Introduction to Object

Introduction to Object/Property/Event Architecture

Capabilities

1. Treat most WTK object types as generic (or base) objects, which can be stroed, manipulated, and retrived in a uniform manner using certain WTbase functions.

2. Create you own properties for objects. in which to easily store user-defined data. This provides a convenient alternative to the setdata and getdata functions for each object type.

3. Trigger reactions to property changes for both user-defined properties and pre-defined properties. A property change is known as an event, and the optional reaction that is triggered in response to an event is controlled by the property's event handles(s)

4. Share properties, allowing you to create multi-user simulations to be used with World2World.

Advantages of OPE Architecture

1. Easier to create user-defined data with objects

2. The event-basse architecture corresponds more closely with other modern event-based programming paradigms

3. Easy integration with World2World.

Object Types Supported by OPE Architecture

WTnode
WTviewpoint
WTwindow
WTsensor
WTpath
WTbase

Properties

Objects supported by the OPE architecture are distinguished from one another by their properties.

Properties describe characteristics of an object.

Additional user-defined properties can be added to an object of any of the supported types.

Events occur when a property is set (even if it is set to the same value it had previously)

Properties are specified by their porperty name. Each property MUST have a unique name

Each property is of a specified data type.

The following table lists the predefined WTK data types and their actual C data type.

WTdatatype Actual Data Type

WTINT int

WTUINT unsigned int

WTFLOAT float

WTDOUBLE double

WTP2 float[2]

WTP3 float[3]

WTQ float[4]

WTSTRING char *

WTPOINTER void *

The following tables lists the perdefined properties of the WTK OPE supported data types (WTnode, WTviewpoint, WTwindow, WTsensor, WTpath, and WTbase).

WTanchornode Properties Data Type Description

WTANCHOR_LOCATION WTSTRING

WTfognode Properties Data Type Description

WTFOG_COLOR WTQ (R,G,B,A)

WTFOG_LINEARSTART WTFLOAT

WTFOG_MODE WTINT

WTFOG_RANGE WTFLOAT

WTinlinenode Properties Data Type Description

WTINLINE_LOCATION WTSTRING

WTlightnode Properties Data Type Description

WTLIGHT_AMBIENT WTP3 Ambient Color (R,G,B)

WTLIGHT_ANGLE WTFLOAT

WTLIGHT_ATTENUATION WTP3

WTLIGHT_DIFFUSE WTP3 Diffuse Color (R,G,B)

WTLIGHT_DIRECTION WTP3 Direction Vector (normalized)

WTLIGHT_EXPONENT WTFLOAT

WTLIGHT_INTENSITY WTFLOAT Intensity of the light

WTLIGHT_POSITION WTP3 Position of the light

WTLIGHT_SPECULAR WTP3 Specular color of the light

WTlodnode Properties Data Type Description

WTLOD_CENTER WTP3

WTLOD_RANGE WTSTRING ("range;range;range")

WTmovnode Properties Data Type Description

WTMOVNODE_ATTACHMENTS WTSTRING ("name,name,name") list of the name of the attached nodes

