.clear(); remain_tri.clear();
for (int t = 0; t < exist_tri.size(); ++t) for (int t = 0; t < exist_tri.size(); ++t)
@@ -149,7 +158,7 @@ void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_
dist = (exist_tri[t]->cx - in_verts[i].x) * (exist_tri[t]->cx - in_verts[i].x) + dist = (exist_tri[t]->cx - in_verts[i].x) * (exist_tri[t]->cx - in_verts[i].x) +
(exist_tri[t]->cy - in_verts[i].y) * (exist_tri[t]->cy - in_verts[i].y); (exist_tri[t]->cy - in_verts[i].y) * (exist_tri[t]->cy - in_verts[i].y);
if ((dist - exist_tri[t]->cr) <= ZERO) // inside // think more later if ((dist - exist_tri[t]->cr) <= ZERO) // Points on the circumcircle are also included
{ {
cnst_tri.push_back(exist_tri[t]); cnst_tri.push_back(exist_tri[t]);
} }
@@ -168,7 +177,7 @@ void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_
tmp_edge.set(cnst_tri[c]->vert[e], cnst_tri[c]->vert[(e+1)%3]); tmp_edge.set(cnst_tri[c]->vert[e], cnst_tri[c]->vert[(e+1)%3]);
removed = false; removed = false;
for (e_iter = cnst_edge.begin(); e_iter != cnst_edge.end(); ++e_iter) for (e_iter = cnst_edge.begin(); e_iter != cnst_edge.end(); )
{ {
if (tmp_edge == *e_iter) // duplicate edge, remove from cnst_edge if (tmp_edge == *e_iter) // duplicate edge, remove from cnst_edge
{ {
@@ -176,6 +185,7 @@ void triangulation(std::vector<vertex2dc> &in_verts, std::vector<triangle> &out_
removed = true; removed = true;
break; // no need to search more break; // no need to search more
} }
else e_iter++;
} }
if (!removed) // not a duplicate edge, add to the cnst_edge if (!removed) // not a duplicate edge, add to the cnst_edge

33
demo.cpp
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@@ -3,17 +3,28 @@
int main(int argc, char const *argv[]) int main(int argc, char const *argv[])
{ {
std::vector<vertex2dc> points(10); std::vector<vertex2dc> points(21);
points[0].set(-0.7, -0.3, 0); points[0].set(-0.8, -0.8, 0);
points[1].set(0.1, -0.4, 1); points[1].set(0.4, -1.2, 1);
points[2].set(-0.1, -0.1, 2); points[2].set(1.2, -0.9, 2);
points[3].set(-0.4, 0.0, 3); points[3].set(1.6, 0.1, 3);
points[4].set(-0.4, -0.3, 4); points[4].set(2.5, 0.5, 4);
points[5].set(-0.2, -0.1, 5); points[5].set(4.1, 0.7, 5);
points[6].set(-0.2, -0.6, 6); points[6].set(5.7, 1.8, 6);
points[7].set(-0.2, -0.4, 7); points[7].set(5.1, 3.4, 7);
points[8].set(-0.5, -0.5, 8); points[8].set(2.5, 4.4, 8);
points[9].set(-0.6, -0.2, 9); points[9].set(1.2, 3.7, 9);
points[10].set(-1.2, 3.9, 10);
points[11].set(-3.2, 5.1, 11);
points[12].set(-4.3, 2.9, 12);
points[13].set(-3.1, 0.7, 13);
points[14].set(-1.3, 0.6, 14);
points[15].set(-2.1, 2.9, 15);
points[16].set(0.6, 1.2, 16);
points[17].set(0.1, 2.4, 17);
points[18].set(2.4, 2.8, 18);
points[19].set(3.5, 1.8, 19);
points[20].set(3.6, 3.1, 20);
std::vector<triangle> elements; std::vector<triangle> elements;
triangulation(points, elements); triangulation(points, elements);

74
demo.off
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@@ -1,23 +1,53 @@
OFF OFF
10 11 0 21 30 0
-0.7 -0.3 0 -0.8 -0.8 0
0.1 -0.4 0 0.4 -1.2 0
-0.1 -0.1 0 1.2 -0.9 0
-0.4 0 0 1.6 0.1 0
-0.4 -0.3 0 2.5 0.5 0
-0.2 -0.1 0 4.1 0.7 0
-0.2 -0.6 0 5.7 1.8 0
-0.2 -0.4 0 5.1 3.4 0
-0.5 -0.5 0 2.5 4.4 0
-0.6 -0.2 0 1.2 3.7 0
3 2 3 5 -1.2 3.9 0
3 3 4 5 -3.2 5.1 0
3 1 2 7 -4.3 2.9 0
3 6 1 7 -3.1 0.7 0
3 2 5 7 -1.3 0.6 0
3 5 4 7 -2.1 2.9 0
3 6 7 8 0.6 1.2 0
3 7 4 8 0.1 2.4 0
3 4 3 9 2.4 2.8 0
3 0 8 9 3.5 1.8 0
3 8 4 9 3.6 3.1 0
3 1 2 3
3 3 2 4
3 4 2 5
3 9 8 10
3 10 8 11
3 13 0 14
3 10 11 15
3 11 12 15
3 12 13 15
3 13 14 15
3 0 1 16
3 1 3 16
3 3 4 16
3 14 0 16
3 9 10 17
3 10 15 17
3 15 14 17
3 14 16 17
3 8 9 18
3 16 4 18
3 9 17 18
3 17 16 18
3 5 6 19
3 6 7 19
3 4 5 19
3 18 4 19
3 7 8 20
3 8 18 20
3 18 19 20
3 19 7 20