[PyOpenGL-Users] New user trying tutorial

[Berlioz S. <roc...@gm...>]

I've been interested in attempting to use pyopengl and pygame together to
display 3D images and accelerate my programs.

I figured a logical first step would be to learn a bit about pyopengl, so I
tried the tutorial.

I successfully installed pyopengl on OSX 10.9, and ran the first tutorial.

However, the second (introducing color variations
http://pyopengl.sourceforge.net/context/tutorials/shader_2.html) fails with
a bus error 10.

Is there another tutorial I should follow/what mistake did I make that is
giving me a segfault?

Here is my code:



from OpenGLContext import testingcontext
BaseContext = testingcontext.getInteractive()
from OpenGL.GL import *
from OpenGL.arrays import vbo
from OpenGL.GL import shaders

import numpy as np


class TestContext(BaseContext):
def OnInit(self):
try:
VERTEX_SHADER = shaders.compileShader("""
                    varying vec4 vertex_color;
                    void main(){
                     gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
                     vertex_color = gl_Color;
                    }""", GL_VERTEX_SHADER)
FRAGMENT_SHADER = shaders.compileShader("""
                varying vec4 vertex_color;
                    void main(){
                     gl_FragColor = vertex_color;
                    }""", GL_FRAGMENT_SHADER)
self.shader = shaders.compileProgram(VERTEX_SHADER, FRAGMENT_SHADER)
except (GLError, RuntimeError) as err:
print "Shader compilation error:", err
raise
self.vbo = vbo.VBO(np.array([
                   [ 0, 1, 0, 0,1,0 ],
                   [-1,-1, 0, 1,1,0 ],
                   [ 1,-1, 0, 0,1,1 ],
                   [ 2,-1, 0, 1,0,0 ],
                   [ 4,-1, 0, 0,1,0 ],
                   [ 4, 1, 0, 0,0,1 ],
                   [ 2,-1, 0, 1,0,0 ],
                   [ 4, 1, 0, 0,0,1 ],
                   [ 2, 1, 0, 0,1,1 ],
                   ],'f') )
def Render(self, mode):
glUseProgram(self.shader)
try:
self.vbo.bind()
try:
glEnableClientState(GL_VERTEX_ARRAY)
glEnableClientState(GL_COLOR_ARRAY)
#glVertexPointerf(self.vbo)
glColorPointer(3, GL_INT, 24, self.vbo+12)
glDrawArrays(GL_TRIANGLES, 0, 9)
finally:
self.vbo.unbind()
glDisableClientState(GL_VERTEX_ARRAY)
glDisableClientState(GL_COLOR_ARRAY)
finally:
shaders.glUseProgram(0)

if __name__ == "__main__":
TestContext.ContextMainLoop()