sphere2cube

sphere2cube is a Python script to map equirectangular (cylindrical projection, skysphere) map into 6 cube (cubemap, skybox) faces. See also cube2sphere.

Usage

$ sphere2cube -h
usage: sphere2cube [-h] [-v] [-r <size>] [-R <rx> <ry> <rz>] [-p <pattern>]
                   [-o <dir>] [-f <name>] [-b <path>] [-t <count>] [-V]
                   [<source>]

Maps an equirectangular (cylindrical projection, skysphere) map into 6 cube
(cubemap, skybox) faces.

positional arguments:
  <source>              source equirectangular image filename

optional arguments:
  -h, --help            show this help message and exit
  -v, --version         show program's version number and exit
  -r <size>, --resolution <size>
                        resolution for each generated cube face (defaults to 1024)
  -R <rx> <ry> <rz>, --rotation <rx> <ry> <rz>
                        rotation in degrees to apply before rendering cube
                        faces (z is up)
  -F <angle>, --fov <angle>
                        field of view of camera used for rendering cube faces
  -p <pattern>, --path <pattern>
                        filename pattern for rendered faces: default is
                        "face_%n_%r", where %n is replaced by the face number
                        and %r by the resolution
  -o <dir>, --output-dir <dir>
                        directory to save rendered faces to (it must already
                        exist)
  -f <name>, --format <name>
                        format to use when saving faces, i.e. "PNG" or "TGA"
  -b <path>, --blender-path <path>
                        filename of the Blender executable (defaults to
                        "blender")
  -t <count>, --threads <count>
                        number of threads to use when rendering (1-64)
  -V, --verbose         enable verbose logging

Supported output formats depend on the Blender installation, but will generally be TGA, IRIS, JPEG, MOVIE, IRIZ, RAWTGA, AVIRAW, AVIJPEG, PNG, BMP, and FRAMESERVER.

sphere2cube can be run in a headless environment (e.g., a server).

Examples

For instance, to render a 2048-resolution TGA cubemap from source.jpg, we could use the following command:

$ sphere2cube source.jpg -r2048 -fTGA

This would generate face_1_2048.tga, …, face_6_2048.tga in the working directory.

Installation

sphere2cube can be easily installed with pip. It requires a Python 3 installation, and at least Blender 2.8.

It assumes that Blender is installed and the blender executable is listed in the system PATH environment variable. If it is not possible for PATH to be edited (as in the case of an unprivileged user), the path to the blender executable may instead be passed through the -b flag.

Windows

Install Blender, and add blender.exe to PATH. Finally,

pip install sphere2cube

Linux

$ apt-get install blender
$ pip install sphere2cube

Mac OS X

Similar to Windows, install [Blender], and add the blender executable to $PATH. Then,

$ pip install sphere2cube