7705c34da4
also compare with doing the same thign via numpy and wx.BitmapFrombuffer. Flesh out the docstring. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@40922 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
196 lines
6.9 KiB
Python
196 lines
6.9 KiB
Python
import wx
|
|
|
|
# use the numpy code instead of the raw access code for comparison
|
|
USE_NUMPY = False
|
|
|
|
# time the execution of making a bitmap?
|
|
TIMEIT = False
|
|
|
|
# how big to make the bitmaps
|
|
DIM = 100
|
|
|
|
#----------------------------------------------------------------------
|
|
# attempt to import a numeric module if requested to
|
|
|
|
if USE_NUMPY:
|
|
try:
|
|
import numpy
|
|
def makeByteArray(shape):
|
|
return numpy.empty(shape, numpy.uint8)
|
|
numtype = 'numpy'
|
|
except ImportError:
|
|
try:
|
|
import numarray
|
|
def makeByteArray(shape):
|
|
arr = numarray.array(shape=shape, typecode='u1')
|
|
arr[:] = 0
|
|
return arr
|
|
numtype = 'numarray'
|
|
except ImportError:
|
|
USE_NUMPY = False
|
|
|
|
|
|
#----------------------------------------------------------------------
|
|
|
|
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)
|
|
|
|
if TIMEIT:
|
|
import timeit
|
|
timeit.s = self # Put self in timeit's global namespace as
|
|
# 's' so it can be found in the code
|
|
# snippets being tested.
|
|
if not USE_NUMPY:
|
|
t = timeit.Timer("bmp = s.MakeBitmap(10, 20, 30)")
|
|
else:
|
|
t = timeit.Timer("bmp = s.MakeBitmap2(10, 20, 30)")
|
|
log.write("Timing...\n")
|
|
num = 100
|
|
tm = t.timeit(num)
|
|
log.write("%d passes in %f seconds == %f seconds per pass " %
|
|
(num, tm, tm/num))
|
|
|
|
if not USE_NUMPY:
|
|
log.write("using raw access\n")
|
|
self.redBmp = self.MakeBitmap(178, 34, 34)
|
|
self.greenBmp = self.MakeBitmap( 35, 142, 35)
|
|
self.blueBmp = self.MakeBitmap( 0, 0, 139)
|
|
else:
|
|
log.write("using %s\n" % numtype)
|
|
self.redBmp = self.MakeBitmap2(178, 34, 34)
|
|
self.greenBmp = self.MakeBitmap2( 35, 142, 35)
|
|
self.blueBmp = self.MakeBitmap2( 0, 0, 139)
|
|
|
|
|
|
def OnPaint(self, evt):
|
|
dc = wx.PaintDC(self)
|
|
dc.DrawBitmap(self.redBmp, 50, 50, True)
|
|
dc.DrawBitmap(self.greenBmp, 110, 110, True)
|
|
dc.DrawBitmap(self.blueBmp, 170, 50, True)
|
|
|
|
|
|
def MakeBitmap(self, red, green, blue, alpha=128):
|
|
# Create the bitmap that we will stuff pixel values into using
|
|
# the raw bitmap access classes.
|
|
bmp = wx.EmptyBitmap(DIM, DIM, 32)
|
|
|
|
# Create an object that facilitates access to the bitmap's
|
|
# pixel buffer
|
|
pixelData = wx.AlphaPixelData(bmp)
|
|
if not pixelData:
|
|
raise RuntimeError("Failed to gain raw access to bitmap data.")
