castletour/include/irrlicht/SViewFrustum.h

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2014-10-19 21:51:28 +00:00
// Copyright (C) 2002-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
#ifndef __S_VIEW_FRUSTUM_H_INCLUDED__
#define __S_VIEW_FRUSTUM_H_INCLUDED__
#include "plane3d.h"
#include "vector3d.h"
#include "line3d.h"
#include "aabbox3d.h"
#include "matrix4.h"
#include "IVideoDriver.h"
namespace irr
{
namespace scene
{
//! Defines the view frustum. That's the space visible by the camera.
/** The view frustum is enclosed by 6 planes. These six planes share
eight points. A bounding box around these eight points is also stored in
this structure.
*/
struct SViewFrustum
{
enum VFPLANES
{
//! Far plane of the frustum. That is the plane farest away from the eye.
VF_FAR_PLANE = 0,
//! Near plane of the frustum. That is the plane nearest to the eye.
VF_NEAR_PLANE,
//! Left plane of the frustum.
VF_LEFT_PLANE,
//! Right plane of the frustum.
VF_RIGHT_PLANE,
//! Bottom plane of the frustum.
VF_BOTTOM_PLANE,
//! Top plane of the frustum.
VF_TOP_PLANE,
//! Amount of planes enclosing the view frustum. Should be 6.
VF_PLANE_COUNT
};
//! Default Constructor
SViewFrustum() {}
//! Copy Constructor
SViewFrustum(const SViewFrustum& other);
//! This constructor creates a view frustum based on a projection and/or view matrix.
SViewFrustum(const core::matrix4& mat);
//! This constructor creates a view frustum based on a projection and/or view matrix.
inline void setFrom(const core::matrix4& mat);
//! transforms the frustum by the matrix
/** \param mat: Matrix by which the view frustum is transformed.*/
void transform(const core::matrix4& mat);
//! returns the point which is on the far left upper corner inside the the view frustum.
core::vector3df getFarLeftUp() const;
//! returns the point which is on the far left bottom corner inside the the view frustum.
core::vector3df getFarLeftDown() const;
//! returns the point which is on the far right top corner inside the the view frustum.
core::vector3df getFarRightUp() const;
//! returns the point which is on the far right bottom corner inside the the view frustum.
core::vector3df getFarRightDown() const;
//! returns the point which is on the near left upper corner inside the the view frustum.
core::vector3df getNearLeftUp() const;
//! returns the point which is on the near left bottom corner inside the the view frustum.
core::vector3df getNearLeftDown() const;
//! returns the point which is on the near right top corner inside the the view frustum.
core::vector3df getNearRightUp() const;
//! returns the point which is on the near right bottom corner inside the the view frustum.
core::vector3df getNearRightDown() const;
//! returns a bounding box enclosing the whole view frustum
const core::aabbox3d<f32> &getBoundingBox() const;
//! recalculates the bounding box member based on the planes
inline void recalculateBoundingBox();
//! get the given state's matrix based on frustum E_TRANSFORMATION_STATE
core::matrix4& getTransform( video::E_TRANSFORMATION_STATE state);
//! get the given state's matrix based on frustum E_TRANSFORMATION_STATE
const core::matrix4& getTransform( video::E_TRANSFORMATION_STATE state) const;
//! clips a line to the view frustum.
/** \return True if the line was clipped, false if not */
bool clipLine(core::line3d<f32>& line) const;
//! the position of the camera
core::vector3df cameraPosition;
//! all planes enclosing the view frustum.
core::plane3d<f32> planes[VF_PLANE_COUNT];
//! bounding box around the view frustum
core::aabbox3d<f32> boundingBox;
private:
//! Hold a copy of important transform matrices
enum E_TRANSFORMATION_STATE_FRUSTUM
{
ETS_VIEW = 0,
ETS_PROJECTION = 1,
ETS_COUNT_FRUSTUM
};
//! Hold a copy of important transform matrices
core::matrix4 Matrices[ETS_COUNT_FRUSTUM];
};
/*!
Copy constructor ViewFrustum
*/
inline SViewFrustum::SViewFrustum(const SViewFrustum& other)
{
cameraPosition=other.cameraPosition;
boundingBox=other.boundingBox;
u32 i;
for (i=0; i<VF_PLANE_COUNT; ++i)
planes[i]=other.planes[i];
for (i=0; i<ETS_COUNT_FRUSTUM; ++i)
Matrices[i]=other.Matrices[i];
}
inline SViewFrustum::SViewFrustum(const core::matrix4& mat)
{
setFrom ( mat );
}
inline void SViewFrustum::transform(const core::matrix4& mat)
{
for (u32 i=0; i<VF_PLANE_COUNT; ++i)
mat.transformPlane(planes[i]);
mat.transformVect(cameraPosition);
recalculateBoundingBox();
}
inline core::vector3df SViewFrustum::getFarLeftUp() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_FAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_TOP_PLANE],
planes[scene::SViewFrustum::VF_LEFT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getFarLeftDown() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_FAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_BOTTOM_PLANE],
planes[scene::SViewFrustum::VF_LEFT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getFarRightUp() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_FAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_TOP_PLANE],
planes[scene::SViewFrustum::VF_RIGHT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getFarRightDown() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_FAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_BOTTOM_PLANE],
planes[scene::SViewFrustum::VF_RIGHT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getNearLeftUp() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_NEAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_TOP_PLANE],
planes[scene::SViewFrustum::VF_LEFT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getNearLeftDown() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_NEAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_BOTTOM_PLANE],
planes[scene::SViewFrustum::VF_LEFT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getNearRightUp() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_NEAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_TOP_PLANE],
planes[scene::SViewFrustum::VF_RIGHT_PLANE], p);
return p;
}
inline core::vector3df SViewFrustum::getNearRightDown() const
{
core::vector3df p;
planes[scene::SViewFrustum::VF_NEAR_PLANE].getIntersectionWithPlanes(
planes[scene::SViewFrustum::VF_BOTTOM_PLANE],
planes[scene::SViewFrustum::VF_RIGHT_PLANE], p);
return p;
}
inline const core::aabbox3d<f32> &SViewFrustum::getBoundingBox() const
{
return boundingBox;
}
inline void SViewFrustum::recalculateBoundingBox()
{
boundingBox.reset ( cameraPosition );
boundingBox.addInternalPoint(getFarLeftUp());
boundingBox.addInternalPoint(getFarRightUp());
boundingBox.addInternalPoint(getFarLeftDown());
boundingBox.addInternalPoint(getFarRightDown());
}
//! This constructor creates a view frustum based on a projection
//! and/or view matrix.
