org.lwjgl.vulkan

Class EXTCalibratedTimestamps

java.lang.Object

org.lwjgl.vulkan.EXTCalibratedTimestamps

public class EXTCalibratedTimestamps
extends java.lang.Object

This extension provides an interface to query calibrated timestamps obtained quasi simultaneously from two time domains.

Name String

VK_EXT_calibrated_timestamps

Extension Type

Device extension

Registered Extension Number

185

Revision

1

Extension and Version Dependencies

• Requires Vulkan 1.0

Contact

• Daniel Rakos drakos-amd

Last Modified Date

2018-10-04

IP Status

No known IP claims.

Contributors

• Matthaeus G. Chajdas, AMD
• Alan Harrison, AMD
• Derrick Owens, AMD
• Daniel Rakos, AMD
• Jason Ekstrand, Intel
• Keith Packard, Valve

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	VK_EXT_CALIBRATED_TIMESTAMPS_EXTENSION_NAME The extension name.
static int	VK_EXT_CALIBRATED_TIMESTAMPS_SPEC_VERSION The extension specification version.
static int	VK_STRUCTURE_TYPE_CALIBRATED_TIMESTAMP_INFO_EXT Extends VkStructureType.
static int	VK_TIME_DOMAIN_CLOCK_MONOTONIC_EXT VkTimeDomainEXT - Supported time domains
static int	VK_TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT VkTimeDomainEXT - Supported time domains
static int	VK_TIME_DOMAIN_DEVICE_EXT VkTimeDomainEXT - Supported time domains
static int	VK_TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT VkTimeDomainEXT - Supported time domains

Method Summary

Modifier and Type	Method and Description
static int	nvkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device, int timestampCount, long pTimestampInfos, long pTimestamps, long pMaxDeviation) Unsafe version of: GetCalibratedTimestampsEXT
static int	nvkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice, long pTimeDomainCount, long pTimeDomains) Unsafe version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT
static int	vkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device, VkCalibratedTimestampInfoEXT.Buffer pTimestampInfos, long[] pTimestamps, long[] pMaxDeviation) Array version of: GetCalibratedTimestampsEXT
static int	vkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device, VkCalibratedTimestampInfoEXT.Buffer pTimestampInfos, java.nio.LongBuffer pTimestamps, java.nio.LongBuffer pMaxDeviation) Query calibrated timestamps.
static int	vkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice, int[] pTimeDomainCount, int[] pTimeDomains) Array version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT
static int	vkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice, java.nio.IntBuffer pTimeDomainCount, java.nio.IntBuffer pTimeDomains) Query calibrateable time domains.

Methods inherited from class java.lang.Object

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

Field Detail

VK_EXT_CALIBRATED_TIMESTAMPS_SPEC_VERSION

public static final int VK_EXT_CALIBRATED_TIMESTAMPS_SPEC_VERSION

The extension specification version.

See Also:

Constant Field Values

VK_EXT_CALIBRATED_TIMESTAMPS_EXTENSION_NAME

public static final java.lang.String VK_EXT_CALIBRATED_TIMESTAMPS_EXTENSION_NAME

The extension name.

See Also:

Constant Field Values

VK_STRUCTURE_TYPE_CALIBRATED_TIMESTAMP_INFO_EXT

public static final int VK_STRUCTURE_TYPE_CALIBRATED_TIMESTAMP_INFO_EXT

Extends VkStructureType.

See Also:

Constant Field Values

VK_TIME_DOMAIN_DEVICE_EXT

public static final int VK_TIME_DOMAIN_DEVICE_EXT

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 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

See Also:

Constant Field Values

VK_TIME_DOMAIN_CLOCK_MONOTONIC_EXT

public static final int VK_TIME_DOMAIN_CLOCK_MONOTONIC_EXT

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 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

See Also:

Constant Field Values

VK_TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT

public static final int VK_TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT

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 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

See Also:

Constant Field Values

VK_TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT

public static final int VK_TIME_DOMAIN_QUERY_PERFORMANCE_COUNTER_EXT

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 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

See Also:

Constant Field Values

Method Detail

nvkGetPhysicalDeviceCalibrateableTimeDomainsEXT

public static int nvkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice,
                                                                  long pTimeDomainCount,
                                                                  long pTimeDomains)

Unsafe version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT

Parameters:

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

vkGetPhysicalDeviceCalibrateableTimeDomainsEXT

public static int vkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice,
                                                                 java.nio.IntBuffer pTimeDomainCount,
                                                                 @Nullable
                                                                 java.nio.IntBuffer pTimeDomains)

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. If pTimeDomainCount is smaller than the number of calibrateable time domains supported for the given physicalDevice, INCOMPLETE will be returned instead of SUCCESS to indicate that not all the available values 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 - the physical device from which to query the set of calibrateable time domains.

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

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

nvkGetCalibratedTimestampsEXT

public static int nvkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device,
                                                int timestampCount,
                                                long pTimestampInfos,
                                                long pTimestamps,
                                                long pMaxDeviation)

Unsafe version of: GetCalibratedTimestampsEXT

Parameters:

timestampCount - the number of timestamps to query.

vkGetCalibratedTimestampsEXT

public static int vkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device,
                                               VkCalibratedTimestampInfoEXT.Buffer pTimestampInfos,
                                               java.nio.LongBuffer pTimestamps,
                                               java.nio.LongBuffer pMaxDeviation)

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

Note

The maximum deviation may vary between calls to vkGetCalibratedTimestampsEXT even for the same set of time domains due to implementation and platform specific reasons. It is the application's responsibility to assess whether the returned maximum deviation makes the timestamp values suitable for any particular purpose and can choose to re-issue the timestamp calibration call pursuing a lower devation value.

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 - the logical device used to perform the query.

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

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

pMaxDeviation - 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.

vkGetPhysicalDeviceCalibrateableTimeDomainsEXT

public static int vkGetPhysicalDeviceCalibrateableTimeDomainsEXT(org.lwjgl.vulkan.VkPhysicalDevice physicalDevice,
                                                                 int[] pTimeDomainCount,
                                                                 @Nullable
                                                                 int[] pTimeDomains)

Array version of: GetPhysicalDeviceCalibrateableTimeDomainsEXT

vkGetCalibratedTimestampsEXT

public static int vkGetCalibratedTimestampsEXT(org.lwjgl.vulkan.VkDevice device,
                                               VkCalibratedTimestampInfoEXT.Buffer pTimestampInfos,
                                               long[] pTimestamps,
                                               long[] pMaxDeviation)

Array version of: GetCalibratedTimestampsEXT