Integrated Polygon Test

Use calculate traingles and the isInPolygon with theese triangles, this is done because of performance reasons
This commit is contained in:
Sonaion
2019-12-18 16:32:11 +01:00
parent 21ade76563
commit 4953abc791
5 changed files with 150 additions and 22 deletions

View File

@@ -1,2 +1,123 @@
#include"IntelliHelper.h"
#include<algorithm>
#include<queue>
#include<cmath>
std::vector<Triangle> IntelliHelper::calculateTriangles(std::vector<QPoint> polyPoints){
//helper for managing the triangle vertices and their state
struct TriangleHelper{
QPoint vertex;
float interiorAngle;
int index;
bool isTip;
};
//calculates the inner angle of 'point'
auto calculateInner = [](QPoint& point, QPoint& prev, QPoint& post){
QPoint AP(point.x()-prev.x(), point.y()-prev.y());
QPoint BP(point.x()-post.x(), point.y()-post.y());
float topSclar = AP.x()*BP.x()+AP.y()*BP.y();
float absolute = sqrt(pow(AP.x(),2.)+pow(AP.y(),2.))*sqrt(pow(BP.x(),2.)+pow(BP.y(),2.));
return acos(topSclar/absolute);
};
//gets the first element of vec for which element.isTip == true holds
auto getTip= [](const std::vector<TriangleHelper>& vec){
for(auto element:vec){
if(element.isTip){
return element;
}
}
return vec[0];
};
//get the vertex Index bevor index in relation to the container length
auto getPrev = [](int index, int length){
return (index-1)>0?(index-1):(length-1);
};
//get the vertex Index after index in relation to the container lenght
auto getPost = [](int index, int length){
return (index+1)%length;
};
//return if the vertex is a tip
auto isTip = [](float angle){
return angle<180.f;
};
std::vector<TriangleHelper> Vertices;
std::vector<Triangle> Triangles;
//set up all vertices and calculate intirior angle
for(int i=0; i<static_cast<int>(polyPoints.size()); i++){
TriangleHelper helper;
int prev = getPrev(i, static_cast<int>(polyPoints.size()));
int post = getPost(i, static_cast<int>(polyPoints.size()));
helper.vertex = polyPoints[static_cast<size_t>(i)];
helper.index = i;
helper.interiorAngle = calculateInner(polyPoints[static_cast<size_t>(i)],
polyPoints[static_cast<size_t>(prev)],
polyPoints[static_cast<size_t>(post)]);
helper.isTip = isTip(helper.interiorAngle);
Vertices.push_back(helper);
}
//search triangles based on the intirior angles of each vertey
while(Triangles.size() != polyPoints.size()-2){
Triangle tri;
TriangleHelper smallest = getTip(Vertices);
int prev = getPrev(smallest.index, static_cast<int>(Vertices.size()));
int post = getPost(smallest.index, static_cast<int>(Vertices.size()));
//set triangle and push it
tri.A = Vertices[static_cast<size_t>(prev)].vertex;
tri.B = Vertices[static_cast<size_t>(smallest.index)].vertex;
tri.C = Vertices[static_cast<size_t>(post)].vertex;
Triangles.push_back(tri);
//update Vertice array
Vertices.erase(Vertices.begin()+smallest.index);
for(size_t i=static_cast<size_t>(smallest.index); i<Vertices.size(); i++){
Vertices[i].index-=1;
}
//update post und prev index
post = post-1;
prev = prev<smallest.index?prev:(prev-1);
//calcultae neighboors of prev and post to calculate new interior angles
int prevOfPrev = getPrev(prev, static_cast<int>(Vertices.size()));
int postOfPrev = getPost(prev, static_cast<int>(Vertices.size()));
int prevOfPost = getPrev(post, static_cast<int>(Vertices.size()));
int postOfPost = getPost(post, static_cast<int>(Vertices.size()));
//update vertices with interior angles
//updtae prev
Vertices[static_cast<size_t>(prev)].interiorAngle = calculateInner(Vertices[static_cast<size_t>(prev)].vertex,
Vertices[static_cast<size_t>(prevOfPrev)].vertex,
Vertices[static_cast<size_t>(postOfPrev)].vertex);
Vertices[static_cast<size_t>(prev)].isTip = isTip(Vertices[static_cast<size_t>(prev)].interiorAngle);
//update post
Vertices[static_cast<size_t>(post)].interiorAngle = calculateInner(Vertices[static_cast<size_t>(post)].vertex,
Vertices[static_cast<size_t>(prevOfPost)].vertex,
Vertices[static_cast<size_t>(postOfPost)].vertex);
Vertices[static_cast<size_t>(post)].isTip = isTip(Vertices[static_cast<size_t>(post)].interiorAngle);
}
return Triangles;
}
bool IntelliHelper::isInPolygon(std::vector<Triangle> &triangles, QPoint &point){
for(auto triangle : triangles){
if(IntelliHelper::isInTriangle(triangle.A ,triangle.B, triangle.C, point)){
return true;
}
}
return false;
}