mirror of
https://github.com/opencv/opencv.git
synced 2024-12-01 14:59:54 +08:00
411 lines
14 KiB
C++
411 lines
14 KiB
C++
///////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Copyright (c) 2011, Industrial Light & Magic, a division of Lucas
|
|
// Digital Ltd. LLC
|
|
//
|
|
// All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions are
|
|
// met:
|
|
// * Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// * Redistributions in binary form must reproduce the above
|
|
// copyright notice, this list of conditions and the following disclaimer
|
|
// in the documentation and/or other materials provided with the
|
|
// distribution.
|
|
// * Neither the name of Industrial Light & Magic nor the names of
|
|
// its contributors may be used to endorse or promote products derived
|
|
// from this software without specific prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
#ifndef INCLUDED_IMATHFRUSTUMTEST_H
|
|
#define INCLUDED_IMATHFRUSTUMTEST_H
|
|
|
|
//-------------------------------------------------------------------------
|
|
//
|
|
// This file contains algorithms applied to or in conjunction with
|
|
// Frustum visibility testing (Imath::Frustum).
|
|
//
|
|
// Methods for frustum-based rejection of primitives are contained here.
|
|
//
|
|
//-------------------------------------------------------------------------
|
|
|
|
#include "ImathFrustum.h"
|
|
#include "ImathBox.h"
|
|
#include "ImathSphere.h"
|
|
#include "ImathMatrix.h"
|
|
#include "ImathVec.h"
|
|
|
|
namespace Imath {
|
|
|
|
/////////////////////////////////////////////////////////////////
|
|
// FrustumTest
|
|
//
|
|
// template class FrustumTest<T>
|
|
//
|
|
// This is a helper class, designed to accelerate the case
|
|
// where many tests are made against the same frustum.
|
|
// That's a really common case.
|
|
//
|
|
// The acceleration is achieved by pre-computing the planes of
|
|
// the frustum, along with the ablsolute values of the plane normals.
|
|
//
|
|
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////
|
|
// How to use this
|
|
//
|
|
// Given that you already have:
|
|
// Imath::Frustum myFrustum
|
|
// IMath::Matrix44 myCameraWorldMatrix
|
|
//
|
|
// First, make a frustum test object:
|
|
// FrustumTest myFrustumTest(myFrustum, myCameraWorldMatrix)
|
|
//
|
|
// Whenever the camera or frustum changes, call:
|
|
// myFrustumTest.setFrustum(myFrustum, myCameraWorldMatrix)
|
|
//
|
|
// For each object you want to test for visibility, call:
|
|
// myFrustumTest.isVisible(myBox)
|
|
// myFrustumTest.isVisible(mySphere)
|
|
// myFrustumTest.isVisible(myVec3)
|
|
// myFrustumTest.completelyContains(myBox)
|
|
// myFrustumTest.completelyContains(mySphere)
|
|
//
|
|
|
|
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////
|
|
// Explanation of how it works
|
|
//
|
|
//
|
|
// We store six world-space Frustum planes (nx, ny, nz, offset)
|
|
//
|
|
// Points: To test a Vec3 for visibility, test it against each plane
|
|
// using the normal (v dot n - offset) method. (the result is exact)
|
|
//
|
|
// BBoxes: To test an axis-aligned bbox, test the center against each plane
|
|
// using the normal (v dot n - offset) method, but offset by the
|
|
// box extents dot the abs of the plane normal. (the result is NOT
|
|
// exact, but will not return false-negatives.)
|
|
//
|
|
// Spheres: To test a sphere, test the center against each plane
|
|
// using the normal (v dot n - offset) method, but offset by the
|
|
// sphere's radius. (the result is NOT exact, but will not return
|
|
// false-negatives.)
|
|
//
|
|
//
|
|
// SPECIAL NOTE: "Where are the dot products?"
|
|
// Actual dot products are currently slow for most SIMD architectures.
|
|
// In order to keep this code optimization-ready, the dot products
|
|
// are all performed using vector adds and multipies.
