The floor before setting the transform ensures that we translate by integer pixels for odd and even dimenstions. The round before drawing the image ensures pixels are aligned.
Rendering performance degrades as the context lineWidth increases when calling lineTo many times for the same pixel coordinate. This appears to be a widespread performance issue and is very clearly improved by only calling lineTo when in a new pixel coordinate.
Vector events include features and extents. In the case of feature change events, the extents array will include old and new extents for features with modified geometries.w
With symbolizer literals now being geometry type specific, we no
longer need the overhead to query the RTree separately for each
geometry type and render symbolizer groups by geometry type.
The geometry type index of the FeatureCache is no longer needed.
The filtering functionality of the FeatureCache's
getFeaturesObject method can be removed because it is no longer
used.
Vector layers will now dispatch ol.layer.VectorLayerEventType.ADD and
ol.layer.VectorLayerEventType.REMOVE event types instead of the generic
goog.events.EventType.CHANGE event type.
This will fix a maximum call stack size exceeded javascript error.
Using the y-coordinate of the polygon's bounding box, this
simple algorithm intersects the polygon with the horizontal
center line of its bounding box. The x-coordinate of the label
point is the center of the longest segment of this intersection
that is inside the polygon.
Instead of just listening for the first change, we now listen
for all changes, and expire tiles by tile range. The outcome is
that the vector layer's addFeatures and removeFeatures methods
now show instant results on the rendered map.
With this change, getFeaturesObjectForExtent may return null if
the source does not have data loaded for the provided extent.
A callback can be passed to getFeaturesObjectForExtent to get
notified when the requested data is available.
The canvas vector layer still has the (API candidate) `getFeatures` method that accepts an arbitrary expression (was filter). This, and the `getFeaturesObject` method under it are only used in the tests. The rendering code that was using filters is now calling `layer.getFeaturesObjectForExtent` with an explicit extent and optional geometry type.
