Jeroen: 'still not filling the screen... maybe we should calculate the depth
that needs to be invented based on the canvas size somehow.' That is the fix.
The old flow picked cells from the viewport, let the SERVER impose Global's
2:1 aspect, then fitted the returned extent into the drawable area with an
INTEGER pixels-per-gridunit ratio. When that extent did not divide the area
evenly, floor() dropped a whole step — and at ratio 2 the only step below is
1, i.e. half size. Worse, because the client fitted an extent it had not
chosen, the result could fill NEITHER axis.
Inverted: global_fill_extent() chooses the cell count FROM the ratio, already
shaped 2:1, so cells * RATIO is the drawn size by construction and lands
exactly on the binding axis. Verified across window shapes — 1920x1080 fills
width, 2560x1080 fills height, 2560x1440 width, 3440x1440 height, 1280x720
width. Exactly one axis fills at every shape, which is the most a 2:1
equirectangular canvas can do in an arbitrary viewport; the other letterboxes.
Global keeps its 2:1 aspect because it is 360 degrees of longitude by 180 of
latitude — the aspect cannot follow the viewport without shearing the map.
Tests pin the invariant directly: 2:1 preserved, never overflowing the
drawable area, and never leaving slack on BOTH axes.
Client suite 1832 / 1806 passed / 0 failed / 26 skipped.
Co-Authored-By: Claude <noreply@anthropic.com>
jpmschweitzerandClaude
144d35d2a5