C++程序  |  103行  |  3.07 KB


/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2001  Brian Paul   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, sublicense,
 * 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 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 NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * New (3.1) transformation code written by Keith Whitwell.
 */


/* Note - respects the stride of the output vector.
 */
static void TAG(dotprod_vec2)( GLfloat *out,
			       GLuint outstride,
			       const GLvector4f *coord_vec,
			       const GLfloat plane[4] )
{
   GLuint stride = coord_vec->stride;
   GLfloat *coord = coord_vec->start;
   GLuint count = coord_vec->count;

   GLuint i;

   const GLfloat plane0 = plane[0], plane1 = plane[1], plane3 = plane[3];

   for (i=0;i<count;i++,STRIDE_F(coord,stride),STRIDE_F(out,outstride)) {
      *out = (coord[0] * plane0 +
	      coord[1] * plane1 +
	      plane3);
   }
}

static void TAG(dotprod_vec3)( GLfloat *out,
			       GLuint outstride,
			       const GLvector4f *coord_vec,
			       const GLfloat plane[4] )
{
   GLuint stride = coord_vec->stride;
   GLfloat *coord = coord_vec->start;
   GLuint count = coord_vec->count;

   GLuint i;

   const GLfloat plane0 = plane[0], plane1 = plane[1], plane2 = plane[2];
   const GLfloat plane3 = plane[3];

   for (i=0;i<count;i++,STRIDE_F(coord,stride),STRIDE_F(out,outstride)) {
      *out = (coord[0] * plane0 +
	      coord[1] * plane1 +
	      coord[2] * plane2 +
	      plane3);
   }
}

static void TAG(dotprod_vec4)( GLfloat *out,
			       GLuint outstride,
			       const GLvector4f *coord_vec,
			       const GLfloat plane[4] )
{
   GLuint stride = coord_vec->stride;
   GLfloat *coord = coord_vec->start;
   GLuint count = coord_vec->count;
   GLuint i;

   const GLfloat plane0 = plane[0], plane1 = plane[1], plane2 = plane[2];
   const GLfloat plane3 = plane[3];

   for (i=0;i<count;i++,STRIDE_F(coord,stride),STRIDE_F(out,outstride)) {
      *out = (coord[0] * plane0 +
	      coord[1] * plane1 +
	      coord[2] * plane2 +
	      coord[3] * plane3);
   }
}


static void TAG(init_dotprod)( void )
{
   _mesa_dotprod_tab[2] = TAG(dotprod_vec2);
   _mesa_dotprod_tab[3] = TAG(dotprod_vec3);
   _mesa_dotprod_tab[4] = TAG(dotprod_vec4);
}