Recently, I’ve tried exporting my built lightmaps as several formats, tga, hdr, bmp, pcx etc. What happened is that when i imported those lightmaps back into unreal engine 4.15, some lighting data goes wrong. Some subtle lighting information was lost or even the engine crashed when exporting as tga and hdr format respectively. As for bmp, pcx and other formats, the lighting information went totally incorrect.
So I wonder if there’s a proper format to export my lightmaps as, in order to keep the lighting information completely correct when importing back? Thanks a lot 