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# Rotation of figurec

## Pannel for setting orientation of figure

After 3D-plot is appeared a user may push the Rot button to precise some parameters of the figure orientation (fig.5.1).

Figure 5.1 Pannel for setting orientation of figure To illustrate the effects of these parameters some artificial surface with added several peaks to the previous function (Z= sin(x) * cos(y) ) is used on this page.

### Turn back (No, Yes)

Defines whether the figure has an ordinary orientation in the space or it is turned back to be looked from behind (fig.5.2). This option is used if some details of the surface are not visible in the ordinary orientation.

Figure 5.2 Strright and back images ### Exchanges X,Y - axes (No, Yes)

Exchanges X,Y - axes (No, Yes) Defines whether the X and Y axes have an ordinary (right hand) disposition in the coordinate system or inverse (left hand).

Figure 5.3 Exchanging X,Y - axes ### Inverse X (No, Yes)

(if Yes) causes the inversion of rows of the matrix i.e. data[i,j] = data [kpX-i, j]

Figure 5.4 Inversion along X - axis ### Inverse Y (No, Yes)

(if Yes) causes the inversion of rows of the matrix i.e. data[i,j] = data [i, kpY-j]

Figure 5.5 Inversion along Y - axis ### Mode of rotation over Y-axis

Defines whether the horizontal axis for rotation is the horizontal line of the screen or the horizontal edge of the painted object.

Figure 5.6 Different modes of rotation ### Choose axis to set angle

Shows the orientation of the object in the space. The latter is defined by the two angles. The first is the one around vertical axis (has the limits 0-90 grades). The second is the one around horizontal axis (has the same limits). A correction of these angles by a user may be set either immediately by entering the new values into the command text string (see fig. 5.6) or by adding the some number from the downer choose panel .In order to rotate figure more than 90 grades an option "Turn back" should be used.

## Rotation of figure by mouse

A user may rotate figure by middle mouse button. To do this he should press the middle mouse button and move cursor in the screen to achieve a desirable orientation of figure in the space. When the middle button is pressed the edges of box , currently containing a surface, are appeared. A horizontal displacement of the cursor causes the corresponding changing of the angle of rotation around Z-axis in the Rot window, while the vertical displacement of the cursor causes the changing of the angle of rotation around X-axis (fig. 5.7 left). The current plot of the box is simultaneously changing. It is most convenient to hold a cursor close to the nearest angle of the box. One may release the middle button move the cursor in other position and repeat rotation. After satisfying orientation is achieved one should click the 3d button (or right mouse button) to create a whole image (fig. 5.7 right).

Figure 5.7 Rotation of figure by middle mouse button 