AiM 8.0 Quick Reference Guide Styled Layer Descriptor (SLD)

Transcription

1 AiM 8.0 Quick Reference Guide 2015 AssetWorks LLC 1777 NE Loop 410, Suite 1250 San Antonio, Texas (800)

2 TABLE OF CONTENTS INTRODUCTION... 3 SLD... 4 MODIFYING THE.SLD FILE... 4.SLD FILE STRUCTURE... 4 TYPES OF OBJECTS... 6 Point... 7 Line... 9 Polygons CONCLUSION LIST OF TABLES

3 INTRODUCTION The purpose of this document is to provide quick reference guide for modifying an existing Styled Layer Descriptor (SLD).XML file. This document will show how easily layers can be modified to better display GIS information. For instance, editing the.sld file enables users to change the color of a polygon fill or the font for textual information. This document does not provide a tutorial for adding attributes not currently specified, as this would require coding knowledge that is beyond the scope of this document. For more indepth information, consult the online help for the GIS server (e.g., the Geoserver online documentation is found here in the SLD Cookbook and the SLD Reference, respectively: and The examples in this document are found in the Geoserver SLD Cookbook. 3

4 SLD MODIFYING THE.SLD FILE The purpose of this document is to provide a working knowledge of the.sld file structure and the different vector types of objects (polygon, line, and point) to modify with examples of each. Raster objects are not covered in this document..sld FILE STRUCTURE The.SLD file is a compilation of GIS layer definitions. In order to modify this file, users must have an editor program to modify the.sld file (e.g., Crimson Editor), know the location of the.sld file (located in the Tomcat\webapps\root directory), and then the name of the layers to modify (some institutions have an.sld file that contains myriad entries making it difficult to find the layer). The GIS Viewer enables users to select the layers to display and thus determine the layer to modify. The names of the layers in the Layer Block of the GIS Viewer, correspond to the names of the layers in the.sld file. Each layer definition is marked with a beginning and end NamedLayer line. The actual name of the layer is the next line after the first NamedLayer line (<Name>). The example below shows a layer definition with the beginning and end of the definition highlighted (in this case, the layer name is geo:asw_planters): <NamedLayer> <Name>geo:ASW_PLANTERS</Name> <UserStyle> <Name>default</Name> <IsDefault>true</IsDefault> <FeatureTypeStyle> <Rule> <PolygonSymbolizer> <Fill> <CssParameter name="fill">#c4c2f2</cssparameter> <CssParameter name="fill-opacity">1</cssparameter> </Fill> <Stroke> 4

5 <CssParameter name="stroke">#000000</cssparameter> <CssParameter name="stroke-opacity">1</cssparameter> </Stroke> </PolygonSymbolizer> </Rule> </FeatureTypeStyle> </UserStyle> <UserStyle> <Name>selected</Name> <FeatureTypeStyle> <Rule> <PolygonSymbolizer> <Fill> <CssParameter name="fill">#ffff00</cssparameter> <CssParameter name="fill-opacity">1</cssparameter> </Fill> </PolygonSymbolizer> </Rule> </FeatureTypeStyle> </UserStyle> </NamedLayer> Note that the NamedLayer lines are indented farthest to the left. Indents take place as the definition drills into the different aspects of the objects (and always with a beginning and an end, except for lines containing the values to modify). These values are located to the far right of the lines. 5

6 TYPES OF OBJECTS Before discussing the differences of each of the objects, it is important to focus on the commonality that all the objects have, the ability to have a textual label of the object. The example below shows the beginning and end of the label definition (TextSymbolizer). Note the name of the label is easily identifiable (SmithLibrary) should the user want to modify the label. In addition, note the font and fill of the text are clearly identified. <TextSymbolizer> <Label> <ogc:propertyname>smithlibrary</ogc:propertyname> </Label> <Font> <CssParameter name="font-family">times New Roman</CssParameter> <CssParameter name="font-style">normal</cssparameter> <CssParameter name="font-size">12</cssparameter> </Font> <Fill> <CssParameter name="fill">#000000</cssparameter> <CssParameter name="fill-opacity">1</cssparameter> </Fill> </TextSymbolizer> Note: To turn off the text for the SmithLibrary label, look for the section in the.xml file that defines the TextSymbolizer. The section between these two lines contains the.xml code that creates and formats the text identification label names (i.e., Handles). Below is a method of commenting out the entire section to prevent the.xml code from executing. after the second <TextSymbolizer> line. Then save the file. The label is now commented out and will not appear in the GIS viewer. Insert a line above the first <TextSymbolizer> line and type <!-- and /--> 6

