Package org.lwjgl.ovr

Class OVRUtil

java.lang.Object

org.lwjgl.ovr.OVRUtil

public class OVRUtil
extends java.lang.Object

Native bindings to the libOVR utility functions.

Field Summary

Fields

Modifier and Type	Field and Description
static int	ovrProjection_ClipRangeOpenGL Enable if the application is rendering with OpenGL and expects a projection matrix with a clipping range of (-w to w).
static int	ovrProjection_FarClipAtInfinity When this flag is used, the zfar value pushed into Matrix4f_Projection will be ignored NOTE: Enable only if Projection_FarLessThanNear is also enabled where the far clipping plane will be pushed to infinity.
static int	ovrProjection_FarLessThanNear After the projection transform is applied, far values stored in the depth buffer will be less than closer depth values.
static int	ovrProjection_LeftHanded Enable if using left-handed transformations in your application.
static int	ovrProjection_None Use for generating a default projection matrix that is: Right-handed. Near depth values stored in the depth buffer are smaller than far depth values. Both near and far are explicitly defined. With a clipping range that is (0 to w).

Method Summary

Modifier and Type	Method and Description
static void	ovr_CalcEyePoses(OVRPosef headPose, OVRVector3f.Buffer HmdToEyeOffset, OVRPosef.Buffer outEyePoses) Computes offset eye poses based on headPose returned by OVRTrackingState.
static OVRDetectResult	ovr_Detect(int timeoutMilliseconds, OVRDetectResult __result) Detects Oculus Runtime and Device Status.
static void	ovr_GetEyePoses(long session, long frameIndex, boolean latencyMarker, OVRVector3f.Buffer hmdToEyeOffset, OVRPosef.Buffer outEyePoses, double[] outSensorSampleTime) Array version of: _GetEyePoses
static void	ovr_GetEyePoses(long session, long frameIndex, boolean latencyMarker, OVRVector3f.Buffer hmdToEyeOffset, OVRPosef.Buffer outEyePoses, java.nio.DoubleBuffer outSensorSampleTime) Returns the predicted head pose in outHmdTrackingState and offset eye poses in outEyePoses.
static OVRMatrix4f	ovrMatrix4f_OrthoSubProjection(OVRMatrix4f projection, OVRVector2f orthoScale, float orthoDistance, float HmdToEyeOffsetX, OVRMatrix4f __result) Generates an orthographic sub-projection.
static OVRMatrix4f	ovrMatrix4f_Projection(OVRFovPort fov, float znear, float zfar, int projectionModFlags, OVRMatrix4f __result) Used to generate projection from ovrEyeDesc::Fov.
static void	ovrPosef_FlipHandedness(OVRPosef inPose, OVRPosef outPose) Tracking poses provided by the SDK come in a right-handed coordinate system.
static OVRTimewarpProjectionDesc	ovrTimewarpProjectionDesc_FromProjection(OVRMatrix4f projection, int projectionModFlags, OVRTimewarpProjectionDesc __result) Extracts the required data from the result of Matrix4f_Projection.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ovrProjection_None

public static final int ovrProjection_None

Use for generating a default projection matrix that is:

• Right-handed.
• Near depth values stored in the depth buffer are smaller than far depth values.
• Both near and far are explicitly defined.
• With a clipping range that is (0 to w).

See Also:

Constant Field Values

ovrProjection_LeftHanded

public static final int ovrProjection_LeftHanded

Enable if using left-handed transformations in your application.

See Also:

Constant Field Values

ovrProjection_FarLessThanNear

public static final int ovrProjection_FarLessThanNear

After the projection transform is applied, far values stored in the depth buffer will be less than closer depth values. NOTE: Enable only if the application is using a floating-point depth buffer for proper precision.

See Also:

Constant Field Values

ovrProjection_FarClipAtInfinity

public static final int ovrProjection_FarClipAtInfinity

When this flag is used, the zfar value pushed into Matrix4f_Projection will be ignored NOTE: Enable only if Projection_FarLessThanNear is also enabled where the far clipping plane will be pushed to infinity.

See Also:

Constant Field Values

ovrProjection_ClipRangeOpenGL

public static final int ovrProjection_ClipRangeOpenGL

Enable if the application is rendering with OpenGL and expects a projection matrix with a clipping range of (-w to w). Ignore this flag if your application already handles the conversion from D3D range (0 to w) to OpenGL.

See Also:

Constant Field Values

Method Detail

ovr_Detect

public static OVRDetectResult ovr_Detect(int timeoutMilliseconds,
                                         OVRDetectResult __result)

Detects Oculus Runtime and Device Status.

Checks for Oculus Runtime and Oculus HMD device status without loading the LibOVRRT shared library. This may be called before _Initialize to help decide whether or not to initialize LibOVR.

Parameters:

timeoutMilliseconds - a timeout to wait for HMD to be attached or 0 to poll

ovrMatrix4f_Projection

public static OVRMatrix4f ovrMatrix4f_Projection(OVRFovPort fov,
                                                 float znear,
                                                 float zfar,
                                                 int projectionModFlags,
                                                 OVRMatrix4f __result)

Used to generate projection from ovrEyeDesc::Fov.

