ARLib::Application::ARAppBase Class Reference

The ARAppBase class defines default functionality for the ARApplication class. More...

#include <arappbase.h>

List of all members.

Public Types
enum	IncrementModes { INCREMENT_MODE_ZOOM = 0, INCREMENT_MODE_PARAM = 1, INCREMENT_MODE_DISPLAY = 2 }
	Values denoting the current operation of the +/- keys e.g zoom, paramater update or element display. More...
Public Member Functions
virtual void	OnInit (int *argc, char *argv[])
	Called when application is first started.
virtual void	OnKeyPress (unsigned int state, unsigned int key, int x, int y, bool &actioned)
	Called when a key is pressed.
virtual void	OnEraseBackground ()
	Called when the background needs clearing.
virtual void	OnUpdate ()
	Called when the OpenGL window needs repainting.
virtual void	OnPostUpdate ()
	Called after update but before OpenGL buffer is displayed on the screen.
virtual void	OnResize (int width, int height)
	Called when the window has been resized.
virtual void	OnDisplayMessage (const char *message)
	Called when the passed message text should be displayed on the screen.
virtual void	OnDisplayUpdateModeValue (unsigned int id, const Utility::ARString &name)
	Called when the Update Mode parameter values needs displaying.
virtual void	OnDisplayDisplayModeValue (bool *value, const Utility::ARString &name)
	Called when the Display mode value needs to be displayed.
virtual void	OnIncrementUpdateModeValue (unsigned int id, int increment)
	Called when a particular update mode value needs updating.
virtual void	OnDisplayFPS (unsigned int fps)
	Called when the frames per second needs to be displayed.
virtual void	OnDisplayFrameNo (unsigned int frameNo)
	Called then the current frame number needs to be displayed.
virtual void	OnDisplayFocalLength (int FocalLengthU, int FocalLengthV)
	Called when the focal length values need to be displayed.
virtual void	OnDisplayMarkerEdge (Detection::ARBoundingBox *marker, Graphics::ARImage *image)
	Called when the edge around the detected marker needs to be drawn.
virtual void	OnDisplayMarkerBox (Detection::ARBoundingBox *marker, Graphics::ARImage *image)
	Called when the bounding box needs to be drawn around the detected marker.
virtual void	OnDisplayMarkerCorners (Detection::ARBoundingBox *marker, Graphics::ARImage *image)
	Called when the current marker corners need to be drawn.
virtual void	OnDisplayMarkerId (Detection::ARBoundingBox *marker, Graphics::ARImage *image)
	Called when the current marker Id needs to be drawn.
virtual void	OnDisplayAR (Detection::ARBoundingBox *marker)
	Called when the OpenGL object needs to be displayed for the current detected marker.
virtual void	OnInitDisplayAR ()
	Called prior to displaying augmented objects.
virtual void	OnSetMarkerPose (Detection::ARBoundingBox *marker)
	Called when the OpenGL projection and modelview matrices need to be set.
virtual void	OnSegmentImage (Graphics::ARImage *image)
	Called when the current frame image needs to be segmented.
virtual void	OnGetApplicationTitle (Utility::ARString &title)
	Called to retrive the title for the application.
virtual void	OnGetDetailHelp (Utility::ARString &help)
	Called when detailed help text is needed for the current application.
virtual void	OnInitHelp ()
	Called when help keys and command line switches should be defined.
void	AddHelpSwitch (const Utility::ARString &Switch, const Utility::ARString &Description)
	Method for adding help for a particular command line switch.
void	AddHelpKey (const Utility::ARString &Key, const Utility::ARString &Description)
	Method for adding help for a particular user key switch.
void	Update ()
	Call this method to repaint screen.
int	GetWinWidth ()
	Returns the width of the current window.
Utility::ARRecti	GetWinRect ()
	Returns the window rectangle.
int	GetWinHeight ()
	Returns the height of the current window.
int	GetZoom ()
	Returns the zoom factor for the current viewport.
Graphics::ARImage *	GetImage ()
	Returns a pointer to the current image.
int	GetMode ()
	Returns the current mode of operation (e.g. video streaming or static images).
int	GetChannel ()
	Returns the current image channel/s that are being displayed.
Detection::ARMarkers *	GetMarkers ()
	Returns the current marker definitions.
Utility::ARConfiguration *	GetConfig ()
	Returns a pointer to the current configuration data.
bool	GetConfigValue (const char *section, const char *item, Utility::ARString &value, const char *defvalue=0)
