From ed20821eb4de21cc3964eb72d82ea9ad8d810ab2 Mon Sep 17 00:00:00 2001 From: Even Rouault Date: Thu, 18 Apr 2019 11:06:34 +0200 Subject: Improve doc of proj_coordoperation_get_towgs84_values() (fixes #1430) --- src/iso19111/c_api.cpp | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/iso19111/c_api.cpp b/src/iso19111/c_api.cpp index 5df7458e..bd0fbc4f 100644 --- a/src/iso19111/c_api.cpp +++ b/src/iso19111/c_api.cpp @@ -5985,7 +5985,10 @@ int proj_coordoperation_get_param( * @param coordoperation Object of type Transformation, that can be represented * as a WKT1 TOWGS84 node (must not be NULL) * @param out_values Pointer to an array of value_count double values. - * @param value_count Size of out_values array. + * @param value_count Size of out_values array. The suggested size is 7 to get + * translation, rotation and scale difference parameters. Rotation and scale + * difference terms might be zero if the transformation only includes translation + * parameters. In that case, value_count could be set to 3. * @param emit_error_if_incompatible Boolean to inicate if an error must be * logged if coordoperation is not compatible with a WKT1 TOWGS84 * representation. -- cgit v1.2.3