WTnode Properties Data Type Description

WTNODE_BOUNDINGBOX WTINT Bounding box ON or OFF

WTNODE_CHILDREN WTSTRING (name;name;name) List of the names of the child nodes

WTNODE_ENABLED WTINT Is the node ON or OFF

WTNODE_ROTATION WTQ The rotation of the node in parent frame

WTNODE_TRANSLATION WTP3 The translation of the node in parent frame

WTsepnode Properties Data Type Description

WTSEP_CULLMODE WTINT Culling ON or OFF

WTswitchnode Properties Data Type Description

WTSWITCH_WHICHCHILD WTINT The current active child of the switch

WTviewpoint Properties Data Type Description

WTVIEWPOINT_ASPECT WTFLOAT

WTVIEWPOINT_CONVDISTANCE WTFLOAT Convergence Distance

WTVIEWPOINT_CONVERGENCE WTINT

WTVIEWPOINT_ORIENTATION WTQ The orientation of the viewpoint

WTVIEWPOINT_PARALLAX WTFLOAT

WTVIEWPOINT_POSITION WTP3 The position of the viewpoint

WTwindow Properties Data Type Description

WTWINDOW_BGRGB WTP3 Window background color

WTWINDOW_BOTTOMRIGHT WTP2 Bottom right coroner of the window

WTWINDOW_ENABLED WTNT Window ON or OFF

WTWINDOW_EYE WTINT The eye (left or right) the window is being rendered from

WTWINDOW_HITHER WTFLOAT Position of hither clipping plane

WTWINDOW_KEY WTINT ASCII value of a key press when window has focus

WTWINDOW_LBUTTON WTINT Left mouse button clicked in window

WTWINDOW_LBUTTONDBLCLICK WTINT Left mouse button double clicked in the window

WTWINDOW_RBUTTON WTINT Right mouse button clicked in window

WTWINDOW_RBUTTONDBLCLICK WTINT Right mouse button double clicked in window

WTWINDOW_MBUTTON WTINT Middle mouse button clicked in window

WTWINDOW_MBUTTONDBLCLICK WTINT Middle mouse button dowble clicked in the window

WTWINDOW_POSITION WTPT Position of the window

WTWINDOW_PROJECTION WTINT Projection type

WTWINDOW_ROOTNODE WTSTRING Name of the root node for this window

WTWINDOW_SIZE WTP2

WTWINDOW_TOPLEFT WTP2 Position of the top left corner of the window

WTWINDOW_VIEWANGLE WTFLOAT The view angle of the window

WTWINDOW_VIEWPOINT WTSTRING The viewpoint in the window

WTWINDOW_VIEWPOINT2 WTSTRING

WTWINDOW_YON WTFLOAT The position of the Yon (far) clipping plane

WTsensor Properties Data Type Description

WTSENSOR_ANGULARRATE WTFLOAT The angular rate of the sensor

WTSENSOR_LASTROTATION WTQ The last (previous) rotation record from the sensor

WTSENSOR_LASTTRANSLATION WTP3 The last (previous) translation record from the sensor

WTSENSOR_MISCDATA WTINT The misc data structure from the sensor

WTSENSOR_RAWDATA WTPOINTER Pointer to the raw data structure for the sensor

WTSENSOR_ROTATION WTQ The current rotation record from the sensor

WTSENSOR_ROTATIONALOFFSET WTQ

WTSENSOR_SENSITIVITY WTFLOAT The sensitivity of the sensor (translational)

WTSENSOR_TRANSLATION WTP3 The current translation record from the sensor

WTSENSOR_UPDATEFN WTPOINTER Pointer to the Update function of the sensor

WTpath Properties Data Type Description

WTPATH_CONSTRAINTS WTINT

WTPATH_DIRECTION WTINT Play direction of the path

WTPATH_MARKER WTPOINTER Pointer to the geometry used as a marker

WTPATH_MODE WTINT Play mode for the path

WTPATH_PLAYING WTINT Play state of the path

WTPATH_PLAYSPEED WTINT Play speed of the path

WTPATH_ROTATION WTQ

WTPATH_RECORDING WTINT Recording state of the path

WTPATH_RECORDLINK WTPOINTER Pointer the the motionlink to use for recording

WTPATH_SAMPLES WTINT

WTPATH_TRANSLATION WTP3

WTPATH_VISIBILITY WTNT

Getting the value of a property

WTK provides 3 ways to obtain the value of a property. One generic fuction, type-specific fucnctions, and "getasstring" function.

Generic Function

SYNTAX:
FLAG WTproperty_get(void *object, const char *propname, void *value);

ARGUMENTS:
object -- A pointer to the object
propname -- a string containing the property name
(void *) value -- a pointer to the varaible that will receive the value of the property. Type casting is necessary.

RETURN TYPE:
FLAG -- returns TRUE if the function was successful.

Example:

        WTviewpoint *vp;
        WTp3 pos;
        vp = WTuniverse_getviewpoints();

        /* get the POSITION property of the viewpoint */
        WTproperty_get(vp, WTVIEWPOINT_POSITION, (void *)pos);

/* print the position */
        WTp3_print(pos , "Position = ");

NOTE:
The char* reusult of retrieving a WTSTRING property value is a pointer to the actual string stored in WTK. DO NOT modify this directly with calls to WTfree, WTrealloc, strcat, strcpy, etc. If you need to modify the string value, make a local copy of the string before modifying it.

Type Specific Functions

Each WTK data type has its own type specific utility function for getting the property value. The able below describes each function.