	Retrieves the value associated with the section/item combination from the configuration file.
bool	GetConfigValues (const char *section, const char *item, std::vector< Utility::ARString > &values, const char *defvalue=0)
	Retrieves multiple values associated with the section/item combination from the configuration file.
int	GetActualFPS ()
	Returns the actual frames per second being processed.
int	GetFrameNo ()
	Returns the current frame number.
void	AddUpdateMode (unsigned int id, const Utility::ARString &name)
	Adds an updateable parameter to the current list.
bool	NextUpdateMode (bool forwards=true)
	Cycles through the available parameter update modes.
void	AddDisplayMode (bool *value, const Utility::ARString &name)
	Adds an element that can be turned on or off.
bool	NextDisplayMode (bool forwards=true)
	Cycles through the available element display modes.
void	DrawBuffer (int x, int y, const char *buffer, const Graphics::ARColour &colour, void *font=GLUT_BITMAP_HELVETICA_18)
	Draws text to the current window.
void	DrawBuffer (Utility::ARRecti rect, const char *buffer, int flags, Graphics::ARColour colour, void *font=GLUT_BITMAP_HELVETICA_18)
	Draws text to the current window.
void	SetTimedMessage (const char *message)
	This method will display a message on the screen for a fixed duration.
int	GetMarkerCount ()
	Returns the number of detected markers in the current frame.
Protected Member Functions
bool	GetSnapshotFilename (Utility::ARString &filename)
	Returns the next available snapshot filename.
Protected Attributes
int	markerCount
	The number of currently detected markers.
std::vector< ARUpdateMode >	updateModes
	The _updateModes vector stores the various update modes that the user can cycle through.
int	updateModeIdx
	Holds the index position of the current Update Parameters mode item.
std::vector< ARDisplayMode >	displayModes
	The _displayModes vector stores the various element visibility modes that the user can cycle through.
int	displayModeIdx
	Holds the index position of the current Element visibility mode item.
unsigned int	incrementMode
	Denotes the current operation for the arrow keys. The value can be one of the IncrementModes enumeration.
int	zoom
	Denotes the zoom level of the current view.
bool	showUI
	Overide for the displaying of UI elements.
bool	showFPS
	Denotes whether the frames per second should be displayed.
bool	showFrameNo
	Denotes whether the current frame number should be displayed.
bool	showFocalLength
	Denotes whether the current frame focal length should be displayed.
bool	showBoundingBoxes
	Denotes whether bounding boxes should be drawn around potential marker regions.
bool	showCorners
	Denotes whether corners of potential markers should be displayed.
bool	showMarkerEdge
	Denotes whether a line should be draw around the detected marker.
bool	showMarkerId
	Denotes whether the marker id should be displayed against the detected marker.
bool	showAR
	Denotes whether the augmented elemented should be displayed.
int	channel
	Denotes the current colour channel being display. The value can be one of the Channel enumeration.
int	otsuOffset
	Denotes the amount the dynamic Otsu threshold value should be adjusted by.
bool	useLuminance
unsigned int	minArea
	Denotes the number of pixels that a bounding box must be to be deemed valid.
int	fixedFocalLengthU
	Denotes the fixed focal length in the U direction.
int	fixedFocalLengthV
	Denotes the fixed focal length in the V direction.
int	currentFocalLengthU
	Denotes the current focal length in the U direction.
int	currentFocalLengthV
	Denotes the current focal length in the V direction.
bool	useFixedFocalLength
	Denotes whether to use fixed focal lengths or dyanamically calculate them based on marker position.
Detection::ARDetection	detection
	The main marker detection object.
Utility::ARString	defaultModelsConfigPath
	The default path to the models.conf file.
Utility::ARConfiguration	modelsConfig
	The models configuration data.
Utility::ARString	timedMessage
	Message to display for a short time.
Utility::ARPoint3Di	rotation
	Specifies the default rotation of each object prior to being displayed.
bool	takeSnapshot
	Denotes whether a snaphot tiff file should be saved after the next frame is rendered.
Utility::ARString	snapshotLocation
	Defines the folder to write snapshots to.
Utility::ARString	snapshotPrefix
	Defines the prefix to use when writing out snapshots. The final file name will be <snapshotprefix>.n.tif.

