The wxPython tutorial

The Graphics Device Interfacehttp://www.zetcode.com/wxpython/gdi/angle = 0while (angle < 2*pi):x = radius*cos(angle)y = radius*sin(angle)dc.DrawLinePoint((0, 0), (x, y))angle = angle + 2*pi/360app = wx.App()Lines(None, -1, 'Lines')app.MainLoop()In this example we draw 260 lines from the middle of theclient area. The distance between two lines is 1 degree. Wecreate an interesting figure.import wxfrom math import hypot, sin, cos, piWe need three mathematical functions and one constant fromthe math module.dc.SetDeviceOrigin(size_x/2, size_y/2)The method SetDeviceOrigin() creates a new beginning of thecoordinate system. We place it into the middle of the clientarea. By repositioning the coordinate system, we make ourdrawing less complicated.radius = hypot(size_x/2, size_y/2)Here we get the Hypotenuse. It is the longest line, we candraw from the middle of the client area. It is the length of theline, that should be drawn from the beginning into the cornerof the window. This way most of the lines are not drawn fully.The overlapping parts are not visible. see Hypotenuse.x = radius*cos(angle)y = radius*sin(angle)These are parametric functions. They are used to find [x, y]points on the curve. All 360 lines are drawn from thebeginning of the coordinate system up to the points on thecircle.26 de 44 27/04/2008 1:08