Function Name WTK data type Syntax Description

WTproperty_geti WTINT int
WTproperty_geti(
void *object,
const char*propname); Returns a property with a WTINT data type.

WTproperty_getui WTUINT unsigned int WTpropert_getui(
void *object,
const char*propname); Retuns a propery with a WTUINT data type.

WTproperty_getf WTFLOAT float
WTpropert_getf(
void *object,
const char*propname); Returns a property with a WTFLOAT data type.

WTproperty_getd WTDOUBLE double
WTpropert_getd(
void *object,
const char*propname); Returns a property with a WTDOUBLE data type.

WTproperty_getp2 WTP2 FLAG
WTpropert_getp2(
void *object,
const char*propname
WTp2 value); Places the value of the property in its value argument.

WTproperty_getp3 WTP3 FLAG
WTpropert_getp3(
void *object,
const char*propname
WTp3 value); Places the value of the property in its value argument.

WTproperty_getq WTQ FLAG
WTpropert_getq(
void *object,
const char*propname
WTQ value); Places the value of the property in its value argument.

WTproperty_gets

WTSTRING char *
WTpropert_getsi(
void *object,
const char*propname); Returns a property with a WTDOUBLE data type.
NOTE:
The char* reusult of retrieving a WTSTRING property value
is a pointer to the actual string stored in WTK. DO NOT modify this directly with calls to WTfree, WTrealloc, strcat, strcpy, etc. If you need to modify the string value, make a local copy of the string before modifying it.

WTproperty_getp WTPOINTER void *
WTpropert_getp(
void *object); Returns the property with a WTPOINTER data type.

WTproperty_getasstring function

Returns the specified objects specified property value as a string. (Strings returned are only good until another call th WTproperty_getasstring is executed.

SYNTAX:
char * WTproperty_getasstring(void *object, const char *propname);

ARGUMENTS:
object -- a pointer to the object in question
propname -- string containing the property name

RETURN TYPE
char * -- The property value as a string.

Assignment 8

project definition:

Creates a universe with a bordered window in monoscopic mode..
Create a cylinder that has a height of 40, a radius of 5, 12 tessellation lines, is single sided and gouraud shaded.
Create a sphere with a radius of 10, 12 lat and long divisions, is single sided, and gouraud shaded.
Create a movable geometry node for the cylinder whose parent is the root node.
Create a movable geometry nodes for the sphere whose parent is the root node.
Create and instance of the movable node containing the sphere as the 2^nd child of the root node
Set the translation of the movable geometry containing the first sphere to (0,-20,0)
Set the translation of the movable geometry containing the second sphere to (0,20,0)
Zooms the view in the window
Create an action function that allows the user to:
- press q to quit
- press p to print the scene graph from the root node. (use WTnode print)
- press i on the keyboard to get the the position of the viewpoint using the WTproperty_get function, and print it to the screen.
- press I on the keyboard to get the position of the viewpoint using the WTproperty_getp3 function, and print it to the screen.
- press S on the keyboard to get the value of the position of th veiepoint using the WTproperty_getasstring function, and print it to the screen.

Setting an objects property value

WTK provides 3 ways to set the value of a property. One generic fuction, type-specific fucnctions, and the WTproperty_setat function.

Generic Function: (WTproperty_set)

WTproperty_set function sets the value of the spercified property for the specified object.

SYNTAX:
FLAG WTproperty_set(void *object, const char *propname, void *value);

ARGUMENTS:
object -- a pointer to the object whose property you want to set
propname -- a string containing the name of the property
value -- the new value NOTE: typcasting of the newvalue is required.

RETURN TYPE:
FLAG is TRUE if the function was successful.

Example: /* translating the viewpoint in world coordinates in the positive X direction*/

        WTp3 vpPos;
        WTviewpoint *vp;
        vp = WTuniverse_getviewpoints();
        WTproperty_getp3(vp, WTVIEWPOINT_POSITION, vpPos);
        vpPos[X] = vpPos[X] + 1.0f;
        WTproperty_set(vp, WTVIEWPOINT_POSITION,(void *)vpPos);

Type Specific Functions

Each WTK data type has its own type specific utility function for setting the property value. The able below describes each function.

