using UnityEngine;
using System.Collections.Generic;
using System;
namespace Pathfinding {
using Pathfinding.Util;
using Unity.Mathematics;
using Unity.Burst;
using Pathfinding.Graphs.Navmesh;
/// Contains various spline functions.
public static class AstarSplines {
public static Vector3 CatmullRom (Vector3 previous, Vector3 start, Vector3 end, Vector3 next, float elapsedTime) {
// References used:
// p.266 GemsV1
//
// tension is often set to 0.5 but you can use any reasonable value:
// http://www.cs.cmu.edu/~462/projects/assn2/assn2/catmullRom.pdf
//
// bias and tension controls:
// http://local.wasp.uwa.edu.au/~pbourke/miscellaneous/interpolation/
float percentComplete = elapsedTime;
float percentCompleteSquared = percentComplete * percentComplete;
float percentCompleteCubed = percentCompleteSquared * percentComplete;
return
previous * (-0.5F*percentCompleteCubed +
percentCompleteSquared -
0.5F*percentComplete) +
start *
(1.5F*percentCompleteCubed +
-2.5F*percentCompleteSquared + 1.0F) +
end *
(-1.5F*percentCompleteCubed +
2.0F*percentCompleteSquared +
0.5F*percentComplete) +
next *
(0.5F*percentCompleteCubed -
0.5F*percentCompleteSquared);
}
/// Returns a point on a cubic bezier curve. t is clamped between 0 and 1
public static Vector3 CubicBezier (Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t) {
t = Mathf.Clamp01(t);
float t2 = 1-t;
return t2*t2*t2 * p0 + 3 * t2*t2 * t * p1 + 3 * t2 * t*t * p2 + t*t*t * p3;
}
/// Returns the derivative for a point on a cubic bezier curve. t is clamped between 0 and 1
public static Vector3 CubicBezierDerivative (Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t) {
t = Mathf.Clamp01(t);
float t2 = 1-t;
return 3*t2*t2*(p1-p0) + 6*t2*t*(p2 - p1) + 3*t*t*(p3 - p2);
}
/// Returns the second derivative for a point on a cubic bezier curve. t is clamped between 0 and 1
public static Vector3 CubicBezierSecondDerivative (Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t) {
t = Mathf.Clamp01(t);
float t2 = 1-t;
return 6*t2*(p2 - 2*p1 + p0) + 6*t*(p3 - 2*p2 + p1);
}
}
///
/// Various vector math utility functions.
/// Version: A lot of functions in the Polygon class have been moved to this class
/// the names have changed slightly and everything now consistently assumes a left handed
/// coordinate system now instead of sometimes using a left handed one and sometimes
/// using a right handed one. This is why the 'Left' methods in the Polygon class redirect
/// to methods named 'Right'. The functionality is exactly the same.
///
/// Note the difference between segments and lines. Lines are infinitely
/// long but segments have only a finite length.
///
public static class VectorMath {
///
/// Complex number multiplication.
/// Returns: a * b
///
/// Used to rotate vectors in an efficient way.
///
/// See: https://en.wikipedia.org/wiki/Complex_number
///
public static Vector2 ComplexMultiply (Vector2 a, Vector2 b) {
return new Vector2(a.x * b.x - a.y * b.y, a.x * b.y + a.y * b.x);
}
///
/// Complex number multiplication.
/// Returns: a * b
///
/// Used to rotate vectors in an efficient way.
///
/// See: https://en.wikipedia.org/wiki/Complex_number
///
public static float2 ComplexMultiply (float2 a, float2 b) {
return a.x*b + a.y*new float2(-b.y, b.x);
}
///
/// Complex number multiplication.
/// Returns: a * conjugate(b)
///
/// Used to rotate vectors in an efficient way.
///
/// See: https://en.wikipedia.org/wiki/Complex_number
/// See: https://en.wikipedia.org/wiki/Complex_conjugate
///
public static float2 ComplexMultiplyConjugate (float2 a, float2 b) {
return new float2(a.x * b.x + a.y * b.y, a.y * b.x - a.x * b.y);
}
///
/// Complex number multiplication.
/// Returns: a * conjugate(b)
///
/// Used to rotate vectors in an efficient way.
///
/// See: https://en.wikipedia.org/wiki/Complex_number
/// See: https://en.wikipedia.org/wiki/Complex_conjugate
///
public static Vector2 ComplexMultiplyConjugate (Vector2 a, Vector2 b) {
return new Vector2(a.x * b.x + a.y * b.y, a.y * b.x - a.x * b.y);
}
///
/// Returns the closest point on the line.
/// The line is treated as infinite.
/// See: ClosestPointOnSegment
/// See: ClosestPointOnLineFactor
///
public static Vector3 ClosestPointOnLine (Vector3 lineStart, Vector3 lineEnd, Vector3 point) {
Vector3 lineDirection = Vector3.Normalize(lineEnd - lineStart);
float dot = Vector3.Dot(point - lineStart, lineDirection);
return lineStart + (dot*lineDirection);
}
///
/// Factor along the line which is closest to the point.
/// Returned value is in the range [0,1] if the point lies on the segment otherwise it just lies on the line.
/// The closest point can be calculated using (end-start)*factor + start.
///
/// See: ClosestPointOnLine
/// See: ClosestPointOnSegment
///
public static float ClosestPointOnLineFactor (Vector3 lineStart, Vector3 lineEnd, Vector3 point) {
var dir = lineEnd - lineStart;
float sqrMagn = dir.sqrMagnitude;
if (sqrMagn <= 0.000001f) return 0;
return Vector3.Dot(point - lineStart, dir) / sqrMagn;
}
///
/// Factor along the line which is closest to the point.
/// Returned value is in the range [0,1] if the point lies on the segment otherwise it just lies on the line.
/// The closest point can be calculated using (end-start)*factor + start
///
public static float ClosestPointOnLineFactor (float3 lineStart, float3 lineEnd, float3 point) {
var lineDirection = lineEnd - lineStart;
var sqrMagn = math.dot(lineDirection, lineDirection);
return math.select(0, math.dot(point - lineStart, lineDirection) / sqrMagn, sqrMagn > 0.000001f);
}
///
/// Factor along the line which is closest to the point.
/// Returned value is in the range [0,1] if the point lies on the segment otherwise it just lies on the line.
/// The closest point can be calculated using (end-start)*factor + start
///
public static float ClosestPointOnLineFactor (Int3 lineStart, Int3 lineEnd, Int3 point) {
var lineDirection = lineEnd - lineStart;
float magn = lineDirection.sqrMagnitude;
float closestPoint = (float)Int3.DotLong(point - lineStart, lineDirection);
if (magn != 0) closestPoint /= magn;
return closestPoint;
}
///
/// Factor of the nearest point on the segment.
/// Returned value is in the range [0,1] if the point lies on the segment otherwise it just lies on the line.
/// The closest point can be calculated using (end-start)*factor + start;
///
public static float ClosestPointOnLineFactor (Int2 lineStart, Int2 lineEnd, Int2 point) {
var lineDirection = lineEnd - lineStart;
double magn = lineDirection.sqrMagnitudeLong;
double closestPoint = Int2.DotLong(point - lineStart, lineDirection);
if (magn != 0) closestPoint /= magn;
return (float)closestPoint;
}
///
/// Returns the closest point on the segment.
/// The segment is NOT treated as infinite.
/// See: ClosestPointOnLine
/// See: ClosestPointOnSegmentXZ
///
public static Vector3 ClosestPointOnSegment (Vector3 lineStart, Vector3 lineEnd, Vector3 point) {
var dir = lineEnd - lineStart;
float sqrMagn = dir.sqrMagnitude;
if (sqrMagn <= 0.000001) return lineStart;
float factor = Vector3.Dot(point - lineStart, dir) / sqrMagn;
return lineStart + Mathf.Clamp01(factor)*dir;
}
///
/// Returns the closest point on the segment in the XZ plane.
/// The y coordinate of the result will be the same as the y coordinate of the point parameter.
///
/// The segment is NOT treated as infinite.
/// See: ClosestPointOnSegment
/// See: ClosestPointOnLine
///
public static Vector3 ClosestPointOnSegmentXZ (Vector3 lineStart, Vector3 lineEnd, Vector3 point) {
lineStart.y = point.y;
lineEnd.y = point.y;
Vector3 fullDirection = lineEnd-lineStart;
Vector3 fullDirection2 = fullDirection;
fullDirection2.y = 0;
float magn = fullDirection2.magnitude;
Vector3 lineDirection = magn > float.Epsilon ? fullDirection2/magn : Vector3.zero;
float closestPoint = Vector3.Dot((point-lineStart), lineDirection);
return lineStart+(Mathf.Clamp(closestPoint, 0.0f, fullDirection2.magnitude)*lineDirection);
}
///
/// Returns the approximate shortest squared distance between x,z and the segment p-q.
/// The segment is not considered infinite.
/// This function is not entirely exact, but it is about twice as fast as DistancePointSegment2.
/// TODO: Is this actually approximate? It looks exact.
