# Module Scientific.TkWidgets.TkVisualizationCanvas

## Class PolyLine3D: Multiple connected lines

Constructor: PolyLine(points, **|attr|), where points is any sequence of (x, y, z) number triples and attr stands for line attributes specified by keyword arguments, which are `width` (an integer) and `color` (a string whose value is one of the color names defined in Tk). The default is a black line of width 1.

## Class VisualizationGraphics: Compound graphics object

Constructor: VisualizationGraphics(objects), where objects is a list whose elements can be instances of the classes PolyLine3D and VisualizationGraphics.

## Class VisualizationCanvas: Tk visualization widget

Constructor: VisualizationCanvas(master, width, height, **|attributes|). The arguments have the same meaning as for a standard Tk canvas. The default background color is white and the default font is Helvetica at 10 points.

VisualizationCanvas objects support all operations of Tk widgets.

Interactive manipulation of the display is possible with click-and-drag operations. The left mouse button rotates the objects, the middle button translates it, and the right button scales it up or down.

Methods:

- draw(graphics)

  Draws the graphics object graphics, which can be a PolyLine3D or a VisualizationGraphics object.

- clear(keepscale=`0`)

  Clears the canvas.