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SRM Reference Manual
Functions SRM ConvergenceOfMeridian |
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| extern SRM_Status_Code | ||||
| SRM_ConvergenceOfMeridian | ||||
| ( | ||||
| const | SRM_SRF_Parameters_Pair | convert_params_ptr, | (notes) | |
| const | SRM_Coordinate | * | source_coord_ptr, | |
| SRM_Long_Float | * | dest_cosine_gamma, | (notes) | |
| SRM_Long_Float | * | dest_sine_gamma | (notes) | |
| ); | ||||
In general, a vector in a projected coordinate system must be rotated to account for the fact that meridians in such spatial reference frames are curved, and usually do not align with true north. More precisely, the rotation angle for transforming vectors must be determined. This angle is called the Convergence Of The Meridian (COM) in Geodesy.
| SRM_STAT_CODE_SUCCESS | and *dest_cosine_gamma, *dest_sine_gamma are set to the appropriate values, if valid parameters were passed in. |
| SRM_STAT_CODE_INVALID_DEST_COSINE_GAMMA | and the output parameter values are left unaltered, if dest_cosine_gamma is NULL. |
| SRM_STAT_CODE_INVALID_DEST_SINE_GAMMA | and the output parameter values are left unaltered, if dest_sine_gamma is NULL. |
| SRM_STAT_CODE_INVALID_SRF_PAIR | and the output parameter values are set to zero (0.0), if convert_params_ptr was NULL. |
| SRM_STAT_CODE_INVALID_SOURCE_COORD | and the output parameter values are set to zero (0.0), if source_coord_ptr is NULL or invalid and is required. |
| SRM_STAT_CODE_FAILURE | and the output parameters are each set to zero (0.0), if the underlying implementation has not yet been provided. $$$ |
the spatial reference frame (SRF) parameters of the source and destination SRFs
a pointer to where the cosine of gamma will be stored
a pointer to where the sine of gamma will be stored
Prev: SRM_ChangeCoordinateSRFUnvalidated.
Next: SRM_ConvertMatrix3x3.
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