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Detailed Description

The ARAppBase class defines default functionality for the ARApplication class.

To create custom application functionality, a new class should be created which is derived from the ARAppBase class.

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Member Enumeration Documentation

enum ARLib::Application::ARAppBase::IncrementModes

Values denoting the current operation of the +/- keys e.g zoom, paramater update or element display. Enumeration values: INCREMENT_MODE_ZOOM  = (0) Updates zoom. INCREMENT_MODE_PARAM  = (0) Updates configuration parameters. INCREMENT_MODE_DISPLAY  = (0) Turning element visibility on or off.

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Member Function Documentation

void ARAppBase::AddDisplayMode (  bool *  value, const Utility::ARString &  name )

Adds an element that can be turned on or off. Update modes can be cycled using the relevant key. The +/- keys can then be used to turn the element on or off e.g. turn on/off the showing of fps. Parameters: value  A pointer to the associated boolean value. name  A name to display for the parameter.

void ARAppBase::AddHelpKey (  const Utility::ARString &  Key, const Utility::ARString &  Description )

Method for adding help for a particular user key switch. Parameters: Key  The key e.g. "F1". Description  The description of the key e.g. "Displays help."

void ARAppBase::AddHelpSwitch (  const Utility::ARString &  Switch, const Utility::ARString &  Description )

Method for adding help for a particular command line switch. Parameters: Switch  The switch e.g. "filename <name>". Description  The description of the switch e.g. "Load the specified <name>."

void ARLib::Application::ARAppBase::AddUpdateMode (  unsigned int  id, const Utility::ARString &  name )

Adds an updateable parameter to the current list. Updateable parameters can be cycled using the relevant key. The +/- keys can then be used to increment or decrement the associated value. Parameters: id  A unique identifier for the parameter. name  A name to display for the parameter.

void ARLib::Application::ARAppBase::DrawBuffer (  Utility::ARRecti  rect, const char *  buffer, int  flags, Graphics::ARColour  colour, void *  font = GLUT_BITMAP_HELVETICA_18 )

Draws text to the current window. Parameters: rect  The bounding rectangle for the text. buffer  A null terminated char buffer. flags  Denotes how to justify the text with the rectangle. This is a bitmask value and acceptible values from from the DrawBufferFlags enumeration. colour  The colour of the text. font  The font to use. The fonts are defined by the Glut library (Refer to Glut documentation (glutBitmapCharacter) for available fonts.

void ARLib::Application::ARAppBase::DrawBuffer (  int  x, int  y, const char *  buffer, const Graphics::ARColour &  colour, void *  font = GLUT_BITMAP_HELVETICA_18 )

Draws text to the current window. Parameters: x  The column coordinate for the first character. y  The row coordinate for the first character. buffer  A null terminated char buffer. colour  The colour of the text. font  The font to use. The fonts are defined by the Glut library (Refer to Glut documentation (glutBitmapCharacter) for available fonts.

int ARAppBase::GetActualFPS (   )

Returns the actual frames per second being processed. Returns: An integer representing the number of frames being processed per second.

int ARLib::Application::ARAppBase::GetChannel (   )

Returns the current image channel/s that are being displayed. Returns: A value from the Channel enumeration.

bool ARAppBase::GetConfigValue (  const char *  section, const char *  item, Utility::ARString &  value, const char *  defvalue = 0 )

Retrieves the value associated with the section/item combination from the configuration file. Parameters: section  The section that the item belongs to. item  The item name to retrieve the value for. value  The ARString argument to receive the associated value; defvalue  The value to use if the section/item does not exist. Returns: True if the section/item exists otherwise false.

bool ARLib::Application::ARAppBase::GetConfigValues (  const char *  section, const char *  item, std::vector< Utility::ARString > &  values, const char *  defvalue = 0 )

Retrieves multiple values associated with the section/item combination from the configuration file. Parameters: section  The section that the item belongs to. item  The item name to retrieve the value for. values  The ARString vector argument to receive the associated values; defvalue  The value to use if the section/item does not exist. Returns: True if the section/item exists otherwise false.

int ARAppBase::GetFrameNo (   )

Returns the current frame number. Returns: An Integer value representing the frame number.

