Thread: [PyOpenGL-Users] Problem with numpy arrays and OpenGL textures

SourceForge Headquarters 225 Broadway Suite 1600 San Diego, CA 92101 +1 (858) 422-6466

Hi everyone,

I'm doing a project using wxPython and pyopengl, and I seem to have a
problem rendering textures. This is code that worked before my hard
drive had a meltdown, but not since I re-installed everything.

I've determined the problem is in the OpenGL part of my program. I do
some calculations to generate a 2D numpy array that holds the image
data, and pylab.imshow() shows me the image as it is meant to be. I
used the same algorithm in Octave and MATLAB, and all are giving me
the right picture.

However, using pyOpenGL and the numpyhandler functions (http://cours-
info.iut-bm.univ-fcomte.fr/docs/python/OpenGL/
OpenGL.arrays.numpymodule.NumpyHandler-class.html) doesn't seem to
work. I get a garbled screen pocked with black pixels. I am including
my openGL code below. What am I doing wrong?

And yes, I did make the dtype of my array 'float32'.

-------code snippets------

import wx
from wx.glcanvas import GLCanvas

from OpenGL.GLU import *
from OpenGL.GL import *
from OpenGL.arrays.numpymodule import NumpyHandler

PC = 1
RI = 0

class myGLCanvas(GLCanvas):
       def __init__(self, parent):
               GLCanvas.__init__(self, parent,-1)
               wx.EVT_PAINT(self, self.OnPaint)
               self.init = 0
               self.mode = -1
               # making a texture for the range image
               self.texture = glGenTextures(1)
               # making a spot for the point cloud points
               self.cloud = None
               return

       def OnPaint(self,event):
               dc = wx.PaintDC(self)
               self.SetCurrent()
               if not self.init:
                       self.InitGL()
                       self.init = 1
               self.OnDraw()
               return

       def OnDraw(self):
               glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
               if self.mode == RI:
                       self.drawRange()
               elif self.mode == PC:
                       self.drawCloud()

       def InitGL(self):
               glClearColor(0.0, 0.0, 0.0, 0.0);
               glClearDepth(1.0)
               glEnable(GL_DEPTH_TEST)
               glDepthFunc(GL_LEQUAL)
               glClear(GL_COLOR_BUFFER_BIT)

               glPixelStorei(GL_UNPACK_ALIGNMENT, 1)
               glPixelStorei(GL_PACK_ALIGNMENT, 1)

               #NTSC colour scales...
               glPixelTransferf(GL_RED_SCALE, 0.299);
               glPixelTransferf(GL_GREEN_SCALE, 0.587);
               glPixelTransferf(GL_BLUE_SCALE, 0.114);

               glMatrixMode(GL_PROJECTION)
               glLoadIdentity()
               glOrtho(0.0,1.0,0,1.0,-1.0,1.0)
               glMatrixMode(GL_MODELVIEW)
               glLoadIdentity()

               return

       def rangeImage(self, image):

               glBindTexture(GL_TEXTURE_2D, self.texture)
               glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE )

               glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
                                               GL_LINEAR)
               glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
GL_LINEAR)
               glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)
               glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)

               # flatten it into a list so the OpenGL calls work
               n = NumpyHandler()
               fI = image.flatten()
               flatImage = n.dataPointer(n.contiguous(fI))

               print n.contiguous(fI)

               gluBuild2DMipmaps(GL_TEXTURE_2D, 1, image.shape[0]+1,
image.shape[1]+1,
                                                       GL_LUMINANCE,
GL_FLOAT, flatImage)
               self.mode = RI
               self.OnDraw()

       def drawRange(self):
               ''' Controls the actual drawing of the range image'''

               glMatrixMode(GL_MODELVIEW)
               glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)

               glColor3f(1.0,1.0,1.0)
               glEnable(GL_TEXTURE_2D)
               glBindTexture(GL_TEXTURE_2D, self.texture)
               glBegin(GL_TRIANGLE_FAN)
               glTexCoord2d(1,1); glVertex3f(0.0, 0.0, 0.0)
               glTexCoord2d(1,0); glVertex3f(0.0, 1.0, 0.0)
               glTexCoord2d(0,0); glVertex3f(1.0, 1.0, 0.0)
               glTexCoord2d(0,1); glVertex3f(1.0, 0.0, 0.0)
               glEnd()
               self.SwapBuffers()

--------end snippet-----------

Thread: [PyOpenGL-Users] Problem with numpy arrays and OpenGL textures

pyopengl-users