Imported more code from the old engine.

[peakengine.git] / engine / include / support / aabbox3d.h

// Copyright (C) 2002-2007 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __IRR_AABBOX_3D_H_INCLUDED__
#define __IRR_AABBOX_3D_H_INCLUDED__

#include "irrMath.h"
#include "plane3d.h"
#include "line3d.h"

namespace irr
{
namespace core
{

//! Axis aligned bounding box in 3d dimensional space.
/** Has some useful methods used with occlusion culling or clipping.
*/
template <class T>
class aabbox3d
{
        public:

                // Constructors

                aabbox3d(): MinEdge(-1,-1,-1), MaxEdge(1,1,1) {}
                aabbox3d(const vector3d<T>& min, const vector3d<T>& max): MinEdge(min), MaxEdge(max) {}
                aabbox3d(const vector3d<T>& init): MinEdge(init), MaxEdge(init) {}
                aabbox3d(T minx, T miny, T minz, T maxx, T maxy, T maxz): MinEdge(minx, miny, minz), MaxEdge(maxx, maxy, maxz) {}

                // operators

                inline bool operator==(const aabbox3d<T>& other) const { return (MinEdge == other.MinEdge && other.MaxEdge == MaxEdge);};
                inline bool operator!=(const aabbox3d<T>& other) const { return !(MinEdge == other.MinEdge && other.MaxEdge == MaxEdge);};

                // functions

                //! Adds a point to the bounding box, causing it to grow bigger, 
                //! if point is outside of the box
                //! \param p: Point to add into the box.
                void addInternalPoint(const vector3d<T>& p)
                {
                        addInternalPoint(p.X, p.Y, p.Z);
                }

                //! Adds an other bounding box to the bounding box, causing it to grow bigger,
                //! if the box is outside of the box
                //! \param b: Other bounding box to add into this box.
                void addInternalBox(const aabbox3d<T>& b)
                {
                        addInternalPoint(b.MaxEdge);
                        addInternalPoint(b.MinEdge);
                }

                //! Resets the bounding box.
                void reset(T x, T y, T z)
                {
                        MaxEdge.set(x,y,z);
                        MinEdge = MaxEdge;
                }

                //! Resets the bounding box.
                void reset(const aabbox3d<T>& initValue)
                {
                        *this = initValue;
                }

                //! Resets the bounding box.
                void reset(const vector3d<T>& initValue)
                {
                        MaxEdge = initValue;
                        MinEdge = initValue;
                }

                //! Adds a point to the bounding box, causing it to grow bigger, 
                //! if point is outside of the box.
                //! \param x: X Coordinate of the point to add to this box.
                //! \param y: Y Coordinate of the point to add to this box.
                //! \param z: Z Coordinate of the point to add to this box.
                void addInternalPoint(T x, T y, T z)
                {
                        if (x>MaxEdge.X) MaxEdge.X = x;
                        if (y>MaxEdge.Y) MaxEdge.Y = y;
                        if (z>MaxEdge.Z) MaxEdge.Z = z;

                        if (x<MinEdge.X) MinEdge.X = x;
                        if (y<MinEdge.Y) MinEdge.Y = y;
                        if (z<MinEdge.Z) MinEdge.Z = z;
                }

                //! Determinates if a point is within this box.
                //! \param p: Point to check.
                //! \return Returns true if the point is withing the box, and false if it is not.
                bool isPointInside(const vector3d<T>& p) const
                {
                        return (p.X >= MinEdge.X && p.X <= MaxEdge.X &&
                                p.Y >= MinEdge.Y && p.Y <= MaxEdge.Y &&
                                p.Z >= MinEdge.Z && p.Z <= MaxEdge.Z);
                };

                //! Determinates if a point is within this box and its borders.
                //! \param p: Point to check.
                //! \return Returns true if the point is withing the box, and false if it is not.
                bool isPointTotalInside(const vector3d<T>& p) const
                {
                        return (p.X > MinEdge.X && p.X < MaxEdge.X &&
                                p.Y > MinEdge.Y && p.Y < MaxEdge.Y &&
                                p.Z > MinEdge.Z && p.Z < MaxEdge.Z);
                };

                //! Determinates if the box intersects with an other box.
                //! \param other: Other box to check a intersection with.
                //! \return Returns true if there is a intersection with the other box, 
                //! otherwise false.
                bool intersectsWithBox(const aabbox3d<T>& other) const
                {
                        return (MinEdge <= other.MaxEdge && MaxEdge >= other.MinEdge);
                }

                //! Returns if this box is completely inside the 'other' box.
                bool isFullInside(const aabbox3d<T>& other) const
                {
                        return MinEdge >= other.MinEdge && MaxEdge <= other.MaxEdge;
                }

                //! Tests if the box intersects with a line
                //! \param line: Line to test intersection with.
                //! \return Returns true if there is an intersection and false if not.
                bool intersectsWithLine(const line3d<T>& line) const
                {
                        return intersectsWithLine(line.getMiddle(), line.getVector().normalize(), 
                                        (T)(line.getLength() * 0.5));
                }

                //! Tests if the box intersects with a line
                //! \return Returns true if there is an intersection and false if not.
                bool intersectsWithLine(const vector3d<T>& linemiddle, 
                                        const vector3d<T>& linevect,
                                        T halflength) const
                {
                        const vector3d<T> e = getExtent() * (T)0.5;
                        const vector3d<T> t = getCenter() - linemiddle;