ARImage * ARAppBase::GetImage (   )

Returns a pointer to the current image. Returns: An integer value containing the zoom factor. A value of 1 is normal 1 to 1 mapping, 2 is twice normal size and so on.

ARMarkers * ARAppBase::GetMarkers (   )

Returns the current marker definitions. Returns: A Pointer to the current ARMarkers object.

int ARAppBase::GetMode (   )

Returns the current mode of operation (e.g. video streaming or static images). Returns: A value from the Mode enumeration.

bool ARLib::Application::ARAppBase::GetSnapshotFilename (  Utility::ARString &  filename  )  [protected]

Returns the next available snapshot filename. Parameters: filename  Parameter to return the filename in. Returns: True if successful other false is returned.

int ARAppBase::GetWinHeight (   )

Returns the height of the current window. Returns: An integer value containing the height in pixels of the window.

Utility::ARRecti ARLib::Application::ARAppBase::GetWinRect (   )  [inline]

Returns the window rectangle. Returns: A RECT type containing the window coordinates.

int ARAppBase::GetWinWidth (   )

Returns the width of the current window. Returns: An integer value containing the width in pixels of the window.

int ARLib::Application::ARAppBase::GetZoom (   )  [inline]

Returns the zoom factor for the current viewport. Returns: An integer value containing the zoom factor. A value of 1 is normal 1 to 1 mapping, 2 is twice normal size and so on.

bool ARAppBase::NextDisplayMode (  bool  forwards = true  )

Cycles through the available element display modes. Display modes allow visual aspects to be turned on or off using the +/- keys. Parameters: forwards  Specify true to move forwards or false to move backwards. Returns: false if there are no modes to cycle through.

bool ARAppBase::NextUpdateMode (  bool  forwards = true  )

Cycles through the available parameter update modes. Update modes allow specific configuration options to be updated using the +/- keys. Parameters: forwards  Specify true to move forwards or false to move backwards. Returns: false if there are no modes to cycle through.

void ARAppBase::OnDisplayDisplayModeValue (  bool *  value, const Utility::ARString &  name )  [virtual]

Called when the Display mode value needs to be displayed. The function should display the name and the value so that when using the +/- keys, the user can see the new value. Parameters: value  Pointer to the current boolean value. name  The name to display with the value.

void ARAppBase::OnDisplayFocalLength (  int  FocalLengthU, int  FocalLengthV )  [virtual]

Called when the focal length values need to be displayed. Parameters: FocalLengthU  The current U direction focal length. FocalLengthV  The current V direction focal length.

void ARAppBase::OnDisplayFPS (  unsigned int  fps  )  [virtual]

Called when the frames per second needs to be displayed. Parameters: fps  The current frames per second.

void ARAppBase::OnDisplayFrameNo (  unsigned int  frameNo  )  [virtual]

Called then the current frame number needs to be displayed. Parameters: frameNo  The current frame number.

virtual void ARLib::Application::ARAppBase::OnDisplayMarkerBox (  Detection::ARBoundingBox *  marker, Graphics::ARImage *  image )  [virtual]

Called when the bounding box needs to be drawn around the detected marker. Parameters: marker  The ARBoundingBox marker object containing all the current marker information. image  The image to perform drawing operation on.

virtual void ARLib::Application::ARAppBase::OnDisplayMarkerCorners (  Detection::ARBoundingBox *  marker, Graphics::ARImage *  image )  [virtual]

Called when the current marker corners need to be drawn. The default behaviour draws a small cross at each corner of the marker. Parameters: marker  The ARBoundingBox marker object containing all the current marker information. image  The image to perform drawing operation on.

virtual void ARLib::Application::ARAppBase::OnDisplayMarkerEdge (  Detection::ARBoundingBox *  marker, Graphics::ARImage *  image )  [virtual]

Called when the edge around the detected marker needs to be drawn. The default behaviour of this method is to draw a line between each of the corners. Parameters: marker  The ARBoundingBox marker object containing all the current marker information. image  The image to perform drawing operation on.

virtual void ARLib::Application::ARAppBase::OnDisplayMarkerId (  Detection::ARBoundingBox *  marker, Graphics::ARImage *  image )  [virtual]

Called when the current marker Id needs to be drawn. Parameters: marker  The ARBoundingBox marker object containing all the current marker information. image  The image to perform drawing operation on.

