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This module converts the horizontal coordinates of all geometry points — sources, receivers, and CMP/bin locations — from the New Zealand Map Grid (NZMG) projection to the New Zealand Transverse Mercator (NZTM) projection. The conversion applies a datum shift using an NTv2 ASCII grid correction file, which accounts for the difference between the geodetic datums underlying the two projections (NZGD49 to NZGD2000).
Use this module when your seismic survey geometry is stored in the legacy NZMG coordinate system and needs to be expressed in the modern NZTM system before further processing or integration with other data. The output geometry retains all original header information, with only the X/Y coordinate fields updated to reflect the new projection. Both the original and converted point locations are displayed on the map view for visual verification.
The seismic geometry dataset whose coordinates are to be converted. This item contains the full set of source points, receiver points, and CMP/bin points expressed in the NZMG coordinate system. All three point types are transformed: the module iterates over every source, receiver, and bin location independently and replaces each point's X and Y values with the corresponding NZTM coordinates.
The path to an NTv2-format ASCII grid shift file (extension .asc) that defines the datum transformation corrections to apply during coordinate conversion. This file encodes the latitude and longitude shifts required to move from the NZGD49 datum (used by NZMG) to the NZGD2000 datum (used by NZTM) at each location across New Zealand. The standard file distributed by Land Information New Zealand (LINZ) is commonly named nzgd2kgrid0005.asc. The module validates that the file is a well-formed NTv2 grid before applying any transformations; if the file cannot be parsed, the module returns an error and no coordinates are changed. Make sure the grid file covers the geographic extent of your survey area.
Selects whether the computation runs on the CPU or GPU. For coordinate conversion, the CPU option is generally sufficient as the workload is proportional to the number of geometry points, which is typically small.
Controls whether the job is submitted to a remote processing cluster. Enable this option to offload execution to available compute nodes in a distributed environment.
Specifies the minimum number of data units (gathers or traces) sent to each processing node in a single chunk during distributed execution. Larger values reduce scheduling overhead but may affect load balancing across nodes.
When enabled, restricts the number of parallel threads used on each remote processing node. This is useful when sharing compute resources with other jobs or when nodes have limited memory.
An optional text label appended to the job name when submitting to a distributed processing queue. Use this to distinguish parallel runs or to make job listings easier to identify in a cluster job manager.
When enabled, allows you to specify a custom CPU core affinity mask for the processing threads, overriding the system default. Enable this only if you need fine-grained control over which CPU cores are used, for example to avoid contention with other running processes.
Specifies the CPU core affinity mask to apply when Set custom affinity is enabled. The value is a bitmask where each bit corresponds to a logical CPU core. This setting has no effect when custom affinity is disabled.
Sets the number of parallel CPU threads used for processing. The default value is determined automatically based on the available hardware. For this module, the geometry conversion task is lightweight, so increasing the thread count beyond the default provides no significant benefit.
When enabled, this module is bypassed and its input data is passed through unchanged to the next step in the processing flow. Use this option to temporarily disable the coordinate conversion without removing the module from the workflow.
The updated geometry dataset in which the X and Y coordinates of all source points, receiver points, and CMP/bin locations have been replaced with their NZTM equivalents. All other trace header fields remain unchanged. The converted geometry is immediately available for downstream processing steps and is displayed on the map view alongside the original geometry for visual quality control.