Add cmake install target

[theoparis]

Description

Currently it seems like the makefile is used for the install target even though ninja is used via cmake in the makefile.
I think it would make more sense to add a cmake install target so that you can do this:

cmake -B build -G Ninja
cmake --build build
sudo cmake --install build

This would also benefit the use case of customizing cmake features such as -DNO_XWAYLAND=ON or -DCMAKE_BUILD_TYPE=MinSizeRel without having to modify the makefile. This also impacts setting custom compilers and/or compiler flags.

[vaxerski]

the problem is install isn't that easy, as we for example use cpio which I don't think cmake has an equivalent.

[cnt0]

I guess this is about the installheaders. @vaxerski what you're trying to do with cpio? Keep symlinks? I'm pretty sure cmake has such options in at least some commands, might take a look

[vaxerski]

feel free to MR

[fufexan]

I've worked on porting most of the stuff from the Makefile to CMake, and it works fine, except in the Nix build, where CMake seems to build Hyprland twice for some reason. https://github.com/hyprwm/Hyprland/tree/cmake

[fufexan]

#5667 please test this.