|
|
//
|
|
// In order to do this, the plane equations are stored in "transpose"
|
|
// form, with the X components grouped into an X vector, etc.
|
|
//
|
|
|
|
|
|
template <class T>
|
|
class FrustumTest
|
|
{
|
|
public:
|
|
FrustumTest()
|
|
{
|
|
Frustum<T> frust;
|
|
Matrix44<T> cameraMat;
|
|
cameraMat.makeIdentity();
|
|
setFrustum(frust, cameraMat);
|
|
}
|
|
FrustumTest(Frustum<T> &frustum, const Matrix44<T> &cameraMat)
|
|
{
|
|
setFrustum(frustum, cameraMat);
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// setFrustum()
|
|
// This updates the frustum test with a new frustum and matrix.
|
|
// This should usually be called just once per frame.
|
|
void setFrustum(Frustum<T> &frustum, const Matrix44<T> &cameraMat);
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// isVisible()
|
|
// Check to see if shapes are visible.
|
|
bool isVisible(const Sphere3<T> &sphere) const;
|
|
bool isVisible(const Box<Vec3<T> > &box) const;
|
|
bool isVisible(const Vec3<T> &vec) const;
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// completelyContains()
|
|
// Check to see if shapes are entirely contained.
|
|
bool completelyContains(const Sphere3<T> &sphere) const;
|
|
bool completelyContains(const Box<Vec3<T> > &box) const;
|
|
|
|
// These next items are kept primarily for debugging tools.
|
|
// It's useful for drawing the culling environment, and also
|
|
// for getting an "outside view" of the culling frustum.
|
|
Imath::Matrix44<T> cameraMat() const {return cameraMatrix;}
|
|
Imath::Frustum<T> currentFrustum() const {return currFrustum;}
|
|
|
|
protected:
|
|
// To understand why the planes are stored this way, see
|
|
// the SPECIAL NOTE above.
|
|
Vec3<T> planeNormX[2]; // The X compunents from 6 plane equations
|
|
Vec3<T> planeNormY[2]; // The Y compunents from 6 plane equations
|
|
Vec3<T> planeNormZ[2]; // The Z compunents from 6 plane equations
|
|
|
|
Vec3<T> planeOffsetVec[2]; // The distance offsets from 6 plane equations
|
|
|
|
// The absolute values are stored to assist with bounding box tests.
|
|
Vec3<T> planeNormAbsX[2]; // The abs(X) compunents from 6 plane equations
|
|
Vec3<T> planeNormAbsY[2]; // The abs(X) compunents from 6 plane equations
|
|
Vec3<T> planeNormAbsZ[2]; // The abs(X) compunents from 6 plane equations
|
|
|
|
// These are kept primarily for debugging tools.
|
|
Frustum<T> currFrustum;
|
|
Matrix44<T> cameraMatrix;
|
|
};
|
|
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// setFrustum()
|
|
// This should usually only be called once per frame, or however
|
|
// often the camera moves.
|
|
template<class T>
|
|
void FrustumTest<T>::setFrustum(Frustum<T> &frustum,
|
|
const Matrix44<T> &cameraMat)
|
|
{
|
|
Plane3<T> frustumPlanes[6];
|
|
frustum.planes(frustumPlanes, cameraMat);
|
|
|
|
// Here's where we effectively transpose the plane equations.
|
|
// We stuff all six X's into the two planeNormX vectors, etc.
