prj/tech/libsrc/r3d/xfrmclip.c

   1 /*
   2  * $Source: x:/prj/tech/libsrc/r3d/RCS/xfrmclip.c $
   3  * $Revision: 1.7 $
   4  * $Author: KEVIN $
   5  * $Date: 1996/10/29 12:44:59 $
   6  *
   7  * Transform and projection definitions for clipping space
   8  *
   9  */
  10
  11
  12 #include <xfrmtab.h>
  13 #include <_xfrm.h>
  14 #include <clipcon_.h>
  15 #include <matrix.h>
  16
  17 extern void r3_clipspace_code_points(int, r3s_point *); // HACK HACK HACK
  18
  19 // go through and transform all the points.
  20 // note that this also works for projection space, and
  21 // unscaled space, but not linear, I think.
  22 void r3_rotate_block_clip(int n, r3s_point *dst, mxs_vector *src)
  23 {
  24    uchar *cur, *last;
  25
  26    TEST_IN_BLOCK("r3_rotate_block_clip");
  27
  28    cur = (uchar *)(&(dst->p));
  29    last = cur + n * r3d_glob.cur_stride;
  30
  31    while (cur < last) {
  32       mx_trans_mul_vec((mxs_vector *)cur, X2TRANS(&cx.o2c), src++);
  33       cur += r3d_glob.cur_stride;
  34    }
  35
  36    if (r3d_clip_mode == R3_CLIP)
  37       r3_clipspace_code_points(n, dst);
  38 }
  39
  40 // This is only for clipped
  41 void r3_project_block_clip(int n, r3s_point *p_list)
  42 {
  43    uchar *cur, *last;
  44
  45    TEST_IN_BLOCK("r3_project_block_clip");
  46
  47    cur = (uchar *)p_list;
  48    last = cur + n * r3d_glob.cur_stride;
  49
  50    while (cur < last) {
  51       r3s_point *p = (r3s_point *)cur;
  52       double w;
  53
  54       cur += r3d_glob.cur_stride;
  55
  56       w = 1.0/p->p.z; // w is 1/z;
  57
  58       p->grp.sx = (int)((p->p.x * w * r3d_glob.x_prj) + r3d_glob.x_off);
  59       p->grp.sy = (int)((p->p.y * w * r3d_glob.y_prj) + r3d_glob.y_off);
  60       p->grp.w = w;
  61    }
  62 }
  63
  64 r3s_xform_tab r3d_xform_tab_clip = {
  65    r3_rotate_block_clip,
  66    r3_project_block_clip
  67 };