7 POINT Points are the simplest type of shape, possessing only position and no other dimensions, there are many ways to style a point in the.sld file. The style shown below is an example of a point style definition. It shows the beginning and end PointSymbolizer definition lines (highlighted). In addition, a complex common element, the TextSymbolizer (lines 12 through 38) is also displayed. 1 <PointSymbolizer> 2 <Graphic> 3 <Mark> 4 <WellKnownName>circle</WellKnownName> 5 <Fill> 6 <CssParameter name="fill">#ff0000</cssparameter> 7 </Fill> 8 </Mark> 9 <Size>6</Size> 10 </Graphic> 11 </PointSymbolizer> 12 <TextSymbolizer> 13 <Label> 14 <ogc:propertyname>smithlibrary</ogc:propertyname> 15 </Label> 16 <Font> 17 <CssParameter name="font-family">arial</cssparameter> 18 <CssParameter name="font-size">12</cssparameter> 19 <CssParameter name="font-style">normal</cssparameter> 20 <CssParameter name="font-weight">bold</cssparameter> 21 </Font> 7

8 22 <LabelPlacement> 23 <PointPlacement> 24 <AnchorPoint> 25 <AnchorPointX>0.5</AnchorPointX> 26 <AnchorPointY>0.0</AnchorPointY> 27 </AnchorPoint> 28 <Displacement> 29 <DisplacementX>0</DisplacementX> 30 <DisplacementY>25</DisplacementY> 31 </Displacement> 32 <Rotation>-45</Rotation> 33 </PointPlacement> 34 </LabelPlacement> 35 <Fill> 36 <CssParameter name="fill">#990099</cssparameter> 37 </Fill> 38 </TextSymbolizer> The following are examples associated with the point object example above: <WellKnownName> (Line 4) The <WelllKnownName> is the name of the common shape to render the object. The options are circle, square, triangle, star, cross, and x. The defaulted value is a square. Note the fill (in hexadecimal format) and size of the object is included. Objects may also be selected from an existing file as in the example below (although a full URL could be specified, no path information is necessary because this graphic is contained in the same directory as the.sld). In this example, the path is Tomcat/Webapps/Root/Shape directory (highlighted). The statement is between the two <Mark> lines. <Mark> <WellKnownName>shape://times</WellKnownName> 8

9 <Stroke> <CssParameter name="stroke">#990099</cssparameter> <CssParameter name="stroke-width">1</cssparameter> </Stroke> </Mark> <Font> (lines 16 through 21) The <Font> element specifies the font to be used for the label. A set of <CssParameter> elements specify the details of the font. Anchor Point (lines 24 through 27) Specifies the location within the label-bounding box that is aligned with the label point. The location is specified by <AnchorPointX> and <AnchorPointY> sub-elements, with values. Values may contain expressions. Displacement (lines 28 through 31) Specifies that the label point should be offset from the original point. The offset is specified by <DisplacementtX> and <DisplacementY> sub-elements, with values in pixels. Values may contain expressions. Rotation (line 32) Specifies the rotation of the label in clockwise degrees (negative values are counterclockwise). Value may contain expressions. The default value is zero. Fill (lines 35 through 37) The <Fill> element specifies the fill style for the label text. The syntax is identical to that of the PolygonSymbolizer <Fill> element. LINE A <LineSymbolizer> styles feature lines. Lines are one-dimensional geometries that have both position and length. Each line is comprised of one or more line segments, and has either two ends or none (if it is closed). In the example below is a line layer as defined between the <LineSymbolizer> lines (shown highlighted): 1 <NamedLayer> 2 <Name>RIVER_ROADS</Name> 9

10 3 <UserStyle> 4 <Name>RIVER_ROADS</Name> 5 <FeatureTypeStyle> 6 <Rule> 7 <LineSymbolizer> 8 <Stroke> 9 <CssParameter name="stroke">#552222</cssparameter> 10 <CssParameter name="stroke-opacity">1</cssparameter> 11 <CssParameter name="stroke-width">1</cssparameter> 12 </Stroke> 13 </LineSymbolizer> 14 </Rule> 15 </FeatureTypeStyle> 16 </UserStyle> 17 </NamedLayer> Stroke (lines 8 through 12) Lines in the.sld file have no notion of a fill, only stroke (i.e., edge). Thus, unlike points or polygons, it is not possible to style the edge of the line geometry. It is, however, possible to achieve this effect by drawing each line twice: once with a certain width and again with a slightly smaller width. This gives the illusion of fill and stroke by obscuring the larger lines everywhere except along the edges of the smaller lines. POLYGONS Polygons are two-dimensional shapes that contain both an outer edge (i.e., stroke) and an inside (i.e., fill). A polygon can be thought of as an irregularly shaped point and is styled in similar ways to points.. Every polygon contains one label point within its boundary. In addition, polygons have attributes that describe the geographic feature they represent. 1 <PolygonSymbolizer> 2 <Fill> 10

