mirror of
https://github.com/minetest/minetest.git
synced 2024-12-04 21:43:44 +01:00
450 lines
13 KiB
C++
450 lines
13 KiB
C++
// 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
|
|
|
|
#pragma once
|
|
|
|
#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 furthest 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() :
|
|
BoundingRadius(0.f), FarNearDistance(0.f) {}
|
|
|
|
//! Copy Constructor
|
|
SViewFrustum(const SViewFrustum &other);
|
|
|
|
//! This constructor creates a view frustum based on a projection and/or view matrix.
|
|
//\param zClipFromZero: Clipping of z can be projected from 0 to w when true (D3D style) and from -w to w when false (OGL style).
|
|
SViewFrustum(const core::matrix4 &mat, bool zClipFromZero);
|
|
|
|
//! This constructor creates a view frustum based on a projection and/or view matrix.
|
|
//\param zClipFromZero: Clipping of z can be projected from 0 to w when true (D3D style) and from -w to w when false (OGL style).
|
|
inline void setFrom(const core::matrix4 &mat, bool zClipFromZero);
|
|
|
|
//! 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 and sphere based on the planes
|
|
inline void recalculateBoundingBox();
|
|
|
|
//! get the bounding sphere's radius (of an optimized sphere, not the AABB's)
|
|
float getBoundingRadius() const;
|
|
|
|
//! get the bounding sphere's radius (of an optimized sphere, not the AABB's)
|
|
core::vector3df getBoundingCenter() const;
|
|
|
|
//! the cam should tell the frustum the distance between far and near
|
|
void setFarNearDistance(float distance);
|
|
|
|
//! 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
|
|
};
|
|
|
|
//! recalculates the bounding sphere based on the planes
|
|
inline void recalculateBoundingSphere();
|
|
|
|
//! Hold a copy of important transform matrices
|
|
core::matrix4 Matrices[ETS_COUNT_FRUSTUM];
|
|
|
|
float BoundingRadius;
|
|
float FarNearDistance;
|
|
core::vector3df BoundingCenter;
|
|
};
|
|
|
|
/*!
|
|
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];
|
|
|
|
BoundingRadius = other.BoundingRadius;
|
|
FarNearDistance = other.FarNearDistance;
|
|
BoundingCenter = other.BoundingCenter;
|
|
}
|
|
|
|
inline SViewFrustum::SViewFrustum(const core::matrix4 &mat, bool zClipFromZero)
|
|
{
|
|
setFrom(mat, zClipFromZero);
|
|
}
|
|
|
|
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(getNearLeftUp());
|
|
boundingBox.addInternalPoint(getNearRightUp());
|
|
boundingBox.addInternalPoint(getNearLeftDown());
|
|
boundingBox.addInternalPoint(getNearRightDown());
|
|
boundingBox.addInternalPoint(getFarRightUp());
|
|
boundingBox.addInternalPoint(getFarLeftDown());
|
|
boundingBox.addInternalPoint(getFarRightDown());
|
|
boundingBox.addInternalPoint(getFarLeftUp());
|
|
|
|
// Also recalculate the bounding sphere when the bbox changes
|
|
recalculateBoundingSphere();
|
|
}
|
|
|
|
inline float SViewFrustum::getBoundingRadius() const
|
|
{
|
|
return BoundingRadius;
|
|
}
|
|
|
|
inline core::vector3df SViewFrustum::getBoundingCenter() const
|
|
{
|
|
return BoundingCenter;
|
|
}
|
|
|
|
inline void SViewFrustum::setFarNearDistance(float distance)
|
|
{
|
|
FarNearDistance = distance;
|
|
}
|
|
|
|
//! This constructor creates a view frustum based on a projection
|
|
//! and/or view matrix.
|
|
inline void SViewFrustum::setFrom(const core::matrix4 &mat, bool zClipFromZero)
|
|
{
|
|
// 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
|
|
if (zClipFromZero) {
|
|
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];
|
|
} else {
|
|
// near clipping plane
|
|
planes[VF_NEAR_PLANE].Normal.X = mat[3] + mat[2];
|
|
planes[VF_NEAR_PLANE].Normal.Y = mat[7] + mat[6];
|
|
planes[VF_NEAR_PLANE].Normal.Z = mat[11] + mat[10];
|
|
planes[VF_NEAR_PLANE].D = mat[15] + 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,
|
|
1.f - 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,
|
|
1.f - planes[i].getKnownIntersectionWithLine(line.start, line.end));
|
|
wasClipped = true;
|
|
}
|
|
}
|
|
return wasClipped;
|
|
}
|
|
|
|
inline void SViewFrustum::recalculateBoundingSphere()
|
|
{
|
|
// Find the center
|
|
const float shortlen = (getNearLeftUp() - getNearRightUp()).getLength();
|
|
const float longlen = (getFarLeftUp() - getFarRightUp()).getLength();
|
|
|
|
const float farlen = FarNearDistance;
|
|
const float fartocenter = (farlen + (shortlen - longlen) * (shortlen + longlen) / (4 * farlen)) / 2;
|
|
const float neartocenter = farlen - fartocenter;
|
|
|
|
BoundingCenter = cameraPosition + -planes[VF_NEAR_PLANE].Normal * neartocenter;
|
|
|
|
// Find the radius
|
|
core::vector3df dir[8];
|
|
dir[0] = getFarLeftUp() - BoundingCenter;
|
|
dir[1] = getFarRightUp() - BoundingCenter;
|
|
dir[2] = getFarLeftDown() - BoundingCenter;
|
|
dir[3] = getFarRightDown() - BoundingCenter;
|
|
dir[4] = getNearRightDown() - BoundingCenter;
|
|
dir[5] = getNearLeftDown() - BoundingCenter;
|
|
dir[6] = getNearRightUp() - BoundingCenter;
|
|
dir[7] = getNearLeftUp() - BoundingCenter;
|
|
|
|
u32 i = 0;
|
|
float diam[8] = {0.f};
|
|
|
|
for (i = 0; i < 8; ++i)
|
|
diam[i] = dir[i].getLengthSQ();
|
|
|
|
float longest = 0;
|
|
|
|
for (i = 0; i < 8; ++i) {
|
|
if (diam[i] > longest)
|
|
longest = diam[i];
|
|
}
|
|
|
|
BoundingRadius = sqrtf(longest);
|
|
}
|
|
|
|
} // end namespace scene
|
|
} // end namespace irr
|