[[110:orbitgis:datasets:legend:index|{{  orbitgis:datasets:legend:return_to_overview_legend.png|}}]]

====== Great Topics about Legend and Labeling =====

===== Page Index =====

  * [[#Spatial Component vs Attribute Component]]
  * [[#Classification vs Basic appearance]]
  * [[#Classification Direct link]]
  * [[#Manage your own symbol-libraries]]
  * [[#Legend vs Linked Table]]

===== Spatial Component vs Attribute Component =====

==== Legend vs modeltype ===

{{datastructure_basicclassification.png?nolink}}

Depending on the modeltype of the dataset, other parameters will appear:
  * Parameters of the Basic Appearance
  * Parameters used for a Classification

^   Vector Data   ^^^
^  Points  ^  Lines  ^  Areas  ^
|   -> Add Labels and Pie Charts!   |||
| - Represent point objects by Symbols \\ \\ \\ \\ \\ -> Use Classification! | - Add Colors, Width and Line Style to line objects \\ - Add a Symbol repetition to line objects \\ \\ \\ \\ -> Use Classification! | - Adjust the outline: Add Colors, Width and Line Style \\ - Adjust the outline: Add a Symbol repetition \\ - Adjust the fill area: Add fill Colors, Gradient, Texture or Hatchlines \\ \\ -> Use Classification! |
^   Image & Raster Data   ^^^
^  Images Standard  ^  Black and White Images  ^  Raster  ^
| - Use a transparent color \\ - Adjust the image colors: brightness, contrast, saturation \\ \\ \\ | - Use a transparent color \\ - Adjust the background and foreground color separately \\ \\ \\ | - Use a transparent color \\ - Add colors to missing samples and background samples \\ \\ \\ -> Use Classification! |

==== Display attribute values on the mapcanvas ===

{{datastructure_labelpiechart.png?nolink}}

The attributevalues can be visualised on the map canvas as Labels or represented in Pie Charts.

Important: Only **vector-formats** can contain an attribute component!

\\ \\
===== Classification vs Basic appearance =====

This is an example when more classifications are used. Depending of the content of the attribute the appearance of the object will change.

{{classba_olg.png?nolink}}

This is how the legend is build:

^   Basic Appearance   | {{classba_ba.png?nolink}} |
^   Classification I   | {{classba_cl1.png?nolink}} |
^   Classification II   | {{classba_cl2.png?nolink}} |
^   Classification III   | {{classba_cl3.png?nolink}} |
|   **Tips:** \\ - Add a class in the first classification that is the same as the Basic Appearance, with empty values. This way it is possible to create a \\ label for non-classified objects. For example choose 'Not Classified' as label. \\ - In the other classifications: remove the classes that are equal to the basic appearance (f.e. remove object: the class with value 'false' \\ and visibility 'true' is not part of the legend \\ - Only use parameters that are able to combine with eachother and not interact.   ||

^ Examples ^^^
| {{classba_ex1_oi.png?nolink}} |   {{classba_ex1_map.png?nolink100}}   | Not classified |
| {{classba_ex2_oi.png?nolink}} |   {{classba_ex2_map.png?nolink100}}   | Type B |
| {{classba_ex3_oi.png?nolink}} |   {{classba_ex3_map.png?nolink100}}   | Not classified \\ Low Importancy |
| {{classba_ex4_oi.png?nolink}} |   {{classba_ex4_map.png?nolink100}}   | Type A \\ High Importancy |
| {{classba_ex5_oi.png?nolink}} |   {{classba_ex5_map.png?nolink100}}   | Type C \\ Medium Importancy \\ Deleted Object |
|   **Classification vs Basic Appearance:** \\ - In the first example, everything is based on the basic appearance. \\ - In the second example the fill color is based on the classification, the outline on the basic appearance \\ - In the third example the outline is based on the classification, and the fill color on the basic appearance. \\ - In the fourth example outline and fill color are based on the classification. \\ - In the fifth example outline and fill color are based on the classification, but are overruled by the classification of the visibility.   |||

More information about Classifications, see [[110:orbitgis:datasets:legend:classification:index]]

\\ 
===== Classification Direct link =====

^ Example ^^
| {{orbitgis:datasets:legend:topics:classdi_ex_oi.png?nolink}} | {{orbitgis:datasets:legend:topics:classdi_ex_map.png?nolink}} |

All information see: [[110:orbitgis:datasets:legend:classification:direct|]]


===== Manage your own symbol-libraries =====

Use more symbols by adding your own symbol libraries to Orbit GIS!

{{symbollibrary.png?nolink}}

More information about Symbol Libraries, see [[110:orbitgis:datasets:legend:parameters:symbol_library]]

\\ \\
===== Legend vs Joined Table =====

In the legend, attribute values are used for classifications, labels and pie charts.
Those attributes are not always attributes from the dataset itself, but can also be derived from attributes of a linked table!
  * The attribute values are not stored in the dataset itself, but in an external table.
  * An easy way to add more information to a dataset.

==== shapefile ====

A Shapefile can only contain **one attribute set** and **one attribute value** for each attribute in the dataset itself. By joining an external table to the dataset, a new attribute set and value(s) are added to the dataset, however, it is not stored in the dataset itself!

^   Attribute values from the dataset   |   {{jointable_attr.png?nolink}}   |
^   Attribute values derived \\ from a Linked Table   | {{jointable_jt.png?nolink}} |
|   \\ -> this way it is possible to make a **Pie Chart by Classes** to shapefiles, by using the attribute values from the Linked Table!  \\ \\   ||

More information about Table join, see [[110:orbitgis:datasets:contents:join]]