Stud.io and LDD both run well under Wine. However it's good to have an alternative tool that is open source. Stud.io uses the LDraw part database, the same as LeoCAD.
There's also blueprint, a tool to design LEGO instructions. It's not open source due to the author's legal concerns about publishing an open source library to read LEGO's own part database. It's a pity because it is a great tool, with a very good UI. LDraw files (.ldr) support instructions, but the user interface is a bit harder to use compared to the more specialized one in blueprint.
There's also blueprint, a tool to design LEGO instructions. It's not open source due to the author's legal concerns about publishing an open source library to read LEGO's own part database. It's a pity because it is a great tool, with a very good UI. LDraw files (.ldr) support instructions, but the user interface is a bit harder to use compared to the more specialized one in blueprint.