Function Name

WTK data type Syntax Description

WTproperty_seti WTINT WTproperty_seti(
void *object,
const char *propname,
int value); Sets specified properties WTINT value

WTproperty_setui WTUINT WTproperty_setui(
void *object,
const char *propname,
unsigned int value); Sets specified properties WTUINT value

WTproperty_setf WTFLOAT WTproperty_setf(
void *object,
const char *propname,
unsigned int value); Sets specified properties WTFLOAT value

WTproperty_setd WTDOUBLE WTproperty_setd(
void *object,
const char *propname,
double value); Sets specified properties WTDOUBLE value

WTproperty_setp2 WTP2 WTproperty_setp2(
void *object,
const char *propname,
WTp2 value); Sets specified properties WTP2 value

WTproperty_setp3 WTP3 WTproperty_setp3(
void *object,
const char *propname,
WTp3 value); Sets specified properties WTP3 value

WTproperty_setq WTQ WTproperty_setq(
void *object,
const char *propname,
WTq value); Sets specified properties WTQ value

WTproperty_sets
WTSTRING WTproperty_setd(
void *object,
const char *propname,
condy vhst *value); Sets specified properties WTSTRING value

WTproperty_setp WTPOINTER WTproperty_setp(
void *object,
const char *propname,
void *value); Sets specified properties WTPOINTER value

WTproperty_setat function

This function sets the specified object's property value at a specified time. Time values are measured in seconds from January 1st, 1970 and includes fractions of a second.

SYNTAX:
FLAG WTproperty_setat(void *object, const char* propname, void *value, double time);

ARGUMENTS:
object -- pointer to the object whose property to set.
propname -- a string value containing the name of the property to set.
value -- pointer to the new value
time -- time to set the property.

RETURN TYPE:
FLAG is TRUE is the function was successful.

Assignment 9

project definition:

Creates a universe with a bordered window in monoscopic mode..
Create a cylinder that has a height of 40, a radius of 5, 12 tessellation lines, is single sided and gouraud shaded.
Create a sphere with a radius of 10, 12 lat and long divisions, is single sided, and gouraud shaded.
Create a movable geometry node for the cylinder whose parent is the root node.
Create a movable geometry nodes for the sphere whose parent is the root node.
Create and instance of the movable node containing the sphere as the 2^nd child of the root node
Set the translation of the movable geometry containing the first sphere to (0,-20,0)
Set the translation of the movable geometry containing the second sphere to (0,20,0)
Zooms the view in the window
Create an action function that allows the user to:
- press q to quit
- press p to print the scene graph from the root node. (use WTnode print)
- press i on the keyboard to get the the position of the viewpoint using the WTproperty_get function, and print it to the screen.
- press I on the keyboard to get the position of the viewpoint using the WTproperty_getp3 function, and print it to the screen.
- press S on the keyboard to get the value of the position of th veiepoint using the WTproperty_getasstring function, and print it to the screen.
- press X on the keyboard to translate the viewpoint one unit in the positive X direction in world coordinates.

Adding user-defined properties to an object

Use the WTproperty_new function to add user-defined properties to an object.

SYNTAX:
FLAG WTproperty_new( void *object, const char* propname, WTdatatype *dtype);

ARGUMENTS:
object -- the object to add the user-defined property value to.
propname -- A string containing the name of the property
dtype -- WTK Data Type of the property.

RETURN TYPE:
FLAG is TRUE if the function was successful.

Assignment 10

project definition:

Creates a universe with a bordered window in monoscopic mode..
Create a cylinder that has a height of 40, a radius of 5, 12 tessellation lines, is single sided and gouraud shaded.
Create a sphere with a radius of 10, 12 lat and long divisions, is single sided, and gouraud shaded.
Create a movable geometry node for the cylinder whose parent is the root node.
Create a movable geometry nodes for the sphere whose parent is the root node.
Create and instance of the movable node containing the sphere as the 2^nd child of the root node
Set the translation of the movable geometry containing the first sphere to (0,-20,0)
Set the translation of the movable geometry containing the second sphere to (0,20,0)
Zooms the view in the window
Create an action function that allows the user to:
- press q to quit
- press p to print the scene graph from the root node. (use WTnode print)
- press i on the keyboard to get the the position of the viewpoint using the WTproperty_get function, and print it to the screen.
- press I on the keyboard to get the position of the viewpoint using the WTproperty_getp3 function, and print it to the screen.
- press S on the keyboard to get the value of the position of th veiepoint using the WTproperty_getasstring function, and print it to the screen.
- press X on the keyboard to translate the viewpoint one unit in the positive X direction in world coordinates.
- add a name property to the viewpoint and set its name to Viewpoint-1
- press N on the keyboard to print the name of the vewpoint to the screen.

