Thin out repeated line labels at overscaled tiles #11414
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Prior to this change, the repeated line labels (such as street names) were placed too densely on overscaled tiles, sometimes even closer than the value of the `symbol-spacing` property. This caused a noticeable increase in memory usage, and the memory use increased dramatically with higher tiles overscale factors. This change partially mitigates the issue with the following changes: * for "very" overscaled tiles (overscale factor > 2) on high zoom levels (z > 18) we use the tile pixel ratio from the previous zoom level * the distance between too repeated line labels is never smaller than the `symbol-spacing` style property value (tile pixel ratio is clamped to 1)
ansis
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Prior to this change, the repeated line labels (such as street names) were placed too densely on overscaled tiles, sometimes even closer than the value of the
symbol-spacingproperty.This caused a noticeable increase in memory usage, and the memory use increased dramatically with higher tiles overscale factors.
This change partially mitigates the issue with the following changes:
symbol-spacingstyle property value (tile pixel ratio is clamped to 1)For example for
http://localhost:9966/debug#22/40.79230555/-73.9733581/33.4/67:memory usage before:
memory usage after:
So overall memory usage decreased from 75 MB to 26 MB, the amount of allocated objects decreased from 55694 to 21228
Launch Checklist
mapbox-gl-jschangelog:<changelog>Thin out repeated line labels at overscaled tiles in order to decrease memory and CPU usage</changelog>