public Class EXTCalibratedTimestamps

The extension name.

The extension specification version.

Extends VkStructureType.

VkTimeDomainEXT - Supported time domains

Description

• TIME_DOMAIN_DEVICE_EXT specifies the device time domain. Timestamp values in this time domain use the same units and are comparable with device timestamp values captured using CmdWriteTimestamp or CmdWriteTimestamp2 and are defined to be incrementing according to the timestampPeriod of the device.
• TIME_DOMAIN_CLOCK_MONOTONIC_EXT specifies the CLOCK_MONOTONIC time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT specifies the CLOCK_MONOTONIC_RAW time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC_RAW, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT specifies the performance counter (QPC) time domain available on Windows. Timestamp values in this time domain are in the same units as those provided by the Windows QueryPerformanceCounter API and are comparable with platform timestamp values captured using that API as computed by this example:

LARGE_INTEGER counter;
QueryPerformanceCounter(&counter);
return counter.QuadPart;

See Also

VkCalibratedTimestampInfoEXT, GetPhysicalDeviceCalibrateableTimeDomainsEXT

VkTimeDomainEXT - Supported time domains

Description

• TIME_DOMAIN_DEVICE_EXT specifies the device time domain. Timestamp values in this time domain use the same units and are comparable with device timestamp values captured using CmdWriteTimestamp or CmdWriteTimestamp2 and are defined to be incrementing according to the timestampPeriod of the device.
• TIME_DOMAIN_CLOCK_MONOTONIC_EXT specifies the CLOCK_MONOTONIC time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT specifies the CLOCK_MONOTONIC_RAW time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC_RAW, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT specifies the performance counter (QPC) time domain available on Windows. Timestamp values in this time domain are in the same units as those provided by the Windows QueryPerformanceCounter API and are comparable with platform timestamp values captured using that API as computed by this example:

LARGE_INTEGER counter;
QueryPerformanceCounter(&counter);
return counter.QuadPart;

See Also

VkCalibratedTimestampInfoEXT, GetPhysicalDeviceCalibrateableTimeDomainsEXT

VkTimeDomainEXT - Supported time domains

Description

• TIME_DOMAIN_DEVICE_EXT specifies the device time domain. Timestamp values in this time domain use the same units and are comparable with device timestamp values captured using CmdWriteTimestamp or CmdWriteTimestamp2 and are defined to be incrementing according to the timestampPeriod of the device.
• TIME_DOMAIN_CLOCK_MONOTONIC_EXT specifies the CLOCK_MONOTONIC time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT specifies the CLOCK_MONOTONIC_RAW time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC_RAW, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT specifies the performance counter (QPC) time domain available on Windows. Timestamp values in this time domain are in the same units as those provided by the Windows QueryPerformanceCounter API and are comparable with platform timestamp values captured using that API as computed by this example:

LARGE_INTEGER counter;
QueryPerformanceCounter(&counter);
return counter.QuadPart;

See Also

VkCalibratedTimestampInfoEXT, GetPhysicalDeviceCalibrateableTimeDomainsEXT

VkTimeDomainEXT - Supported time domains

Description

• TIME_DOMAIN_DEVICE_EXT specifies the device time domain. Timestamp values in this time domain use the same units and are comparable with device timestamp values captured using CmdWriteTimestamp or CmdWriteTimestamp2 and are defined to be incrementing according to the timestampPeriod of the device.
• TIME_DOMAIN_CLOCK_MONOTONIC_EXT specifies the CLOCK_MONOTONIC time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT specifies the CLOCK_MONOTONIC_RAW time domain available on POSIX platforms. Timestamp values in this time domain are in units of nanoseconds and are comparable with platform timestamp values captured using the POSIX clock_gettime API as computed by this example:

struct timespec tv;
clock_gettime(CLOCK_MONOTONIC_RAW, &tv);
return tv.tv_nsec + tv.tv_sec*1000000000ull;

• TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT specifies the performance counter (QPC) time domain available on Windows. Timestamp values in this time domain are in the same units as those provided by the Windows QueryPerformanceCounter API and are comparable with platform timestamp values captured using that API as computed by this example:

LARGE_INTEGER counter;
QueryPerformanceCounter(&counter);
return counter.QuadPart;

See Also

VkCalibratedTimestampInfoEXT, GetPhysicalDeviceCalibrateableTimeDomainsEXT

Unsafe version of: GetCalibratedTimestampsEXT

Parameters

timestampCount:int

the number of timestamps to query.