void ARAppBase::OnDisplayMessage (  const char *  message  )  [virtual]

Called when the passed message text should be displayed on the screen. It is upto the custom implementation to determine how or where the message is displayed. The function is called when a timed message is to be displayed. Parameters: message  The string to display.

virtual void ARLib::Application::ARAppBase::OnDisplayUpdateModeValue (  unsigned int  id, const Utility::ARString &  name )  [virtual]

Called when the Update Mode parameter values needs displaying. The display should show the name and value so that when using the +/- keys, the user can see the new value. Parameters: id  The unique identifier for the current update mode. name  The name of the parameter.

void ARAppBase::OnGetApplicationTitle (  Utility::ARString &  title  )  [virtual]

Called to retrive the title for the application. Parameters: title  The ARString object to return the title text in.

void ARAppBase::OnGetDetailHelp (  Utility::ARString &  help  )  [virtual]

Called when detailed help text is needed for the current application. Parameters: help  The ARString object to return the help text in.

void ARAppBase::OnIncrementUpdateModeValue (  unsigned int  id, int  increment )  [virtual]

Called when a particular update mode value needs updating. /param id The unique identifier for the current update mode. /param increment The amount (positive or negative) by which the value should be incremented.

void ARAppBase::OnInit (  int *  argc, char *  argv[] )  [virtual]

Called when application is first started. Enables the custom functionality to initialise itself and to process any custom command line switches. Parameters: argc  Number of arguments. argv  Pointer to an array of switch values.

void ARAppBase::OnInitDisplayAR (   )  [virtual]

Called prior to displaying augmented objects. This function enables OpenGL parameters (e.g. lights, setup buffers, etc) to be set prior to displaying each AR element. The default behavior of this function sets up the OpenGL depth buffer and creates the viewport for the AR.

void ARAppBase::OnInitHelp (   )  [virtual]

Called when help keys and command line switches should be defined. The methods AddHelpSwitch and AddHelpKey should be called to load the availables command line switches and user keys.

void ARAppBase::OnKeyPress (  unsigned int  state, unsigned int  key, int  x, int  y, bool &  actioned )  [virtual]

Called when a key is pressed. Parameters: state  A bitmask value denoting various states of the keyboard. key  The ascii value of the key x  The mouse x coordinate when the key was pressed. y  The mouse y coordinate when the key was pressed. actioned  If the key is processed in the OnKeyPress function then the actioned parameter should be set to True so the application performs no further actions. The following code demonstrates decoding the state value if (state & KEY_EXTENDED) std::cout << "Extended "; if (state & KEY_SHIFT) std::cout << "Shift "; if (state & KEY_ALT) std::cout << "Alt "; if (state & KEY_CTRL) std::cout << "Ctrl "; If the extended bit is set then the key value is one of the special glut key values e.g. GLUT_KEY_F1,GLUT_KEY_F2, GLUT_KEY_LEFT etc. Refer to Glut documentation for a complete list of special constants (glutSpecialFunc).

void ARAppBase::OnResize (  int  width, int  height )  [virtual]

Called when the window has been resized. Parameters: width  The new width of the window height  The new height of the window

virtual void ARLib::Application::ARAppBase::OnSegmentImage (  Graphics::ARImage *  image  )  [virtual]

Called when the current frame image needs to be segmented. This function should update the alpha channel of the image so that there are only black (0) and white (255) values. The default implementation of this function performs Otsu dynamic thresholding. Parameters: image  The current image to modify the alpha channel.

void ARAppBase::OnSetMarkerPose (  Detection::ARBoundingBox *  marker  )  [virtual]

Called when the OpenGL projection and modelview matrices need to be set. Parameters: marker  The ARBoundingBox marker object containing all the current marker information.

void ARAppBase::SetTimedMessage (  const char *  message  )

This method will display a message on the screen for a fixed duration. Parameters: message  The message to display.

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Member Data Documentation

bool ARLib::Application::ARAppBase::showUI [protected]

Overide for the displaying of UI elements. If this value is false then no elements will be shown (regardless of their own show flag)

bool ARLib::Application::ARAppBase::useLuminance [protected]

Denotes whether the black and white segmentation should use a luminance formula or a simple average of the red, green and blue component values.

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

• arappbase.h
• arappbase.cpp

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