import wx import array #---------------------------------------------------------------------- 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) self.width, self.height = 120,120 self.MakeBitmapRGB(self.width, self.height) self.MakeBitmapRGBA(self.width, self.height) self.MakeBitmapRGBpA(self.width, self.height) def GetRGB(self, x, y, bpp): # calculate some colour values for this sample based on x,y position r = g = b = 0 if y < self.height/3: r = 255 if y >= self.height/3 and y <= 2*self.height/3: g = 255 if y > 2*self.height/3: b = 255 if bpp == 4: a = int(x * 255.0 / self.width) return r, g, b, a else: return r, g, b def MakeBitmapRGB(self, width, height): # Make a bitmap using an array of RGB bytes bpp = 3 # bytes per pixel bytes = array.array('B', [0] * width*height*bpp) for y in xrange(height): for x in xrange(width): offset = y*width*bpp + x*bpp r,g,b = self.GetRGB(x, y, bpp) bytes[offset + 0] = r bytes[offset + 1] = g bytes[offset + 2] = b self.rgbBmp = wx.BitmapFromBuffer(width, height, bytes) def MakeBitmapRGBA(self, width, height): # Make a bitmap using an array of RGBA bytes bpp = 4 # bytes per pixel bytes = array.array('B', [0] * width*height*bpp) for y in xrange(height): for x in xrange(width): offset = y*width*bpp + x*bpp r,g,b,a = self.GetRGB(x, y, bpp) bytes[offset + 0] = r bytes[offset + 1] = g bytes[offset + 2] = b bytes[offset + 3] = a self.rgbaBmp = wx.BitmapFromBufferRGBA(width, height, bytes) def MakeBitmapRGBpA(self, width, height): # Make a bitmap using an array of RGB bytes plus a separate # buffer for the alpha channel bpp = 3 # bytes per pixel bytes = array.array('B', [0] * width*height*bpp) for y in xrange(height): for x in xrange(width): offset = y*width*bpp + x*bpp r,g,b = self.GetRGB(x, y, bpp) bytes[offset + 0] = r bytes[offset + 1] = g bytes[offset + 2] = b # just use an alpha buffer with a constant alpha value for all # pixels for this example, it could just as easily have # varying alpha values like the other sample. alpha = array.array('B', [128]*width*height) self.rgbaBmp2 = wx.BitmapFromBuffer(width, height, bytes, alpha) def DrawBitmapAndMessage(self, dc, bmp, msg, x_, y_): x, y = x_, y_ # draw some text to help show the alpha dc.SetFont(self.GetFont()) while y < y_ + self.height + 2*dc.GetCharHeight(): dc.DrawText(msg, x,y) y += dc.GetCharHeight() + 5 # draw the bitmap over the text dc.DrawBitmap(bmp, x+15,y_+15, True) def OnPaint(self, evt): dc = wx.PaintDC(self) self.DrawBitmapAndMessage(dc, self.rgbBmp, "No alpha channel in this image", 30,35) self.DrawBitmapAndMessage(dc, self.rgbaBmp, "This image has some alpha", 325,35) self.DrawBitmapAndMessage(dc, self.rgbaBmp2,"This one made with RGB+A", 180,220) #---------------------------------------------------------------------- def runTest(frame, nb, log): win = TestPanel(nb, log) return win #---------------------------------------------------------------------- overview = """

## BitmapFromBuffer

Two new wx.Bitmap factory functions allow you to create a wx.Bitmap directly from a data buffer. The the buffer can be any Python object that implements the buffer interface, or is convertable to a buffer, such as a string or an array. The new functions are:
• wx.BitmapFromBuffer(width, height, dataBuffer, alphaBuffer=None): Creates the bitmap from a buffer of RGB bytes, optionally with a separate buffer of alpha bytes.
• wx.BitmapFromBufferRGBA(width, height, dataBuffer): Creates the bitmap from a buffer containing RGBA bytes.
""" if __name__ == '__main__': import sys,os import run run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])