inline void SViewFrustum::setFrom(const core::matrix4& mat)
{
// left clipping plane
planes[VF_LEFT_PLANE].Normal.X = mat[3 ] + mat[0];
planes[VF_LEFT_PLANE].Normal.Y = mat[7 ] + mat[4];
planes[VF_LEFT_PLANE].Normal.Z = mat[11] + mat[8];
planes[VF_LEFT_PLANE].D = mat[15] + mat[12];
// right clipping plane
planes[VF_RIGHT_PLANE].Normal.X = mat[3 ] - mat[0];
planes[VF_RIGHT_PLANE].Normal.Y = mat[7 ] - mat[4];
planes[VF_RIGHT_PLANE].Normal.Z = mat[11] - mat[8];
planes[VF_RIGHT_PLANE].D = mat[15] - mat[12];
// top clipping plane
planes[VF_TOP_PLANE].Normal.X = mat[3 ] - mat[1];
planes[VF_TOP_PLANE].Normal.Y = mat[7 ] - mat[5];
planes[VF_TOP_PLANE].Normal.Z = mat[11] - mat[9];
planes[VF_TOP_PLANE].D = mat[15] - mat[13];
// bottom clipping plane
planes[VF_BOTTOM_PLANE].Normal.X = mat[3 ] + mat[1];
planes[VF_BOTTOM_PLANE].Normal.Y = mat[7 ] + mat[5];
planes[VF_BOTTOM_PLANE].Normal.Z = mat[11] + mat[9];
planes[VF_BOTTOM_PLANE].D = mat[15] + mat[13];
// far clipping plane
planes[VF_FAR_PLANE].Normal.X = mat[3 ] - mat[2];
planes[VF_FAR_PLANE].Normal.Y = mat[7 ] - mat[6];
planes[VF_FAR_PLANE].Normal.Z = mat[11] - mat[10];
planes[VF_FAR_PLANE].D = mat[15] - mat[14];
// near clipping plane
planes[VF_NEAR_PLANE].Normal.X = mat[2];
planes[VF_NEAR_PLANE].Normal.Y = mat[6];
planes[VF_NEAR_PLANE].Normal.Z = mat[10];
planes[VF_NEAR_PLANE].D = mat[14];
// normalize normals
u32 i;
for ( i=0; i != VF_PLANE_COUNT; ++i)
{
const f32 len = -core::reciprocal_squareroot(
planes[i].Normal.getLengthSQ());
planes[i].Normal *= len;
planes[i].D *= len;
}
// make bounding box
recalculateBoundingBox();
}
/*!
View Frustum depends on Projection & View Matrix
*/
inline core::matrix4& SViewFrustum::getTransform(video::E_TRANSFORMATION_STATE state )
{
u32 index = 0;
switch ( state )
{
case video::ETS_PROJECTION:
index = SViewFrustum::ETS_PROJECTION; break;
case video::ETS_VIEW:
index = SViewFrustum::ETS_VIEW; break;
default:
break;
}
return Matrices [ index ];
}
/*!
View Frustum depends on Projection & View Matrix
*/
inline const core::matrix4& SViewFrustum::getTransform(video::E_TRANSFORMATION_STATE state ) const
{
u32 index = 0;
switch ( state )
{
case video::ETS_PROJECTION:
index = SViewFrustum::ETS_PROJECTION; break;
case video::ETS_VIEW:
index = SViewFrustum::ETS_VIEW; break;
default:
break;
}
return Matrices [ index ];
}
//! Clips a line to the frustum
inline bool SViewFrustum::clipLine(core::line3d<f32>& line) const
{
bool wasClipped = false;
for (u32 i=0; i < VF_PLANE_COUNT; ++i)
{
if (planes[i].classifyPointRelation(line.start) == core::ISREL3D_FRONT)
{
line.start = line.start.getInterpolated(line.end,
planes[i].getKnownIntersectionWithLine(line.start, line.end));
wasClipped = true;
}
if (planes[i].classifyPointRelation(line.end) == core::ISREL3D_FRONT)
{
line.end = line.start.getInterpolated(line.end,
planes[i].getKnownIntersectionWithLine(line.start, line.end));
wasClipped = true;
}
}
return wasClipped;
}
} // end namespace scene
} // end namespace irr
#endif