A quadtree-based terrain implementation suitable for large data sets.
Near cells are rendered with alpha splatting, distant cells are merged together in batches and have their layers pre-rendered onto a composite map.
Cracks at LOD transitions are avoided using stitching. More...

#include <world.hpp>

Public Types
enum	IndexBufferFlags { IBF_North = 1 << 0, IBF_East = 1 << 1, IBF_South = 1 << 2, IBF_West = 1 << 3 }
Public Member Functions
	World (Loading::Listener loadingListener, Ogre::SceneManager sceneMgr, Storage *storage, int visiblityFlags, bool distantLand, bool shaders)
	~World ()
void	setLoadingListener (Loading::Listener *loadingListener)
bool	getDistantLandEnabled ()
bool	getShadersEnabled ()
bool	getShadowsEnabled ()
bool	getSplitShadowsEnabled ()
float	getHeightAt (const Ogre::Vector3 &worldPos)
void	update (const Ogre::Vector3 &cameraPos)
Ogre::AxisAlignedBox	getWorldBoundingBox (const Ogre::Vector2 &center)
	Get the world bounding box of a chunk of terrain centered at center.
Ogre::SceneManager *	getSceneManager ()
Ogre::SceneNode *	getRootSceneNode ()
Storage *	getStorage ()
void	setVisible (bool visible)
bool	getVisible ()
void	applyMaterials (bool shadows, bool splitShadows)
int	getVisiblityFlags ()
int	getMaxBatchSize ()
void	enableSplattingShader (bool enabled)
Ogre::HardwareIndexBufferSharedPtr	getIndexBuffer (int flags, size_t &numIndices)
Ogre::HardwareVertexBufferSharedPtr	getVertexBuffer (int numVertsOneSide)
Ogre::SceneManager *	getCompositeMapSceneManager ()
void	clearCompositeMapSceneManager ()
void	renderCompositeMap (Ogre::TexturePtr target)
Private Member Functions
void	buildQuadTree (QuadTreeNode *node)
Private Attributes
bool	mDistantLand
bool	mShaders
bool	mShadows
bool	mSplitShadows
bool	mVisible
Loading::Listener *	mLoadingListener
QuadTreeNode *	mRootNode
Ogre::SceneNode *	mRootSceneNode
Storage *	mStorage
int	mVisibilityFlags
Ogre::SceneManager *	mSceneMgr
Ogre::SceneManager *	mCompositeMapSceneMgr
Ogre::AxisAlignedBox	mBounds
	Bounds in cell units.
float	mMinBatchSize
	Minimum size of a terrain batch along one side (in cell units)
float	mMaxBatchSize
	Maximum size of a terrain batch along one side (in cell units)
std::map< int, Ogre::HardwareIndexBufferSharedPtr >	mIndexBufferMap
std::map< int, Ogre::HardwareVertexBufferSharedPtr >	mUvBufferMap
Ogre::RenderTarget *	mCompositeMapRenderTarget
Ogre::TexturePtr	mCompositeMapRenderTexture

Detailed Description

A quadtree-based terrain implementation suitable for large data sets.
Near cells are rendered with alpha splatting, distant cells are merged together in batches and have their layers pre-rendered onto a composite map.
Cracks at LOD transitions are avoided using stitching.

Note:: Multiple cameras are not supported yet

Member Enumeration Documentation

enum Terrain::World::IndexBufferFlags

Enumerator:

IBF_North
IBF_East
IBF_South
IBF_West

Constructor & Destructor Documentation

Terrain::World::World	(	Loading::Listener *	loadingListener,
		Ogre::SceneManager *	sceneMgr,
		Storage *	storage,
		int	visiblityFlags,
		bool	distantLand,
		bool	shaders
	)

Note:: takes ownership of storage

Parameters:

loadingListener	Listener to update with progress
sceneMgr	scene manager to use
storage	Storage instance to get terrain data from (heights, normals, colors, textures..)
visbilityFlags	visibility flags for the created meshes
distantLand	Whether to draw all of the terrain, or only a 3x3 grid around the camera. This is a temporary option until it can be streamlined.
shaders	Whether to use splatting shader, or multi-pass fixed function splatting. Shader is usually faster so this is just here for compatibility.

Terrain::World::~World ( )

Member Function Documentation

void Terrain::World::applyMaterials	(	bool	shadows,
		bool	splitShadows
	)

Recreate materials used by terrain chunks. This should be called whenever settings of the material factory are changed. (Relying on the factory to update those materials is not enough, since turning a feature on/off can change the number of texture units available for layer/blend textures, and to properly respond to this we may need to change the structure of the material, such as adding or removing passes. This can only be achieved by a full rebuild.)

void Terrain::World::buildQuadTree ( QuadTreeNode * node ) [private]

void Terrain::World::clearCompositeMapSceneManager ( )

void Terrain::World::enableSplattingShader ( bool enabled )

Ogre::SceneManager* Terrain::World::getCompositeMapSceneManager ( ) [inline]

bool Terrain::World::getDistantLandEnabled ( ) [inline]

float Terrain::World::getHeightAt ( const Ogre::Vector3 & worldPos )

Ogre::HardwareIndexBufferSharedPtr Terrain::World::getIndexBuffer	(	int	flags,
		size_t &	numIndices
	)

Parameters:

flags	first 4*4 bits are LOD deltas on each edge, respectively (4 bits each) next 4 bits are LOD level of the index buffer (LOD 0 = don't omit any vertices)
numIndices	number of indices that were used will be written here

int Terrain::World::getMaxBatchSize ( ) [inline]

Ogre::SceneNode* Terrain::World::getRootSceneNode ( ) [inline]

Ogre::SceneManager* Terrain::World::getSceneManager ( ) [inline]

bool Terrain::World::getShadersEnabled ( ) [inline]

bool Terrain::World::getShadowsEnabled ( ) [inline]

bool Terrain::World::getSplitShadowsEnabled ( ) [inline]

Storage* Terrain::World::getStorage ( ) [inline]

Ogre::HardwareVertexBufferSharedPtr Terrain::World::getVertexBuffer ( int numVertsOneSide )

bool Terrain::World::getVisible ( )

int Terrain::World::getVisiblityFlags ( ) [inline]

Ogre::AxisAlignedBox Terrain::World::getWorldBoundingBox ( const Ogre::Vector2 & center )

Get the world bounding box of a chunk of terrain centered at center.

void Terrain::World::renderCompositeMap ( Ogre::TexturePtr target )

void Terrain::World::setLoadingListener ( Loading::Listener * loadingListener ) [inline]

void Terrain::World::setVisible ( bool visible )

Show or hide the whole terrain

Note:: this setting will be invalidated once you call Terrain::update, so do not call it while the terrain should be hidden

void Terrain::World::update ( const Ogre::Vector3 & cameraPos )

Update chunk LODs according to this camera position

Note:: Calling this method might lead to composite textures being rendered, so it is best not to call it when render commands are still queued, since that would cause a flush.