• Vector
• Legend types
• Introduction
• Quantities
• Categories
• Multiple attributes
• Quantity by category
• Pie legend
• Introduction
• Display and selection of pie charts
• Chart size options
• Draw pie charts for selected geometries only
• Bar legend
• Display and selection of bar charts
• Chart size options
• Draw bar charts for selected geometries only
• Objects
• Saving and recovering legends
• Modify symbols
• Introduction
• Symbol editor
• Introduction
• Marker or specific symbol
• Lines or linear symbols
• Fills for polygon symbols
• Symbol levels
• Labels that show in ToC
• Library of Symbols

Vector

Legend types

Introduction

In this tab you can define, in an advanced manner, the type of legend with which you want to represent the data of layer, from its fields [1].

[1]: It must be noted that you can not use the fields resulting from a join to make legend classifications, meaning that, to use these fields in a legend you will have to export the shp resulting from the join.

You can choose the following forms of representation:

Quantities

Four types of legends can be found:

Categories

Expressions

Shows layer elements according to a certain filtered expression.

• ''New filtered expression:'' A new window opens where you can configure expressions (filters) upon which a certain symbol will be applied. Each of these will be shown as a row in the main window of this type of legend. The syntax these filters use is SLD.
• ''Modification of filtered expression:''You are able to modify an expression by selecting it.
• ''Delete a filtered expression:''You are able to delete an expression by selecting it.
• ''Up/Down buttons:'' Allows you to move the created expressions up or down so that they later have that order in ToC.

Unique values

Each register can be represented with an exclusive symbol according to the value it adopts in a certain field in the attributes table. It is the most efficient method for spreading categorical data, such as municipalities, floor types, etc.

You will find the following symbology configuration options:

• ''Classification field:''A drop-down menu opens where you can select the layer which contains the data to carry out the classification, in the attributes table field.
• ''Add all/Add:'' Once the “classification field” is selected, all the different values are shown by assigning a symbol (colour) different to each by clicking on the “Add All” button. These symbols can be modified by clicking on them. By default the label (name that appears on the legend) is similar to the value that is adopted by this field. By clicking on “Add” you can add new values to the list.
• ''Delete all/Delete:'' Allows you to delete all (delete all) or some (delete) of the elements that make up the legend.
• ''Symbol properties:'' If you right click on any of the “cells” on the “Symbols” you can modify its properties specifically through the “Select symbol” and “Symbology level” buttons, as well as being able to change the label name in TOC.

Multiple attributes

Category quantities

Represents quantities for each category.

For this, it combines two fields (which must be of a numeric type), applying a combined legend made up of colour ramp (for field_1) and specific gradual symbols (for field_2).

Meaning that this type of legend combines a a representation of intervals based on the values of Field_1 with anothier representation of gradual symbols based on the values of field_2.

Chart or diagram legends are intended to provide a visual representation of data in a table, thereby communicating a lot of information very easily.

In particular this extension allows two types of legends to be constructed:

• The first one is represented by circular diagrams known as Pie Charts. The pie chart shows the proportional size of the elements of a data series, based on the sum of its parts, and with each sector representing the value of a particular field. It always shows only one data series and is useful when you want to emphasize a significant element.
• The second type of legend is represented by diagrams known as Bar Charts or Bar Graphs. A bar graph, also known as a column graph, is a diagram containing rectangular bars with lengths proportional to the values ​​they represent. Bar graphs are used to compare two or more values.

The pie legend is located in the Multiple attributes section of the legend tree, and can be used to represent several attributes at once. To access it, right-click on the layer name to open the Properties and then select the symbols tab.

The following options are available for configuring the pie charts:

Symbols. Pie legend

Fields: You can choose which of the layer's fields to represent, provided they are numeric. With these fields you can:

• Add all fields.
• Delete all fields.
• Add the selected fields.
• Delete the selected fields.

To do this click on the buttons shown in the image above (Box 1).

Colour scheme: You can change the default colour scheme for the pies. To do this select the desired "Colour scheme" from the drop-down list, as shown in the image above (Box 2).

Change the colour: In addition it is possible to change the colour of pie slices once they have been added.

Once the default colour scheme has been chosen, the colour of a pie slice can be changed by double-clicking on its color.

The following dialog is displayed where you can select a colour sample or set it yourself (HSB, RGB).

Symbols. Color Selection

Background symbol: You can change the symbol of the background geometries by clicking on the symbol to open the symbol editor (pictured above, Box 3).

Symbols. Symbol Selector

Outline: You can display an outline with a specified colour and thickness around the pie slices. Tick the "Show" check box to draw outlines around the pie sectors.

