[PyOpenGL-Users] I'm incapable of mapping a texture, in my small test.

[Alfonso C. <mis...@gm...>]

I exclude GLUT because it's malfunctioning, on my computer. I get the
following exception, when I import GLUT:

Traceback (most recent call last):
  File "C:\Documents and Settings\Alfonso\My
Documents\Python\PyOpenGL\PyOpenGL-
Demo-3.0.0a6\PyOpenGL-Demo\NeHe\lesson6.py", line 47, in <module>
    from OpenGL.GLUT import *
  File "build\bdist.win32\egg\OpenGL\GLUT\__init__.py", line 4, in <module>
  File "build\bdist.win32\egg\OpenGL\GLUT\special.py", line 73, in <module>
AttributeError: 'NoneType' object has no attribute 'glutDestroyWindow'

Since wxPython is operating well, I just left GLUT alone. In the test I
wrote, I rasterize the display, create a polygon the size of the
display-area, and *attempt* to render a mapped texture, on each cycle. I had
experienced no troble, coloring the rendered polygon. I've opened the
specified image, in a seperate program, and found that the image loads
properly. From my previous inquiries, I've come to believe that I've set up
OpenGL correctly. The texture ought to render. I do not understand what I am
doing wrongly.

from wx import *
from wx.glcanvas import GLCanvas

from OpenGL.GL  import *
from OpenGL.GLU import *

import Image, sys, math

SCREEN_WIDTH  = 400
SCREEN_HEIGHT = 400

def load_image(image_name):
    image = Image.open(image_name)

    width  = image.size[0]
    height = image.size[1]

    image_string = image.tostring('raw', 'RGBX', 0, -1)
    image_id     = glGenTextures(1)

    glBindTexture(GL_TEXTURE_2D, image_id)

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1)
    glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0,
                 GL_RGBA, GL_UNSIGNED_BYTE, image_string)

    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP)
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP)
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST)
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL)

    return image_id

class Canvas(GLCanvas):
    def __init__(self, parent, image_name):
        GLCanvas.__init__(self, parent, -1)
        EVT_PAINT(self, self.paint)
        self.texture_id = load_image(image_name)

    def paint(self, event):
        global SCREEN_WIDTH
        global SCREEN_HEIGHT

        dc = wx.PaintDC(self)
        self.SetCurrent()

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
        glLoadIdentity()

        glMatrixMode(GL_PROJECTION)
        glPushMatrix()
        glLoadIdentity()

        glOrtho(0, SCREEN_WIDTH, 0, SCREEN_HEIGHT, -1, 1)
        glScalef(1, -1, 1)
        glTranslatef(0, -SCREEN_HEIGHT, 0)

        glMatrixMode(GL_MODELVIEW)
        glPushMatrix()
        glLoadIdentity()

        glEnable(GL_TEXTURE_2D)

        self.draw()
        glMatrixMode(GL_PROJECTION)
        glPopMatrix()
        glMatrixMode(GL_MODELVIEW)
        glPopMatrix()

        self.SwapBuffers()
    #I kept draw() seperate to ease modifying the test-program.
    def draw(self):
        global SCREEN_WIDTH
        global SCREEN_HEIGHT

        glBindTexture(GL_TEXTURE_2D, self.texture_id)

        glBegin(GL_QUADS)

        glTexCoord2f(0, 0); glVertex2d(           0,             0)
        glTexCoord2f(1, 0); glVertex2d(SCREEN_WIDTH,             0)
        glTexCoord2f(1, 1); glVertex2d(SCREEN_WIDTH, SCREEN_HEIGHT)
        glTexCoord2f(0, 1); glVertex2d(           0, SCREEN_HEIGHT)

        glEnd()

def main():
    global SCREEN_WIDTH
    global SCREEN_HEIGHT
    app    = PySimpleApp()
    frame  = Frame(None, -1,
                   '2D Graphics',
                   DefaultPosition,
                   Size(SCREEN_WIDTH,SCREEN_HEIGHT))
    canvas = Canvas(frame, '128x128.bmp')
    #"128x128.bmp" is a place-holder.

    frame.Show()
    app.MainLoop()

if __name__ == '__main__': main()
-- 
...LOLz0rz.