Raster Selections
Brief
description: to perform operations
such as editing an object’s geometry and modifying an object’s properties
with the Inspector, you first need to select the data to apply the commands
to. In this section we consider raster data selection technology
(raster images and their fragments; raster objects). You will learn about
different selection modes and methods of data selection, and tuning raster
selection.
WiseImage
allows the selection of raster data. Selection technology and data selection
methods are extremely close to vector object selection technology.
WiseImage
allows selection of the following raster data:
- Raster objects
(raster lines, arcs, circles, selected with object selection methods,
which come with “grips”, properties and precise geometry).
- Area fragments
of the raster image.
- Selected with a window
or polygon.
- Raster line segments
of arbitrary shape. (A segment represents a raster line of arbitrary
shape, limited by points of intersection with other raster lines
or endpoints).
- Isolated raster fragments
There are two toolbars for
data selection: Raster Select and More Selection.
IMPORTANT: When selecting data, you need
to define three parameters:
- Selection modes
– add to selection, remove from selection, single selection.
- Selection method
– by picking, within window, crossing polygon and others.
Raster
Selection modes
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New
data is added to selection |
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Selected
data is removed from selection |
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Every
new selection deselects previously selected data |
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Selects
all raster image contents |
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Deselect
All |
Raster Selection
Methods
Object selection
methods
- You can select raster objects
(raster lines, arcs & circles) using object selection methods:
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By
Picking (Auto) |
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By
Crossing Window |
 |
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Within
Window |
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By
Crossing Polygon |
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Within
Polygon |
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By
Crossing Fence |
- You can also select raster
objects by reference objects:
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Raster line
or its segment by 2 points |
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Raster arc
or its fragment by 3 points |
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Raster circle
by two points |
How to obtain
area selection using object selection methods:
| IMPORTANT: If you need to obtain
an area selection when selecting raster objects press the Disable
Raster Object Production button, located on the Select
toolbar. |
 |
Selecting
area raster fragments
Selecting inside rectangle
or polygon
- You can select rectangular
or polygonal fragments of a raster image using Select by Rectangle
and Select by Polygon, located on the
Raster Select toolbar.
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Rectangular
fragment of raster image |
 |
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Polygonal
fragment of raster image |
Selecting
raster segments
A Segment
represents part of a raster line of arbitrary shape, limited by intersection
points with other raster lines or endpoints.
- You can select raster line
segments:
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Within window |
 |
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Within polygon |
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By crossing window |
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By crossing polygon |
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By crossing fence |
Selecting
isolated raster fragments
- You can select isolated
raster objects:
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By picking |
 |
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Within window |
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Within polygon |
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By crossing
window |
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By crossing
polygon |
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By crossing
fence |
Tuning raster
selection
You need to
tune the geometry of raster data to obtain the best results when selecting
raster objects and raster segments.
How
to tune raster selection:
The selection
geometry is tuned using the R2V Conversion Options
dialog.
To open this
dialog, choose Conversion Options from the rConvert
menu, and then go to the Options tab.
Specify
the following values in the Options tab:
Max.Width
– the maximum width of raster objects to select. The value of this parameter
should be slightly greater than the maximum width of raster objects or
raster line segments.
Max.
Break – the maximum length of ignored breaks in raster lines.
Accuracy – your document accuracy. For example, if when
selecting a raster circle by picking, the program only selects a fragment
(arc), reduce the accuracy value.
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