A game asking for 960 x 540 got 960 x 540 pixels - a quarter of a 4K panel.
w_fit_scale turns the display's DPI into a whole-number scale (96 -> 1, 168 and
192 -> 2), brought down until the window fits; win_open and win_gl_resize size
the client area with it, win_gl_scale reports it the way cocoa.ll reports the
backing scale, and the mouse still arrives in the game's own units.
Verified on a 3840x2160 panel at 175%: windowed gl_triangle's 640x360 window
draws a 1280x720 frame.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>