///
public static float SqrDistancePointSegmentApproximate (int x, int z, int px, int pz, int qx, int qz) {
float pqx = (float)(qx - px);
float pqz = (float)(qz - pz);
float dx = (float)(x - px);
float dz = (float)(z - pz);
float d = pqx*pqx + pqz*pqz;
float t = pqx*dx + pqz*dz;
if (d > 0)
t /= d;
if (t < 0)
t = 0;
else if (t > 1)
t = 1;
dx = px + t*pqx - x;
dz = pz + t*pqz - z;
return dx*dx + dz*dz;
}
///
/// Returns the approximate shortest squared distance between x,z and the segment p-q.
/// The segment is not considered infinite.
/// This function is not entirely exact, but it is about twice as fast as DistancePointSegment2.
/// TODO: Is this actually approximate? It looks exact.
///
public static float SqrDistancePointSegmentApproximate (Int3 a, Int3 b, Int3 p) {
float pqx = (float)(b.x - a.x);
float pqz = (float)(b.z - a.z);
float dx = (float)(p.x - a.x);
float dz = (float)(p.z - a.z);
float d = pqx*pqx + pqz*pqz;
float t = pqx*dx + pqz*dz;
if (d > 0)
t /= d;
if (t < 0)
t = 0;
else if (t > 1)
t = 1;
dx = a.x + t*pqx - p.x;
dz = a.z + t*pqz - p.z;
return dx*dx + dz*dz;
}
///
/// Returns the squared distance between p and the segment a-b.
/// The line is not considered infinite.
///
public static float SqrDistancePointSegment (Vector3 a, Vector3 b, Vector3 p) {
var nearest = ClosestPointOnSegment(a, b, p);
return (nearest-p).sqrMagnitude;
}
///
/// 3D minimum distance between 2 segments.
/// Input: two 3D line segments S1 and S2
/// Returns: the shortest squared distance between S1 and S2
///
public static float SqrDistanceSegmentSegment (Vector3 s1, Vector3 e1, Vector3 s2, Vector3 e2) {
Vector3 dir1 = e1 - s1;
Vector3 dir2 = e2 - s2;
Vector3 startOffset = s1 - s2;
double dir1sq = Vector3.Dot(dir1, dir1); // always >= 0
double b = Vector3.Dot(dir1, dir2);
double dir2sq = Vector3.Dot(dir2, dir2); // always >= 0
double d = Vector3.Dot(dir1, startOffset);
double e = Vector3.Dot(dir2, startOffset);
double D = dir1sq*dir2sq - b*b; // always >= 0
double sc, sN, sD = D; // sc = sN / sD, default sD = D >= 0
double tc, tN, tD = D; // tc = tN / tD, default tD = D >= 0
// compute the line parameters of the two closest points
// D is approximately |dir1|^2|dir2|^2*(1-cos^2 alpha), where alpha is the angle between the lines
if (D < 0.000001 * dir1sq*dir2sq) { // the lines are almost parallel
sN = 0.0f; // force using point P0 on segment S1
sD = 1.0f; // to prevent possible division by 0.0 later
tN = e;
tD = dir2sq;
} else { // get the closest points on the infinite lines
sN = (b*e - dir2sq*d);
tN = (dir1sq*e - b*d);
if (sN < 0.0) { // sc < 0 => the s=0 edge is visible
sN = 0.0;
tN = e;
tD = dir2sq;
} else if (sN > sD) { // sc > 1 => the s=1 edge is visible
sN = sD;
tN = e + b;
tD = dir2sq;
}
}
if (tN < 0.0) { // tc < 0 => the t=0 edge is visible
tN = 0.0;
// recompute sc for this edge
if (-d < 0.0f)
sN = 0.0f;
else if (-d > dir1sq)
sN = sD;
else {
sN = -d;
sD = dir1sq;
}
} else if (tN > tD) { // tc > 1 => the t=1 edge is visible
tN = tD;
// recompute sc for this edge
if ((-d + b) < 0.0f)
sN = 0;
else if ((-d + b) > dir1sq)
sN = sD;
else {
sN = (-d + b);
sD = dir1sq;
}
}
// finally do the division to get sc and tc
sc = (Math.Abs(sN) < 0.00001f ? 0.0 : sN / sD);
tc = (Math.Abs(tN) < 0.00001f ? 0.0 : tN / tD);
// get the difference of the two closest points
Vector3 dP = startOffset + ((float)sc * dir1) - ((float)tc * dir2); // = S1(sc) - S2(tc)
return dP.sqrMagnitude; // return the closest distance
}
///
/// Determinant of the 2x2 matrix [c1, c2].
///
/// This is useful for many things, like calculating distances between lines and points.
///
/// Equivalent to Cross(new float3(c1, 0), new float 3(c2, 0)).z
///
public static float Determinant (float2 c1, float2 c2) {
return c1.x*c2.y - c1.y*c2.x;
}
/// Squared distance between two points in the XZ plane
public static float SqrDistanceXZ (Vector3 a, Vector3 b) {
var delta = a-b;
return delta.x*delta.x+delta.z*delta.z;
}
///
/// Signed area of a triangle in the XZ plane multiplied by 2.
/// This will be negative for clockwise triangles and positive for counter-clockwise ones
///
public static long SignedTriangleAreaTimes2XZ (Int3 a, Int3 b, Int3 c) {
return (long)(b.x - a.x) * (long)(c.z - a.z) - (long)(c.x - a.x) * (long)(b.z - a.z);
}
///
/// Signed area of a triangle in the XZ plane multiplied by 2.
/// This will be negative for clockwise triangles and positive for counter-clockwise ones.
///
public static float SignedTriangleAreaTimes2XZ (Vector3 a, Vector3 b, Vector3 c) {
return (b.x - a.x) * (c.z - a.z) - (c.x - a.x) * (b.z - a.z);
}
///
/// Returns if p lies on the right side of the line a - b.
/// Uses XZ space. Does not return true if the points are colinear.
///
public static bool RightXZ (Vector3 a, Vector3 b, Vector3 p) {
return (b.x - a.x) * (p.z - a.z) - (p.x - a.x) * (b.z - a.z) < -float.Epsilon;
}
///
/// Returns if p lies on the right side of the line a - b.
/// Uses XZ space. Does not return true if the points are colinear.
///
public static bool RightXZ (Int3 a, Int3 b, Int3 p) {
return (long)(b.x - a.x) * (long)(p.z - a.z) - (long)(p.x - a.x) * (long)(b.z - a.z) < 0;
}
///
/// Returns which side of the line a - b that p lies on.
/// Uses XZ space.
///
public static Side SideXZ (Int3 a, Int3 b, Int3 p) {
var s = (long)(b.x - a.x) * (long)(p.z - a.z) - (long)(p.x - a.x) * (long)(b.z - a.z);
return s > 0 ? Side.Left : (s < 0 ? Side.Right : Side.Colinear);
}
///
/// Returns if p lies on the right side of the line a - b.
/// Also returns true if the points are colinear.
///
public static bool RightOrColinear (Vector2 a, Vector2 b, Vector2 p) {
return (b.x - a.x) * (p.y - a.y) - (p.x - a.x) * (b.y - a.y) <= 0;
}
///
/// Returns if p lies on the right side of the line a - b.
/// Also returns true if the points are colinear.
///
public static bool RightOrColinear (Int2 a, Int2 b, Int2 p) {
return (long)(b.x - a.x) * (long)(p.y - a.y) - (long)(p.x - a.x) * (long)(b.y - a.y) <= 0;
}
///
/// Returns if p lies on the left side of the line a - b.
/// Uses XZ space. Also returns true if the points are colinear.
///
public static bool RightOrColinearXZ (Vector3 a, Vector3 b, Vector3 p) {
return (b.x - a.x) * (p.z - a.z) - (p.x - a.x) * (b.z - a.z) <= 0;
}
///
/// Returns if p lies on the left side of the line a - b.
/// Uses XZ space. Also returns true if the points are colinear.
///
public static bool RightOrColinearXZ (Int3 a, Int3 b, Int3 p) {
return (long)(b.x - a.x) * (long)(p.z - a.z) - (long)(p.x - a.x) * (long)(b.z - a.z) <= 0;
}
///
/// Returns if the points a in a clockwise order.