Dimension: Tick the check box to display the pie in 3D. By default the pie is drawn in 2D.

Preview chart: Any changes made are reflected on the chart preview.

Click the 'Size' button located in the pie legend configuration screen.

Pie Legend. Size button

Clicking this will open the following dialog:

Pie Legend. Configuring size

There are three options for setting the size of the diagrams:

• Fixed Size: All the pie charts will have the size indicated here.
• Sum of field values: The size of the pie charts is obtained from the sum of all the records of the fields making up the chart.
• Field size: The size is obtained from the selected field and can be normalized if so desired.

In addition to setting the size of the pie, the units can also be specified.

Units: Select units (meters, pixels ...) and representation (in the world or print layout), depending on your requirements. If the units are set to "in the world" then the size will depend on the View's zoom level, while selecting "print layout" results in a fixed size, both on the screen and when printed.

Active Limits: Limits can be specified if the size of the chosen field size is not set to the "Fixed Size" option.

Activating limits for the other options sets the minimum and maximum values of a particular measure (Sum of field values or Field size). Taking the limits into account, the intermediate field values are calculated in proportion to the values ​​of the records of the field, or to the sum of the field values.

This option is used to restrict the drawing of pie charts to selected geometries.

The geometries can be selected either before or after configuring the pie chart size and display options.

In order to represent pie charts for selected geometries, simply activate the check box Draw only selection in the pie legend configuration dialog.

Check to display pie charts for selected geometries only

The following image shows an example in which pie charts are only shown for selected geometries (shown in yellow).

Example showing pie charts for selected geometries

The bar legend is located the Multiple Attributes section of the legend tree, and can be used to represent several attributes at once. To access it, right-click on the layer name to open the Properties, then select the Symbols tab.

The following options are available for configuring bar charts:

Symbols. Legend bar

Fields: You can choose which of the layer's fields to represent, provided they are numeric. With these fields you can:

• Add all fields.
• Delete all fields.
• Add the selected fields.
• Delete the selected fields.

To do this click on the buttons shown in the image above (Box 1).

Colour scheme: You can change the default colour scheme for the bars. To do this, select the desired "Colour scheme" from the drop-down list, as shown in the image above (Box 2).

Change the colour: In addition it is possible to change the colour of bars once they have been added.

Once the default colour scheme has been chosen, the colour of a bar can be changed by double-clicking on its color tile.

You can use the following dialog to select a colour sample, or set it yourself (HSB, RGB).

Symbols. Color Selection

Background symbol: You can change the symbol of the background geometries by clicking on the symbol to open the symbol editor (pictured above, Box 3).

Symbols. Symbol Selector

Outline: You can display an outline with a specified colour and thickness around the bars. Tick the "Show" check box to draw outlines around the bars.

Dimension: Tick the check box to display the bars in 3D. By default the bars are drawn in 2D.

Preview chart: Any changes made are reflected on the chart preview.

Click the 'Size' button located in the bar legend configuration screen.

Bar Legend. Size button

Clicking this will open the following dialog:

Bar Legend. Configuring size

There are three options for setting the size of the diagrams:

• Fixed Size: The largest bar will drawn to this size, and the rest will be drawn proportionately.
• Sum of field values: The size of the bars will be determined by the sum of all the records in the fields making up the chart.
• Field size: The size is obtained from the selected field and can be normalized if so desired. For example, a chart could be drawn to represent the number of votes for each political party by the size of the bar, while the overall size of the diagram could be determined by another field, such as number of habitants. In this example, the size of the graph would be larger for areas of greater population.

In addition to setting the size of the bars, the units can also be specified.

Units: Select units (meters, pixels ...) and representation (in the world or print layout), depending on your requirements. If the units are set to "in the world" then the size will depend on the View's zoom level, while selecting "print layout" results in a fixed size, both on the screen and when printed.

Active Limits: Limits can be specified if the size of the chosen field size is not set to the "Fixed Size" option.

Activating limits for the other options sets the minimum and maximum values of a particular measure (Sum of field values or Field size). Taking the limits into account, the intermediate field values are calculated in proportion to the values of the records of the field, or to the sum of the field values.

This option is used to restrict the drawing of bar charts to selected geometries.

The geometries can be selected either before or after configuring the bar chart size and display options.

In order to display bar charts for selected geometries, simply tick the check box “Draw only selection” in the pie legend configuration dialog.

Check to display bar charts for selected geometries only

The following image shows an example in which bar charts are only shown for selected geometries (shown in yellow).

Example showing bar charts for selected geometries

Objects

Unique symbol

This is the default gvSIG legend type.

Represents all the elements of a layer using the same symbols. It is useful for when you need to show the location of a layer more than its any other attribute. The representation of its symbology depends on the type of geometry, this is further explained in the symbols section.

