Info:
Select this check box if you want to see the pixel values when you press the left mouse button in a map window. Clear this check box if you do not want to see pixel values.
Scale limits:
Select this check box when this map should be displayed or hidden depending on the scale specified in the scale control of the map window; specify the scale range within which the map should be displayed. The map will be automatically hidden if the scale of the map window is outside this range.
With this option you can achieve for instance, that very detailed maps (e.g. on cadastral units) are only displayed when using a large scale in a map window, or that very general maps which depict overviews are only displayed when using a small scales in a map window, etc.
Clear this check box when you wish to display the map regardless of the scale of the map window.
Transparent:
Select this check box when you wish to display this raster layer with a certain transparency. Any layer that has been added to the map window before, e.g. an image or a shadow map, will remain partly visible through the transparent raster layer. Subsequently, type a value for the transparency rate (percentage): value 1 means almost not transparent, and value 99 means almost totally transparent.
Clear this check box to just display the layer, i.e. non-transparent.
Mind:
- For Transparency, the Display Settings of your screen must be set to 32 bit (True Color).
- When the map window already displays another raster map, you can only add raster maps which have the same georeference. You can use the Resample operation to transform a raster map to a desired georeference.
Text:
Select this check box if you want to see pixel values displayed as text on top of the pixels. Subsequently, select a color for the text from the appearing Text Color list box. Clear this check box if you just want to see the map.
Representation:
Select a representation with which the map should be displayed; open the list box by clicking it. You can select one of the system representations, a user-defined representation value linked to the domain of this map, or a user-defined representation gradual. Or create a new representation value by clicking the little create button. By creating a new representation value with the Representation Value/Gradual editor, you can make the values of the map appear as if they were 'classified'; but the original values are retained.
Stretch:
In case you selected a user-defined representation value, the map is displayed in the colors as defined in that representation.
In case you selected a representation gradual, the map will be stretched and the user has to indicate the stretch range:
- For value maps that are stored using 1 or 2 bytes per pixel value, the histogram of the map is automatically calculated when the map itself is calculated. In that case the 1% interval values of the histogram are given as the default stretch range.
- For value maps that are stored using 4 or 8 bytes per pixel value, only the minimum and maximum values in the map are calculated when the map is calculated. Then, these minimum and maximum values are given as the default stretch range. When you want to stretch on the 1% interval, you have to calculate a histogram yourself with the Histogram operation.
- When neither a histogram nor minimum and maximum values are available, the minimum and maximum values of the domain are given as the default stretch range.
Linear:
Choose Linear stretching to stretch the values of the map between the minimum and maximum value of the Stretch range linearly and map the result on the colors of the representation gradual.
Logarithmic:
Choose Logarithmic stretching to stretch the values of the map between the minimum and maximum value of the Stretch range logarithmically and map the result on the colors of the representation gradual.
Light, etc.:
Select option Light to display this map a little lighter than normal, select option Normal to display this map with normal brightness, or select option Dark to display this map a little darker than normal. Select option Gray to display this map in gray tones regardless of the selected representation.
Create Pyramid Layers:
In case pyramid layers are not yet available for this raster map:
- Select this check box to create pyramid layers for this raster map. Pyramid layers speed up the display of large raster maps in a map window.
- Clear this check box if you do not wish to create pyramid layers for this raster map.
For more information on pyramid layers, see ILWIS objects : Raster maps - Pyramid layers.