/// Will return true even if the points are colinear or very slightly counter-clockwise
/// (if the signed area of the triangle formed by the points has an area less than or equals to float.Epsilon)
///
public static bool IsClockwiseMarginXZ (Vector3 a, Vector3 b, Vector3 c) {
return (b.x-a.x)*(c.z-a.z)-(c.x-a.x)*(b.z-a.z) <= float.Epsilon;
}
/// Returns if the points a in a clockwise order
public static bool IsClockwiseXZ (Vector3 a, Vector3 b, Vector3 c) {
return (b.x-a.x)*(c.z-a.z)-(c.x-a.x)*(b.z-a.z) < 0;
}
/// Returns if the points a in a clockwise order
public static bool IsClockwiseXZ (Int3 a, Int3 b, Int3 c) {
return RightXZ(a, b, c);
}
/// Returns true if the points a in a clockwise order or if they are colinear
public static bool IsClockwiseOrColinearXZ (Int3 a, Int3 b, Int3 c) {
return RightOrColinearXZ(a, b, c);
}
/// Returns true if the points a in a clockwise order or if they are colinear
public static bool IsClockwiseOrColinear (Int2 a, Int2 b, Int2 c) {
return RightOrColinear(a, b, c);
}
/// Returns if the points are colinear (lie on a straight line)
public static bool IsColinear (Vector3 a, Vector3 b, Vector3 c) {
var lhs = b - a;
var rhs = c - a;
// Take the cross product of lhs and rhs
// The magnitude of the cross product will be zero if the points a,b,c are colinear
float x = lhs.y * rhs.z - lhs.z * rhs.y;
float y = lhs.z * rhs.x - lhs.x * rhs.z;
float z = lhs.x * rhs.y - lhs.y * rhs.x;
float v = x*x + y*y + z*z;
float lengthsq = lhs.sqrMagnitude * rhs.sqrMagnitude;
// Epsilon not chosen with much thought, just that float.Epsilon was a bit too small.
return v <= math.sqrt(lengthsq) * 0.0001f || lengthsq == 0.0f;
}
/// Returns if the points are colinear (lie on a straight line)
public static bool IsColinear (Vector2 a, Vector2 b, Vector2 c) {
float v = (b.x-a.x)*(c.y-a.y)-(c.x-a.x)*(b.y-a.y);
// Epsilon not chosen with much thought, just that float.Epsilon was a bit too small.
return v <= 0.0001f && v >= -0.0001f;
}
/// Returns if the points are colinear (lie on a straight line)
public static bool IsColinearXZ (Int3 a, Int3 b, Int3 c) {
return (long)(b.x - a.x) * (long)(c.z - a.z) - (long)(c.x - a.x) * (long)(b.z - a.z) == 0;
}
/// Returns if the points are colinear (lie on a straight line)
public static bool IsColinearXZ (Vector3 a, Vector3 b, Vector3 c) {
float v = (b.x-a.x)*(c.z-a.z)-(c.x-a.x)*(b.z-a.z);
// Epsilon not chosen with much thought, just that float.Epsilon was a bit too small.
return v <= 0.0000001f && v >= -0.0000001f;
}
/// Returns if the points are colinear (lie on a straight line)
public static bool IsColinearAlmostXZ (Int3 a, Int3 b, Int3 c) {
long v = (long)(b.x - a.x) * (long)(c.z - a.z) - (long)(c.x - a.x) * (long)(b.z - a.z);
return v > -1 && v < 1;
}
///
/// Returns if the line segment start2 - end2 intersects the line segment start1 - end1.
/// If only the endpoints coincide, the result is undefined (may be true or false).
///
public static bool SegmentsIntersect (Int2 start1, Int2 end1, Int2 start2, Int2 end2) {
return RightOrColinear(start1, end1, start2) != RightOrColinear(start1, end1, end2) && RightOrColinear(start2, end2, start1) != RightOrColinear(start2, end2, end1);
}
///
/// Returns if the line segment start2 - end2 intersects the line segment start1 - end1.
/// If only the endpoints coincide, the result is undefined (may be true or false).
///
/// Note: XZ space
///
public static bool SegmentsIntersectXZ (Int3 start1, Int3 end1, Int3 start2, Int3 end2) {
return RightOrColinearXZ(start1, end1, start2) != RightOrColinearXZ(start1, end1, end2) && RightOrColinearXZ(start2, end2, start1) != RightOrColinearXZ(start2, end2, end1);
}
///
/// Returns if the two line segments intersects. The lines are NOT treated as infinite (just for clarification)
/// See: IntersectionPoint
///
public static bool SegmentsIntersectXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2) {
Vector3 dir1 = end1-start1;
Vector3 dir2 = end2-start2;
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
return false;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float nom2 = dir1.x*(start1.z-start2.z) - dir1.z * (start1.x - start2.x);
float u = nom/den;
float u2 = nom2/den;
if (u < 0F || u > 1F || u2 < 0F || u2 > 1F) {
return false;
}
return true;
}
///
/// Calculates the intersection points between a "capsule" (segment expanded by a radius), and a line.
///
/// Returns: (t1, t2), the intersection points on the form lineStart + lineDir*t. Where t2 >= t1. If t2 < t1 then there are no intersections.
///
/// Center of the capsule's first circle
/// Main axis of the capsule. Must be normalized.
/// Distance betwen the capsule's circle centers.
/// A point on the line
/// The (normalized) direction of the line.
/// The radius of the circle.
public static float2 CapsuleLineIntersectionFactors (float2 capsuleStart, float2 capsuleDir, float capsuleLength, float2 lineStart, float2 lineDir, float radius) {
var cosAlpha = math.dot(capsuleDir, lineDir);
var sinAlpha = math.sqrt(1.0f - cosAlpha*cosAlpha);
var tmin = float.PositiveInfinity;
var tmax = float.NegativeInfinity;
if (LineCircleIntersectionFactors(lineStart - capsuleStart, lineDir, radius, out float t11, out float t12)) {
tmin = math.min(tmin, t11);
tmax = math.max(tmax, t12);
}
if (LineCircleIntersectionFactors(lineStart - (capsuleStart + capsuleDir*capsuleLength), lineDir, radius, out float t21, out float t22)) {
tmin = math.min(tmin, t21);
tmax = math.max(tmax, t22);
}
if (LineLineIntersectionFactor(capsuleStart, capsuleDir, lineStart, lineDir, out float ucenter)) {
var normal = new float2(-capsuleDir.y, capsuleDir.x);
var offset = radius * cosAlpha / sinAlpha;
var side = math.sign(capsuleDir.y*lineDir.x - capsuleDir.x*lineDir.y);
var ustraight1 = ucenter + offset*side;
var ustraight2 = ucenter - offset*side;
if (ustraight1 >= 0 && ustraight1 <= capsuleLength) {
var p = capsuleStart + capsuleDir * ustraight1 - normal * radius;
var tstraight1 = math.dot(p - lineStart, lineDir);
tmin = math.min(tmin, tstraight1);
tmax = math.max(tmax, tstraight1);
}
if (ustraight2 >= 0 && ustraight2 <= capsuleLength) {
var p = capsuleStart + capsuleDir * ustraight2 + normal * radius;
var tstraight2 = math.dot(p - lineStart, lineDir);
tmin = math.min(tmin, tstraight2);
tmax = math.max(tmax, tstraight2);
}
} else {
// Parallel, or almost parallel.
// In this case we can just rely on the circle intersection checks.
}
return new float2(tmin, tmax);
}
///
/// Calculates the point start1 + dir1*t where the two infinite lines intersect.
/// Returns false if the lines are close to parallel.
///
public static bool LineLineIntersectionFactor (float2 start1, float2 dir1, float2 start2, float2 dir2, out float t) {
float den = dir2.y*dir1.x - dir2.x * dir1.y;
if (math.abs(den) < 0.0001f) {
t = 0;
return false;
}
float nom = dir2.x*(start1.y-start2.y) - dir2.y*(start1.x-start2.x);
t = nom/den;
return true;
}
///
/// Calculates the point start1 + dir1*factor1 == start2 + dir2*factor2 where the two infinite lines intersect.
/// Returns false if the lines are close to parallel.
///
public static bool LineLineIntersectionFactors (float2 start1, float2 dir1, float2 start2, float2 dir2, out float factor1, out float factor2) {
float den = dir2.y*dir1.x - dir2.x * dir1.y;
if (math.abs(den) < 0.0001f) {
factor1 = factor2 = 0;
return false;
}
float nom1 = dir2.x*(start1.y-start2.y) - dir2.y*(start1.x-start2.x);
float nom2 = dir1.x*(start1.y-start2.y) - dir1.y*(start1.x - start2.x);
factor1 = nom1/den;
factor2 = nom2/den;
return true;
}
///
/// Intersection point between two infinite lines.
/// Note that start points and directions are taken as parameters instead of start and end points.
/// Lines are treated as infinite. If the lines are parallel 'start1' will be returned.
/// Intersections are calculated on the XZ plane.
///
/// See: LineIntersectionPointXZ
///
public static Vector3 LineDirIntersectionPointXZ (Vector3 start1, Vector3 dir1, Vector3 start2, Vector3 dir2) {
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
return start1;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float u = nom/den;
return start1 + dir1*u;
}
///
/// Intersection point between two infinite lines.
/// Note that start points and directions are taken as parameters instead of start and end points.
/// Lines are treated as infinite. If the lines are parallel 'start1' will be returned.
/// Intersections are calculated on the XZ plane.
///
/// See: LineIntersectionPointXZ
///
public static Vector3 LineDirIntersectionPointXZ (Vector3 start1, Vector3 dir1, Vector3 start2, Vector3 dir2, out bool intersects) {
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
intersects = false;
return start1;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float u = nom/den;
intersects = true;
return start1 + dir1*u;
}
///
/// Returns if the ray (start1, end1) intersects the segment (start2, end2).