|
|
|
|
# We have two ways to access each pixel, first we'll use an
|
|
# iterator to set every pixel to the colour and alpha values
|
|
# passed in.
|
|
for pixel in pixelData:
|
|
pixel.Set(red, green, blue, alpha)
|
|
|
|
# This block of code is another way to do the same as above,
|
|
# but with the accessor interface instead of the Python
|
|
# iterator. It is a bit faster than the above because it
|
|
# avoids the iterator/generator magic, but it is not nearly as
|
|
# 'clean' looking ;-)
|
|
#pixels = pixelData.GetPixels()
|
|
#for y in xrange(DIM):
|
|
# for x in xrange(DIM):
|
|
# pixels.Set(red, green, blue, alpha)
|
|
# pixels.nextPixel()
|
|
# pixels.MoveTo(pixelData, 0, y)
|
|
|
|
|
|
# Next we'll use the pixel accessor to set the border pixels
|
|
# to be fully opaque
|
|
pixels = pixelData.GetPixels()
|
|
for x in xrange(DIM):
|
|
pixels.MoveTo(pixelData, x, 0)
|
|
pixels.Set(red, green, blue, wx.ALPHA_OPAQUE)
|
|
pixels.MoveTo(pixelData, x, DIM-1)
|
|
pixels.Set(red, green, blue, wx.ALPHA_OPAQUE)
|
|
for y in xrange(DIM):
|
|
pixels.MoveTo(pixelData, 0, y)
|
|
pixels.Set(red, green, blue, wx.ALPHA_OPAQUE)
|
|
pixels.MoveTo(pixelData, DIM-1, y)
|
|
pixels.Set(red, green, blue, wx.ALPHA_OPAQUE)
|
|
|
|
return bmp
|
|
|
|
|
|
def MakeBitmap2(self, red, green, blue, alpha=128):
|
|
# Make an array of bytes that is DIM*DIM in size, with enough
|
|
# slots for each pixel to have a RGB and A value
|
|
arr = makeByteArray( (DIM,DIM, 4) )
|
|
|
|
# just some indexes to keep track of which byte is which
|
|
R, G, B, A = range(4)
|
|
|
|
# initialize all pixel values to the values passed in
|
|
arr[:,:,R] = red
|
|
arr[:,:,G] = green
|
|
arr[:,:,B] = blue
|
|
arr[:,:,A] = alpha
|
|
|
|
# Set the alpha for the border pixels to be fully opaque
|
|
arr[0, 0:DIM, A] = wx.ALPHA_OPAQUE # first row
|
|
arr[DIM-1, 0:DIM, A] = wx.ALPHA_OPAQUE # last row
|
|
arr[0:DIM, 0, A] = wx.ALPHA_OPAQUE # first col
|
|
arr[0:DIM, DIM-1, A] = wx.ALPHA_OPAQUE # last col
|
|
|
|
# finally, use the array to create a bitmap
|
|
bmp = wx.BitmapFromBufferRGBA(DIM, DIM, arr)
|
|
return bmp
|
|
|
|
|
|
|
|
#----------------------------------------------------------------------
|
|
|
|
def runTest(frame, nb, log):
|
|
win = TestPanel(nb, log)
|
|
return win
|
|
|
|
#----------------------------------------------------------------------
|
|
|
|
|
|
|
|
overview = """<html><body>
|
|
<h2><center>Raw Bitmap Access</center></h2>
|
|
|
|
wx.NativePixelData and wx.AlphaPixelData provide a cross-platform way
|
|
to access the platform-specific pixel buffer within a wx.Bitmap. They
|
|
provide both a random access method, and an iterator interface.
|
|
|
|
<p>Unfortunately, although these classes are convienient ways to access
|
|
and update the contents of a wx.Bitmap, we lose most of the efficiency
|
|
of the C++ classes by requiring one or more Python-to-C++ transitions
|
|
for each pixel. In fact it can be <b>much</b> slower than the other
|
|
ways of creating a bitmap from scratch, especially now that
|
|
wx.BitmapFromBuffer exists and can save the time needed to copy from a
|
|
wx.Image.
|
|
|
|
<p>To see this difference for yourself this module has been
|
|
instrumented to allow you to experiment with using either the raw
|
|
access or numpy/numarray, and also to time how long it takes to create
|
|
100 bitmaps like you see on the screen. Simply edit this module in
|
|
the \"Demo Code\" tab and set TIMEIT to True and then watch
|
|
the log window when the sample is reloaded. To try numpy or numarray
|
|
(if you have them installed) then set USE_NUMPY to True as well, and
|
|
watch the log window again. On my machines there is about <b>an
|
|
order of magnitude</b> difference between the raw access functions
|
|
and using a numarray.array with wx.BitmapFromBufferRGBA! Almost
|
|
another order of magnitude improvement can be gained with using the
|
|
new numpy module!
|
|
|
|
</body></html>
|
|
"""
|
|
|
|
|
|
|
|
if __name__ == '__main__':
|
|
import sys,os
|
|
import run
|
|
run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])
|
|
|