static void
test_clip_plane (void)
{
  GLdouble plane[] = {0.1, 0.2, 0.3, 0.4};

  glClipPlane (GL_CLIP_PLANE0, plane);
  glEnable (GL_CLIP_PLANE0);
  tri ();
  glDisable (GL_CLIP_PLANE0);
}

#define R300_VAP_PVS_UPLOAD_ADDRESS         0x2200
#       define R300_PVS_UPLOAD_PROGRAM           0x00000000
#       define R300_PVS_UPLOAD_PARAMETERS        0x00000200
#       define R300_PVS_UPLOAD_POINTSIZE         0x00000406

dump_packet0: type = 0 cnt = 0 bit15 = 0 reg = 0x2200
dump_reg: key = 0x2200 val = 0x00000400
dump_packet0: type = 0 cnt = 3 bit15 = 1 reg = 0x2208
dump_reg: key = 0x2208 val = 0x3dcccccd
dump_reg: key = 0x2208 val = 0x3e4ccccd
dump_reg: key = 0x2208 val = 0x3e99999a
dump_reg: key = 0x2208 val = 0x3ecccccd

(gdb) p/f 0x3dcccccd
$1 = 0.100000001
(gdb) p/f 0x3e4ccccd
$2 = 0.200000003
(gdb) p/f 0x3e99999a
$3 = 0.300000012
(gdb) p/f 0x3ecccccd
$4 = 0.400000006