/// false is returned if the lines are parallel.
/// Only the XZ coordinates are used.
/// TODO: Double check that this actually works
///
public static bool RaySegmentIntersectXZ (Int3 start1, Int3 end1, Int3 start2, Int3 end2) {
Int3 dir1 = end1-start1;
Int3 dir2 = end2-start2;
long den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
return false;
}
long nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
long nom2 = dir1.x*(start1.z-start2.z) - dir1.z * (start1.x - start2.x);
//factor1 < 0
// If both have the same sign, then nom/den < 0 and thus the segment cuts the ray before the ray starts
if (!(nom < 0 ^ den < 0)) {
return false;
}
//factor2 < 0
if (!(nom2 < 0 ^ den < 0)) {
return false;
}
if ((den >= 0 && nom2 > den) || (den < 0 && nom2 <= den)) {
return false;
}
return true;
}
///
/// Returns the intersection factors for line 1 and line 2. The intersection factors is a distance along the line start - end where the other line intersects it.
/// intersectionPoint = start1 + factor1 * (end1-start1)
/// intersectionPoint2 = start2 + factor2 * (end2-start2)
/// Lines are treated as infinite.
/// false is returned if the lines are parallel and true if they are not.
/// Only the XZ coordinates are used.
///
public static bool LineIntersectionFactorXZ (Int3 start1, Int3 end1, Int3 start2, Int3 end2, out float factor1, out float factor2) {
Int3 dir1 = end1-start1;
Int3 dir2 = end2-start2;
long den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
factor1 = 0;
factor2 = 0;
return false;
}
long nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
long nom2 = dir1.x*(start1.z-start2.z) - dir1.z * (start1.x - start2.x);
factor1 = (float)nom/den;
factor2 = (float)nom2/den;
return true;
}
///
/// Returns the intersection factors for line 1 and line 2. The intersection factors is a distance along the line start - end where the other line intersects it.
/// intersectionPoint = start1 + factor1 * (end1-start1)
/// intersectionPoint2 = start2 + factor2 * (end2-start2)
/// Lines are treated as infinite.
/// false is returned if the lines are parallel and true if they are not.
/// Only the XZ coordinates are used.
///
public static bool LineIntersectionFactorXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2, out float factor1, out float factor2) {
Vector3 dir1 = end1-start1;
Vector3 dir2 = end2-start2;
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den <= 0.00001f && den >= -0.00001f) {
factor1 = 0;
factor2 = 0;
return false;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float nom2 = dir1.x*(start1.z-start2.z) - dir1.z * (start1.x - start2.x);
float u = nom/den;
float u2 = nom2/den;
factor1 = u;
factor2 = u2;
return true;
}
///
/// Returns the intersection factor for line 1 with ray 2.
/// The intersection factors is a factor distance along the line start - end where the other line intersects it.
/// intersectionPoint = start1 + factor * (end1-start1)
/// Lines are treated as infinite.
///
/// The second "line" is treated as a ray, meaning only matches on start2 or forwards towards end2 (and beyond) will be returned
/// If the point lies on the wrong side of the ray start, Nan will be returned.
///
/// NaN is returned if the lines are parallel.
///
public static float LineRayIntersectionFactorXZ (Int3 start1, Int3 end1, Int3 start2, Int3 end2) {
Int3 dir1 = end1-start1;
Int3 dir2 = end2-start2;
int den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
return float.NaN;
}
int nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
int nom2 = dir1.x*(start1.z-start2.z) - dir1.z * (start1.x - start2.x);
if ((float)nom2/den < 0) {
return float.NaN;
}
return (float)nom/den;
}
///
/// Returns the intersection factor for line 1 with line 2.
/// The intersection factor is a distance along the line start1 - end1 where the line start2 - end2 intersects it.
/// intersectionPoint = start1 + intersectionFactor * (end1-start1)
.
/// Lines are treated as infinite.
/// -1 is returned if the lines are parallel (note that this is a valid return value if they are not parallel too)
///
public static float LineIntersectionFactorXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2) {
Vector3 dir1 = end1-start1;
Vector3 dir2 = end2-start2;
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
return -1;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float u = nom/den;
return u;
}
/// Returns the intersection point between the two lines. Lines are treated as infinite. start1 is returned if the lines are parallel
public static Vector3 LineIntersectionPointXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2) {
bool s;
return LineIntersectionPointXZ(start1, end1, start2, end2, out s);
}
/// Returns the intersection point between the two lines. Lines are treated as infinite. start1 is returned if the lines are parallel
public static Vector3 LineIntersectionPointXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2, out bool intersects) {
Vector3 dir1 = end1-start1;
Vector3 dir2 = end2-start2;
float den = dir2.z*dir1.x - dir2.x * dir1.z;
if (den == 0) {
intersects = false;
return start1;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float u = nom/den;
intersects = true;
return start1 + dir1*u;
}
/// Returns the intersection point between the two lines. Lines are treated as infinite. start1 is returned if the lines are parallel
public static Vector2 LineIntersectionPoint (Vector2 start1, Vector2 end1, Vector2 start2, Vector2 end2) {
bool s;
return LineIntersectionPoint(start1, end1, start2, end2, out s);
}
/// Returns the intersection point between the two lines. Lines are treated as infinite. start1 is returned if the lines are parallel
public static Vector2 LineIntersectionPoint (Vector2 start1, Vector2 end1, Vector2 start2, Vector2 end2, out bool intersects) {
Vector2 dir1 = end1-start1;
Vector2 dir2 = end2-start2;
float den = dir2.y*dir1.x - dir2.x * dir1.y;
if (den == 0) {
intersects = false;
return start1;
}
float nom = dir2.x*(start1.y-start2.y)- dir2.y*(start1.x-start2.x);
float u = nom/den;
intersects = true;
return start1 + dir1*u;
}
///
/// Returns the intersection point between the two line segments in XZ space.
/// Lines are NOT treated as infinite. start1 is returned if the line segments do not intersect
/// The point will be returned along the line [start1, end1] (this matters only for the y coordinate).
///
public static Vector3 SegmentIntersectionPointXZ (Vector3 start1, Vector3 end1, Vector3 start2, Vector3 end2, out bool intersects) {
Vector3 dir1 = end1-start1;
Vector3 dir2 = end2-start2;
float den = dir2.z * dir1.x - dir2.x * dir1.z;
if (den == 0) {
intersects = false;
return start1;
}
float nom = dir2.x*(start1.z-start2.z)- dir2.z*(start1.x-start2.x);
float nom2 = dir1.x*(start1.z-start2.z) - dir1.z*(start1.x-start2.x);
float u = nom/den;
float u2 = nom2/den;
if (u < 0F || u > 1F || u2 < 0F || u2 > 1F) {
intersects = false;
return start1;
}
intersects = true;
return start1 + dir1*u;
}
///
/// Does the line segment intersect the bounding box.
/// The line is NOT treated as infinite.
/// \author Slightly modified code from http://www.3dkingdoms.com/weekly/weekly.php?a=21
///
public static bool SegmentIntersectsBounds (Bounds bounds, Vector3 a, Vector3 b) {
// Put segment in box space
a -= bounds.center;
b -= bounds.center;
// Get line midpoint and extent
var LMid = (a + b) * 0.5F;
var L = (a - LMid);
var LExt = new Vector3(Math.Abs(L.x), Math.Abs(L.y), Math.Abs(L.z));
Vector3 extent = bounds.extents;
// Use Separating Axis Test
// Separation vector from box center to segment center is LMid, since the line is in box space
if (Math.Abs(LMid.x) > extent.x + LExt.x) return false;
if (Math.Abs(LMid.y) > extent.y + LExt.y) return false;
if (Math.Abs(LMid.z) > extent.z + LExt.z) return false;
// Crossproducts of line and each axis
if (Math.Abs(LMid.y * L.z - LMid.z * L.y) > (extent.y * LExt.z + extent.z * LExt.y)) return false;
if (Math.Abs(LMid.x * L.z - LMid.z * L.x) > (extent.x * LExt.z + extent.z * LExt.x)) return false;
if (Math.Abs(LMid.x * L.y - LMid.y * L.x) > (extent.x * LExt.y + extent.y * LExt.x)) return false;
// No separating axis, the line intersects
return true;
}
///
/// Calculates the two intersection points (point + direction*t) on the line where it intersects with a circle at the origin.
///
/// t1 will always be less than or equal to t2 if there are intersections.
///
/// Returns false if there are no intersections.
///
/// A point on the line
/// The normalized direction of the line
/// The radius of the circle at the origin.
/// The first intersection (if any).
/// The second intersection (if any).
public static bool LineCircleIntersectionFactors (float2 point, float2 direction, float radius, out float t1, out float t2) {
// Distance from the closest point on the line (from the origin) to line.point
float dot = math.dot(point, direction);
// Squared distance from the origin to the closest point on the line
float distanceToLine = math.lengthsq(point) - dot*dot;
// Calculate the intersection of the line with the circle.
