BansheeEngine/CamelotUtility/Include/CmRay.h

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2011 Torus Knot Software Ltd

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-----------------------------------------------------------------------------
*/
#ifndef __Ray_H_
#define __Ray_H_

// Precompiler options
#include "CmPrerequisitesUtil.h"

#include "CmVector3.h"

namespace CamelotFramework {

	/** \addtogroup Core
	*  @{
	*/
	/** \addtogroup Math
	*  @{
	*/
	/** Representation of a ray in space, i.e. a line with an origin and direction. */
    class CM_UTILITY_EXPORT Ray
    {
    protected:
        Vector3 mOrigin;
        Vector3 mDirection;
    public:
        Ray():mOrigin(Vector3::ZERO), mDirection(Vector3::UNIT_Z) {}
        Ray(const Vector3& origin, const Vector3& direction)
            :mOrigin(origin), mDirection(direction) {}

        /** Sets the origin of the ray. */
        void setOrigin(const Vector3& origin) {mOrigin = origin;} 
        /** Gets the origin of the ray. */
        const Vector3& getOrigin(void) const {return mOrigin;} 

        /** Sets the direction of the ray. */
        void setDirection(const Vector3& dir) {mDirection = dir;} 
        /** Gets the direction of the ray. */
        const Vector3& getDirection(void) const {return mDirection;} 

		/** Gets the position of a point t units along the ray. */
		Vector3 getPoint(float t) const { 
			return Vector3(mOrigin + (mDirection * t));
		}
		
		/** Gets the position of a point t units along the ray. */
		Vector3 operator*(float t) const { 
			return getPoint(t);
		}

		/** Tests whether this ray intersects the given plane. 
		@returns A pair structure where the first element indicates whether
			an intersection occurs, and if true, the second element will
			indicate the distance along the ray at which it intersects. 
			This can be converted to a point in space by calling getPoint().
		*/
		std::pair<bool, float> intersects(const Plane& p) const;

		/** Tests whether this ray intersects the given sphere. 
		@returns A pair structure where the first element indicates whether
			an intersection occurs, and if true, the second element will
			indicate the distance along the ray at which it intersects. 
			This can be converted to a point in space by calling getPoint().
		*/
		std::pair<bool, float> intersects(const Sphere& s) const;

		/** Tests whether this ray intersects the given box. 
		@returns A pair structure where the first element indicates whether
			an intersection occurs, and if true, the second element will
			indicate the distance along the ray at which it intersects. 
			This can be converted to a point in space by calling getPoint().
		*/
		std::pair<bool, float> intersects(const AABox& box) const;

        /** Ray / triangle intersection, returns boolean result and distance.
        @param
            ray The ray.
        @param
            a The triangle's first vertex.
        @param
            b The triangle's second vertex.
        @param
            c The triangle's third vertex.
		@param 
			normal The triangle plane's normal (passed in rather than calculated
				on demand since the caller may already have it), doesn't need
                normalised since we don't care.
        @param
            positiveSide Intersect with "positive side" of the triangle
        @param
            negativeSide Intersect with "negative side" of the triangle
        @returns
            If the ray is intersects the triangle, a pair of <b>true</b> and the
            distance between intersection point and ray origin returned.
        @par
            If the ray isn't intersects the triangle, a pair of <b>false</b> and
            <b>0</b> returned.
        */
        std::pair<bool, float> intersects(const Vector3& a,
            const Vector3& b, const Vector3& c, const Vector3& normal,
            bool positiveSide = true, bool negativeSide = true) const;

    };
	/** @} */
	/** @} */

}
#endif