Files
axyz/include/Engine/Core/Octree.h
T
Jace 2c0f66d9c7 Merge remote-tracking branch 'origin/master' into WeaponSystem
# Conflicts:
#	include/Engine/Collision/FillFrustumOctreeSystem.h
#	include/Engine/Core/Octree.h
#	include/Engine/Rendering/RenderSystem.h
#	include/Game/Game.h
#	resources/DefaultInput.ini
#	resources/Schema/Components.xsd
#	resources/Schema/Entities/Player.xml
#	resources/Schema/Types/Entity.xsd
#	src/Engine/Rendering/RenderSystem.cpp
#	src/Game/Game.cpp
#	src/Game/Systems/PlayerMovementSystem.cpp
2016-02-10 17:02:00 +01:00

285 lines
9.1 KiB
C++

#ifndef Octree_h__
#define Octree_h__
#include <type_traits>
#include "../Common.h"
#include "AABB.h"
#include "Frustum.h"
#include "Ray.h"
namespace OctSpace
{
struct Output;
struct ContainedObject;
struct Child;
}
//T needs to be AABB, or inherit from AABB.
//T also needs to have a default constructor.
template<typename T>
class Octree
{
public:
Octree() = delete;
~Octree();
//For the root Octree, [octreeBounds] should be a box containing the entire level.
Octree(const AABB& octreeBounds, int subDivisions);
//We cannot copy the Octree as of now, because of the recursive dynamic allocation.
//Define these if the Octree suddenly needs to be copied, think of the children Child* ptrs.
Octree(const Octree& other) = delete;
Octree(const Octree&& other) = delete;
Octree& operator= (const Octree& other) = delete;
//Add a dynamic object (one that moves around) into the tree.
void AddDynamicObject(const T& object);
//Add a static object (that does not move) into the tree.
void AddStaticObject(const T& object);
//Get the objects that are in the same area as the input [box], the objects are put in [outObjects].
//The type Box must be AABB, or inherit from AABB.
template<typename Box>
void ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects);
//Get the objects that are inside the frustum, the objects are put in outObjects.
void ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects);
//Empty the tree of all objects, static and dynamic.
void ClearObjects();
//Empty the tree of all dynamic objects. Static objects remain in the tree.
void ClearDynamicObjects();
//Returns true if the ray collides with something in the tree. Result is written to [data].
bool RayCollides(const Ray& ray, OctSpace::Output& data);
//Returns true if the box collides with something in the tree.
//On collision with a box, that box is written to [outBoxIntersected].
//Note: More efficient than calling ObjectsInSameRegion from outside and testing there.
bool BoxCollides(const AABB& boxToTest, AABB& outBoxIntersected);
private:
OctSpace::Child* m_Root;
std::vector<OctSpace::ContainedObject> m_StaticObjects;
std::vector<OctSpace::ContainedObject> m_DynamicObjects;
void falsifyObjectChecks();
};
namespace OctSpace
{
struct Output
{
float CollideDistance;
};
struct ContainedObject
{
ContainedObject()
: Box(nullptr)
, Checked(false)
{}
template<typename BoxlikeObject>
ContainedObject(const BoxlikeObject& box)
: Box(new BoxlikeObject(box))
, Checked(false)
{}
std::unique_ptr<AABB> Box;
bool Checked;
};
struct Child
{
~Child();
Child(const AABB& octTreeBounds,
int subDivisions,
std::vector<ContainedObject>& staticObjects,
std::vector<ContainedObject>& dynamicObjects);
Child(const Child& other) = delete;
Child(const Child&& other) = delete;
Child& operator= (const Child& other) = delete;
void AddDynamicObject(const AABB& box);
void AddStaticObject(const AABB& box);
template<typename T, typename Box>
void ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects) const;
template<typename T>
void ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects, bool takeAllDontTest) const;
void ClearObjects();
void ClearDynamicObjects();
bool RayCollides(const Ray& ray, Output& data) const;
bool BoxCollides(const AABB& boxToTest, AABB& outBoxIntersected) const;
Child* m_Children[8];
//Indices into the lists in Octree.
std::vector<int> m_StaticObjIndices;
std::vector<int> m_DynamicObjIndices;
AABB m_Box;
//Reference to the lists in Octree.
