Pcb_new and the footprint editor come in different flavors. These differ greatly in functionality and in their interface. (They are more like different versions of the same programs than different render engines.)
The options have the following names <KiCad 4.0.x> | KiCad 5.x
- <
default> |legacy - <
open gl> |modern (accelerated) - <
cairo> |modern (fallback)
The legacy canvas
The legacy canvas will be dropped in a future release. It is no longer developed. It is included because some features where still missing in the modern canvases when KiCad 4.0 has been released. For this reason the legacy canvas is the default canvas for the KiCad 4.0.x series.
Most of the missing features will be included in the modern canvases of KiCad 5.0. The legacy canvas will still be included for users who do not want to switch over and for users who still miss some minor feature that has still not been transferred over to the newer canvases.
The modern canvases
These are the actively developed canvases. They have been developed to support the interactive router and everything that depends on it. (The legacy canvas had performance issues which made a complete rewrite necessary.)
The accelerated version of this canvas does require that the graphics card (and it’s driver) support open gl 2.1 or newer. The fallback version does use software acceleration via cairo. If you have trouble running the accelerated version try to update your graphics card driver. If this does not solve your problems you can always switch back to the fallback canvas.
Switching canvases
Switching between canvases is done via the view menu in kicad 4.0.x and in some nightly versions. In kicad 5 and later nightlies this can be done via the preference menu. Or by using the keyboard shortcuts F9 for legacy, F11 for modern (accelerated) and F12 for modern (fallback)