Saving and recovering legends

Save legend:

The legends that have been created can be saved so that you can use them on other occasions.

To save, click on the “Save legend” button.

A window will open with the save options: save legend with gvSIV (.gvl) format or standard exchange .sld format (currently supports SDL 1.0.0).

Legend recovery:

Legends that have been previously created can be recovered at any time. Click on the “Recover legend button” and select the legend you want to recover.

Modify symbols

Introduction

The Symbols tab is used to define advanced features of the legend being worked with.

When creating symbols for a legend it is important point to bear in mind the type of layer the symbols are being created for. This is important because there are two different types of vector layers to consider when making the symbols:

• Single geometry layers: (point, line or polygon shp layers). In this case the Symbols tab allows you to create or edit symbology relevant to the geometry (lines, points or polygons), as shown below:

Single geometry layer

• Multigeometry vector layers, such as dxf, dwg, gml ...

Multigeometry layer

In this case, there is a single Symbols tab where you can configure the symbol properties of the points, lines and polygons separately. Points are configured under the Marker tab, lines under the Line tab, and polygons under the Fill tab.

Tabs corresponding to the symbols for multigeometry layers

With this clarified, we can now look at symbol properties while taking the geometry type into account.

Symbol editor

From the layer menu, in properties, you can access the Symbology section. It is possible to change or configure a new symbol clicking on “Select symbol” where you will find different configuration options.

Click on the “Select symbol” button and then on the “Properties” button. The window which opens will allow you to edit the properties of the symbol. This is the same window that will open if you click on “New”.

By default gvSIG symbolises the layers with 'unique symbols'.

As well as the basic options that can been seen at first glance, such as colour, breadth and the type of units in which the symbol is to be represented, you can also edit the properties of the element. Next a classification of the properties of an element is made according to its geometry type.

The dialogue boxes that open have common sections and others that are specific to the type of geometry, we see them as follows:

Common characteristics:

When a symbol, is configured from its Properties, be it a point, a line or a polygon, it can be defined:

• Its colour and transparency. Allows the fill-in colour to be chosen.

Under colour you find a scrolling bar, which allows you to play with the grade of the transparency of the elements. This way, you can superimpose polygon layers without interfering with its display.

• The breadth of the symbol. Allows you to define the breadth of the element.
• Units: In this drop-down menu you can chose the type of unit which you want the symbol to be represented in. By default the unit which the symbol will be represented in are pixels, although you can chose between: Kilometers, meters, centimeters, milimeters, miles, yards, feet, inches, grades and pixels.

We can also specify if they are units “on the map” (the size would depend on where the zoom is set) or “on paper” (it will have a set size, both on screen and when it is printed).

• New: Access the properties of the symbols in order to make a new symbol.
• Save: Allows you to save the symbols you have created in gvSIG's library of symbols, with a .sym extension, in order to be able to use them as often as you need and also to configure different types of legends.
• Restart: Click on this button if you wan to restart the editing of a symbol.

You can chose between different Markers that are shown in “Type of Marker”.

Simple Marker:

In “Marker style”, select the marker (circle, square, cross...). You can modify its size, angle and colour as well as being able to move it around the ordinate and abscissa axis.

Marker made up of simple markers: you can make up a marker from various other simple markers by “overlapping” one over the other, this is done by clicking on “add layer”, where each layer is a simple marker. You can delete or change the order of the layers by clicking on “Delete layer” or “Tidy layers”. In the following image there is an example of a symbol made up of various simple markers.

You can make the symbols stand out by choosing the colour of the outline and giving it the same transparency as the fill-in of the symbols. To give the symbol an outline you must check the “Use outline” box. You can move the symbol around the ordinate and abscissa axis or leave it in the centre.

Character marker:

You can use the different alphanumeric character types to create a symbol, you can modify its size, angle and colour as well as being able to move it around the ordinate and abscissa axis.

Picture marker:

You can chose whichever image you want to represent the symbol. This image can be in different formats (jpg, png,bmp, svg..., you can even download an image from the internet, as long as the format is supported by gvSIG). To add it just select the path where the image is saved by clicking on “Examine”, next to "Image file".

Also, you have the option of selecting a different image, which is to represent the geometries, when they have been selected and are in view. Do this by entering the path of the image in "Selected image".

You can move the symbol around the ordinate and abscissa axis or leave it in the centre.

You can choose between different Mercator that are shown in the “Mercator type”.

Simple line symbol:

You can choose the colour of the line, its breadth and its movement (offset), as well as having the option to modify its opaqueness and, of course, its measurement units.

