[PyOpenGL-Users] glVertexAttribPointer Problem

[Thomas <p_t...@gm...>]

Hello,

I'm trying to use glVertexAttribPointer and interleaved vertex data.

// simple coordinate cross: vertex0, color0, ...
data = [0.0, 0.0, 0.0, 1.0, 0.0, 0.0, # x0
              1.0, 0.0, 0.0, 1.0, 0.0, 0.0, # x1
              0.0, 0.0, 0.0, 0.0, 1.0, 0.0, # y0
              0.0, 1.0, 0.0, 0.0, 1.0, 0.0, # y1
              0.0, 0.0, 0.0, 0.0, 0.0, 1.0, # z0
              0.0, 0.0, 1.0, 0.0, 0.0, 1.0] # z1

buffer = glGenBuffers(1)
glBindBuffer(GL_ARRAY_BUFFER, buffer)
glBufferData(GL_ARRAY_BUFFER, numpy.array(cross, numpy.float32), 
GL_STATIC_DRAW)

# attributes are queried by glGetAttribLocation after shaders are linked
glVertexAttribPointer(attributes['coord'], GLint(3), GL_FLOAT, GL_FALSE, 
GLsizei(6 * 4), ctypes.c_void_p(0))
glVertexAttribPointer(attributes['color'], GLint(3), GL_FLOAT, GL_FALSE, 
GLsizei(6 * 4), ctypes.c_void_p(3))

for index in attributes.values():
             glEnableVertexAttribArray(index)

In my vertex shader I have:
attribute vec3 coord;
attribute vec3 color;

Vertex data is correct, but "vec3 color" is always (0.0, 0.0, 0.0)

Is it a problem with pyopengl or did I miss something in my setup?

-Thomas