std::vector<ContainedObject>& m_StaticObjectsRef;
std::vector<ContainedObject>& m_DynamicObjectsRef;
inline bool hasChildren() const { return m_Children[0] != nullptr; }
int childIndexContainingPoint(const glm::vec3& point) const;
std::vector<int> childIndicesContainingBox(const AABB& box) const;
};
}
template<typename T>
Octree<T>::Octree(const AABB& octTreeBounds, int subDivisions)
: m_Root(new OctSpace::Child(octTreeBounds, subDivisions, m_StaticObjects, m_DynamicObjects))
{
static_assert(std::is_base_of<AABB, T>::value, "template argument type T in Octree must be a subclass of AABB.");
}
template<typename T>
Octree<T>::~Octree()
{
delete m_Root;
}
template<typename T>
void Octree<T>::AddDynamicObject(const T& object)
{
m_Root->AddDynamicObject(object);
m_DynamicObjects.emplace_back(object);
}
template<typename T>
void Octree<T>::AddStaticObject(const T& object)
{
m_Root->AddStaticObject(object);
m_StaticObjects.emplace_back(object);
}
template<typename T>
template<typename Box>
void Octree<T>::ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects)
{
static_assert(std::is_base_of<AABB, Box>::value, "template argument type Box in Octree<T>::ObjectsInSameRegion must be a subclass of AABB.");
falsifyObjectChecks();
m_Root->ObjectsInSameRegion(box, outObjects);
}
template<typename T>
void Octree<T>::ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects)
{
falsifyObjectChecks();
m_Root->ObjectsInFrustum(frustum, outObjects, false);
}
template<typename T>
void Octree<T>::ClearObjects()
{
m_StaticObjects.clear();
m_DynamicObjects.clear();
m_Root->ClearObjects();
}
template<typename T>
void Octree<T>::ClearDynamicObjects()
{
m_DynamicObjects.clear();
m_Root->ClearDynamicObjects();
}
template<typename T>
bool Octree<T>::RayCollides(const Ray& ray, OctSpace::Output& data)
{
falsifyObjectChecks();
data.CollideDistance = -1;
return m_Root->RayCollides(ray, data);
}
template<typename T>
bool Octree<T>::BoxCollides(const AABB& boxToTest, AABB& outBoxIntersected)
{
falsifyObjectChecks();
return m_Root->BoxCollides(boxToTest, outBoxIntersected);
}
template<typename T>
void Octree<T>::falsifyObjectChecks()
{
for (auto& obj : m_StaticObjects) {
obj.Checked = false;
}
for (auto& obj : m_DynamicObjects) {
obj.Checked = false;
}
}
template<typename T, typename Box>
void OctSpace::Child::ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects) const
{
if (hasChildren()) {
for (auto i : childIndicesContainingBox(box)) {
m_Children[i]->ObjectsInSameRegion(box, outObjects);
}
} else {
size_t startIndex = outObjects.size();
int numDuplicates = 0;
outObjects.resize(outObjects.size() + m_StaticObjIndices.size() + m_DynamicObjIndices.size());
for (size_t i = 0; i < m_StaticObjIndices.size(); ++i) {
ContainedObject& obj = m_StaticObjectsRef[m_StaticObjIndices[i]];
if (obj.Checked) {
++numDuplicates;
} else {
obj.Checked = true;
outObjects[startIndex + i - numDuplicates] = *static_cast<T*>(obj.Box.get());
}
}
for (size_t i = 0; i < m_DynamicObjIndices.size(); ++i) {
ContainedObject& obj = m_DynamicObjectsRef[m_DynamicObjIndices[i]];
if (obj.Checked) {
++numDuplicates;
} else {
obj.Checked = true;
outObjects[startIndex + i - numDuplicates] = *static_cast<T*>(obj.Box.get());
}
}
for (size_t i = 0; i < numDuplicates; ++i) {
outObjects.pop_back();
}
}
}
template<typename T>
void OctSpace::Child::ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects, bool takeAllDontTest) const
{
if (hasChildren()) {
for (const Child* c : m_Children) {
Frustum::Output out = Frustum::Output::Inside;
if (!takeAllDontTest) {
out = frustum.VsAABB(c->m_Box);
if (out == Frustum::Output::Outside) {
continue;
}
}
c->ObjectsInFrustum(frustum, outObjects, out == Frustum::Output::Inside);
}
} else {
size_t startIndex = outObjects.size();
int numDuplicates = 0;
outObjects.resize(outObjects.size() + m_StaticObjIndices.size() + m_DynamicObjIndices.size());
for (size_t i = 0; i < m_StaticObjIndices.size(); ++i) {
ContainedObject& obj = m_StaticObjectsRef[m_StaticObjIndices[i]];
if (obj.Checked || frustum.VsAABB(*obj.Box) == Frustum::Output::Outside) {
++numDuplicates;
} else {
obj.Checked = true;
outObjects[startIndex + i - numDuplicates] = *static_cast<T*>(obj.Box.get());
}
}
for (size_t i = 0; i < m_DynamicObjIndices.size(); ++i) {
ContainedObject& obj = m_DynamicObjectsRef[m_DynamicObjIndices[i]];
if (obj.Checked || frustum.VsAABB(*obj.Box) == Frustum::Output::Outside) {
++numDuplicates;
} else {
obj.Checked = true;
outObjects[startIndex + i - numDuplicates] = *static_cast<T*>(obj.Box.get());
}
}
for (size_t i = 0; i < numDuplicates; ++i) {
outObjects.pop_back();
}
}
}
#endif