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 = """<html><body>
<h2><center>BitmapFromBuffer</center></h2>
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: <ul>
<li><b>wx.BitmapFromBuffer</b>(width, height, dataBuffer, alphaBuffer=None):
Creates the bitmap from a buffer of RGB bytes, optionally with a separate
buffer of alpha bytes.
<li><b>wx.BitmapFromBufferRGBA</b>(width, height, dataBuffer): Creates
the bitmap from a buffer containing RGBA bytes.
</ul>
</body></html>
"""
if __name__ == '__main__':
import sys,os
import run
run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])
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