Other Property functions

Function	Description
FLAG WTproperty_delete(void object, const char propname);	Deletes the specified property from the object
FLAG WTproperty_exists(void object, const char propname);	Returns true if the specifed proptery for the specified object exists
void WTproperty_setdata(void object, const charpropname, void *data);	Sets the user-defined data field for a property.
void WTproperty_getddata(void object, const char *propname);	Returns the user-defined data field for a property.
WTdatattype WTproperty_getdatatype(void object, const char propname);	Returns the datatype of the specified objects propname
unisgnhed int WTproperty_getsizeofdata(void object, const char propname);	Returns the number of bytes used by the specified objects property name value.
char * WTvalue_tostring(WTdatatype dtype, void *value);	Returns the value of the dtype argument as a string. Strings returned are only good until another call to WTvalue_tostring is executed.

Events

Events occur what the value of a property is set, even if it is set to its current value.

The value of the propety change generates an event that can be acted upon by creating an event handler for that objects property.

Events are fired right before the universe's action function is called

If the universe simulation loop is not running event;s can be executed by calling the WTuniverse_processevents function

One property can have numberous events

Event handlers are give a pointer to the object, the property taht generated the event, the new value of the property, the source from which teh property cange event was generated, and the time the event was generated.

Creating an event function:

There is a two step process for creating event handlers and associating them with a property.

1. Create the event handler.
2. Call WTproperty_add handler function to associate the event handler function with the object and property.

The following example executes the MyEventHandler function when the viewpoint changes position.

Example:

void MyEventHandler(void *object, const char *propname, void *value, double time, WTeventsource src);

void MyEventHandler(void *object, const char *propname, void *value, double time, WTeventsource src)
{
/*code to execute when the event occurs */
}

WTproperty_addhandler(WTuniverse_getviewpoints(), WTVIEWPOINT_POSITION, MyEventHandler);

Event Handler Arguments

object -- pointer to the object whos property generated the event
propname -- string value containing he name of the property
value -- pointer to the new value coming into the function
time -- time the event was generated
src -- the source of the event can be on of the following constant values
WTLOCAL -- events generated from the local computer
WTNETWORK -- event generated another computer in a W2W simulation
WTLOCAL_TIMER and WTNETWORKTIMER -- event generated from a value set by WTproperty_setat function

WTproperty_addhandler:

SYNTAX:
FLAG WTproperty_addhandler(void *object, const char*propname, WTeventhandler eh);

ARGUMENTS:
object -- the object to add the event handler to
propname -- The property to generate the event
WTeventhandler -- The name of the event handler function.

RETURN TYPE:
FLAG is TRUE if the function was successful.

Assignment 11

project definition:

Creates a universe with a bordered window in monoscopic mode..
Create a cylinder that has a height of 40, a radius of 5, 12 tessellation lines, is single sided and gouraud shaded.
Create a sphere with a radius of 10, 12 lat and long divisions, is single sided, and gouraud shaded.
Create a movable geometry node for the cylinder whose parent is the root node.
Create a movable geometry nodes for the sphere whose parent is the root node.
Create and instance of the movable node containing the sphere as the 2^nd child of the root node
Set the translation of the movable geometry containing the first sphere to (0,-20,0)
Set the translation of the movable geometry containing the second sphere to (0,20,0)
Zooms the view in the window
Create an action function that allows the user to:
- press q to quit
- press p to print the scene graph from the root node. (use WTnode print)
- press i on the keyboard to get the the position of the viewpoint using the WTproperty_get function, and print it to the screen.
- press I on the keyboard to get the position of the viewpoint using the WTproperty_getp3 function, and print it to the screen.
- press S on the keyboard to get the value of the position of th veiepoint using the WTproperty_getasstring function, and print it to the screen.
- press X on the keyboard to translate the viewpoint one unit in the positive X direction in world coordinates.
- add a name property to the viewpoint and set its name to Viewpoint-1
- press N on the keyboard to print the name of the vewpoint to the screen.
- Add an eventhandler call mouse_handler that will print the name of the property that generated it.
HINT: The event should be generated by the WTWINDOW_LBUTTON down property of the WTK window.

