1 files changed, 95 insertions, 0 deletions
diff --git a/Runtime/Geometry/Intersection.h b/Runtime/Geometry/Intersection.h
new file mode 100644
index 0000000..4c96099
--- /dev/null
+++ b/Runtime/Geometry/Intersection.h
@@ -0,0 +1,95 @@
+#ifndef INTERSECTION_H
+#define INTERSECTION_H
+
+#include "Runtime/Math/Simd/math.h"
+
+class Ray;
+class OptimizedRay;
+class Sphere;
+class AABB;
+class Plane;
+
+class Vector3f;
+class Vector4f;
+
+// Intersects a Ray with a triangle.
+bool IntersectRayTriangle (const Ray& ray, const Vector3f& a, const Vector3f& b, const Vector3f& c);
+// t is to be non-Null and returns the first intersection point of the ray (ray.o + t * ray.dir)
+bool IntersectRayTriangle (const Ray& ray, const Vector3f& a, const Vector3f& b, const Vector3f& c, float* t);
+
+// Intersects a ray with a volume.
+// Returns true if the ray stats inside the volume or in front of the volume
+bool IntersectRaySphere (const Ray& ray, const Sphere& inSphere);
+bool IntersectRayAABB (const Ray& ray, const AABB& inAABB);
+
+// Intersects a ray with a volume.
+// Returns true if the ray stats inside the volume or in front of the volume
+// t0 is the first, t1 the second intersection. Both have to be non-NULL.
+// (t1 is always positive, t0 is negative if the ray starts inside the volume)
+bool IntersectRayAABB (const Ray& ray, const AABB& inAABB, float* t0, float* t1);
+bool IntersectRayAABB (const Ray& ray, const AABB& inAABB, float* t0);
+bool IntersectRaySphere (const Ray& ray, const Sphere& inSphere, float* t0, float* t1);
+
+// Do these volumes intersect each other?
+bool IntersectSphereSphere (const Sphere& s0, const Sphere& s1);
+bool IntersectAABBAABB (const AABB& s0, const AABB& s1);
+bool IntersectAABBSphere (const AABB& s0, const Sphere& s1);
+
+// Do these volumes intersect or touch each other?
+bool IntersectSphereSphereInclusive (const Sphere& s0, const Sphere& s1);
+bool EXPORT_COREMODULE IntersectAABBAABBInclusive (const AABB& s0, const AABB& s1);
+bool IntersectAABBSphereInclusive (const AABB& s0, const Sphere& s1);
+
+// Tests if the aabb is inside any of the planes enabled by inClipMask
+// The bitmask tells which planes have to be tested. (For 6 planes the bitmask is 63)
+bool IntersectAABBFrustum (const AABB& a, const Plane* p, UInt32 inClipMask);
+bool IntersectAABBFrustumFull (const AABB& a, const Plane p[6]);
+bool IntersectAABBPlaneBounds (const AABB& a, const Plane* p, const int planeCount);
+
+float PointDistanceToFrustum (const Vector4f& point, const Plane* p, const int planeCount);
+
+bool IntersectTriTri (const Vector3f& a0, const Vector3f& b0, const Vector3f& c0,
+					  const Vector3f& a1, const Vector3f& b1, const Vector3f& c1,
+					  Vector3f* intersectionLine0, Vector3f* intersectionLine1, bool* coplanar);
+					  
+// Intersects a ray with a plane (The ray can hit the plane from front and behind)
+// On return enter is the rays parameter where the intersection occurred.
+bool IntersectRayPlane (const Ray& ray, const Plane& plane, float* enter);
+
+
+// Intersects a line segment with a plane (can hit the plane from front and behind)
+// Fill result point if intersected.
+bool IntersectSegmentPlane( const Vector3f& p1, const Vector3f& p2, const Plane& plane, Vector3f* result );
+
+
+// Returns true if the triangle touches or is inside the triangle (a, b, c)
+bool IntersectSphereTriangle (const Sphere& s, const Vector3f& a, const Vector3f& b, const Vector3f& c);
+
+/// Returns true if the bounding box is inside the planes or intersects any of the planes.
+bool TestPlanesAABB(const Plane* planes, const int planeCount, const AABB& bounds);
+
+/// Projects point on a line.
+template <typename T>
+T ProjectPointLine(const T& point, const T& lineStart, const T& lineEnd)
+{
+	T relativePoint = point - lineStart;
+	T lineDirection = lineEnd - lineStart;
+	float length = Magnitude(lineDirection);
+	T normalizedLineDirection = lineDirection;
+	if (length > T::epsilon)
+		normalizedLineDirection /= length;
+
+	float dot = Dot(normalizedLineDirection, relativePoint);
+	dot = clamp(dot, 0.0F, length);
+
+	return lineStart + normalizedLineDirection * dot;
+}
+
+/// Returns the distance to a line from a point.
+template <typename T>
+float DistancePointLine(const T& point, const T& lineStart, const T& lineEnd)
+{
+	return Magnitude(ProjectPointLine<T>(point, lineStart, lineEnd) - point);
+}
+
+#endif