public void setPixel(Vector3f vector, ColorRGBA color) {

        int face = EnvMapUtils.getCubemapFaceTexCoordFromVector(vector, sizes[0], uvs, EnvMapUtils.FixSeamsMethod.Stretch);
        raster.setSlice(face);
        raster.setPixel((int) uvs.x, (int) uvs.y, color);
    }
writes a pixel given the coordinates vector and the color.
@param vector the coordinates where to write the pixel
@param color the color to write
jme3-core/src/main/java/com/jme3/environment/util/CubeMapWrapper.java