gistfile1.py

def myNormalize(myVec):
    myVec.normalize()
    return myVec

def create_mesh(parentnp, debug=False):
    '''This creates a simple 17x17 grid mesh for the sides of our cube.
    The ultimate goal is to use a LOD system, probably based on quadtrees.
    If debug is true then we get a color gradiant on our vertexes.'''
    x = -1.0
    y = -1.0
    vertex_count = 0
    u = 0.0
    v = 0.0

    WIDTH_STEP = 2/16.0

    while y <= 1.0:
        while x <= 1.0:
            vertex.addData3f(x, y, 0)
            normal.addData3f(myNormalize((Vec3(2*x-1, 2*y-1, 2*0-1))))
            if debug:
                color.addData4f(1.0, u, v, 1.0)
            texcoord.addData2f(u, v)
            vertex_count += 1
            x += WIDTH_STEP
            u += WIDTH_STEP/2.0
        x = -1.0
        u = 0
        y += WIDTH_STEP
        v += WIDTH_STEP/2.0

    print vertex_count
    triangles = []

    for y in range(0, 16):
        for x in range(0, 16):
            v = 17 * y + x
            tri = GeomTriangles(Geom.UHDynamic)
            tri.addVertex(v)
            tri.addVertex(v+1)
            tri.addVertex(v+17)
            tri.closePrimitive()
            triangles.append(tri)

            tri = GeomTriangles(Geom.UHDynamic)
            tri.addVertex(v+1)
            tri.addVertex(v+18)
            tri.addVertex(v+17)
            
            tri.closePrimitive()
            triangles.append(tri)

    mesh = Geom(vdata)
    for t in triangles:
        mesh.addPrimitive(t)
    mnode = GeomNode('quadface')
    mnode.addGeom(mesh)
    nodePath = parentnp.attachNewNode(mnode)
    return nodePath