HID Sensor Usage Tables - USB.org

100 HID Sensor Usages
Here is an example for SENSOR_DATA_TYPE_ORIENTATION_ROTATION_MATRIX:
struct _rotation_matrix {
float fM11; // matrix[1][1]
float fM12; // matrix[1][2]
float fM13; // matrix[1][3]
float fM21; // matrix[2][1]
float fM22; // matrix[2][2]
float fM23; // matrix[2][3]
float fM31; // matrix[3][1]
float fM32; // matrix[3][2]
float fM33; // matrix[3][3]
} RotationMatrix;
FLAT_VARIANT_UNION fvu;
fvu.vecVal.caubElems = (unsigned long)sizeof(RotationMatrix);
struct _rotation_matrix *pRM = (struct _rotation_matrix *)fvu.vecVal.paubElems;
pRM->fM11 = 1.0;
pRM->fM12 = 0.0;
pRM->fM13 = 0.0;
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Here is an example for SENSOR_DATA_TYPE_ORIENTATION_QUATERNION:
struct _quaternion {
float fW; // real axis component
float fX; // imaginary “i” axis component
float fY; // imaginary “j” axis component
float fZ; // imaginary “k” axis component
} Quaternion;
FLAT_VARIANT_UNION fvu;
fvu.vecVal.caubElems = (unsigned long)sizeof(Quaternion);
struct _quaternion *pQ = (struct _quaternion *)fvu.vecVal.paubElems;
pQ->fW = 1.0;
pQ->fX = 0.0;
pQ->fY = 0.0;
pQ->fZ = 0.0;
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There are two ways to identify a Property or Data Field:
1. Using simply the PROPERTYKEY field;
2. Using a more expressive GUID_OR_PROPERTYKEY field.
For convenience, the PROPERTYKEY and the VARIANT value can be combined together as follows:
typedef struct _HID_SENSOR_PROPERTYKEY_VALUE_PAIR {
PROPERTYKEY key;
FLAT_VARIANT_UNION fvu;
} HID_SENSOR_PROPERTYKEY_VALUE_PAIR;
Or the GUID_OR_PROPERTYKEY and the VARIANT value can be combined together as follows:
typedef struct _HID_SENSOR_GorPK_VALUE_PAIR {
GUID_OR_PROPERTYKEY GorPK;
FLAT_VARIANT_UNION fvu;
} HID_SENSOR_GorPK_VALUE_PAIR;
In order to disambiguate which of the data types in the FLAT_VARIANT_UNION are actually being used:
The platform driver must be able to deduce the correct type “expected” for the specified
PROPERTYKEY;
The GUID_OR_PROPERTYKEY field has included type information that the platform driver can
use to extract the data and map it to the “expected” data type for the specified PROPERTYKEY.
The GUID_OR_PROPERTYKEY field is defined as follows: