Zooming in showed the ghost, then a black screen, then the map drawn in. The
black was a raster started the moment the view changed, before the new tile
zoom's tiles had loaded. It had nothing to draw, and being the view's own
frame it replaced the ghost. On the PicoCalc it stayed up 0.4 to 1.0 s, and
sometimes a half-drawn frame followed it before the real one. The same
happened when the map first opened.
The map now starts no raster while a tile of its view is still on its way.
It keeps standing on what it has (the aligned frame, or the ghost), and the
first raster it draws is the real picture. A tile that comes back as silence
is no longer on its way, so a map with no network still draws what it can.
Measured with a zoom tour on the PicoCalc: in to z11, z12 and z13, then back
out to z10. Before, every zoom across a tile zoom published a raster with
none of its tiles. Now each zoom draws one raster with all of them. The
finished picture arrives as soon as it did before (0.8 to 1.35 s in, 0.4 to
0.7 s out), with 6 rasters drawn instead of 13.
Tests that exercised raster scheduling now let their tiles answer first,
since a captured load used to stay on its way for ever.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Jean-Pierre MartineauandClaude Opus 5.5
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