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-rw-r--r--thirdparty/thekla_atlas/nvmath/ConvexHull.cpp120
1 files changed, 0 insertions, 120 deletions
diff --git a/thirdparty/thekla_atlas/nvmath/ConvexHull.cpp b/thirdparty/thekla_atlas/nvmath/ConvexHull.cpp
deleted file mode 100644
index a4a95dace4..0000000000
--- a/thirdparty/thekla_atlas/nvmath/ConvexHull.cpp
+++ /dev/null
@@ -1,120 +0,0 @@
-// This code is in the public domain -- Ignacio Castaņo <castano@gmail.com>
-
-#include "ConvexHull.h"
-
-#include "Vector.inl"
-
-#include "nvcore/RadixSort.h"
-#include "nvcore/Array.inl"
-
-using namespace nv;
-
-inline static float triangleArea(Vector2::Arg v1, Vector2::Arg v2, Vector2::Arg v3)
-{
- return 0.5f * (v3.x * v1.y + v1.x * v2.y + v2.x * v3.y - v2.x * v1.y - v3.x * v2.y - v1.x * v3.y);
-}
-
-
-// Compute the convex hull using Graham Scan.
-void nv::convexHull(const Array<Vector2> & input, Array<Vector2> & output, float epsilon/*=0*/)
-{
- const uint inputCount = input.count();
-
- Array<float> coords;
- coords.resize(inputCount);
-
- for (uint i = 0; i < inputCount; i++) {
- coords[i] = input[i].x;
- }
-
- RadixSort radix;
- radix.sort(coords);
-
- const uint * ranks = radix.ranks();
-
- Array<Vector2> top(inputCount);
- Array<Vector2> bottom(inputCount);
-
- Vector2 P = input[ranks[0]];
- Vector2 Q = input[ranks[inputCount-1]];
-
- float topy = max(P.y, Q.y);
- float boty = min(P.y, Q.y);
-
- for (uint i = 0; i < inputCount; i++) {
- Vector2 p = input[ranks[i]];
- if (p.y >= boty) top.append(p);
- }
-
- for (uint i = 0; i < inputCount; i++) {
- Vector2 p = input[ranks[inputCount-1-i]];
- if (p.y <= topy) bottom.append(p);
- }
-
- // Filter top list.
- output.clear();
- output.append(top[0]);
- output.append(top[1]);
-
- for (uint i = 2; i < top.count(); ) {
- Vector2 a = output[output.count()-2];
- Vector2 b = output[output.count()-1];
- Vector2 c = top[i];
-
- float area = triangleArea(a, b, c);
-
- if (area >= -epsilon) {
- output.popBack();
- }
-
- if (area < -epsilon || output.count() == 1) {
- output.append(c);
- i++;
- }
- }
-
- uint top_count = output.count();
- output.append(bottom[1]);
-
- // Filter bottom list.
- for (uint i = 2; i < bottom.count(); ) {
- Vector2 a = output[output.count()-2];
- Vector2 b = output[output.count()-1];
- Vector2 c = bottom[i];
-
- float area = triangleArea(a, b, c);
-
- if (area >= -epsilon) {
- output.popBack();
- }
-
- if (area < -epsilon || output.count() == top_count) {
- output.append(c);
- i++;
- }
- }
-
- // Remove duplicate element.
- nvDebugCheck(output.front() == output.back());
- output.popBack();
-}
-
-/*
-void testConvexHull() {
-
- Array<Vector2> points;
- points.append(Vector2(1.00, 1.00));
- points.append(Vector2(0.00, 0.00));
- points.append(Vector2(1.00, 1.00));
- points.append(Vector2(1.00, -1.00));
- points.append(Vector2(2.00, 5.00));
- points.append(Vector2(-5.00, 3.00));
- points.append(Vector2(-4.00, -3.00));
- points.append(Vector2(7.00, -4.00));
-
- Array<Vector2> hull;
- convexHull(points, hull);
-
-}
-*/
-