xref: /external/mesa3d/src/gallium/auxiliary/draw/draw_cliptest_tmp.h

/**************************************************************************
 *
 * Copyright 2010, VMware, inc.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
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 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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static boolean TAG(do_cliptest)( struct pt_post_vs *pvs,
                                 struct draw_vertex_info *info )
{
   struct vertex_header *out = info->verts;
   const float *scale = pvs->draw->viewport.scale;
   const float *trans = pvs->draw->viewport.translate;
   /* const */ float (*plane)[4] = pvs->draw->plane;
   const unsigned pos = draw_current_shader_position_output(pvs->draw);
   const unsigned ef = pvs->draw->vs.edgeflag_output;
   const unsigned nr = pvs->draw->nr_planes;
   const unsigned flags = (FLAGS);
   unsigned need_pipeline = 0;
   unsigned j;

   for (j = 0; j < info->count; j++) {
      float *position = out->data[pos];
      unsigned mask = 0x0;

      initialize_vertex_header(out);

      if (flags & (DO_CLIP_XY | DO_CLIP_FULL_Z | DO_CLIP_HALF_Z | DO_CLIP_USER)) {
         out->clip[0] = position[0];
         out->clip[1] = position[1];
         out->clip[2] = position[2];
         out->clip[3] = position[3];

         /* Do the hardwired planes first:
          */
         if (flags & DO_CLIP_XY) {
            if (-position[0] + position[3] < 0) mask |= (1<<0);
            if ( position[0] + position[3] < 0) mask |= (1<<1);
            if (-position[1] + position[3] < 0) mask |= (1<<2);
            if ( position[1] + position[3] < 0) mask |= (1<<3);
         }

         /* Clip Z planes according to full cube, half cube or none.
          */
         if (flags & DO_CLIP_FULL_Z) {
            if ( position[2] + position[3] < 0) mask |= (1<<4);
            if (-position[2] + position[3] < 0) mask |= (1<<5);
         }
         else if (flags & DO_CLIP_HALF_Z) {
            if ( position[2]               < 0) mask |= (1<<4);
            if (-position[2] + position[3] < 0) mask |= (1<<5);
         }

         if (flags & DO_CLIP_USER) {
            unsigned i;
            for (i = 6; i < nr; i++) {
               if (dot4(position, plane[i]) < 0)
                  mask |= (1<<i);
            }
         }

         out->clipmask = mask;
         need_pipeline |= out->clipmask;
      }

      if ((flags & DO_VIEWPORT) && mask == 0)
      {
	 /* divide by w */
	 float w = 1.0f / position[3];

	 /* Viewport mapping */
	 position[0] = position[0] * w * scale[0] + trans[0];
	 position[1] = position[1] * w * scale[1] + trans[1];
	 position[2] = position[2] * w * scale[2] + trans[2];
	 position[3] = w;
      }

      if ((flags & DO_EDGEFLAG) && ef) {
         const float *edgeflag = out->data[ef];
         out->edgeflag = !(edgeflag[0] != 1.0f);
         need_pipeline |= !out->edgeflag;
      }

      out = (struct vertex_header *)( (char *)out + info->stride );
   }

   return need_pipeline != 0;
}


#undef FLAGS
#undef TAG