Supplementary modes of creation

The supplementary object creation modes are used to provide spatial topological relationships between objects that can belong to one or different map layers. Using supplementary object creation modes you can copy existing point or object portion to creating object with or without node creation. To activate supplementary object creation mode use corresponding option of pop-up menu ( which appear after using right button click ) or appropriate keyboard key.

As further there is a concept of a PSEUDO-POINT repeatedly in the text , so it  is represented logical to explain sense of this concept.

There is a part of the object limited by points 1 and 2. These points are real, they really exist in the object metric.  At execution of some editings (for example, editing an isolated object point) the auxiliary  permanently connecting crossing of the cursor with some object point dotted line displays, what point of the edited object is nearer to the cursor in the present situation , i.e. what point will be edited at left button click. Thus the dotted line "runs" only on real points. However in other modes   (for example, the creation of a point on the present object) crossing is bridged to the edited object on a shortest distance irrespective of, whether there is on the object in this place a real point whether or not. Thus, the pseudo-point is a really nonexistent point lying on a segment, connecting two adjacent real point. In other words pseudo-point is a tangency point of the directly edited object and a line which connects crossing to the edited object.

Supplementary object creation modes include:

L-  to close the created line object;

Back - to delete the last created point;

Space (blank) - transition to creation of a next subobject;

Insert - Insert of a point by coordinates or distance and direction;

I - copying of a real point;

T - referencing to a line;

P - copying of an object fragment;

D - change digitizing direction;

H - creation of a horizontal line;

V - creation of a vertical line;

R  - right angle;

F - cancellation of modes H, V and R;

C - current raster selection (at vectorization  (tracing));

M - to memorize a cursor position on a map;

N  - to return to the last (saved by M) point;

X  - to return to the previous (saved by M) point;

O - start of automatic watching (vectorization);

Copying of a real point ( I )

This mode is useful if you want to create object that exactly goes through an existent point of already created object or through the dot object. For example you "draw" an electric power line connecting existing piers (point objects).  To do it  you can plot dot objects (piers) at the beginning, and then having taken advantage the described mode to conduct a line of electrotransmissions passing through these support by series copying of their coordinates.

To activate Copying of a real point mode, press I key or select corresponding menu item, used for snapping to, and start drawing. After that it is necessary to select the object - source and to point at it a patterned point (in case of lines and polygons object - source).

Referencing to a line (T).

This mode is similar to previous one, but now you use as patterned the pseudo- point  (calculated, really nonexistent point arranged on a line, connecting two next  real point) . During copying the answer point ( i.e. point having coordinates of a    selected pseudo-point) is created on the object - source.

Change digitizing direction (D).

The mode is intended for a сhange digitizing direction of the object during its creation.

Copying of an object fragment (P).

This mode is useful if created and existing objects should have common part (fragment). Fragment selection is making by 3 points - (start, middle, end of fragment). Second point can be equal to the first or third one.In that case choice of a segment is made by two points. However for the closed object in order to prevent ambiguous identification of the selected fragment it is necessary to produce choice only by three points!

Creation of a horizontal line (H).

At activation of the given mode the construction of a current fragment of the created object will be produced strictly in a horizontal direction.

Creation of a vertical line (V).

At activation of the given mode the construction of a current fragment of the reated object  will be produced strictly in a vertical direction.

Creation of a right angle (R).

At activation of the given mode the construction of a current site of the created object will be produced perpendicularly previous.

Cancellation of modes H,V and R (F).

Cancels modes H,V and R.

Current raster selection (at vectorization  (tracing)) (C).

During vectorization (tracing), it is possible to create an object over several opened rasters.

To memorize a cursor position on a map (M).

Use this mode to go to map point "marked" by cursor. You can "remember" up to 20 cursor position.The subsequent return will be realized to the last saved point.

To return to last (saved by mode M) point (N).

To go to last "memorized" cursor position (see M mode).

To return to previous (saved by mode M) point (X).

To go to previous "memorized" cursor position (see M mode)

Start of autom atic watching (vectorization) (O).

Starts the process of a vectorization.

Transition to creation of a next subobject (Space (blank)).

At creation of the linear object there is a possibility of the composite object (object + subobjects) creation. The transition to creation of a next subobject is carried out pressing the key "Blank".

Insert of a point by coordinates or distance and direction (Insert ).

If necessary next point of the created linear or polygon object can be entered by the direct setting of its coordinates or direction (directional or right rotary corner) and distance from the previous point.