I am currently programming a game with PyOpenGL with PyGame, and when using Vertex Buffers, graphical glitches occur. The glitches include lines being drawn between each model when it shouldn't. I have found that alternating between Ground() and GroundVBO() does not cause any graphical glitches most of the time. Is there anything that I am missing?
global vbo
vbo = 0
def Ground():
glBegin(GL_LINES)
for edge in ground_edges:
for vertex in edge:
glVertex3fv(ground_verticies[vertex])
glEnd()
def GroundVBO():
for edge in ground_edges:
for vertex in edge:
ground_noot = glVertex3fv(ground_verticies[vertex])
vbo = glGenBuffers(1)
glBindBuffer (GL_ARRAY_BUFFER, vbo)
glBufferData (GL_ARRAY_BUFFER, len(ground_verticies)*4, ground_noot, GL_STATIC_DRAW)
glVertexPointer (3, GL_FLOAT, 0, None)
glDrawArrays(GL_LINES, 0, 300)
If you want to use fixed function attributes, then you have to enable the client-side capability by glEnableClientState
.
Specifying the vertices by glVertex3fv
in a loop is superfluous. Specifying a vertex outside a glBegin
/glEnd
sequence results in undefined behavior.
The last parameter to glDrawArrays
is the number of vertex coordinates:
def GroundVBO():
vbo = glGenBuffers(1)
glBindBuffer(GL_ARRAY_BUFFER, vbo)
glBufferData(GL_ARRAY_BUFFER, len(ground_verticies)*4, ground_noot, GL_STATIC_DRAW)
glEnableClientState(GL_VERTEX_ARRAY)
glVertexPointer(3, GL_FLOAT, 0, None)
glDrawArrays(GL_LINES, 0, len(ground_verticies))
glDisableClientState(GL_VERTEX_ARRAY)