Configuring nodes

An application would usually want to fully configure a node before it starts streaming data. For that reason, OpenNI defines a flow in which configuration can take place, and once all configuration is set, the node xn::Generator::StartGenerating() method can be called to make it start streaming the data.

The following code creates a depth generator, configures it to VGA resolution, 30 FPS, and then starts it:

// Create a DepthGenerator node
xn::DepthGenerator depth;
nRetVal = depth.Create(context);
// TODO: check error code
XnMapOutputMode outputMode;
outputMode.nXRes = 640;
outputMode.nYRes = 480;
outputMode.nFPS = 30;
nRetVal = depth.SetMapOutputMode(outputMode);
// TODO: check error code
// We're done configuring it. Make it start generating data
nRetVal = context.StartGeneratingAll();
// TODO: check error code
// Main loop
while (bShouldRun)
{
// Wait for new data to be available
nRetVal = context.WaitOneUpdateAll(depth);
if (nRetVal != XN_STATUS_OK)
{
printf("Failed updating data: %s\n", xnGetStatusString(nRetVal));
continue;
}
// Take current depth map
const XnDepthPixel* pDepthMap = depth.GetDepthMap();
// TODO: process depth map
}
XN_STATUS_OK
#define XN_STATUS_OK
Definition XnStatus.h:37
xnGetStatusString
XN_C_API const XnChar *XN_C_DECL xnGetStatusString(const XnStatus Status)
XnDepthPixel
XnUInt16 XnDepthPixel
Definition XnTypes.h:276
xn::DepthGenerator
Definition XnCppWrapper.h:4695
xn::DepthGenerator::GetDepthMap
const XnDepthPixel * GetDepthMap() const
Gets the current depth-map. This map is updated after a call to xnWaitAndUpdateData()....
Definition XnCppWrapper.h:4739
xn::DepthGenerator::Create
XnStatus Create(Context &context, Query *pQuery=NULL, EnumerationErrors *pErrors=NULL)
Creates a DepthGenerator node from available production node alternatives.
Definition XnCppWrapper.h:9801
xn::MapGenerator::SetMapOutputMode
XnStatus SetMapOutputMode(const XnMapOutputMode &OutputMode)
Sets the current map output mode of the generator node.
Definition XnCppWrapper.h:4304
XnMapOutputMode
Definition XnTypes.h:433
XnMapOutputMode::nXRes
XnUInt32 nXRes
Definition XnTypes.h:435
XnMapOutputMode::nYRes
XnUInt32 nYRes
Definition XnTypes.h:437
XnMapOutputMode::nFPS
XnUInt32 nFPS
Definition XnTypes.h:439