|
|
for (int i = 0; i < 2; ++i)
|
|
{
|
|
int index = i * 3;
|
|
|
|
planeNormX[i] = Vec3<T>(frustumPlanes[index + 0].normal.x,
|
|
frustumPlanes[index + 1].normal.x,
|
|
frustumPlanes[index + 2].normal.x);
|
|
planeNormY[i] = Vec3<T>(frustumPlanes[index + 0].normal.y,
|
|
frustumPlanes[index + 1].normal.y,
|
|
frustumPlanes[index + 2].normal.y);
|
|
planeNormZ[i] = Vec3<T>(frustumPlanes[index + 0].normal.z,
|
|
frustumPlanes[index + 1].normal.z,
|
|
frustumPlanes[index + 2].normal.z);
|
|
|
|
planeNormAbsX[i] = Vec3<T>(Imath::abs(planeNormX[i].x),
|
|
Imath::abs(planeNormX[i].y),
|
|
Imath::abs(planeNormX[i].z));
|
|
planeNormAbsY[i] = Vec3<T>(Imath::abs(planeNormY[i].x),
|
|
Imath::abs(planeNormY[i].y),
|
|
Imath::abs(planeNormY[i].z));
|
|
planeNormAbsZ[i] = Vec3<T>(Imath::abs(planeNormZ[i].x),
|
|
Imath::abs(planeNormZ[i].y),
|
|
Imath::abs(planeNormZ[i].z));
|
|
|
|
planeOffsetVec[i] = Vec3<T>(frustumPlanes[index + 0].distance,
|
|
frustumPlanes[index + 1].distance,
|
|
frustumPlanes[index + 2].distance);
|
|
}
|
|
currFrustum = frustum;
|
|
cameraMatrix = cameraMat;
|
|
}
|
|
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// isVisible(Sphere)
|
|
// Returns true if any part of the sphere is inside
|
|
// the frustum.
|
|
// The result MAY return close false-positives, but not false-negatives.
|
|
//
|
|
template<typename T>
|
|
bool FrustumTest<T>::isVisible(const Sphere3<T> &sphere) const
|
|
{
|
|
Vec3<T> center = sphere.center;
|
|
Vec3<T> radiusVec = Vec3<T>(sphere.radius, sphere.radius, sphere.radius);
|
|
|
|
// This is a vertical dot-product on three vectors at once.
|
|
Vec3<T> d0 = planeNormX[0] * center.x
|
|
+ planeNormY[0] * center.y
|
|
+ planeNormZ[0] * center.z
|
|
- radiusVec
|
|
- planeOffsetVec[0];
|
|
|
|
if (d0.x >= 0 || d0.y >= 0 || d0.z >= 0)
|
|
return false;
|
|
|
|
Vec3<T> d1 = planeNormX[1] * center.x
|
|
+ planeNormY[1] * center.y
|
|
+ planeNormZ[1] * center.z
|
|
- radiusVec
|
|
- planeOffsetVec[1];
|
|
|
|
if (d1.x >= 0 || d1.y >= 0 || d1.z >= 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// completelyContains(Sphere)
|
|
// Returns true if every part of the sphere is inside
|
|
// the frustum.
|
|
// The result MAY return close false-negatives, but not false-positives.
|
|
//
|
|
template<typename T>
|
|
bool FrustumTest<T>::completelyContains(const Sphere3<T> &sphere) const
|
|
{
|
|
Vec3<T> center = sphere.center;
|
|
Vec3<T> radiusVec = Vec3<T>(sphere.radius, sphere.radius, sphere.radius);
|
|
|
|
// This is a vertical dot-product on three vectors at once.
|
|
Vec3<T> d0 = planeNormX[0] * center.x
|
|
+ planeNormY[0] * center.y
|
|
+ planeNormZ[0] * center.z
|
|
+ radiusVec
|
|
- planeOffsetVec[0];
|
|
|
|
if (d0.x >= 0 || d0.y >= 0 || d0.z >= 0)
|
|
return false;
|
|
|
|
Vec3<T> d1 = planeNormX[1] * center.x
|
|
+ planeNormY[1] * center.y
|
|
+ planeNormZ[1] * center.z
|
|
+ radiusVec
|
|
- planeOffsetVec[1];
|
|
|
|
if (d1.x >= 0 || d1.y >= 0 || d1.z >= 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// isVisible(Box)
|
|
// Returns true if any part of the axis-aligned box
|
|
// is inside the frustum.
|
|
// The result MAY return close false-positives, but not false-negatives.