Unsafe version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT

Parameters

pTimeDomainCount:long

a pointer to an integer related to the number of calibrateable time domains available or queried, as described below.

Query calibrated timestamps.

C Specification

In order to be able to correlate the time a particular operation took place at on timelines of different time domains (e.g. a device operation vs. a host operation), Vulkan allows querying calibrated timestamps from multiple time domains.

To query calibrated timestamps from a set of time domains, call:

VkResult vkGetCalibratedTimestampsEXT(
    VkDevice                                    device,
    uint32_t                                    timestampCount,
    const VkCalibratedTimestampInfoEXT*         pTimestampInfos,
    uint64_t*                                   pTimestamps,
    uint64_t*                                   pMaxDeviation);

Description

Calibrated timestamp values can be extrapolated to estimate future coinciding timestamp values, however, depending on the nature of the time domains and other properties of the platform extrapolating values over a sufficiently long period of time may no longer be accurate enough to fit any particular purpose, so applications are expected to re-calibrate the timestamps on a regular basis.

Valid Usage (Implicit)

• device must be a valid VkDevice handle
• pTimestampInfos must be a valid pointer to an array of timestampCount valid VkCalibratedTimestampInfoEXT structures
• pTimestamps must be a valid pointer to an array of timestampCount uint64_t values
• pMaxDeviation must be a valid pointer to a uint64_t value
• timestampCount must be greater than 0

Return Codes

On success, this command returns

• SUCCESS

On failure, this command returns

• ERROR_OUT_OF_HOST_MEMORY
• ERROR_OUT_OF_DEVICE_MEMORY

See Also

VkCalibratedTimestampInfoEXT

Parameters

device:VkDevice

the logical device used to perform the query.

pTimestampInfos:VkCalibratedTimestampInfoEXT.Buffer

a pointer to an array of timestampCount VkCalibratedTimestampInfoEXT structures, describing the time domains the calibrated timestamps should be captured from.

pTimestamps:LongBuffer

a pointer to an array of timestampCount 64-bit unsigned integer values in which the requested calibrated timestamp values are returned.

pMaxDeviation:LongBuffer

a pointer to a 64-bit unsigned integer value in which the strictly positive maximum deviation, in nanoseconds, of the calibrated timestamp values is returned.

Annotations

@NativeType:VkResult

Array version of: GetCalibratedTimestampsEXT

Annotations

@NativeType:VkResult

Query calibrateable time domains.

C Specification

To query the set of time domains for which a physical device supports timestamp calibration, call:

VkResult vkGetPhysicalDeviceCalibrateableTimeDomainsEXT(
    VkPhysicalDevice                            physicalDevice,
    uint32_t*                                   pTimeDomainCount,
    VkTimeDomainEXT*                            pTimeDomains);

Description

If pTimeDomains is NULL, then the number of calibrateable time domains supported for the given physicalDevice is returned in pTimeDomainCount. Otherwise, pTimeDomainCount must point to a variable set by the user to the number of elements in the pTimeDomains array, and on return the variable is overwritten with the number of values actually written to pTimeDomains. If the value of pTimeDomainCount is less than the number of calibrateable time domains supported, at most pTimeDomainCount values will be written to pTimeDomains, and INCOMPLETE will be returned instead of SUCCESS, to indicate that not all the available time domains were returned.

Valid Usage (Implicit)

• physicalDevice must be a valid VkPhysicalDevice handle
• pTimeDomainCount must be a valid pointer to a uint32_t value
• If the value referenced by pTimeDomainCount is not 0, and pTimeDomains is not NULL, pTimeDomains must be a valid pointer to an array of pTimeDomainCount VkTimeDomainEXT values

Return Codes

On success, this command returns

• SUCCESS
• INCOMPLETE

On failure, this command returns

• ERROR_OUT_OF_HOST_MEMORY
• ERROR_OUT_OF_DEVICE_MEMORY

Parameters

physicalDevice:VkPhysicalDevice

the physical device from which to query the set of calibrateable time domains.

pTimeDomainCount:IntBuffer

a pointer to an integer related to the number of calibrateable time domains available or queried, as described below.

pTimeDomains:IntBuffer

either NULL or a pointer to an array of VkTimeDomainEXT values, indicating the supported calibrateable time domains.

Annotations

@NativeType:VkResult

Array version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT

Annotations

@NativeType:VkResult