The great wxVScrolledWindow refactoring: allow using it both horizontal and

[wxWidgets.git] / wxPython / demo / GraphicsContext.py

import wx
import colorsys
from math import cos, sin, radians

#----------------------------------------------------------------------

BASE  = 80.0    # sizes used in shapes drawn below
BASE2 = BASE/2
BASE4 = BASE/4


class TestPanel(wx.Panel):
    def __init__(self, parent, log):
        self.log = log
        wx.Panel.__init__(self, parent, -1)

        self.Bind(wx.EVT_PAINT, self.OnPaint)

    def OnPaint(self, evt):
        dc = wx.PaintDC(self)
        try:
            gc = wx.GraphicsContext.Create(dc)
        except NotImplementedError:
            dc.DrawText("This build of wxPython does not support the wx.GraphicsContext "
                        "family of classes.",
                        25, 25)
            return

        font = wx.SystemSettings.GetFont(wx.SYS_DEFAULT_GUI_FONT)
        font.SetWeight(wx.BOLD)
        gc.SetFont(font)

        # make a path that contains a circle and some lines, centered at 0,0
        path = gc.CreatePath()
        path.AddCircle(0, 0, BASE2)
        path.MoveToPoint(0, -BASE2)
        path.AddLineToPoint(0, BASE2)
        path.MoveToPoint(-BASE2, 0)
        path.AddLineToPoint(BASE2, 0)
        path.CloseSubpath()
        path.AddRectangle(-BASE4, -BASE4/2, BASE2, BASE4)


        # Now use that path to demonstrate various capbilites of the grpahics context
        gc.PushState()             # save current translation/scale/other state 
        gc.Translate(60, 75)       # reposition the context origin

        gc.SetPen(wx.Pen("navy", 1))
        gc.SetBrush(wx.Brush("pink"))

        # show the difference between stroking, filling and drawing
        for label, PathFunc in [("StrokePath", gc.StrokePath),
                                ("FillPath",   gc.FillPath),
                                ("DrawPath",   gc.DrawPath)]:
            if "wxGTK" in wx.PlatformInfo:
                w, h = dc.GetTextExtent(label) # NYI in Cairo context
            else:
                w, h = gc.GetTextExtent(label)

            gc.DrawText(label, -w/2, -BASE2-h)
            PathFunc(path)
            gc.Translate(2*BASE, 0)

            
        gc.PopState()              # restore saved state
        gc.PushState()             # save it again
        gc.Translate(60, 200)      # offset to the lower part of the window
        
        gc.DrawText("Scale", 0, -BASE2)
        gc.Translate(0, 20)

        # for testing clipping
        #gc.Clip(0, 0, 100, 100)
        #rgn = wx.RegionFromPoints([ (0,0), (75,0), (75,25,), (100, 25),
        #                            (100,100), (0,100), (0,0)  ])
        #gc.ClipRegion(rgn)
        #gc.ResetClip()
        
        gc.SetBrush(wx.Brush(wx.Colour(178,  34,  34, 128)))   # 128 == half transparent
        for cnt in range(8):
            gc.Scale(1.08, 1.08)    # increase scale by 8%
            gc.Translate(5,5)     
            gc.DrawPath(path)


        gc.PopState()              # restore saved state
        gc.PushState()             # save it again
        gc.Translate(400, 200)
        gc.DrawText("Rotate", 0, -BASE2)
        
        gc.Translate(0, 75)
        for angle in range(0, 360, 30):
            gc.PushState()         # save this new current state so we can pop back to 
                                   # it at the end of the loop
            r, g, b = [int(c * 255) for c in colorsys.hsv_to_rgb(float(angle)/360, 1, 1)]
            gc.SetBrush(wx.Brush(wx.Colour(r, g, b, 64)))

            # use translate to artfully reposition each drawn path
            gc.Translate(1.5 * BASE2 * cos(radians(angle)),
                         1.5 * BASE2 * sin(radians(angle)))

            # use Rotate to rotate the path
            gc.Rotate(radians(angle))

            # now draw it
            gc.DrawPath(path)
            gc.PopState()

        gc.PopState()
        

#----------------------------------------------------------------------

def runTest(frame, nb, log):
    win = TestPanel(nb, log)
    return win

#----------------------------------------------------------------------



overview = """<html><body>
<h2><center>wx.GraphicsContext and wx.GraphicsPath</center></h2>

The new advanced 2D drawing API is implemented via the
wx.GraphicsContext and wx.GraphicsPath classes.  They wrap GDI+ on
Windows, Cairo on wxGTK and CoreGraphics on OS X.  They allow
path-based drawing with alpha-blending and anti-aliasing, and use a
floating point cooridnate system.

<p>When viewing this sample pay attention to how the rounded edges are
smoothed with anti-aliased drawing, and how the shapes on the lower
half of the window are partially transparent, allowing you to see what
was drawn before.

</body></html>
"""



if __name__ == '__main__':
    import sys,os
    import run
    run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])