Parameters:

fov - the OVRFovPort to use

znear - distance to near Z limit

zfar - distance to far Z limit

projectionModFlags - a combination of the ovrProjectionModifier flags. One or more of:

Projection_None	Projection_FarLessThanNear	Projection_FarClipAtInfinity
Projection_ClipRangeOpenGL

__result - the calculated projection matrix

ovrTimewarpProjectionDesc_FromProjection

public static OVRTimewarpProjectionDesc ovrTimewarpProjectionDesc_FromProjection(OVRMatrix4f projection,
                                                                                 int projectionModFlags,
                                                                                 OVRTimewarpProjectionDesc __result)

Extracts the required data from the result of Matrix4f_Projection.

Parameters:

projection - the project matrix from which to extract OVRTimewarpProjectionDesc

projectionModFlags - a combination of the ovrProjectionModifier flags. One or more of:

Projection_None	Projection_FarLessThanNear	Projection_FarClipAtInfinity
Projection_ClipRangeOpenGL

__result - the extracted ovrTimewarpProjectionDesc

ovrMatrix4f_OrthoSubProjection

public static OVRMatrix4f ovrMatrix4f_OrthoSubProjection(OVRMatrix4f projection,
                                                         OVRVector2f orthoScale,
                                                         float orthoDistance,
                                                         float HmdToEyeOffsetX,
                                                         OVRMatrix4f __result)

Generates an orthographic sub-projection.

Used for 2D rendering, Y is down.

Parameters:

projection - the perspective matrix that the orthographic matrix is derived from

orthoScale - equal to 1.0f / pixelsPerTanAngleAtCenter

orthoDistance - equal to the distance from the camera in meters, such as 0.8m

HmdToEyeOffsetX - the offset of the eye from the center

__result - the calculated projection matrix

ovr_CalcEyePoses

public static void ovr_CalcEyePoses(OVRPosef headPose,
                                    OVRVector3f.Buffer HmdToEyeOffset,
                                    OVRPosef.Buffer outEyePoses)

Computes offset eye poses based on headPose returned by OVRTrackingState.

Parameters:

headPose - indicates the HMD position and orientation to use for the calculation

HmdToEyeOffset - can be OVREyeRenderDesc.HmdToEyeViewOffset returned from _GetRenderDesc. For monoscopic rendering, use a vector that is the average of the two vectors for both eyes.

outEyePoses - if outEyePoses are used for rendering, they should be passed to _SubmitFrame in OVRLayerEyeFov::RenderPose or OVRLayerEyeFovDepth::RenderPose

ovr_GetEyePoses

public static void ovr_GetEyePoses(long session,
                                   long frameIndex,
                                   boolean latencyMarker,
                                   OVRVector3f.Buffer hmdToEyeOffset,
                                   OVRPosef.Buffer outEyePoses,
                                   java.nio.DoubleBuffer outSensorSampleTime)

Returns the predicted head pose in outHmdTrackingState and offset eye poses in outEyePoses.

This is a thread-safe function where caller should increment frameIndex with every frame and pass that index where applicable to functions called on the rendering thread. Assuming outEyePoses are used for rendering, it should be passed as a part of OVRLayerEyeFov. The caller does not need to worry about applying HmdToEyeOffset to the returned outEyePoses variables.

Parameters:

session - an ovrSession previously returned by _Create

frameIndex - the targeted frame index, or 0 to refer to one frame after the last time _SubmitFrame was called

latencyMarker - Specifies that this call is the point in time where the "App-to-Mid-Photon" latency timer starts from. If a given ovrLayer provides "SensorSampleTimestamp", that will override the value stored here.

hmdToEyeOffset - can be OVREyeRenderDesc.HmdToEyeOffset returned from _GetRenderDesc. For monoscopic rendering, use a vector that is the average of the two vectors for both eyes.

outEyePoses - the predicted eye poses

outSensorSampleTime - the time when this function was called. May be NULL, in which case it is ignored.

ovrPosef_FlipHandedness

public static void ovrPosef_FlipHandedness(OVRPosef inPose,
                                           OVRPosef outPose)

Tracking poses provided by the SDK come in a right-handed coordinate system. If an application is passing in Projection_LeftHanded into Matrix4f_Projection, then it should also use this function to flip the HMD tracking poses to be left-handed.

While this utility function is intended to convert a left-handed OVRPosef into a right-handed coordinate system, it will also work for converting right-handed to left-handed since the flip operation is the same for both cases.

Parameters:

inPose - a pose that is right-handed

outPose - the pose that is requested to be left-handed (can be the same pointer to inPose)

ovr_GetEyePoses

public static void ovr_GetEyePoses(long session,
                                   long frameIndex,
                                   boolean latencyMarker,
                                   OVRVector3f.Buffer hmdToEyeOffset,
                                   OVRPosef.Buffer outEyePoses,
                                   double[] outSensorSampleTime)

Array version of: _GetEyePoses