|
|
//
|
|
template<typename T>
|
|
bool FrustumTest<T>::isVisible(const Box<Vec3<T> > &box) const
|
|
{
|
|
Vec3<T> center = (box.min + box.max) / 2;
|
|
Vec3<T> extent = (box.max - center);
|
|
|
|
// This is a vertical dot-product on three vectors at once.
|
|
Vec3<T> d0 = planeNormX[0] * center.x
|
|
+ planeNormY[0] * center.y
|
|
+ planeNormZ[0] * center.z
|
|
- planeNormAbsX[0] * extent.x
|
|
- planeNormAbsY[0] * extent.y
|
|
- planeNormAbsZ[0] * extent.z
|
|
- planeOffsetVec[0];
|
|
|
|
if (d0.x >= 0 || d0.y >= 0 || d0.z >= 0)
|
|
return false;
|
|
|
|
Vec3<T> d1 = planeNormX[1] * center.x
|
|
+ planeNormY[1] * center.y
|
|
+ planeNormZ[1] * center.z
|
|
- planeNormAbsX[1] * extent.x
|
|
- planeNormAbsY[1] * extent.y
|
|
- planeNormAbsZ[1] * extent.z
|
|
- planeOffsetVec[1];
|
|
|
|
if (d1.x >= 0 || d1.y >= 0 || d1.z >= 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// completelyContains(Box)
|
|
// Returns true if every part of the axis-aligned box
|
|
// is inside the frustum.
|
|
// The result MAY return close false-negatives, but not false-positives.
|
|
//
|
|
template<typename T>
|
|
bool FrustumTest<T>::completelyContains(const Box<Vec3<T> > &box) const
|
|
{
|
|
Vec3<T> center = (box.min + box.max) / 2;
|
|
Vec3<T> extent = (box.max - center);
|
|
|
|
// This is a vertical dot-product on three vectors at once.
|
|
Vec3<T> d0 = planeNormX[0] * center.x
|
|
+ planeNormY[0] * center.y
|
|
+ planeNormZ[0] * center.z
|
|
+ planeNormAbsX[0] * extent.x
|
|
+ planeNormAbsY[0] * extent.y
|
|
+ planeNormAbsZ[0] * extent.z
|
|
- planeOffsetVec[0];
|
|
|
|
if (d0.x >= 0 || d0.y >= 0 || d0.z >= 0)
|
|
return false;
|
|
|
|
Vec3<T> d1 = planeNormX[1] * center.x
|
|
+ planeNormY[1] * center.y
|
|
+ planeNormZ[1] * center.z
|
|
+ planeNormAbsX[1] * extent.x
|
|
+ planeNormAbsY[1] * extent.y
|
|
+ planeNormAbsZ[1] * extent.z
|
|
- planeOffsetVec[1];
|
|
|
|
if (d1.x >= 0 || d1.y >= 0 || d1.z >= 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
////////////////////////////////////////////////////////////////////
|
|
// isVisible(Vec3)
|
|
// Returns true if the point is inside the frustum.
|
|
//
|
|
template<typename T>
|
|
bool FrustumTest<T>::isVisible(const Vec3<T> &vec) const
|
|
{
|
|
// This is a vertical dot-product on three vectors at once.
|
|
Vec3<T> d0 = (planeNormX[0] * vec.x)
|
|
+ (planeNormY[0] * vec.y)
|
|
+ (planeNormZ[0] * vec.z)
|
|
- planeOffsetVec[0];
|
|
|
|
if (d0.x >= 0 || d0.y >= 0 || d0.z >= 0)
|
|
return false;
|
|
|
|
Vec3<T> d1 = (planeNormX[1] * vec.x)
|
|
+ (planeNormY[1] * vec.y)
|
|
+ (planeNormZ[1] * vec.z)
|
|
- planeOffsetVec[1];
|
|
|
|
if (d1.x >= 0 || d1.y >= 0 || d1.z >= 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
typedef FrustumTest<float> FrustumTestf;
|
|
typedef FrustumTest<double> FrustumTestd;
|
|
|
|
} //namespace Imath
|
|
|
|
#endif
|