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POC++ vector loses data in recursive function
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  1. POC++ vector loses data in recursive function
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    copied!<p>I am very new to C++ and I am trying to implement a TriangleDynamic object that can recursively split itself using a function called splitTriangleProject. It splits itself into four smaller TriangleDynamic objects (and projects the vertices of the new triangles onto a sphere with a given radius and origin, but I believe this is beside the point), pushes the newly created triangles into a vector that is part of the member data of the original object. The vector member data is called subTriangles. Then each subTriangle recalls the splitTriangleProject function until a certain "level" of splits has occurred. </p> <p>The issue I am having is that only the first level of splitting is actually properly pushing to the subTriangles vector. I am certain that the issue has to do with the vectors going out of scope, or maybe the TriangleDynamic going out of scope. I imagine there is some solution with pointers. If anyone could help, it would be much appreciated.</p> <p>Here is my TriangleDynamic declaration:</p> <pre><code>class TriangleDynamic { public: TriangleDynamic(const Point &amp;P1, const Point &amp;P2, const Point &amp;P3); TriangleDynamic(); ~TriangleDynamic(){} void printTriangle(); void splitTriangleProject( int currentLevel, int maxLevel, const Point &amp;org, double radius); void init(); bool operator&lt;(const TriangleDynamic&amp;); bool operator&gt;(const TriangleDynamic&amp;); Line edge1; Line edge2; Line edge3; Point p1; Point p2; Point p3; Vect normal; bool lowestLevel; vector&lt;TriangleDynamic&gt; subTriangles; static int numTriangles; int triangleId; }; int TriangleDynamic::numTriangles = 0; </code></pre> <p>and the constructors:</p> <pre><code>// constructor for the TriangleDynamic object TriangleDynamic::TriangleDynamic(const Point &amp;P1, const Point &amp;P2, const Point &amp;P3) { p1 = P1; p2 = P2; p3 = P3; init(); } TriangleDynamic::TriangleDynamic() { p1 = Point(0,0,0); p2 = Point(0,0,1); p3 = Point(0,1,0); init(); } void TriangleDynamic::init() { edge1 = Line(p1,p2); edge2 = Line(p2,p3); edge3 = Line(p3,p1); Vect U = p2.minus( p1); Vect V = p3.minus(p1); normal = U.cross(V); lowestLevel = true; triangleId = numTriangles + 1; numTriangles = triangleId; } </code></pre> <p>Here is my splitTriangleProject function:</p> <pre><code>void TriangleDynamic::splitTriangleProject(int currentLevel, int maxLevel, const Point &amp;org, double radius) { if ( currentLevel &lt; maxLevel) { lowestLevel = false; Point worldOrigin = Point(0,0,0); double edge1MidMag = (edge1.midpoint - org).distance(worldOrigin) ; double edge2MidMag = (edge2.midpoint - org).distance(worldOrigin) ; double edge3MidMag = (edge3.midpoint - org).distance(worldOrigin) ; Point newEdge1Mid = (((edge1.midpoint) * radius )/ edge1MidMag) + org; Point newEdge2Mid = (((edge2.midpoint) * radius )/ edge2MidMag) + org; Point newEdge3Mid = (((edge3.midpoint) * radius )/ edge3MidMag) + org; TriangleDynamic t1(p1 , newEdge1Mid , newEdge3Mid); subTriangles.push_back(t1); TriangleDynamic t2(newEdge1Mid, p2, newEdge2Mid); subTriangles.push_back(t2); TriangleDynamic t3(newEdge3Mid, newEdge2Mid, p3); subTriangles.push_back(t3); TriangleDynamic t4(newEdge1Mid, newEdge2Mid, newEdge3Mid); subTriangles.push_back(t4); t1.splitTriangleProject( currentLevel + 1, maxLevel, org, radius); t2.splitTriangleProject( currentLevel + 1, maxLevel, org, radius); t3.splitTriangleProject( currentLevel + 1, maxLevel, org, radius); t4.splitTriangleProject( currentLevel + 1, maxLevel, org, radius); } } </code></pre> <p>Here is a function for recursively printing the triangleDynamic when it's done:</p> <pre><code>void TriangleDynamic::printTriangle() { cout&lt;&lt; "p1"; p1.printPoint(); cout &lt;&lt; "\np2"; p2.printPoint(); cout &lt;&lt; "\np3"; p3.printPoint(); cout &lt;&lt; "\n\n"; if(!lowestLevel) { int ctr; for (ctr=0; ctr&lt;=subTriangles.size()-1; ctr++) { cout &lt;&lt; "subTriangle\n"; subTriangles[ctr].printTriangle(); } } } </code></pre> <p>Here is how I call it in my main:</p> <pre><code>int main() { TriangleDynamic t = TriangleDynamic(); t.splitTriangleProject(0,3,Point(), 1); t.printTriangle(); cin.get(); return 0; } </code></pre> <p>I think I've posted too much at this point. Any help is appreciated, thanks in advance.</p>
 

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