Creating new user-defined Objects (WTbase Objects)

WTbase object type allows you to create generic, empty objects, distinguished only by the properties that you add to them. Just like the other object types supported by the WTK OPE architecture, you can add properties, event handlers, and share those properties across a network.

WTK object types that are not supported by the OPE architecture cannot contain properties and thus, do not genetrat events or allow the sharing of data over a network

To extend the OPE paradigm, create WTbase objects and user-defined properties to represent the desired attributes of the unsupported objects.

WTdatatype	Actual Data Type
WTINT	int
WTUINT	unsigned int
WTFLOAT	float
WTDOUBLE	double
WTP2	float[2]
WTP3	float[3]
WTQ	float[4]
WTSTRING	char *
WTPOINTER	void *

WTanchornode Properties	Data Type	Description
WTANCHOR_LOCATION	WTSTRING

WTfognode Properties	Data Type	Description
WTFOG_COLOR	WTQ	(R,G,B,A)
WTFOG_LINEARSTART	WTFLOAT
WTFOG_MODE	WTINT
WTFOG_RANGE	WTFLOAT

WTinlinenode Properties	Data Type	Description
WTINLINE_LOCATION	WTSTRING

WTlightnode Properties	Data Type	Description
WTLIGHT_AMBIENT	WTP3	Ambient Color (R,G,B)
WTLIGHT_ANGLE	WTFLOAT
WTLIGHT_ATTENUATION	WTP3
WTLIGHT_DIFFUSE	WTP3	Diffuse Color (R,G,B)
WTLIGHT_DIRECTION	WTP3	Direction Vector (normalized)
WTLIGHT_EXPONENT	WTFLOAT
WTLIGHT_INTENSITY	WTFLOAT	Intensity of the light
WTLIGHT_POSITION	WTP3	Position of the light
WTLIGHT_SPECULAR	WTP3	Specular color of the light

WTlodnode Properties	Data Type	Description
WTLOD_CENTER	WTP3
WTLOD_RANGE	WTSTRING ("range;range;range")

WTmovnode Properties	Data Type	Description
WTMOVNODE_ATTACHMENTS	WTSTRING ("name,name,name")	list of the name of the attached nodes

WTnode Properties	Data Type	Description
WTNODE_BOUNDINGBOX	WTINT	Bounding box ON or OFF
WTNODE_CHILDREN	WTSTRING (name;name;name)	List of the names of the child nodes
WTNODE_ENABLED	WTINT	Is the node ON or OFF
WTNODE_ROTATION	WTQ	The rotation of the node in parent frame
WTNODE_TRANSLATION	WTP3	The translation of the node in parent frame

WTsepnode Properties	Data Type	Description
WTSEP_CULLMODE	WTINT	Culling ON or OFF

WTswitchnode Properties	Data Type	Description
WTSWITCH_WHICHCHILD	WTINT	The current active child of the switch

WTviewpoint Properties	Data Type	Description
WTVIEWPOINT_ASPECT	WTFLOAT
WTVIEWPOINT_CONVDISTANCE	WTFLOAT	Convergence Distance
WTVIEWPOINT_CONVERGENCE	WTINT
WTVIEWPOINT_ORIENTATION	WTQ	The orientation of the viewpoint
WTVIEWPOINT_PARALLAX	WTFLOAT
WTVIEWPOINT_POSITION	WTP3	The position of the viewpoint

