public static TextureCubeMap createIrradianceMap(int size, Image.Format imageFormat) {

        TextureCubeMap irrMap = new TextureCubeMap(size, size, imageFormat);
        irrMap.setMagFilter(Texture.MagFilter.Bilinear);
        irrMap.setMinFilter(Texture.MinFilter.BilinearNoMipMaps);
        irrMap.getImage().setColorSpace(ColorSpace.Linear);
        return irrMap;
    }
initialize the irradiance map
@param size the size of the map
@param imageFormat the format of the image
@return the initialized Irradiance map
jme3-core/src/main/java/com/jme3/environment/util/EnvMapUtils.java