11 3 <CssParameter name="fill">#c4c2f2</cssparameter> 4 <CssParameter name="fill-opacity">1</cssparameter> 5 </Fill> 6 <Stroke> 7 <CssParameter name="stroke">#000000</cssparameter> 8 <CssParameter name="stroke-opacity">1</cssparameter> 9 </Stroke> 10 </PolygonSymbolizer> Fill (lines 2 through 5) The <Font> element specifies the font to be used for the label. A set of <CssParameter> elements specify the details of the font. Stroke (lines 6 through 9) Lines in the.sld file have no notion of a fill, only stroke (i.e., edge). Thus, unlike points or polygons, it is not possible to style the edge of the line geometry. It is, however, possible to achieve this effect by drawing each line twice: once with a certain width and again with a slightly smaller width. This gives the illusion of fill and stroke by obscuring the larger lines everywhere except along the edges of the smaller lines. Here is an example of managing the scale of the presentation. 1 <Rule> 2 <Name>Medium</Name> 3 <MinScaleDenominator> </MinScaleDenominator> 4 <MaxScaleDenominator> </MaxScaleDenominator> 5 <PolygonSymbolizer> 6 <Fill> 7 <CssParameter name="fill">#0000cc</cssparameter> 8 </Fill> 9 <Stroke> 10 <CssParameter name="stroke">#000000</cssparameter> 11

12 11 <CssParameter name="stroke-width">4</cssparameter> 12 </Stroke> 13 </PolygonSymbolizer> 14 </Rule> MinScaleDenominator/MaxScaleDenominator (lines 3 and 4) It is often desirable to make shapes larger at higher zoom levels when creating a natural-looking map. Zoom levels (or more accurately, scale denominators) refer to the scale of the map. A scale denominator of 10,000 means the map has a scale of 1:10,000 in the units of the map projection. This style contains three rules, defined as follows: TABLE 1: POLYGON SCALE DENOMINATOR RULES Rule Order Rule Name Scale Denominator Stroke Width Label Display? 1 Large 1:100,000,000 or less 7 Yes 2 Medium 1:100,000,000 to 1:200,000,000 4 No 3 Small Greater than 1:200,000,000 2 No The first rule is for the smallest scale denominator, corresponding to when the view is zoomed in. The scale rule is set such that the rule will apply only where the scale denominator is 100,000,000 or less. The second rule is for the intermediate scale denominators, corresponding to when the view is partially zoomed. The scale rules set the rule such that it will apply to any map with a scale denominator between 100,000,000 and 200,000,000. Note: The <MinScaleDenominator> is inclusive and the <MaxScaleDenominator> is exclusive. The third rule is for the largest scale denominator, corresponding to when the map is zoomed out. The scale rule is set such that the rule will apply to any map with a scale denominator of 200,000,000 or greater. The resulting style produces a polygon stroke that gets larger as one zooms in and labels that only display when zoomed in to a sufficient level. 12

13 Default Layer vs. Selected style This example illustrates how the default layer (which appears when the GIS Viewer is selected from the WorkDesk) is different from the selected style that displays when objects are retrieved from any other screen (e.g., Master Asset Profile or Property Profile Screens). In addition, the select layer is applied to search results when clicking the GIS Viewer Icon from a Browse Screen. The default layer (line 4) and the selected style (line 25) are highlighted. 1 <NamedLayer> 2 <Name>bldgs</Name> 3 <UserStyle> 4 <Name>default</Name> 5 <IsDefault>true</IsDefault> 6 <FeatureTypeStyle> 7 <Rule> 8 <PointSymbolizer> 9 <Graphic> 10 <Mark> 11 <WellKnownName>circle</WellKnownName> 12 <Fill> 13 <CssParameter name="fill">#cc0000</cssparameter> 14 <CssParameter name="fill-opacity">1</cssparameter> 15 </Fill> 16 </Mark> 17 <Opacity>1</Opacity> 18 <Size>8</Size> 19 </Graphic> 20 </PointSymbolizer> 13

14 21 </Rule> 22 </FeatureTypeStyle> 23 </UserStyle> 24 <UserStyle> 25 <Name>selected</Name> 26 <FeatureTypeStyle> 27 <Rule> 28 <PointSymbolizer> 29 <Graphic> 30 <Mark> 31 <WellKnownName>circle</WellKnownName> 32 <Fill> 33 <CssParameter name="fill">#ffff00</cssparameter> 34 <CssParameter name="fill-opacity">1</cssparameter> 35 </Fill> 36 </Mark> 37 <Opacity>1</Opacity> 38 <Size>16</Size> 39 </Graphic> 40 </PointSymbolizer> 41 </Rule> 42 </FeatureTypeStyle> 43 </UserStyle> 44 </NamedLayer> 14

15 Default layer (lines 4 through 20) This layer is the default layer for AiM entities as defined on the GIS Setup Screen, Default Layers Block. The default layer is the one displayed when users access the GIS Viewer from the WorkDesk. Selected style (lines 25 through 40) The selected style information is added to the.sld file to represent the layer turned on when an object is selected on screens other than the WorkDesk. When the GIS Viewer Icon is selected from a particular record, for instance from the Master Asset Profile Screen, the selected style is displayed for that particular record. When the GIS Viewer Icon is selected from a Browse Screen, all the retrieved records will be displayed with the selected style after clicking the GIS Viewer Icon. CONCLUSION The quick reference nature of this guide precludes an exhaustive discussion on how to code and the various ways to modify your GIS display and reporting. Please provide specific examples you would like to see in the guide. Please contact your Customer Service Representative for comments concerning improving this document. 15

16 LIST OF TABLES TABLE 1: POLYGON SCALE DENOMINATOR RULES