How is the labeling of a polygon done in GeoServer?

How is the labeling of a polygon done in GeoServer?

Labeling of a polygon is anchored to the centroid of the polygon. GeoServer provides a vendor-option to allow labels to line wrap to remain within the polygon boundaries. For our Polygon exercises we will try and limit our CSS documents to a single rule, in order to showcase the properties used for rendering.

How does SLD describe the shape of a polygon?

SLD uses a PolygonSymbolizer to describe how the shape of a polygon is drawn. The primary characteristic documented is the Fill used to shade the polygon interior. The use of a Stroke to describe the polygon boundary is optional. Labeling of a polygon is anchored to the centroid of the polygon.

How is the simple feature used in GeoJSON?

The Simple Feature for SQL Geometry model (used by GeoJSON) represents these areas as Polygons, the ISO 19107 geometry model (used by GML3) represents these areas as Surfaces. SLD uses a PolygonSymbolizer to describe how the shape of a polygon is drawn.

Why is the label on the blue polygon?

I am trying to move a label’s position in order to show the blue polygon as pictured below. The label crosses other polygons (the blue polygon) that I must present in the map. The label is part of another polygon that I don’t show in the map and only show it label (number 3922).

How does the maxdisplacement option work in GeoServer?

The maxDisplacement option controls the displacement of the label along a line, around a point and inside a polygon. For lines, normally GeoServer labels a line at its center point only. If this label conflicts with another one it may not be displayed at all.

How are labels rotated in GeoServer 2.10.x?

Rotates the label clockwise by a given number of degrees. The best way to explain these options is with examples. The anchor point determines where the label is placed relative to the label point. The anchor point values—listed here as (X, Y) ordered pairs—are specified relative to the bounding box of the label, with values from 0 to 1 inclusive.

Where is the centroid of a polygon in GeoServer?

For lines, this point lies at the middle of the visible portion of the line. For polygons, the point is the centroid of the visible portion of the polygon. The position of the label relative to the label point can be controlled by the following sub-elements:

Are there SLD extensions for GeoServer 1.0?

The label placement optimizations discussed below (the tags) are SLD extensions that are custom to GeoServer. They are not part of the SLD 1.0 specification. This example is similar to the Polygon with default label example, with additional styling options within the on lines 12-35. Lines 16-21 set the font styling.

What does Line 8 do in GeoServer 2.19.x?

Line 8 specifies a “times” symbol (an “x”) be tiled throughout the polygon. Line 10 sets the color to purple ( #990099 ), line 11 sets the width of the hatches to 1 pixel, and line 14 sets the size of the tile to 16 pixels.

How to fill a polygon with color sampled from?

I want to symbolize the geometries in an SLD (PolygonSymbolizer) but fill it with a color value that is interpolated between BLUE-PURPLE-RED based on the rating value, in range -100 to +100. So the polygon would have a single fill color, but the color should be dynamic, based on the value.

Is there such a thing as a GeoServer gradient?

GeoServer provides a solution, but it is not called something with “gradient”. I hope this helps. Thanks for contributing an answer to Geographic Information Systems Stack Exchange! Please be sure to answer the question.

Why do we need getlegendgraphic call in GeoServer?

GeoServer allows building content dependent legend, that is, legends whose contents depend on the currently displayed map. In order to support it the GetLegendGraphic call needs the following extra parameters:

What are the parameters for legend _ options in GeoServer?

Here is a description of the various parameters that can be used in LEGEND_OPTIONS: fontName (string) the name of the font to be used when generating rule titles. The font must be available on the server fontStyle (string) can be set to italic or bold to control the text style.

How are graphic symbols rendered in a GeoServer?

Graphic symbols are rendered so that the center of the graphic extent lies on the placement point (or points, in the case of repeated or tiled graphics). If it is desired to have a graphic offset from a point (such as a symbol which acts as a pointer) it is necessary to offset the visible portion of the graphic within the overall extent.