artemp/mapnik — Issue #870: Label cache
Author: artemp
Created: 2011-10-11 16:39:43+00:00
State: open
Labels: Core_Library

Currently, to ensure labels are placed on top of maps, separate layers are usually used.

This can be an optimization in some cases where features that should be rendered may be a very different set than those that should be labeled.

But, in cases like roads where lines features are both rendered visually and labeled, adding a label cache may provide a speed up to avoid the i/o impact of hitting the datasource more than once.

This could work by collecting, and caching all features that have matching text symbolizers, and rendering them after all other passes.