new geo functions

changed the walkers
added moving average
fixed the interpolator
new test-cases

geo/Point2.h

@@ -1,6 +1,8 @@
 #ifndef POINT2_H
 #define POINT2_H
 
+#include <cmath>
+
 /**
  * 2D Point
  */
@@ -15,10 +17,35 @@ struct Point2 {
 	/** ctor */
 	Point2(const float x, const float y) : x(x), y(y) {;}
 
+
 	Point2 operator + (const Point2& o) const {return Point2(x+o.x, y+o.y);}
 
 	Point2 operator - (const Point2& o) const {return Point2(x-o.x, y-o.y);}
 
+	Point2 operator * (const float v) const {return Point2(v*x, v*y);}
+
+	Point2 operator / (const float v) const {return Point2(x/v, y/v);}
+
+
+	Point2& operator *= (const float v) {x*=v; y*=v; return *this;}
+
+	Point2& operator /= (const float v) {x/=v; y/=v; return *this;}
+
+	Point2& operator += (const Point2& o) {x+=o.x; y+=o.y; return *this;}
+
+	Point2& operator -= (const Point2& o) {x-=o.x; y-=o.y; return *this;}
+
+
+	bool operator == (const Point2& o) const {return x==o.x && y==o.y;}
+
+
+	/** get the distance between this point and the other one */
+	float getDistance(const Point2& o) const {
+		const float dx = x - o.x;
+		const float dy = y - o.y;
+		return std::sqrt(dx*dx + dy*dy);
+	}
+
 };
 
 #endif // POINT2_H

geo/Point3.h

@@ -3,6 +3,7 @@
 
 #include "../Assertions.h"
 #include <cmath>
+#include "Point2.h"
 
 /**
  * 3D Point
@@ -29,6 +30,7 @@ struct Point3 {
 
 	Point3 operator / (const float v) const {return Point3(x/v, y/v, z/v);}
 
+
 	Point3& operator *= (const float v) {x*=v; y*=v; z*=v; return *this;}
 
 	Point3& operator /= (const float v) {x/=v; y/=v; z/=v; return *this;}
@@ -37,8 +39,11 @@ struct Point3 {
 
 	Point3& operator -= (const Point3& o) {x-=o.x; y-=o.y; z-=o.z; return *this;}
 
+
 	bool operator == (const Point3& o) const {return x==o.x && y==o.y && z==o.z;}
 
+	Point2 xy() const {return Point2(x,y);}
+
 	/** read-only array access */
 	float operator [] (const int idx) const {
 		Assert::isBetween(idx, 0, 2, "index out of bounds");

grid/walk/GridWalkRandomHeadingUpdate.h

@@ -30,7 +30,7 @@ template <typename T> class GridWalkRandomHeadingUpdate : public GridWalk<T> {
 private:
 
 	/** per-edge: change heading with this sigma */
-	static constexpr float HEADING_CHANGE_SIGMA = Angle::degToRad(8);
+	static constexpr float HEADING_CHANGE_SIGMA = Angle::degToRad(10);
 
 	/** fast random-number-generator */
 	std::minstd_rand gen;

math/Interpolator.h

@@ -2,6 +2,10 @@
 #define INTERPOLATOR_H
 
 #include "../Assertions.h"
+#include "../Exception.h"
+
+#include <vector>
+#include <algorithm>
 
 /**
  * interpolate between two adjacent values based on their key
@@ -11,40 +15,55 @@ template <typename Key, typename Value> class Interpolator {
 public:
 
 	/** value at key */
-	struct Entry {
+	struct InterpolatorEntry {
 		Key key;
 		Value value;
-		Entry(const Key key, const Value& pos) : key(key), value(value) {;}
+		InterpolatorEntry(const Key key, const Value& value) : key(key), value(value) {;}
 	};
 
 protected:
 
 	/** all added entries, SORTED by their key */
-	std::vector<Entry> entries;
+	std::vector<InterpolatorEntry> entries;
 
 public:
 
 	/** add a new value with its key. entries must be added in sorted order! */
 	void add(const Key key, const Value& value) {
 		Assert::isTrue (entries.empty() || entries.back().key < key, "entries must be ordered!");
-		entries.push_back(Entry(key, value));
+		entries.push_back(InterpolatorEntry(key, value));
 	}
 
 	/** get the interpolated value for the given key */
 	Value get(const Key key) const {
-		const int idx1 = getIdx(key);
-		const int idx2 = idx1+1;
+
+		const int idx2 = getIdxAfter(key);
+		if (idx2 == 0)	{return entries.front().value;}			// key < everything within the list
+		if (idx2 == -1)	{return entries.back().value;}			// key > everything within the list
+
+		// interpolate
+		const int idx1 = (idx2 > 0) ? (idx2 - 1) : (idx2);
 		const float percent = (key - entries[idx1].key) / (float) (entries[idx2].key - entries[idx1].key);
 		return entries[idx1].value + (entries[idx2].value - entries[idx1].value) * percent;
+
 	}
 
