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3.6. Draw menu

Draw Point

Purpose

Parameters

Remarks

Click once to place a point. Double-click to place the last point and exit the function.

Draw Line

Purpose

Parameters

Remarks

Click once to mark an end-point. Double-click to place the last end-point and exit the function.

Draw Region

Purpose

Parameters

Remarks

Click once to mark an end-point. Double-click to place the last end-point, close the polygon and exit the function.

Draw Box

Purpose

Parameters

Remarks

Click once to mark the first end-point. Double-click to place the last end-point and exit the function.

Draw Text

Purpose

Parameters

Remarks

The cursor marks the upper-left corner of the text. A box shows the size of the text. Click once to place the text and exit the function.

Draw Fill

Purpose

Parameters

Remarks

Click once to begin filling. The region around the selected point will be filled outward until the line color or the edge of the window is reached.

Draw Labels

Purpose

Parameters

Remarks

Draw Legend

Purpose

Draw a legend showing color table colors

Parameters

Color table
Text font
Text color
Coordinates (or use cursor)

Remarks

A legend shows the colors used to display an image or mapped data. The colors are stored in a color table file.

Legends are good for displaying colors either when the dataset contains few values or when only a few colors are assigned to ranges of values. If there are many colors in the color table, you may prefer to draw a colorbar with Draw Colorbar .

By default WinDisp3 automatically displays legends to the right of an image or map. Many users may wish to either display no legend at all, or to place the legend in a different position. The default legend function can be turned in Options Display.

The legend can be positioned manually with the cursor, or automatically by including coordinates in the Options Dialog Box. The specified region is filled top to bottom and left to right. If the specified region is not high enough to fit all legend items in one column, then the remainder of the items will be placed in successive columns. In the extreme, you may have only one item per column, or a horizontal legend.

White space can be left around the edges of an image to make room to place the legend with Options Define Window Size.

Draw Colorbar

Purpose

Draw a bar showing continuous colors from color table

Parameters

Color table
Text font
Text color
Minimum value (0-255)
Maximum value (0-255)
Coordinates (or use cursor)

Remarks

A colorbar is a useful way to show what colors are associated with which values in an image. The colorbar graphically depicts the range of image values over which a given color is used. If the image is classified, or contains discrete values, a legend may be more appropriate. Legends can be created with Draw Legend.

By default WinDisp3 automatically displays legends to the right of an image or map. Many users may wish to either display no legend at all, or to place the legend or colorbar in a different position. The default legend function can be turned in Options Display.

The colorbar can be positioned manually with the cursor, or automatically by including coordinates in the Options Dialog Box. The specified region is filled with the colorbar. If the width is greater than the height, the colorbar is drawn horizontally, otherwise it is drawn vertically. The colorbar size and position matches the coordinates given. Any text from the Key field in the color table is drawn below a horizontal colorbar or to the right of a vertical colorbar and is therefore outside of the specified coordinates.

If the text is associated with a range of colors, the text is placed at the center of that range. To place text at the beginning of a range, add a row to the color table before the row containing that range. The From and To values should be set to the first value of the range, and the Key should contain the text you want to print. For example:

From To Red Green Blue Key
0 0 0 255 255 First
0 81 0 255 255  
82 82 0 255 0 Second
82 254 0 255 0  
255 255 128 128 128 Water

White space can be left around the edges of an image to make room to place the colorbar with Options Define Window Size.

Draw Bitmap

Purpose

Display a bitmap at a specific location

Parameters

Bitmap name
Coordinates (or use cursor)

Remarks

A bitmap is displayed starting at the coordinates supplied, or where the cursor is clicked. When moving a cursor, a box shows the size and location of the bitmap to be displayed.


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This manual was prepared by the Global Information and Early Warning System of the United Nations Food and Agriculture Organization
© FAO/GIEWS - 1999
E-mail: Giews1@fao.org