As well as that the layers of the points can make up one line with various lines “overlapping” using the same method than which in the layers of points.

In the “Line properties” tab you can generate different types of lines, continuous lines which gvSIG has as default, or discontinuous lines, establishing the fill-in pattern you choose. For this a rule is made available from which you can design your own patterns.

• Fill-in pattern:

Click on the grey section which is on the rule and drag right, next click on the rule, in the rule section you want, and a black section will appear which you can eliminate if you “click” on it again. This way you can successively add sections which can design your line.

If you want to delete the designed line click on “clean”.

• Boarder style: You can chose between round, rectangular or none for the boarder style.
• Style of the union: You can chose between square, angles and rounded for the union of the lines.

In the “Arrow decorations” tab you can turn a line into an arrow. To make this happen check the “Use decoration” box.

The options available to decorate the arrow are:

• The size of the arrow.
• The sharpness of the arrow.
• Nº of positions: Number of times you want the “point” of the arrow to be repeated along the line.
• Choose Symbol: This button will take you the simple Mercator of a layer of points menu, here you can select the shape of the arrow “point” and configure it as if it were any other symbol.
• Reverse: You have the option of reversing the first or all the arrows from the line.
• Rotation: You can chose between the “point” of the arrow rotates according to the slope of the line or that it has a permanent inclination according to the page.

Mercator line symbols:

You can use different font types, such as characters, to create a symbol, modifying its breadth and separation.

Image line symbol:

You can chose the image you want to make up the line, this image can be in different formats (jpg, png, bmp, svg...). To add the image you only have to select the path to where the image is saved by clicking on “Examine”. You can set the breadth and scale the image in “X” and “Y”.

The following fill-in Types for polygonal geometry layers are available.

Simple fill-in:

You can choose the polygon fill-in colour and its opaqueness.

Click on the button where you can see the outline and the simple symbol of a line properties menu will open. Here you can configure the outline of the polygon as if it were a line.

You can give the outline the breadth and opaqueness you want.

Fill-in made up of simple mercators: You can make up a fill-in from various simples by “overlapping” them, it is the same method as that which is explained in the layers of points and lines.

Mercator fill-ins:

You can give the polygon a fill-in made up of different types of mercators, such as punctual, linear, image... with their own characteristics.

The fill-in can be organised in an aleatory way or in a regular mesh way.

There is the option to make compositions with various layers.

Line fill-in:

Instead of filling the polygon in with specific mercators you can do so with lines, you can give them the same properties that you gave a line layer, including the outlines.

As in all sections, here you can also create a composition through different layers.

Image fill-in:

You can fill-in the polygon of images and set their inclinations by indicating the angle and you can also scale them.

The way to fill-in the polygon of images is by giving them the specific route to the image. These images can be framed, click on “Outline” and select the line you want.

Gradient fill-in:

The possibility of gradually filling-in is available, you can select different options to configure the gradual scale of the colour, these options are:

• Intervals: Nº of intervals you want the gradual changing of the colour to be structured by.
• Percentage: You can chose to set the percentage of gradual change between 0 and 100%.
• Style: Select the style that you want for the fill-in from the drop-down menu.
• Angle: Angle of the fill-in colour.
• Colour gradient: Select the colour scale you want.
• Outline: Give the ploygon an outline, the process of this is the same as if it were a line.

Symbol levels

As you can see in the following image, a symbol has two buttons that configure it, “Select Symbol” where you can define its properties, and “Symbology Levels” which allows us to establish the exact order the different layers has created the symbol.

It is important to establish an order when different geometries of the same layer intersect, as can be the case in the unique Value of legends for line layers, for example, where the order established could be of interest so that some symbols are above others.

“0” value corresponds to the symbol drawn at that bottom, “1” is drawn above that and so forth successively.

Labels that show in ToC

You can give whatever name you want to the different legend values, to see them in the Table of Contents.

In the previous image we saw a legend by a unique Symbol, but it is also possible to give each of the legend values a label name by Interval, unique Value, etc. (or modify it, from each of the text boxes), as well as being able to modify the order with which theses values appear in ToC (throught the up/down arrows):

Library of Symbols

Upon installing gvSIC a folder called 'Symbols' is created in the user directory, here you can save different types of symbols (punctual, linear, polygonal...). In other words, it works as a library of symbols. Also, gvSIG includes, by default, a set of symbols from each type of geometry, saving them in the above mentioned folder.

Once a symbol is created, from the “Symbology select” menu, click on “Save”.

A window will open, allowing you to save the symbols on a specific route, inside the “Symbols” folder.

Name the symbol and click on save. Make sure you have saved the symbol as a .sym file and that when you open another layer of the same type of geometry, the library of symbols which has been saved appears.