1clip3d_f(3)                     Allegro manual                     clip3d_f(3)
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NAME

6       clip3d_f  -  Clips  the polygon given in vtx using floating point math,
7       Allegro game programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       int clip3d_f(int type, float min_z, float max_z, int  vc,  const  V3D_f
14       *vtx[], V3D_f *vout[], V3D_f *vtmp[], int out[]);
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DESCRIPTION

17       Clips  the  polygon given in `vtx'. The number of vertices is `vc', the
18       result goes in `vout', and `vtmp' and `out'  are  needed  for  internal
19       purposes.  The pointers in `vtx', `vout' and `vtmp' must point to valid
20       V3D_f structures.
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22       As additional vertices may appear in the process of  clipping,  so  the
23       size  of  `vout',  `vtmp'  and `out' should be at least vc * (1.5 ^ n),
24       where `n' is the number of clipping planes (5 or 6),  and  `^'  denotes
25       "to the power of".
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27       The   frustum   (viewing   volume)   is   defined  by  -z<x<z,  -z<y<z,
28       0<min_z<z<max_z. If  max_z<=min_z, the z<max_z clipping is not done. As
29       you  can see, clipping is done in the camera space, with perspective in
30       mind, so this routine should be  called  after  you  apply  the  camera
31       matrix,  but  before  the perspective projection. The routine will cor‐
32       rectly interpolate u, v, and c in the  vertex  structure.  However,  no
33       provision is made for high/truecolor GCOL.
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RETURN VALUE

36       Returns the number of vertices after clipping is done.
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SEE ALSO

40       polygon3d(3), clip3d(3), excamera(3), exscn3d(3)
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44Allegro                          version 4.4.3                     clip3d_f(3)
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