// This is the squared length of half the chord that intersects the circle.
float discriminant = radius*radius - distanceToLine;
if (discriminant < 0.0f) {
// The line is completely outside the circle
t1 = float.PositiveInfinity;
t2 = float.NegativeInfinity;
return false;
}
var sqrtDiscriminant = math.sqrt(discriminant);
t1 = -dot - sqrtDiscriminant;
t2 = -dot + sqrtDiscriminant;
return true;
}
///
/// Calculates the two intersection points (lerp(point1, point2, t)) on the segment where it intersects with a circle at the origin.
///
/// t1 will always be less than or equal to t2 if there are intersections.
///
/// Returns false if there are no intersections.
///
/// Start of the segment
/// End of the segment
/// The squared radius of the circle at the origin.
/// The first intersection (if any). Between 0 and 1.
/// The second intersection (if any). Between 0 and 1.
public static bool SegmentCircleIntersectionFactors (float2 point1, float2 point2, float radiusSq, out float t1, out float t2) {
// Distance from the closest point on the line (from the origin) to line.point
var dir = point2 - point1;
var dirSq = math.lengthsq(dir);
float dot = math.dot(point1, dir) / dirSq;
// Proportional to the squared distance from the origin to the closest point on the line
float distanceToLine = math.lengthsq(point1) / dirSq - dot*dot;
float discriminant = radiusSq/dirSq - distanceToLine;
if (discriminant < 0.0f) {
// The line is completely outside the circle
t1 = float.PositiveInfinity;
t2 = float.NegativeInfinity;
return false;
}
var sqrtDiscriminant = math.sqrt(discriminant);
t1 = -dot - sqrtDiscriminant;
t2 = -dot + sqrtDiscriminant;
t1 = math.max(0, t1);
t2 = math.min(1, t2);
if (t1 >= 1 || t2 <= 0) return false;
return true;
}
///
/// Intersection of a line and a circle.
/// Returns the greatest t such that segmentStart+t*(segmentEnd-segmentStart) lies on the circle.
///
/// In case the line does not intersect with the circle, the closest point on the line
/// to the circle will be returned.
///
/// Note: Works for line and sphere in 3D space as well.
///
/// See: http://mathworld.wolfram.com/Circle-LineIntersection.html
/// See: https://en.wikipedia.org/wiki/Intersection_(Euclidean_geometry)
///
public static float LineCircleIntersectionFactor (Vector3 circleCenter, Vector3 linePoint1, Vector3 linePoint2, float radius) {
float segmentLength;
var normalizedDirection = Normalize(linePoint2 - linePoint1, out segmentLength);
var dirToStart = linePoint1 - circleCenter;
var dot = Vector3.Dot(dirToStart, normalizedDirection);
var discriminant = dot * dot - (dirToStart.sqrMagnitude - radius*radius);
if (discriminant < 0) {
// No intersection, pick closest point on segment
discriminant = 0;
}
var t = -dot + Mathf.Sqrt(discriminant);
// Note: the default value of 1 is important for the PathInterpolator.MoveToCircleIntersection2D
// method to work properly. Maybe find some better abstraction where this default value is more obvious.
return segmentLength > 0.00001f ? t / segmentLength : 1f;
}
///
/// True if the matrix will reverse orientations of faces.
///
/// Scaling by a negative value along an odd number of axes will reverse
/// the orientation of e.g faces on a mesh. This must be counter adjusted
/// by for example the recast rasterization system to be able to handle
/// meshes with negative scales properly.
///
/// We can find out if they are flipped by finding out how the signed
/// volume of a unit cube is transformed when applying the matrix
///
/// If the (signed) volume turns out to be negative
/// that also means that the orientation of it has been reversed.
///
/// See: https://en.wikipedia.org/wiki/Normal_(geometry)
/// See: https://en.wikipedia.org/wiki/Parallelepiped
///
public static bool ReversesFaceOrientations (Matrix4x4 matrix) {
var dX = matrix.MultiplyVector(new Vector3(1, 0, 0));
var dY = matrix.MultiplyVector(new Vector3(0, 1, 0));
var dZ = matrix.MultiplyVector(new Vector3(0, 0, 1));
// Calculate the signed volume of the parallelepiped
var volume = Vector3.Dot(Vector3.Cross(dX, dY), dZ);
return volume < 0;
}
///
/// Normalize vector and also return the magnitude.
/// This is more efficient than calculating the magnitude and normalizing separately
///
public static Vector3 Normalize (Vector3 v, out float magnitude) {
magnitude = v.magnitude;
// This is the same constant that Unity uses
if (magnitude > 1E-05f) {
return v / magnitude;
} else {
return Vector3.zero;
}
}
///
/// Normalize vector and also return the magnitude.
/// This is more efficient than calculating the magnitude and normalizing separately
///
public static Vector2 Normalize (Vector2 v, out float magnitude) {
magnitude = v.magnitude;
// This is the same constant that Unity uses
if (magnitude > 1E-05f) {
return v / magnitude;
} else {
return Vector2.zero;
}
}
/* Clamp magnitude along the X and Z axes.
* The y component will not be changed.
*/
public static Vector3 ClampMagnitudeXZ (Vector3 v, float maxMagnitude) {
float squaredMagnitudeXZ = v.x*v.x + v.z*v.z;
if (squaredMagnitudeXZ > maxMagnitude*maxMagnitude && maxMagnitude > 0) {
var factor = maxMagnitude / Mathf.Sqrt(squaredMagnitudeXZ);
v.x *= factor;
v.z *= factor;
}
return v;
}
/* Magnitude in the XZ plane */
public static float MagnitudeXZ (Vector3 v) {
return Mathf.Sqrt(v.x*v.x + v.z*v.z);
}
///
/// Number of radians that this quaternion rotates around its axis of rotation.
/// Will be in the range [-PI, PI].
///
/// Note: A quaternion of q and -q represent the same rotation, but their axis of rotation point in opposite directions, so the angle will be different.
///
public static float QuaternionAngle (quaternion rot) {
return 2 * math.atan2(math.length(rot.value.xyz), rot.value.w);
}
}
///
/// Utility functions for working with numbers and strings.
///
/// See: Polygon
/// See: VectorMath
///
public static class AstarMath {
static Unity.Mathematics.Random GlobalRandom = Unity.Mathematics.Random.CreateFromIndex(0);
static object GlobalRandomLock = new object();
public static float ThreadSafeRandomFloat () {
lock (GlobalRandomLock) {
return GlobalRandom.NextFloat();
}
}
public static float2 ThreadSafeRandomFloat2 () {
lock (GlobalRandomLock) {
return GlobalRandom.NextFloat2();
}
}
/// Converts a non-negative float to a long, saturating at long.MaxValue if the value is too large
public static long SaturatingConvertFloatToLong(float v) => v > (float)long.MaxValue ? long.MaxValue : (long)v;
/// Maps a value between startMin and startMax to be between targetMin and targetMax
public static float MapTo (float startMin, float startMax, float targetMin, float targetMax, float value) {
return Mathf.Lerp(targetMin, targetMax, Mathf.InverseLerp(startMin, startMax, value));
}
///
/// Returns bit number b from int a. The bit number is zero based. Relevant b values are from 0 to 31.
/// Equals to (a >> b) & 1
///
static int Bit (int a, int b) {
return (a >> b) & 1;
}
///
/// Returns a nice color from int i with alpha a. Got code from the open-source Recast project, works really well.
/// Seems like there are only 64 possible colors from studying the code
///
public static Color IntToColor (int i, float a) {
int r = Bit(i, 2) + Bit(i, 3) * 2 + 1;
int g = Bit(i, 1) + Bit(i, 4) * 2 + 1;
int b = Bit(i, 0) + Bit(i, 5) * 2 + 1;
return new Color(r*0.25F, g*0.25F, b*0.25F, a);
}
///
/// Converts an HSV color to an RGB color.
/// According to the algorithm described at http://en.wikipedia.org/wiki/HSL_and_HSV
///
/// @author Wikipedia
/// @return the RGB representation of the color.
///
public static Color HSVToRGB (float h, float s, float v) {
float r = 0, g = 0, b = 0;
float Chroma = s * v;
float Hdash = h / 60.0f;
float X = Chroma * (1.0f - System.Math.Abs((Hdash % 2.0f) - 1.0f));
if (Hdash < 1.0f) {
r = Chroma;
g = X;
} else if (Hdash < 2.0f) {
r = X;
g = Chroma;
} else if (Hdash < 3.0f) {
g = Chroma;
b = X;
} else if (Hdash < 4.0f) {
g = X;
b = Chroma;
} else if (Hdash < 5.0f) {
r = X;
b = Chroma;
} else if (Hdash < 6.0f) {
r = Chroma;
b = X;
}
float Min = v - Chroma;
r += Min;
g += Min;
b += Min;
return new Color(r, g, b);
}
///
/// Calculates the shortest difference between two given angles given in radians.
///
/// The return value will be between -pi/2 and +pi/2.
///
public static float DeltaAngle (float angle1, float angle2) {
float diff = (angle2 - angle1 + math.PI) % (2*math.PI) - math.PI;
return math.select(diff, diff + 2*math.PI, diff < -math.PI);
}
}
///
/// Utility functions for working with polygons, lines, and other vector math.