+protected:
+
 	/** get the nearest index for the given key */
-	int getIdx(const Key key) const {
-		// TODO: use O(log(n)) search here!
-		for (size_t i = 0; i < entries.size(); ++i) {
-			if (entries[i].key > key) {return i-1;}
-		}
-		throw "should not happen";
+	int getIdxAfter(const Key key) const {
+
+		// compare key against one entry
+		static auto comp = [] (const Key& key, const InterpolatorEntry& ie1) {return key < ie1.key;};
+
+		// find the next entry > than key
+		const auto it = std::upper_bound(entries.begin(), entries.end(), key, comp);
+
+		// none found? (key > everything within the list)
+		return (it == entries.end()) ? (-1) : (it-entries.begin());
+		//if (it == entries.end()) {throw Exception("key not found: " + std::to_string(key));}
+		//return it - entries.begin();
+
 	}
 
 };

math/MovingAVG.h

@@ -0,0 +1,58 @@
+#ifndef MOVINGAVG_H
+#define MOVINGAVG_H
+
+#include <vector>
+
+template <typename T> class MovingAVG {
+
+private:
+
+	/** up to "size" elements */
+	std::vector<T> values;
+
+	/** track the current sum of the vector's values */
+	T curSum = 0;
+
+	/** the number of elements to average */
+	int size;
+
+public:
+
+	/** ctor */
+	MovingAVG(const int size) : size(size) {;}
+
+	/** add a new value */
+	void add(const T val) {
+
+		// add new value
+		values.push_back(val);
+		curSum += val;
+
+		// too many values?
+		if ((int) values.size() > size) {
+			curSum -= values.front();
+			values.erase(values.begin());
+		}
+
+	}
+
+	/** get the current average */
+	T get() const {
+		return curSum / values.size();
+	}
+
+
+	/** get the number of used entries */
+	int getNumUsed() const {
+		return (int) values.size();
+	}
+
+	/** get number of entries to average */
+	int getSize() const {
+		return size;
+	}
+
+
+};
+
+#endif // MOVINGAVG_H

tests/grid/TestWalk.cpp

@@ -12,8 +12,8 @@
 #include "../../grid/walk/GridWalkWeighted.h"
 #include "../../grid/walk/GridWalkLightAtTheEndOfTheTunnel.h"
 
-TEST(Walk, plot) {
-//TEST(Walk, DISABLED_plot) {
+//TEST(Walk, plot) {
+TEST(Walk, DISABLED_plot) {
 
 	Grid<GP> g(20);
 	GridFactory<GP> gf(g);

tests/math/TestInterpolator.cpp

@@ -0,0 +1,40 @@
+#ifdef WITH_TESTS
+
+#include "../Tests.h"
+#include "../../math/Interpolator.h"
+
+TEST(Interpolator, addAndGet) {
+
+	Interpolator<int, float> interp;
+	interp.add(10, 20);
+	interp.add(20, 30);
+	interp.add(30, 50);
+
+	ASSERT_EQ(20, std::round(interp.get(0)));		// before
+	ASSERT_EQ(20, std::round(interp.get(10)));		// matches
+
+	ASSERT_EQ(21, std::round(interp.get(11)));
+	ASSERT_EQ(25, std::round(interp.get(15)));
+	ASSERT_EQ(29, std::round(interp.get(19)));
+
+	ASSERT_EQ(30, std::round(interp.get(20)));		//matches
+
+	ASSERT_EQ(40, std::round(interp.get(25)));
+	ASSERT_EQ(42, std::round(interp.get(26)));
+
+	ASSERT_EQ(50, std::round(interp.get(30)));		// matches
+	ASSERT_EQ(50, std::round(interp.get(99)));		// after
+
+}
+
+TEST(Interpolator, sanity) {
+
+	Interpolator<int, int> interp;
+	interp.add(10, 20);
+	ASSERT_THROW( interp.add(10,30), std::exception );
+	interp.add(12, 22);
+	ASSERT_THROW( interp.add(11,21), std::exception );
+
+}
+
+#endif

tests/math/TestMovingAVG.cpp

@@ -0,0 +1,21 @@
+#ifdef WITH_TESTS
+
+#include "../Tests.h"
+#include "../../math/MovingAVG.h"
+
+TEST(MovingAVG, add) {
+
+	MovingAVG<float> avg(3);
+
+	avg.add(1); ASSERT_EQ(1, avg.get());
+	avg.add(1); ASSERT_EQ(1, avg.get());
+	avg.add(1); ASSERT_EQ(1, avg.get());
+
+	avg.add(4); ASSERT_EQ(2, avg.get());
+	avg.add(4); ASSERT_EQ(3, avg.get());
+
+	avg.add(4); ASSERT_EQ(4, avg.get());
+
+}
+
+#endif