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Home ChartPack RChart Class TRChart Methods Line
See also: MoveTo, DrawTo, LineWidth, Ellipse, Rectangle, Arrow, ActiveLayer, LineOffset, Arc, CursorVert, CursorHoriz, DoubleArrow, Cross 

Line


Unit: SDL_rchart
Class: TRChart
Declaration: [1] procedure Line (x1,y1, x2,y2: double);
[2] procedure Line (x1,y1, x2,y2: integer);
[3] procedure Line (x1,y1: integer; x2,y2: double);
[4] procedure Line (x1,y1: double; x2,y2: integer);

The method Line draws a line from the point (x1,y1) to the point (x2,y2). The drawing cursor is set to the position (x2,y2). The line can be drawn in different coordinate system modes: version [1] uses the world coordinates (these are the coordinates shown at the axes of the chart), version [2] uses the screen coordinates in pixels, and versions [3] and [4] mix them. Using screen coordinates (which are declared as integer) has the effect that the line segment remains at a fixed position even if the chart is panned or zoomed. Using mixed mode coordinates ([3] and [4]) allows to implement a "stretching" effect, with one end of the line staying in place and the other moving with the world coordinate system.

The line width may be adjusted by the property LineWidth. The color of the voids in dashed lines is controlled by the property FillColor.

Hint: In the Light Edition the number of chart elements is restricted to 1000 elements.

Example: This method is used in the following example programs (see http://www.lohninger.com/examples.html for downloading the code): cluster, interpol3d, multilinreg, processc, simplepca


Last Update: 2023-Dec-13