Files
j3ml/include/J3ML/Geometry.h

108 lines
3.0 KiB
C++

#include <J3ML/LinearAlgebra/Vector3.h>
#pragma once
namespace Geometry {
using Vector2 = LinearAlgebra::Vector2;
using Vector3 = LinearAlgebra::Vector3;
class LineSegment2D
{
Vector2 A;
Vector2 B;
};
class Rectangle; //AABB2D;
class OBB2D;
class Line2D;
class Ray2D;
class Triangle2D;
class Polygon2D;
struct IntersectionResult2D {
};
bool Intersects2D(LineSegment2D seg, Rectangle rect);
IntersectionResult2D GetIntersection2D(LineSegment2D seg, Rectangle rect);
// A 3D axis-aligned bounding box
// This data structure can be used to represent coarse bounds of objects, in situations where detailed triangle-level
// computations can be avoided. In physics systems, bounding boxes are used as an efficient early-out test for geometry
// intersection queries.
// the 'Axis-aligned' part in the name means that the local axes of this bounding box are restricted to align with the
// axes of the world space coordinate system. This makes computation involving AABB's very fast, since AABB's cannot
// be arbitrarily oriented in the space with respect to each other.
// If you need to represent a box in 3D space with arbitrary orientation, see the class OBB. */
class AABB;
class Capsule;
class Line;
class LineSegment
{
Vector3 A;
Vector3 B;
};
class Ray
{
Vector3 Origin;
Vector3 Direction;
};
class OBB;
class Plane
{
public:
Vector3 Position;
Vector3 Normal;
float distance = 0.f;
};
class Frustum {
public:
Plane TopFace;
Plane BottomFace;
Plane RightFace;
Plane LeftFace;
Plane FarFace;
Plane NearFace;
};
class Camera {
public:
Vector3 Position;
Vector3 Front;
Vector3 Right;
Vector3 Up;
};
static Frustum CreateFrustumFromCamera(const Camera& cam, float aspect, float fovY, float zNear, float zFar)
{
Frustum frustum;
const float halfVSide = zFar * tanf(fovY * 0.5f);
const float halfHSide = halfVSide * aspect;
const Vector3 frontMultFar = cam.Front * zFar;
frustum.NearFace = Plane{cam.Position + cam.Front * zNear, cam.Front};
frustum.FarFace = Plane{cam.Position + frontMultFar, -cam.Front};
frustum.RightFace = Plane{cam.Position, Vector3::Cross(frontMultFar - cam.Right * halfHSide, cam.Up)};
frustum.LeftFace = Plane{cam.Position, Vector3::Cross(cam.Up, frontMultFar+cam.Right*halfHSide)};
frustum.TopFace = Plane{cam.Position, Vector3::Cross(cam.Right, frontMultFar - cam.Up * halfVSide)};
frustum.BottomFace = Plane{cam.Position, Vector3::Cross(frontMultFar + cam.Up * halfVSide, cam.Right)};
return frustum;
}
class Polygon;
class Polyhedron;
class QuadTree;
class OctTree;
class Sphere;
class Triangle;
class TriangleMesh;
}