- migrate to null safety
- add support external file
- add lighting
- fix some bugs
- fix texture & color mode
- add visiable & normalized & remove for object
- fix miss scene
- fix updateTexture not working
- rename mesh.image to mesh.texture
- update packingTexture to pack only different textures
- add interactive option to widget
- add face clipping
- add backface culling
- fix negative vertex problem
- inital release