HOTINE OBLIQUE MERCATOR MAP PROJECTION IN PROJ4JS LIBRARY
The implementation of GIS application using hybrid approach on smartphone should have a coordinate transformation capability from one coordinate system into another. One of the available libraries to handle a coordinate transformation is Proj4JS. Unfortunately, this library is not able to perform coordinate transformation from Hotine Oblique Mercator into other projection. One example of this projection is Kertau (RSO) / RSO Malaya (m). We proposed new approach that introduce new formula, algorithm, Proj4JS definition and involve datum transformation to enable the coordinate transformation from Hotine Oblique Mercator into another coordinate system or vice versa. Using the proposed approach, all the features are rendered on top the feature that rendered using Spherical Mercator projection. We compare the result also with the Google Map. It shows that all features are properly rendered on top of Google Map features.