Adobe Illustrator program offers various means for creation of vector images — from the most thin pen dashes before simulation of dabs of a paintbrush. At the same time specificity of vector graphics is rather far from drawing "manually". Therefore it is necessary to imagine how to create a vectorial circuit and as it to edit (to add and delete reference points, to change the form and etc.).
The circuit (path) is the line created by means of drawing инструменов of the program and representing a wire jacket of object. To a circuit can be then parameters обводки (stroke) and filling (fill) (fig. 5.1) are appropriated.
Normally the circuit consists of the several segments representing the elementary Bezier curves and connected in reference points (anchor points), or nodes. At relocation of one reference point the segments connected to it, change the form. To change the segment form it is possible also relocation of a controlling point (control point), connected to a reference point by means of a controlling line (control line).
The circuit is considered opened if initial and finite points are not shorted, and closed when initial and finite points merge in one point. At a closed circuit the meaning of the beginning and the end (though it not so for the program which contains language standards PostScript in the basis, unambiguously treating initial and an ending point in connection with necessity to define a direction for control of filling in composite circuits) is lost.
At filling of an open circuit the program leads the imaginary direct line connecting initial and finite points, and fills it as the closed circuit (fig. 5.2).
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| Rice 5.1. An example of a circuit of an ellipse with обводкой, filling and the selected reference point |
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| Rice 5.2. An example of filling of an open circuit |
To create circuits it is possible by means of the several tools allocated in a palette of tools. Advantage of vectorial circuits is possibility at any moment to change as an amount of reference points and accordingly an amount and the form of segments, and the size, the form, layout and filling of all object.
Tools groups Pencil (Pencil) (fig. 5.3) are intended for drawing of the arbitrary lines "manually" and removals of their fragments.
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| Rice 5.3. Group Pencil tools |
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| Rice 5.4. Dialog box Pencil Tool Preferences |
The main tool in group is tool Pencil (Pencil) which assignment consists in creation of idle lines. As a result of operation of this tool the vectorial circuit in which reference points are placed by the program automatically turns out, nevertheless. After termination of drawing by tool Pencil (Pencil) the received circuit, as well as any circuit, is accessible to editing.
The number of reference points depends on length and complexity of a drawable line, and also on setting of dialog box Pencil Tool Preferences (tool "Pencil" Parameters) (fig. 5.4) which is caused by double click on the tool button.
In the field Tolerances (Tolerance) two parameters, influencing character of a circuit (fig. 5.5) are presented.
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Value in the field Fidelity (Accuracy) defines distance in пикселах on which the cursor can deviate at drawing. Thus in a range from 0,5 to 20 пикселов tracking accuracy of driving of the cursor ("sensitivity of a pencil") is defined: the value, the more precisely a line is less and the will be reference points, and the above more, the the line will turn out "more smoothly". Value 2,5 is by default installed. Value can be installed and with the help бегунка adjustment bands. |
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Value in the field Smoothness (Smoothness) defines a circuit smoothness in a range from 0 to 100 %, thus the more value, the a circuit becomes more rounded. By default null value is accepted. |
Setting of flag Keep selected (to Leave selected) provides automatic selection of a circuit after its creation.
The drawn not closed line can be continued. For this purpose it is necessary to select it, then to bring the cursor to one of ending points and, pushing the mouse button, to lead a line further. This possibility becomes accessible if to install flag Edit selected paths (to Edit the selected circuits) and to define distance in a range from 2 to 20 пикселов.
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| Rice 5.5. The circuits created by means of tool Pencil, at different values of parameters Fidelity and Smoothness |
At drawing by this tool current values of a thickness and color обводки are used. Including the tool, it is necessary to bring the cursor to starting point, to push the mouse button and to start to draw, thus the path is marked by a pointwise line (fig. 5.6).
If it is required to short a circuit it is necessary to push a key [Alt] (white зершина a pencil, there where in a real pencil it is allocated sometimes ластик, becomes black color, and near to the cursor there will be a small circle), then to release the mouse button and only after that a key.
At the moment of circuit drawing, it can be connected to already available if at approach to its ending point to push a key [Ctrl].
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Nota Bene. It is necessary to pay attention to an interesting singularity of tool Pencil (Pencil): it is possible to change easily the form of the selected circuit if to draw near to it other circuit (fig. 5.7). Thus got precisely difficult to predict result the closed circuit, for example, can be broken off, the intermediate segments are lost. |
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| Rice 5.6. An example of creation of a circuit by means of tool Pencil |
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| Rice 5.7. An example of change of the form of a circuit by means of tool Pencil |
To change the circuit form, namely to soften it, (Smoothing) (
) groups Pencil (Pencil) is possible by means of special tool Smooth. Double click on the appropriate button of a palette of tools causes a dialog box identical to a window on fig. 5.4.
For operation of this tool it is necessary to select a circuit, and then to lead a line along all circuit or its segment. To repeat this operation follows before obtaining of demanded level of smoothness of a circuit (fig. 5.8).
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| Rice 5.8. An example of changes of the form of a circuit with помощый tool Smooth |
If the user works at present with tool Pencil (Pencil) or Paintbrush (Paintbrush) the key [Alt] switches them to tool Smooth (Smoothing).
To delete a circuit part, it is possible to use tool Erase (Ластик) (
) groups Pencil (Pencil). Action of this tool is not spread to the text and the objects created by means of tool Gradient Mesh (the Graded-index grid) (
).
Removal of fragments of the selected circuit results from carrying out by the tool (with the pushed left mouse button) along a demanded fragment (fig. 5.9).
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| Rice 5.9. An example of removal of a fragment of a circuit by means of tool Erase |