Cutting of the areas

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ic_0087 The given mode is intended for creation of the new polygon (square) objects which are being inside of the specified one. For example, at designing position of new sites within the selected area. It is necessary for user to choose dissected polygon, then to set a line along which a cutting will be done. The line is set by the indication of two any points on a map. If it is necessary to cut off the areas along any of the sides of initial object then at the specifying of a line it is necessary the cursor of the "mouse" manipulator to place as much as possible close to that side of polygon (range)}, perpendicularly to which one it is necessary to make cutting. After a choice of object on the screen a dialogue appears in which the area and number of new objects are specified. Probably two variants of formation. The first -number of new objects is specified, and the program counts their area. The second - the areas of new objects are specified, and the program counts their quantity. At formation by the second variant, the area of the last object is equal to a remainder of division of the area of dissected object on the area of new objects.      

 

Cutting initial polygon onto N new objects with the equal area.

In dialogue of a mode it is necessary to set:    

N - number of the areas;      

delta S - an error for cutting one area;      

delta L - a linear error at cutting one area.

 

Areas are cut by pieces, perpendicular to the line set by the user. The areas are cut one by one, by turns from right or from the left end of object. The left or right end is defined at random. The area of initial object is divided onto N, the area of new object S is got. On i-th step the cut off area has Si size. If the difference |Si-S|<delta S the steps of consecutive approximation are come to an end and the new area is considered Si. If |Si-S|> delta S the check of distance between secant lines Li and L (i-1) is carried out. If the distance between them is less delta L the steps of consecutive approximation of selection of the area are come to an end and the new area is considered Si. Thus, the new area can differ from a preset value onto a random value within the limits of preset as delta S and delta L. In order, that new area was approached maximumly close to calculated value it is necessary to reduce values of delta S and delta L. However in this case process of integration can proceed long enough, and at small values of delta S and delta L do not receive a convergence at all.  

Cutting initial polygon onto new objects by the specified area.

In dialogue it is necessary to set:      

S - the size of the cut-off areas;      

delta S - an error for cut-off the areas;      

delta L - a linear error at cutting.      

 

Program calculates quantity of the cut areas. For this purpose the area of the selected object is divided onto S and the number of new objects N is got. In the given method probably presence of a remainder of division of initial polygon onto the area of the specified size. This remainder on a first step of the program is cut off from one of the ends of the selected object, and then the remained part is divided onto N equal parts by algorithm of a section onto N new objects.