Graph Class Reference

This class stores a graph of quads. More...

#include <graph.hpp>

Inheritance diagram for Graph:

Public Member Functions
void	createDebugMesh ()
	Creates the debug mesh to display the graph on top of the track model.
RenderTarget *	makeMiniMap (const core::dimension2du &dimension, const std::string &name, const video::SColor &fill_color, bool invert_x_z)
	Takes a snapshot of the graph so they can be used as minimap.
void	mapPoint2MiniMap (const Vec3 &xyz, Vec3 *out) const
	Returns the 2d coordinates of a point when drawn on the mini map texture.
Quad *	getQuad (unsigned int i) const
unsigned int	getNumNodes () const
void	findRoadSector (const Vec3 &XYZ, int *sector, std::vector< int > *all_sectors=NULL, bool ignore_vertical=false) const
	findRoadSector returns in which sector on the road the position xyz is.
int	findOutOfRoadSector (const Vec3 &xyz, const int curr_sector=UNKNOWN_SECTOR, std::vector< int > *all_sectors=NULL, bool ignore_vertical=false) const
	findOutOfRoadSector finds the sector where XYZ is, but as it name implies, it is more accurate for the outside of the track than the inside, and for STK's needs the accuracy on top of the track is unacceptable; but if this was a 2D function, the accuracy for out of road sectors would be perfect.
const Vec3 &	getBBMin () const
const Vec3 &	getBBMax () const
const int *	getBBNodes () const

Static Public Member Functions
static Graph *	get ()
	Returns the one instance of this object.
static void	setGraph (Graph *graph)
	Set the graph (either drive or arena graph for now).
static void	destroy ()
	Cleans up the graph.

Static Public Attributes
static const int	UNKNOWN_SECTOR = -1
static const float	MIN_HEIGHT_TESTING = -1.0f
static const float	MAX_HEIGHT_TESTING = 5.0f

Protected Member Functions
void	createQuad (const Vec3 &p0, const Vec3 &p1, const Vec3 &p2, const Vec3 &p3, unsigned int node_index, bool invisible, bool ai_ignore, bool is_arena, bool ignore)
	Factory method to dynamic create 2d / 3d quad for drive and arena graph.
void	loadBoundingBoxNodes ()
	Map 4 bounding box points to 4 closest graph nodes.

Protected Attributes
std::vector< Quad * >	m_all_nodes

Static Protected Attributes
static Graph *	m_graph = NULL

Private Member Functions
void	createMesh (bool show_invisible=true, bool enable_transparency=false, const video::SColor *track_color=NULL, bool invert_x_z=false, bool flatten=false)
	Creates the actual mesh that is used by createDebugMesh() or makeMiniMap()
void	createMeshSP (bool show_invisible=true, bool enable_transparency=false, const video::SColor *track_color=NULL, bool invert_x_z=false)
	Creates the actual mesh that is used by createDebugMesh() or makeMiniMap()
void	cleanupDebugMesh ()
	Cleans up the debug mesh.
virtual bool	hasLapLine () const =0
virtual void	differentNodeColor (int n, video::SColor *c) const =0

Private Attributes
Vec3	m_bb_min
	The 2d bounding box, used for hashing.
Vec3	m_bb_max
int	m_bb_nodes [4]
	The 4 closest graph nodes to the bounding box.
scene::ISceneNode *	m_node
	The node of the graph mesh.
scene::IMesh *	m_mesh
	The mesh of the graph mesh.
scene::IMeshBuffer *	m_mesh_buffer
	The actual mesh buffer storing the graph.
float	m_scaling
	Scaling for mini map.
std::unique_ptr< RenderTarget >	m_render_target
	The render target used for drawing the minimap.

Detailed Description

This class stores a graph of quads.

It uses a 'simplified singleton' design pattern: it has a static create function to create exactly instance, a destroy function, and a get function (that does not have the side effect of the 'normal singleton' design pattern to create an instance). Besides saving on the if statement in get(), this is necessary since certain race modes might not have a quad graph at all (e.g. arena without navmesh). So get() returns NULL in this case, and this is tested where necessary.

Member Function Documentation

destroy()

static void Graph::destroy ( )

inlinestatic

Cleans up the graph.

It is possible that this function is called even if no instance exists (e.g. arena without navmesh). So it is not an error if there is no instance.

findOutOfRoadSector()

int Graph::findOutOfRoadSector	(	const Vec3 &	xyz,
		const int	curr_sector = UNKNOWN_SECTOR,
		std::vector< int > *	all_sectors = NULL,
		bool	ignore_vertical = false
	)		const

findOutOfRoadSector finds the sector where XYZ is, but as it name implies, it is more accurate for the outside of the track than the inside, and for STK's needs the accuracy on top of the track is unacceptable; but if this was a 2D function, the accuracy for out of road sectors would be perfect.

To find the sector we look for the closest line segment from the right and left drivelines, and the number of that segment will be the sector.

The SIDE argument is used to speed up the function only; if we know that XYZ is on the left or right side of the track, we know that the closest driveline must be the one that matches that condition. In reality, the side used in STK is the one from the previous frame, but in order to move from one side to another a point would go through the middle, that is handled by findRoadSector() which doesn't has speed ups based on the side.

NOTE: This method of finding the sector outside of the road is not perfect: if two line segments have a similar altitude (but enough to let a kart get through) and they are very close on a 2D system, if a kart is on the air it could be closer to the top line segment even if it is supposed to be on the sector of the lower line segment. Probably the best solution would be to construct a quad that reaches until the next higher overlapping line segment, and find the closest one to XYZ.

findRoadSector()

void Graph::findRoadSector	(	const Vec3 &	xyz,
		int *	sector,
		std::vector< int > *	all_sectors = NULL,
		bool	ignore_vertical = false
	)		const

findRoadSector returns in which sector on the road the position xyz is.

If xyz is not on top of the road, it sets UNKNOWN_SECTOR as sector.

Parameters

xyz	Position for which the segment should be determined.
sector	Contains the previous sector (as a shortcut, since usually the sector is the same as the last one), and on return the result
all_sectors	If this is not NULL, it is a list of all sectors to test. This is used by the AI to make sure that it ends up on the selected way in case of a branch, and also to make sure that it doesn't skip e.g. a loop (see explanation below for details).

get()

static Graph * Graph::get ( )

inlinestatic

Returns the one instance of this object.

It is possible that there is no instance created (e.g. arena without navmesh) so we don't assert that an instance exist.

mapPoint2MiniMap()

void Graph::mapPoint2MiniMap	(	const Vec3 &	xyz,
		Vec3 *	draw_at
	)		const

Returns the 2d coordinates of a point when drawn on the mini map texture.

Parameters

xyz	Coordinates of the point to map.
draw_at	The coordinates in pixel on the mini map of the point, only the first two coordinates will be used.

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The documentation for this class was generated from the following files:

• tracks/graph.hpp
• tracks/graph.cpp