[core] Avoid clipping symbols in continuous mode

[brunoabinader]

Re-enable symbol clipping based on layout property settings, cleaning up workarounds and adds padding to symbol annotation tiles.

Avoid clipping symbols in continuous mode - preserving clipping behavior in still mode. To avoid overdrawing symbols on tile edges, we avoid inserting symbol features with anchors located among the tile extent edges.

Fixes #1673 and #6670.

/cc @jfirebaugh @ansis

[mention-bot]

@brunoabinader, thanks for your PR! By analyzing the history of the files in this pull request, we identified @jfirebaugh, @mikemorris and @ansis to be potential reviewers.

[jfirebaugh]

Can you comment on #6670 (comment) and help fill in the gaps in my understanding?

[brunoabinader]

Can you comment on #6670 (comment) and help fill in the gaps in my understanding?

I've added an extensive introspection as a comment in #6670.

[jfirebaugh]

I don't see how removing mode == MapMode::Still here is safe. In still mode, rendering a single tile, we cannot throw away features in the tile buffer under any circumstances, for the reasons detailed in #6670 (comment).

[brunoabinader]

You are right - for Still mode we need to render all features.

[brunoabinader]

Per #6670 (comment) - it seems we no longer need padding for symbol annotations - we can sort symbol render tiles instead prior to rendering.

We still clip in still mode, but just because we need to update our render test results. I'm deferring this work to a following PR.

[brunoabinader]

Based on @jfirebaugh's comments, I'm going to revert a few comments about clipping symbols for Still mode I've had removed on this PR. Will flag it reviewable again once it is finished.

[brunoabinader]

Ready for review.

[brunoabinader]

@jfirebaugh @ansis I have cleaned up the patches from this PR, removing stuff that was not related to the proposed changes:

• Avoid clipping symbols in continuous mode - preserving clipping behavior in still mode. We alleviate the rendering artifacts mentioned in add padding to annotation tiles #1673 by sorting render tiles in reverse Y prior to rendering.
• To avoid overdrawing symbols on tile edges, we avoid inserting symbol features with anchors located among the tile extent edges - fixes Annotation symbols are overdrawn if located on tile edges #6670.