WTwindow Properties	Data Type	Description
WTWINDOW_BGRGB	WTP3	Window background color
WTWINDOW_BOTTOMRIGHT	WTP2	Bottom right coroner of the window
WTWINDOW_ENABLED	WTNT	Window ON or OFF
WTWINDOW_EYE	WTINT	The eye (left or right) the window is being rendered from
WTWINDOW_HITHER	WTFLOAT	Position of hither clipping plane
WTWINDOW_KEY	WTINT	ASCII value of a key press when window has focus
WTWINDOW_LBUTTON	WTINT	Left mouse button clicked in window
WTWINDOW_LBUTTONDBLCLICK	WTINT	Left mouse button double clicked in the window
WTWINDOW_RBUTTON	WTINT	Right mouse button clicked in window
WTWINDOW_RBUTTONDBLCLICK	WTINT	Right mouse button double clicked in window
WTWINDOW_MBUTTON	WTINT	Middle mouse button clicked in window
WTWINDOW_MBUTTONDBLCLICK	WTINT	Middle mouse button dowble clicked in the window
WTWINDOW_POSITION	WTPT	Position of the window
WTWINDOW_PROJECTION	WTINT	Projection type
WTWINDOW_ROOTNODE	WTSTRING	Name of the root node for this window
WTWINDOW_SIZE	WTP2
WTWINDOW_TOPLEFT	WTP2	Position of the top left corner of the window
WTWINDOW_VIEWANGLE	WTFLOAT	The view angle of the window
WTWINDOW_VIEWPOINT	WTSTRING	The viewpoint in the window
WTWINDOW_VIEWPOINT2	WTSTRING
WTWINDOW_YON	WTFLOAT	The position of the Yon (far) clipping plane

WTsensor Properties	Data Type	Description
WTSENSOR_ANGULARRATE	WTFLOAT	The angular rate of the sensor
WTSENSOR_LASTROTATION	WTQ	The last (previous) rotation record from the sensor
WTSENSOR_LASTTRANSLATION	WTP3	The last (previous) translation record from the sensor
WTSENSOR_MISCDATA	WTINT	The misc data structure from the sensor
WTSENSOR_RAWDATA	WTPOINTER	Pointer to the raw data structure for the sensor
WTSENSOR_ROTATION	WTQ	The current rotation record from the sensor
WTSENSOR_ROTATIONALOFFSET	WTQ
WTSENSOR_SENSITIVITY	WTFLOAT	The sensitivity of the sensor (translational)
WTSENSOR_TRANSLATION	WTP3	The current translation record from the sensor
WTSENSOR_UPDATEFN	WTPOINTER	Pointer to the Update function of the sensor

WTpath Properties	Data Type	Description
WTPATH_CONSTRAINTS	WTINT
WTPATH_DIRECTION	WTINT	Play direction of the path
WTPATH_MARKER	WTPOINTER	Pointer to the geometry used as a marker
WTPATH_MODE	WTINT	Play mode for the path
WTPATH_PLAYING	WTINT	Play state of the path
WTPATH_PLAYSPEED	WTINT	Play speed of the path
WTPATH_ROTATION	WTQ
WTPATH_RECORDING	WTINT	Recording state of the path
WTPATH_RECORDLINK	WTPOINTER	Pointer the the motionlink to use for recording
WTPATH_SAMPLES	WTINT
WTPATH_TRANSLATION	WTP3
WTPATH_VISIBILITY	WTNT

Function Name	WTK data type	Syntax	Description
WTproperty_geti	WTINT	int WTproperty_geti( void object, const charpropname);	Returns a property with a WTINT data type.
WTproperty_getui	WTUINT	unsigned int WTpropert_getui( void object, const charpropname);	Retuns a propery with a WTUINT data type.
WTproperty_getf	WTFLOAT	float WTpropert_getf( void object, const charpropname);	Returns a property with a WTFLOAT data type.
WTproperty_getd	WTDOUBLE	double WTpropert_getd( void object, const charpropname);	Returns a property with a WTDOUBLE data type.
WTproperty_getp2	WTP2	FLAG WTpropert_getp2( void object, const charpropname WTp2 value);	Places the value of the property in its value argument.
WTproperty_getp3	WTP3	FLAG WTpropert_getp3( void object, const charpropname WTp3 value);	Places the value of the property in its value argument.
WTproperty_getq	WTQ	FLAG WTpropert_getq( void object, const charpropname WTQ value);	Places the value of the property in its value argument.
WTproperty_gets	WTSTRING	char * WTpropert_getsi( void object, const charpropname);	Returns a property with a WTDOUBLE data type. NOTE: The char* reusult of retrieving a WTSTRING property value is a pointer to the actual string stored in WTK. DO NOT modify this directly with calls to WTfree, WTrealloc, strcat, strcpy, etc. If you need to modify the string value, make a local copy of the string before modifying it.
WTproperty_getp	WTPOINTER	void * WTpropert_getp( void *object);	Returns the property with a WTPOINTER data type.