This renderer merges (or unions/dissolves) the line or polygon features
from a layer prior to rendering them. It's useful for rendering
a polygon layer with overlapping features as one single "coverage" feature,
or a line layer consisting of many smaller component line features
using a regularly spaced marker line or similar.
Internally, this just moves the guts of the existing inverted polygons
renderer to a new base class, as that renderer already had an option
to merge features prior to rendering. Basically it just exposes a new
renderer to users which is the inverted polygon renderer without
the inversion step!
and use this to determine whether a legend item needs updating
as a result of a map change
This results in a HUGE speed up when loading large projects where
symbols don't use Millimeter based sizes, as the previous code
assumed only that any non-millimeter size was a map unit based size.
While it was possible to set the opacity for individual symbol layer
colors via data defined expressions, it's so far been impossible to
set a data defined expression to control the overall symbol opacity.
This commit fixes that omission...
Any fill symbol layer which supports offsetting polygons (i.e. simple
fills, raster image fills, shapeburst and gradent fills) now allows
for data-defined offsets
in simple line symbol layers
New options are:
- Align dash pattern to line length: If checked, the dash pattern lengths
will be subtely adjusted in order to ensure that when a line is rendered
it will end with a complete dash element, instead of a gap element or
partial dash element
- Tweak dash pattern at sharp corners: If checked, this option dynamically
adjusts the dash pattern placement so that sharp corners are represented
by a full dash element coming into and out of the sharp corner. It's designed
to better represent the underlying geometry while rendering dashed lines,
especially for jagged lines
by a preset amount
Allows for tweaking the positioning of dashes/spaces in the line, so
that the dashes/spaces can be placed at nicer positions to account
for corners in the line (also can be used potentially to "align"
adjacent dash pattern borders)
Offset can be set in different units, including map units, and can
be data defined