/// All functions which accepts Vector3s but work in 2D space uses the XZ space if nothing else is said.
///
/// Version: A lot of functions in this class have been moved to the VectorMath class
/// the names have changed slightly and everything now consistently assumes a left handed
/// coordinate system now instead of sometimes using a left handed one and sometimes
/// using a right handed one. This is why the 'Left' methods redirect to methods
/// named 'Right'. The functionality is exactly the same.
///
[BurstCompile]
public static class Polygon {
///
/// Returns if the triangle ABC contains the point p in XZ space.
/// The triangle vertices are assumed to be laid out in clockwise order.
///
public static bool ContainsPointXZ (Vector3 a, Vector3 b, Vector3 c, Vector3 p) {
return VectorMath.IsClockwiseMarginXZ(a, b, p) && VectorMath.IsClockwiseMarginXZ(b, c, p) && VectorMath.IsClockwiseMarginXZ(c, a, p);
}
///
/// Returns if the triangle ABC contains the point p.
/// The triangle vertices are assumed to be laid out in clockwise order.
///
public static bool ContainsPointXZ (Int3 a, Int3 b, Int3 c, Int3 p) {
return VectorMath.IsClockwiseOrColinearXZ(a, b, p) && VectorMath.IsClockwiseOrColinearXZ(b, c, p) && VectorMath.IsClockwiseOrColinearXZ(c, a, p);
}
///
/// Returns if the triangle ABC contains the point p.
/// The triangle vertices are assumed to be laid out in clockwise order.
///
public static bool ContainsPoint (Int2 a, Int2 b, Int2 c, Int2 p) {
return VectorMath.IsClockwiseOrColinear(a, b, p) && VectorMath.IsClockwiseOrColinear(b, c, p) && VectorMath.IsClockwiseOrColinear(c, a, p);
}
///
/// Checks if p is inside the polygon.
/// \author http://unifycommunity.com/wiki/index.php?title=PolyContainsPoint (Eric5h5)
///
public static bool ContainsPoint (Vector2[] polyPoints, Vector2 p) {
int j = polyPoints.Length-1;
bool inside = false;
for (int i = 0; i < polyPoints.Length; j = i++) {
if (((polyPoints[i].y <= p.y && p.y < polyPoints[j].y) || (polyPoints[j].y <= p.y && p.y < polyPoints[i].y)) &&
(p.x < (polyPoints[j].x - polyPoints[i].x) * (p.y - polyPoints[i].y) / (polyPoints[j].y - polyPoints[i].y) + polyPoints[i].x))
inside = !inside;
}
return inside;
}
///
/// Checks if p is inside the polygon (XZ space).
/// \author http://unifycommunity.com/wiki/index.php?title=PolyContainsPoint (Eric5h5)
///
public static bool ContainsPointXZ (Vector3[] polyPoints, Vector3 p) {
int j = polyPoints.Length-1;
bool inside = false;
for (int i = 0; i < polyPoints.Length; j = i++) {
if (((polyPoints[i].z <= p.z && p.z < polyPoints[j].z) || (polyPoints[j].z <= p.z && p.z < polyPoints[i].z)) &&
(p.x < (polyPoints[j].x - polyPoints[i].x) * (p.z - polyPoints[i].z) / (polyPoints[j].z - polyPoints[i].z) + polyPoints[i].x))
inside = !inside;
}
return inside;
}
///
/// Returns if the triangle contains the point p when projected on the movement plane.
/// The triangle vertices may be clockwise or counter-clockwise.
///
/// This method is numerically robust, as in, if the point is contained in exactly one of two adjacent triangles, then this
/// function will return true for at least one of them (both if the point is exactly on the edge between them).
/// If it was less numerically robust, it could conceivably return false for both of them if the point was on the edge between them, which would be bad.
///
[BurstCompile]
public static bool ContainsPoint (ref int3 aWorld, ref int3 bWorld, ref int3 cWorld, ref int3 pWorld, ref NativeMovementPlane movementPlane) {
// Extract the coordinate axes of the movement plane
var m = new float3x3(movementPlane.rotation.value);
var m2D = math.transpose(new float3x2(m.c0, m.c2));
return ContainsPoint(ref aWorld, ref bWorld, ref cWorld, ref pWorld, in m2D);
}
///
/// Returns if the triangle contains the point p when projected on a plane using the given projection.
/// The triangle vertices may be clockwise or counter-clockwise.
///
/// This method is numerically robust, as in, if the point is contained in exactly one of two adjacent triangles, then this
/// function will return true for at least one of them (both if the point is exactly on the edge between them).
/// If it was less numerically robust, it could conceivably return false for both of them if the point was on the edge between them, which would be bad.
///
public static bool ContainsPoint (ref int3 aWorld, ref int3 bWorld, ref int3 cWorld, ref int3 pWorld, in float2x3 planeProjection) {
const int QUANTIZATION = 1024;
var m = new int2x3(planeProjection * QUANTIZATION);
// Project all the points onto the movement plane using SIMD
var xs = new int4(aWorld.x, bWorld.x, cWorld.x, pWorld.x);
var ys = new int4(aWorld.y, bWorld.y, cWorld.y, pWorld.y);
var zs = new int4(aWorld.z, bWorld.z, cWorld.z, pWorld.z);
// Subtract the first point from all the other points
// This ensures that large coordinates will not overflow due to using 32 bits here.
// Since we multiply all coordinates by QUANTIZATION, and Int3 coordinates are already multiplied by 1000,
// coordinates would otherwise be liable to start overflowing at unity world coordinates above around 2000.
// TODO: We could still get bad results if pWorld is very far away from the triangle (about 4000 units).
xs -= xs.x;
ys -= ys.x;
zs -= zs.x;
// Projected X and Y coordinates
var px = (xs * m.c0.x + ys * m.c1.x + zs * m.c2.x) / QUANTIZATION;
var py = (xs * m.c0.y + ys * m.c1.y + zs * m.c2.y) / QUANTIZATION;
// Do 3 cross products to check if the point is inside the triangle
var v1 = px.yzx - px.xyz;
var v2 = py.www - py.xyz;
var v3 = px.www - px.xyz;
var v4 = py.yzx - py.xyz;
long check1 = (long)v1.x * (long)v2.x - (long)v3.x * (long)v4.x;
long check2 = (long)v1.y * (long)v2.y - (long)v3.y * (long)v4.y;
long check3 = (long)v1.z * (long)v2.z - (long)v3.z * (long)v4.z;
// Allow for both clockwise and counter-clockwise triangle layouts.
// This can be important sometimes on spherical worlds where the "upside-down" triangles
// will be seen as having the reverse winding order when projected onto a plane.
// We take care to include points right on the edge of the triangle.
return (check1 >= 0 & check2 >= 0 & check3 >= 0) | (check1 <= 0 & check2 <= 0 & check3 <= 0);
// Note: It might be tempting to try to use SIMD-like code for this. But the following requires a lot more instructions, as it turns out.
// return math.all(new bool3(check1 >= 0, check2 >= 0, check3 >= 0)) || math.all(new bool3(check1 <= 0, check2 <= 0, check3 <= 0));
}
///
/// Sample Y coordinate of the triangle (p1, p2, p3) at the point p in XZ space.
/// The y coordinate of p is ignored.
///
/// Returns: The interpolated y coordinate unless the triangle is degenerate in which case a DivisionByZeroException will be thrown
///
/// See: https://en.wikipedia.org/wiki/Barycentric_coordinate_system
///
public static int SampleYCoordinateInTriangle (Int3 p1, Int3 p2, Int3 p3, Int3 p) {
double det = ((double)(p2.z - p3.z)) * (p1.x - p3.x) + ((double)(p3.x - p2.x)) * (p1.z - p3.z);
double lambda1 = ((((double)(p2.z - p3.z)) * (p.x - p3.x) + ((double)(p3.x - p2.x)) * (p.z - p3.z)) / det);
double lambda2 = ((((double)(p3.z - p1.z)) * (p.x - p3.x) + ((double)(p1.x - p3.x)) * (p.z - p3.z)) / det);
return (int)Math.Round(lambda1 * p1.y + lambda2 * p2.y + (1 - lambda1 - lambda2) * p3.y);
}
///
/// Calculates convex hull in XZ space for the points.
/// Implemented using the very simple Gift Wrapping Algorithm
/// which has a complexity of O(nh) where n is the number of points and h is the number of points on the hull,
/// so it is in the worst case quadratic.
