Bin Exporter

[anamous]

As a way of exporting arbitary animated meshes to Maya/Max etc., I think that the realflow mesh BIN format isn't bad. However, I'm stuck on getting a simple python SOP to export it. Could be something obviously wrong.

this is the format description

(Begin of file)
[unsigned int]                      ; ID code = 0xDADADADA
[unsigned int]                      ; version = 4
[unsigned int]                      ; geometry chunk code = 0xCCCCCCCC (*)
[int]                               ; number of vertices
      loop for [number of vertices]
        [float]                     ; X coordinate
        [float]                     ; Y coordinate
        [float]                     ; Z coordinate
      endloop
[int]                               ; number of faces
      loop for [number of faces]
        [int]                       ; vertex index
        [int]                       ; vertex index
        [int]                       ; vertex index
      endloop

[unsigned int] ; code = 0xDEDEDEDE (end of file mark)
(End of file)

Here's my quick and dirty shot at an exporter:

# This code is called when instances of this SOP cook.
geo = hou.pwd().geometry()

formatID  = 0xDADADADA
formatVer = 4
formatGeo = 0xCCCCCCCC
formatEnd = 0xDEDEDEDE

import struct
from math import floor

filename = hou.Node.evalParm(hou.pwd(), "binFile")

f = open(filename, 'wb')

f.write(struct.pack('I',formatID))
f.write(struct.pack('I',formatVer))
f.write(struct.pack('I',formatGeo))

np = len(geo.points())

f.write(struct.pack('I',np))

# write vertices

for fac in geo.prims():
    verts = fac.vertices()
    for vert in verts:
        pt = vert.point()
        f.write(struct.pack('f',pt.position()[0]))
        f.write(struct.pack('f',pt.position()[1]))
        f.write(struct.pack('f',pt.position()[2]))

nf = len(geo.prims())

f.write(struct.pack('I',nf))

# write faces

for fac in geo.prims():
    vrts = fac.vertices()
    f.write(struct.pack('i',vrts[0].number()))
    f.write(struct.pack('i',vrts[1].number()))
    f.write(struct.pack('i',vrts[2].number()))

f.write(struct.pack('I',formatEnd))
f.close()

It's writing a file alright, but it doesn't seem to be a correct file.. Any ideas? And yes, it expects triangles as input geometry.

[dmaas]

Are you writing the correct endianness?