C++ API Documentation
This is the API Documentation for the C++ Interface of dnkvw.
context
always to refers to a dnkvw context.
IDnkvwHandle dnkvw_createContext();
This method creates a new dnkvw context. It is needed for all operations in this library. Do not forget to free it after you are done with it.
Returns:
- the newly created context
void dnkvw_freeContext(IDnkvwHandle* context);
This method deinitializes and frees a dnkw context. If you use C++ NEVER use ‘delete’ to free an existing context. Only use this method to free a context.
Parameters:
context
a pointer to an initialized context
void context->setLogLevel(int logLevel);
Set the log level.
Parameters:
logLevel
the log level
Logging defaults:
- Debug: Dnkvw = Verbose
- Release: Dnkvw = Warning
void context->setInternalLogLevel(int internalLogLevel);
Set the internal log level. Not intended for production use.
Parameters:
internalLogLevel
the log level
Logging defaults:
- Debug: Internal = Silent
- Release: Internal = Silent
bool context->selectHaarTracker();
Use Haar tracking. Overwrites previously selected tracker.
Returns:
true
if the selection was successful
bool context->selectDnnTracker();
Use DNN tracking. Overwrites previously selected tracker.
Returns:
true
if the selection was successful
bool context->startTracking(int cameraId);
Starts the tracking.
Parameters:
cameraId
the Id of the camera to be uses for tracking
Returns:
true
if the tracking could be started successfully. Afalse
value may indicate a problem with the camera.
void context->stopTracking();
Stops the tracking. This function may block.
void context->stopTrackingAsync();
Stops the tracking as soon as possible without blocking.
void context->configureFrustum(float aspectRatio, float nearPlane);
Configures the viewing frustum according to the parameters.
Parameters:
aspectRatio
the aspect rationearPlane
the near plane
void context->calibrate();
Runs a short calibration routine. The user should sit or stand as centered as possible before this function is called. The position of the user will be used as the new center until a new calibration is started.
This method should be called shortly after the start of the tracking to correct perspective problems caused by a wrong starting center.
void context->loadFrustum(float* left, float* right, float* top, float* bottom);
Get the last frustum. The viewing frustum is the volume that may appear on the screen. It is described by a near plane, a far plane and the distances of the left, right, top and bottom plane based on the near plane. This function returns only the left, right, top and bottom values. The near and far plane can be set independently.
These values can be used to calculate the projection matrix. This is normally done by your 3D graphics framework. Look at our demos for some case specific examples.
For more information see https://en.wikipedia.org/wiki/Viewing_frustum
Parameters:
left
a pointer to a float where the left result can be savedright
a pointer to a float where the right result can be savedtop
a pointer to a float where the top result can be savedbottom
a pointer to a float where the bottom result can be saved
void context->loadEyeOffset(float* x, float* y, float* z);
Get the last calculated eye offset.
Parameters:
x
a pointer to a float where the X result can be savedy
a pointer to a float where the Y result can be savedz
a pointer to a float where the Z result can be saved
void context->loadFps(float* fps);
Get the last FPS value.
Parameters:
fps
a pointer to a float where the result can be saved
void context->debugCameraInput(int cameraId);
Debugging function to test the camera input. Should not be called while the tracking thread is running. This function may block. Don’t use this in production code.
Parameters:
cameraId
Id of the camera to use for tracking
void context->debugCameraFace(int cameraId);
Debugging function to test the face detection.
Should not be called while the tracking thread is running.
This function may block.
Don’t use this in production code.
Parameters:
cameraId
Id of the camera to use for tracking