///
public static Vector3[] ConvexHullXZ (Vector3[] points) {
if (points.Length == 0) return new Vector3[0];
var hull = Pathfinding.Util.ListPool.Claim();
int pointOnHull = 0;
for (int i = 1; i < points.Length; i++) if (points[i].x < points[pointOnHull].x) pointOnHull = i;
int startpoint = pointOnHull;
int counter = 0;
do {
hull.Add(points[pointOnHull]);
int endpoint = 0;
for (int i = 0; i < points.Length; i++) if (endpoint == pointOnHull || !VectorMath.RightOrColinearXZ(points[pointOnHull], points[endpoint], points[i])) endpoint = i;
pointOnHull = endpoint;
counter++;
if (counter > 10000) {
Debug.LogWarning("Infinite Loop in Convex Hull Calculation");
break;
}
} while (pointOnHull != startpoint);
var result = hull.ToArray();
// Return to pool
Pathfinding.Util.ListPool.Release(hull);
return result;
}
///
/// Closest point on the triangle abc to the point p.
/// See: 'Real Time Collision Detection' by Christer Ericson, chapter 5.1, page 141
///
public static Vector2 ClosestPointOnTriangle (Vector2 a, Vector2 b, Vector2 c, Vector2 p) {
// Check if p is in vertex region outside A
var ab = b - a;
var ac = c - a;
var ap = p - a;
var d1 = Vector2.Dot(ab, ap);
var d2 = Vector2.Dot(ac, ap);
// Barycentric coordinates (1,0,0)
if (d1 <= 0 && d2 <= 0) {
return a;
}
// Check if p is in vertex region outside B
var bp = p - b;
var d3 = Vector2.Dot(ab, bp);
var d4 = Vector2.Dot(ac, bp);
// Barycentric coordinates (0,1,0)
if (d3 >= 0 && d4 <= d3) {
return b;
}
// Check if p is in edge region outside AB, if so return a projection of p onto AB
if (d1 >= 0 && d3 <= 0) {
var vc = d1 * d4 - d3 * d2;
if (vc <= 0) {
// Barycentric coordinates (1-v, v, 0)
var v = d1 / (d1 - d3);
return a + ab*v;
}
}
// Check if p is in vertex region outside C
var cp = p - c;
var d5 = Vector2.Dot(ab, cp);
var d6 = Vector2.Dot(ac, cp);
// Barycentric coordinates (0,0,1)
if (d6 >= 0 && d5 <= d6) {
return c;
}
// Check if p is in edge region of AC, if so return a projection of p onto AC
if (d2 >= 0 && d6 <= 0) {
var vb = d5 * d2 - d1 * d6;
if (vb <= 0) {
// Barycentric coordinates (1-v, 0, v)
var v = d2 / (d2 - d6);
return a + ac*v;
}
}
// Check if p is in edge region of BC, if so return projection of p onto BC
if ((d4 - d3) >= 0 && (d5 - d6) >= 0) {
var va = d3 * d6 - d5 * d4;
if (va <= 0) {
var v = (d4 - d3) / ((d4 - d3) + (d5 - d6));
return b + (c - b) * v;
}
}
return p;
}
///
/// Closest point on the triangle abc to the point p when seen from above.
/// See: 'Real Time Collision Detection' by Christer Ericson, chapter 5.1, page 141
///
public static Vector3 ClosestPointOnTriangleXZ (Vector3 a, Vector3 b, Vector3 c, Vector3 p) {
// Check if p is in vertex region outside A
var ab = new Vector2(b.x - a.x, b.z - a.z);
var ac = new Vector2(c.x - a.x, c.z - a.z);
var ap = new Vector2(p.x - a.x, p.z - a.z);
var d1 = Vector2.Dot(ab, ap);
var d2 = Vector2.Dot(ac, ap);
// Barycentric coordinates (1,0,0)
if (d1 <= 0 && d2 <= 0) {
return a;
}
// Check if p is in vertex region outside B
var bp = new Vector2(p.x - b.x, p.z - b.z);
var d3 = Vector2.Dot(ab, bp);
var d4 = Vector2.Dot(ac, bp);
// Barycentric coordinates (0,1,0)
if (d3 >= 0 && d4 <= d3) {
return b;
}
// Check if p is in edge region outside AB, if so return a projection of p onto AB
var vc = d1 * d4 - d3 * d2;
if (d1 >= 0 && d3 <= 0 && vc <= 0) {
// Barycentric coordinates (1-v, v, 0)
var v = d1 / (d1 - d3);
return (1-v)*a + v*b;
}
// Check if p is in vertex region outside C
var cp = new Vector2(p.x - c.x, p.z - c.z);
var d5 = Vector2.Dot(ab, cp);
var d6 = Vector2.Dot(ac, cp);
// Barycentric coordinates (0,0,1)
if (d6 >= 0 && d5 <= d6) {
return c;
}
// Check if p is in edge region of AC, if so return a projection of p onto AC
var vb = d5 * d2 - d1 * d6;
if (d2 >= 0 && d6 <= 0 && vb <= 0) {
// Barycentric coordinates (1-v, 0, v)
var v = d2 / (d2 - d6);
return (1-v)*a + v*c;
}
// Check if p is in edge region of BC, if so return projection of p onto BC
var va = d3 * d6 - d5 * d4;
if ((d4 - d3) >= 0 && (d5 - d6) >= 0 && va <= 0) {
var v = (d4 - d3) / ((d4 - d3) + (d5 - d6));
return b + (c - b) * v;
} else {
// P is inside the face region. Compute the point using its barycentric coordinates (u, v, w)
// Note that the x and z coordinates will be exactly the same as P's x and z coordinates
var denom = 1f / (va + vb + vc);
var v = vb * denom;
var w = vc * denom;
return new Vector3(p.x, (1 - v - w)*a.y + v*b.y + w*c.y, p.z);
}
}
///
/// Closest point on the triangle abc to the point p.
/// See: 'Real Time Collision Detection' by Christer Ericson, chapter 5.1, page 141
///
public static float3 ClosestPointOnTriangle (float3 a, float3 b, float3 c, float3 p) {
ClosestPointOnTriangleByRef(in a, in b, in c, in p, out var output);
return output;
}
///
/// Closest point on the triangle abc to the point p.
///
/// Takes arguments by reference to be able to be burst-compiled.
///
/// See: 'Real Time Collision Detection' by Christer Ericson, chapter 5.1, page 141
///
/// Returns: True if the point is inside the triangle, false otherwise, after the point has been projected on the plane that the triangle is in.
///
[BurstCompile]
public static bool ClosestPointOnTriangleByRef (in float3 a, in float3 b, in float3 c, in float3 p, [NoAlias] out float3 output) {
// Check if p is in vertex region outside A
var ab = b - a;
var ac = c - a;
var ap = p - a;
var d1 = math.dot(ab, ap);
var d2 = math.dot(ac, ap);
// Barycentric coordinates (1,0,0)
if (d1 <= 0 && d2 <= 0) {
output = a;
return false;
}
// Check if p is in vertex region outside B
var bp = p - b;
var d3 = math.dot(ab, bp);
var d4 = math.dot(ac, bp);
// Barycentric coordinates (0,1,0)
if (d3 >= 0 && d4 <= d3) {
output = b;
return false;
}
// Check if p is in edge region outside AB, if so return a projection of p onto AB
var vc = d1 * d4 - d3 * d2;
if (d1 >= 0 && d3 <= 0 && vc <= 0) {
// Barycentric coordinates (1-v, v, 0)
var v = d1 / (d1 - d3);
output = a + ab * v;
return false;
}
// Check if p is in vertex region outside C
var cp = p - c;
var d5 = math.dot(ab, cp);
var d6 = math.dot(ac, cp);
// Barycentric coordinates (0,0,1)
if (d6 >= 0 && d5 <= d6) {
output = c;
return false;
}
// Check if p is in edge region of AC, if so return a projection of p onto AC
var vb = d5 * d2 - d1 * d6;
if (d2 >= 0 && d6 <= 0 && vb <= 0) {
// Barycentric coordinates (1-v, 0, v)
var v = d2 / (d2 - d6);
output = a + ac * v;
return false;
}
// Check if p is in edge region of BC, if so return projection of p onto BC
var va = d3 * d6 - d5 * d4;
if ((d4 - d3) >= 0 && (d5 - d6) >= 0 && va <= 0) {
var v = (d4 - d3) / ((d4 - d3) + (d5 - d6));
output = b + (c - b) * v;
return false;
} else {
// P is inside the face region. Compute the point using its barycentric coordinates (u, v, w)
var denom = 1f / (va + vb + vc);
var v = vb * denom;
var w = vc * denom;
// This is equal to: u*a + v*b + w*c, u = va*denom = 1 - v - w;
output = a + ab * v + ac * w;
return true;
}
}
///
/// Closest point on the triangle abc to the point p as barycentric coordinates.
