pyOpenGL check for bool

Question

This is my source code https://paste.fedoraproject.org/428184/89404314/

The error I got is this:

C:\Python27>python.exe wx_gl_vbo_001.py
Traceback (most recent call last):
  File "wx_gl_vbo_001.py", line 63, in <module>
    MyApp(redirect = False).MainLoop()
  File "C:\Python27\lib\site-packages\wx-3.0-msw\wx\_core.py", line 8628, in __init__
    self._BootstrapApp()
  File "C:\Python27\lib\site-packages\wx-3.0-msw\wx\_core.py", line 8196, in _BootstrapApp
    return _core_.PyApp__BootstrapApp(*args, **kwargs)
  File "wx_gl_vbo_001.py", line 60, in OnInit
    canvas = MyCanvas(frame)
  File "wx_gl_vbo_001.py", line 16, in __init__
    }""", GL_VERTEX_SHADER)
  File "C:\Python27\lib\site-packages\OpenGL\latebind.py", line 44, in __call__
    self._finalCall = self.finalise()
  File "C:\Python27\lib\site-packages\OpenGL\extensions.py", line 245, in finalise
    self.__name__,
OpenGL.error.NullFunctionError: Attempt to call an undefined alternate function (glCompileShader, glCompileShaderARB), check for bool(glCompileShader) before calling

dir(shaders) come with this functions:

 'compileProgram', 'compileShader', 'found', 'fragment_shader', 'geometry_shader4', 'get_program_binary', 'glAttachShader', 'glBindAttribLocation', 'glCompileShader', 'glCreateProgram', 'glCreateShader',

Haven't looked too deeply at your code, but you appear to call shaders.CompileShader instead of shaders.compileShader. Also, it looks like the shader you wrote actually is a version 120 shader, so try switching the shader version. Variables like gl_ModelViewProjectionMatrix do not exist anymore in modern versions of OpenGL as far as I know! — CodeSurgeon, Sep 16 '16 at 04:56
some problems come with PyPI and binary I got another error with: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling — Cătălin George Feștilă, Sep 16 '16 at 06:44

score 1 · Accepted Answer · answered Sep 20 '16 at 02:56

Sorry for getting back to you so late. Here is a demo that renders a triangle with opengl using the wxpython toolkit (which I have never tried before). In addition to what I noticed in the comments, I saw that you are not using the entire contents of your vbo array and that some of the things in your code such as "self.haveInited" were not necessary. Here is a sample that renders a vbo triangle using OpenGL 2.1.

import wx
from wx import glcanvas
import sys
from OpenGL.GL import *
from OpenGL.arrays import vbo
from OpenGL.GL import shaders
import numpy as np

class MyCanvas(glcanvas.GLCanvas):
    def __init__(self, parent):
        glcanvas.GLCanvas.__init__(self, parent, -1)
        self.context = glcanvas.GLContext(self)
        self.Bind(wx.EVT_PAINT, self.OnPaint)

    def OnPaint(self, event):
        dc = wx.PaintDC(self)
        self.SetCurrent(self.context)
        self.InitGL()
        self.OnDraw()

    def InitGL(self):
        glClearColor(0, 0, 0, 1)
        VERTEX_SHADER = shaders.compileShader("""
        #version 120
        void main() 
        {
            gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
        }
        """, GL_VERTEX_SHADER)
        FRAGMENT_SHADER = shaders.compileShader("""
        #version 120
        void main() 
        {
            gl_FragColor = vec4(0, 1, 0, 1);
        }
        """, GL_FRAGMENT_SHADER)
        self.shader = shaders.compileProgram(VERTEX_SHADER,FRAGMENT_SHADER)
        self.vbo = vbo.VBO(np.array([
            [  0, 1, 0 ],
            [ -1,-1, 0 ],
            [  1,-1, 0 ],
        ],'f'))


    def OnDraw(self):
        self.OnSize()
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
        shaders.glUseProgram(self.shader)
        self.vbo.bind()
        glEnableClientState(GL_VERTEX_ARRAY)
        glVertexPointerf(self.vbo)
        glDrawArrays(GL_TRIANGLES, 0, 9)
        self.vbo.unbind()
        glDisableClientState(GL_VERTEX_ARRAY)
        shaders.glUseProgram(0)
        self.SwapBuffers()

    def OnSize(self):
        size = self.size = self.GetClientSize()
        glViewport(0, 0, size.width, size.height)

class MyApp(wx.App):
    def __init__(self):
        wx.App.__init__(self)

    def OnInit(self):
        frame = wx.Frame(None, title="OpenGL Test", size=(400, 300))
        frame.Show(True)
        c = MyCanvas(frame)
        return True

app = MyApp()
app.MainLoop()

Hope it helps!

Yes, your code is running well and help me. My code is old and I don't know all the changes make under develpment of python modules used into this source code. Feel free do add any infos. Thank you. — Cătălin George Feștilă, Sep 21 '16 at 17:50

pyOpenGL check for bool

1 Answers1