panorama2cubemap

This project has been tested on:

macOS 12.4 Monterey

XCode 13.4.1

code from https://stackoverflow.com/a/34720686/2482283

other implement:

c++ without dependency: https://github.com/chinhsuanwu/360-converter

python: https://github.com/sunset1995/py360convert

imagemagick script: http://www.fmwconcepts.com/imagemagick/sphericalpano2cube/index.php

online test tools

https://shakthijuego.github.io/skybox-viewer/dist/index.html

interface

bool pano2cube(std::string inpath, std::vector<std::string>& outpaths, int width = -1, std::string mergedPath = "");

outpaths 6 face order: +X, -X, +Y, -Y, +Z, -Z

+X right
-X left
+Y top 
-Y bottom
+Z front
-Z back

correspond to OpenGL define:

GL_TEXTURE_CUBE_MAP_POSITIVE_X
GL_TEXTURE_CUBE_MAP_NEGATIVE_X
GL_TEXTURE_CUBE_MAP_POSITIVE_Y
GL_TEXTURE_CUBE_MAP_NEGATIVE_Y
GL_TEXTURE_CUBE_MAP_POSITIVE_Z
GL_TEXTURE_CUBE_MAP_NEGATIVE_Z 

build test code

require install opencv first, for macos:

brew install opencv

build, the test code at the tail of the cpp file

mkdir build && cd build
cmake ..
make -j12

run command:

./pano2cube ../src/auto_stop_spherical_pano.jpg

generate:

../src/auto_stop_spherical_pano0.png
../src/auto_stop_spherical_pano1.png
../src/auto_stop_spherical_pano2.png
../src/auto_stop_spherical_pano3.png
../src/auto_stop_spherical_pano4.png
../src/auto_stop_spherical_pano5.png

test result

there is test code in the file, read auto_stop_spherical_pano.jpg and generate 6 faces.

test image:

generated image is:

src/auto_stop_spherical_pano0.png
src/auto_stop_spherical_pano1.png
src/auto_stop_spherical_pano2.png
src/auto_stop_spherical_pano3.png
src/auto_stop_spherical_pano4.png
src/auto_stop_spherical_pano5.png

a correct result can be found in:

src/correct_result/auto_stop_spherical_pano0.png
src/correct_result/auto_stop_spherical_pano1.png
src/correct_result/auto_stop_spherical_pano2.png
src/correct_result/auto_stop_spherical_pano3.png
src/correct_result/auto_stop_spherical_pano4.png
src/correct_result/auto_stop_spherical_pano5.png

left

front

right

back

top

bottom

Acknowledgements

The code for converting an equirectangular panorama to a cube map was taken from this stackoverflow answer.