///
/// See: 'Real Time Collision Detection' by Christer Ericson, chapter 5.1, page 141
///
public static float3 ClosestPointOnTriangleBarycentric (float2 a, float2 b, float2 c, float2 p) {
// Check if p is in vertex region outside A
var ab = b - a;
var ac = c - a;
var ap = p - a;
var d1 = math.dot(ab, ap);
var d2 = math.dot(ac, ap);
// Barycentric coordinates (1,0,0)
if (d1 <= 0 && d2 <= 0) {
return new float3(1, 0, 0);
}
// Check if p is in vertex region outside B
var bp = p - b;
var d3 = math.dot(ab, bp);
var d4 = math.dot(ac, bp);
// Barycentric coordinates (0,1,0)
if (d3 >= 0 && d4 <= d3) {
return new float3(0, 1, 0);
}
// Check if p is in edge region outside AB, if so return a projection of p onto AB
var vc = d1 * d4 - d3 * d2;
if (d1 >= 0 && d3 <= 0 && vc <= 0) {
// Barycentric coordinates (1-v, v, 0)
var v = d1 / (d1 - d3);
return new float3(1-v, v, 0);
}
// Check if p is in vertex region outside C
var cp = p - c;
var d5 = math.dot(ab, cp);
var d6 = math.dot(ac, cp);
// Barycentric coordinates (0,0,1)
if (d6 >= 0 && d5 <= d6) {
return new float3(0, 0, 1);
}
// Check if p is in edge region of AC, if so return a projection of p onto AC
var vb = d5 * d2 - d1 * d6;
if (d2 >= 0 && d6 <= 0 && vb <= 0) {
// Barycentric coordinates (1-v, 0, v)
var v = d2 / (d2 - d6);
return new float3(1 - v, 0, v);
}
// Check if p is in edge region of BC, if so return projection of p onto BC
var va = d3 * d6 - d5 * d4;
if ((d4 - d3) >= 0 && (d5 - d6) >= 0 && va <= 0) {
var v = (d4 - d3) / ((d4 - d3) + (d5 - d6));
return new float3(0, 1 - v, v);
} else {
// P is inside the face region. Compute the point using its barycentric coordinates (u, v, w)
var denom = 1f / (va + vb + vc);
var v = vb * denom;
var w = vc * denom;
return new float3(1 - v - w, v, w);
// This is equal to: u*a + v*b + w*c, u = va*denom = 1 - v - w;
// return a + ab * v + ac * w;
}
}
///
/// Closest point on a triangle when one axis is scaled.
///
/// Project the triangle onto the plane defined by the projection axis.
/// Then find the closest point on the triangle in the plane.
/// Calculate the distance to the closest point in the plane, call that D1.
/// Convert the closest point into 3D space, and calculate the distance to the
/// query point along the plane's normal, call that D2.
/// The final cost for a given point is D1 + D2 * distanceScaleAlongProjectionDirection.
///
/// This will form a diamond shape of equivalent cost points around the query point (x).
/// The ratio of the width of this diamond to the height is equal to distanceScaleAlongProjectionDirection.
///
/// ^
/// / \
/// / \
/// / x \
/// \ /
/// \ /
/// \ /
/// v
///
/// See:
///
/// First vertex of the triangle, in graph space.
/// Second vertex of the triangle, in graph space.
/// Third vertex of the triangle, in graph space.
/// Projection parameters that are for example constructed from a movement plane.
/// Point to find the closest point to.
/// Closest point on the triangle to the point.
/// Squared cost from the point to the closest point on the triangle.
/// Distance from the point to the closest point on the triangle along the projection axis.
[BurstCompile]
public static void ClosestPointOnTriangleProjected (ref Int3 vi1, ref Int3 vi2, ref Int3 vi3, ref BBTree.ProjectionParams projection, ref float3 point, [NoAlias] out float3 closest, [NoAlias] out float sqrDist, [NoAlias] out float distAlongProjection) {
var v1 = (float3)vi1;
var v2 = (float3)vi2;
var v3 = (float3)vi3;
var v1proj = math.mul(projection.planeProjection, v1);
var v2proj = math.mul(projection.planeProjection, v2);
var v3proj = math.mul(projection.planeProjection, v3);
// TODO: Can be cached
var pointProj = math.mul(projection.planeProjection, point);
var closestBarycentric = ClosestPointOnTriangleBarycentric(v1proj, v2proj, v3proj, pointProj);
closest = v1*closestBarycentric.x + v2*closestBarycentric.y + v3*closestBarycentric.z;
var closestProj = v1proj*closestBarycentric.x + v2proj*closestBarycentric.y + v3proj*closestBarycentric.z;
distAlongProjection = math.abs(math.dot(closest - point, projection.projectionAxis));
var distInPlane = math.length(closestProj - pointProj);
if (distInPlane < 0.01f) {
// If we are very close to being inside the triangle,
// check if we are actually inside the triangle using a more numerically robust method.
// If we are, set the in-plane-distance to 0.
// This is particularly important if distanceScaleAlongProjectionAxis is zero,
// as otherwise tie breaking may not work due to numerical issues.
var ci1 = (int3)vi1;
var ci2 = (int3)vi2;
var ci3 = (int3)vi3;
// wow, ugly
var pi = (int3)(Int3)(Vector3)point;
if (ContainsPoint(ref ci1, ref ci2, ref ci3, ref pi, in projection.planeProjection)) {
distInPlane = 0;
}
}
var dist = distInPlane + distAlongProjection*projection.distanceScaleAlongProjectionAxis;
sqrDist = dist*dist;
}
/// Cached dictionary to avoid excessive allocations
static readonly Dictionary cached_Int3_int_dict = new Dictionary();
///
/// Compress the mesh by removing duplicate vertices.
///
/// Vertices that differ by only 1 along the y coordinate will also be merged together.
/// Warning: This function is not threadsafe. It uses some cached structures to reduce allocations.
///
/// Vertices of the input mesh
/// Triangles of the input mesh
/// Tags of the input mesh. One for each triangle.
/// Vertices of the output mesh.
/// Triangles of the output mesh.
/// Tags of the output mesh. One for each triangle.
public static void CompressMesh (List vertices, List triangles, List tags, out Int3[] outVertices, out int[] outTriangles, out uint[] outTags) {
Dictionary firstVerts = cached_Int3_int_dict;
firstVerts.Clear();
// Use cached array to reduce memory allocations
int[] compressedPointers = ArrayPool.Claim(vertices.Count);
// Map positions to the first index they were encountered at
int count = 0;
for (int i = 0; i < vertices.Count; i++) {
// Check if the vertex position has already been added
// Also check one position up and one down because rounding errors can cause vertices
// that should end up in the same position to be offset 1 unit from each other
// TODO: Check along X and Z axes as well?
int ind;
if (!firstVerts.TryGetValue(vertices[i], out ind) && !firstVerts.TryGetValue(vertices[i] + new Int3(0, 1, 0), out ind) && !firstVerts.TryGetValue(vertices[i] + new Int3(0, -1, 0), out ind)) {
firstVerts.Add(vertices[i], count);
compressedPointers[i] = count;
vertices[count] = vertices[i];
count++;
} else {
compressedPointers[i] = ind;
}
}
// Create the triangle array or reuse the existing buffer
outTriangles = new int[triangles.Count];
// Remap the triangles to the new compressed indices
for (int i = 0; i < outTriangles.Length; i++) {
outTriangles[i] = compressedPointers[triangles[i]];
}
// Create the vertex array or reuse the existing buffer
outVertices = new Int3[count];
for (int i = 0; i < count; i++)
outVertices[i] = vertices[i];
ArrayPool.Release(ref compressedPointers);
outTags = tags.ToArray();
}
///
/// Given a set of edges between vertices, follows those edges and returns them as chains and cycles.
///
/// [Open online documentation to see images]
///
/// outline[a] = b if there is an edge from a to b.
/// hasInEdge should contain b if outline[a] = b for any key a.
/// Will be called once for each contour with the contour as a parameter as well as a boolean indicating if the contour is a cycle or a chain (see image).
public static void TraceContours (Dictionary outline, HashSet hasInEdge, System.Action, bool> results) {
// Iterate through chains of the navmesh outline.
// I.e segments of the outline that are not loops
// we need to start these at the beginning of the chain.
// Then iterate over all the loops of the outline.
// Since they are loops, we can start at any point.
var obstacleVertices = ListPool.Claim();
var outlineKeys = ListPool.Claim();
outlineKeys.AddRange(outline.Keys);
for (int k = 0; k <= 1; k++) {
bool cycles = k == 1;
for (int i = 0; i < outlineKeys.Count; i++) {
var startIndex = outlineKeys[i];
// Chains (not cycles) need to start at the start of the chain
// Cycles can start at any point
if (!cycles && hasInEdge.Contains(startIndex)) {
continue;
}
var index = startIndex;
obstacleVertices.Clear();
obstacleVertices.Add(index);
while (outline.ContainsKey(index)) {
var next = outline[index];
outline.Remove(index);
obstacleVertices.Add(next);
// We traversed a full cycle
if (next == startIndex) break;
index = next;
}
if (obstacleVertices.Count > 1) {
results(obstacleVertices, cycles);
}
}
}
ListPool.Release(ref outlineKeys);
ListPool.Release(ref obstacleVertices);
}
/// Divides each segment in the list into subSegments segments and fills the result list with the new points
public static void Subdivide (List points, List result, int subSegments) {
for (int i = 0; i < points.Count-1; i++)
for (int j = 0; j < subSegments; j++)
result.Add(Vector3.Lerp(points[i], points[i+1], j / (float)subSegments));
result.Add(points[points.Count-1]);
}
}
}