                        if ((fabs(t.X) > e.X + halflength * fabs(linevect.X)) || 
                                (fabs(t.Y) > e.Y + halflength * fabs(linevect.Y)) ||
                                (fabs(t.Z) > e.Z + halflength * fabs(linevect.Z)) )
                                return false;

                        T r = e.Y * (T)fabs(linevect.Z) + e.Z * (T)fabs(linevect.Y);
                        if (fabs(t.Y*linevect.Z - t.Z*linevect.Y) > r )
                                return false;

                        r = e.X * (T)fabs(linevect.Z) + e.Z * (T)fabs(linevect.X);
                        if (fabs(t.Z*linevect.X - t.X*linevect.Z) > r )
                                return false;

                        r = e.X * (T)fabs(linevect.Y) + e.Y * (T)fabs(linevect.X);
                        if (fabs(t.X*linevect.Y - t.Y*linevect.X) > r)
                                return false;

                        return true;
                }

                //! Classifies a relation with a plane.
                //! \param plane: Plane to classify relation to.
                //! \return Returns ISREL3D_FRONT if the box is in front of the plane,
                //! ISREL3D_BACK if the box is behind the plane, and
                //! ISREL3D_CLIPPED if it is on both sides of the plane.
                EIntersectionRelation3D classifyPlaneRelation(const plane3d<T>& plane) const
                {
                        vector3d<T> nearPoint(MaxEdge);
                        vector3d<T> farPoint(MinEdge);

                        if (plane.Normal.X > (T)0)
                        {
                                nearPoint.X = MinEdge.X;
                                farPoint.X = MaxEdge.X;
                        }

                        if (plane.Normal.Y > (T)0)
                        {
                                nearPoint.Y = MinEdge.Y;
                                farPoint.Y = MaxEdge.Y;
                        }

                        if (plane.Normal.Z > (T)0)
                        {
                                nearPoint.Z = MinEdge.Z;
                                farPoint.Z = MaxEdge.Z;
                        }

                        if (plane.Normal.dotProduct(nearPoint) + plane.D > (T)0)
                                return ISREL3D_FRONT;

                        if (plane.Normal.dotProduct(farPoint) + plane.D > (T)0)
                                return ISREL3D_CLIPPED;

                        return ISREL3D_BACK;
                }


                //! returns center of the bounding box
                vector3d<T> getCenter() const
                {
                        return (MinEdge + MaxEdge) / 2;
                }

                //! returns extend of the box
                vector3d<T> getExtent() const
                {
                        return MaxEdge - MinEdge;
                }


                //! stores all 8 edges of the box into a array
                //! \param edges: Pointer to array of 8 edges
                void getEdges(vector3d<T> *edges) const
                {
                        const core::vector3d<T> middle = getCenter();
                        const core::vector3d<T> diag = middle - MaxEdge;

                        /*
                        Edges are stored in this way:
                        Hey, am I an ascii artist, or what? :) niko.
                  /3--------/7
                 /  |      / |
                /   |     /  |
                1---------5  |
                |   2- - -| -6
                |  /      |  /
                |/        | /
                0---------4/ 
                        */

                        edges[0].set(middle.X + diag.X, middle.Y + diag.Y, middle.Z + diag.Z);
                        edges[1].set(middle.X + diag.X, middle.Y - diag.Y, middle.Z + diag.Z);
                        edges[2].set(middle.X + diag.X, middle.Y + diag.Y, middle.Z - diag.Z);
                        edges[3].set(middle.X + diag.X, middle.Y - diag.Y, middle.Z - diag.Z);
                        edges[4].set(middle.X - diag.X, middle.Y + diag.Y, middle.Z + diag.Z);
                        edges[5].set(middle.X - diag.X, middle.Y - diag.Y, middle.Z + diag.Z);
                        edges[6].set(middle.X - diag.X, middle.Y + diag.Y, middle.Z - diag.Z);
                        edges[7].set(middle.X - diag.X, middle.Y - diag.Y, middle.Z - diag.Z);
                }


                //! returns if the box is empty, which means that there is
                //! no space within the min and the max edge.
                bool isEmpty() const
                {
                        return MinEdge.equals ( MaxEdge );
                }

                //! repairs the box, if for example MinEdge and MaxEdge are swapped.
                void repair()
                {
                        T t;

                        if (MinEdge.X > MaxEdge.X)
                                { t=MinEdge.X; MinEdge.X = MaxEdge.X; MaxEdge.X=t; }
                        if (MinEdge.Y > MaxEdge.Y)
                                { t=MinEdge.Y; MinEdge.Y = MaxEdge.Y; MaxEdge.Y=t; }
                        if (MinEdge.Z > MaxEdge.Z)
                                { t=MinEdge.Z; MinEdge.Z = MaxEdge.Z; MaxEdge.Z=t; }
                }

                //! Calculates a new interpolated bounding box.
                //! \param other: other box to interpolate between
                //! \param d: value between 0.0f and 1.0f.
                aabbox3d<T> getInterpolated(const aabbox3d<T>& other, f32 d) const
                {
                        f32 inv = 1.0f - d;
                        return aabbox3d<T>((other.MinEdge*inv) + (MinEdge*d),
                                (other.MaxEdge*inv) + (MaxEdge*d));
                }

                // member variables
                
                vector3d<T> MinEdge;
                vector3d<T> MaxEdge;
};

        //! Typedef for a f32 3d bounding box.
        typedef aabbox3d<f32> aabbox3df;
        //! Typedef for an integer 3d bounding box.
        typedef aabbox3d<s32> aabbox3di;

} // end namespace core
} // end namespace irr

#endif