m_xform.c

mesa-6.5-minigui源码

/*
 * Mesa 3-D graphics library
 * Version:  5.1
 *
 * Copyright (C) 1999-2003  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
 * BRIAN PAUL 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.
 */


/*
 * Matrix/vertex/vector transformation stuff
 *
 *
 * NOTES:
 * 1. 4x4 transformation matrices are stored in memory in column major order.
 * 2. Points/vertices are to be thought of as column vectors.
 * 3. Transformation of a point p by a matrix M is: p' = M * p
 */

#include "glheader.h"
#include "macros.h"

#include "m_eval.h"
#include "m_matrix.h"
#include "m_translate.h"
#include "m_xform.h"
#include "mathmod.h"


#ifdef DEBUG_MATH
#include "m_debug.h"
#endif

#ifdef USE_X86_ASM
#include "x86/common_x86_asm.h"
#endif

#ifdef USE_X86_64_ASM
#include "x86-64/x86-64.h"
#endif

#ifdef USE_SPARC_ASM
#include "sparc/sparc.h"
#endif

#ifdef USE_PPC_ASM
#include "ppc/common_ppc_features.h"
#endif

clip_func _mesa_clip_tab[5];
clip_func _mesa_clip_np_tab[5];
dotprod_func _mesa_dotprod_tab[5];
vec_copy_func _mesa_copy_tab[0x10];
normal_func _mesa_normal_tab[0xf];
transform_func *_mesa_transform_tab[5];


/* Raw data format used for:
 *    - Object-to-eye transform prior to culling, although this too
 *      could be culled under some circumstances.
 *    - Eye-to-clip transform (via the function above).
 *    - Cliptesting
 *    - And everything else too, if culling happens to be disabled.
 *
 * GH: It's used for everything now, as clipping/culling is done
 *     elsewhere (most often by the driver itself).
 */
#define TAG(x) x
#define TAG2(x,y) x##y
#define STRIDE_LOOP for ( i = 0 ; i < count ; i++, STRIDE_F(from, stride) )
#define LOOP for ( i = 0 ; i < n ; i++ )
#define ARGS
#include "m_xform_tmp.h"
#include "m_clip_tmp.h"
#include "m_norm_tmp.h"
#include "m_dotprod_tmp.h"
#include "m_copy_tmp.h"
#undef TAG
#undef TAG2
#undef LOOP
#undef ARGS




GLvector4f *_mesa_project_points( GLvector4f *proj_vec,
				  const GLvector4f *clip_vec )
{
   const GLuint stride = clip_vec->stride;
   const GLfloat *from = (GLfloat *)clip_vec->start;
   const GLuint count = clip_vec->count;
   GLfloat (*vProj)[4] = (GLfloat (*)[4])proj_vec->start;
   GLuint i;

   for (i = 0 ; i < count ; i++, STRIDE_F(from, stride))
   {
	 GLfloat oow = 1.0F / from[3];
	 vProj[i][3] = oow;
	 vProj[i][0] = from[0] * oow;
	 vProj[i][1] = from[1] * oow;
	 vProj[i][2] = from[2] * oow;
   }

   proj_vec->flags |= VEC_SIZE_4;
   proj_vec->size = 3;
   proj_vec->count = clip_vec->count;
   return proj_vec;
}






/*
 * Transform a 4-element row vector (1x4 matrix) by a 4x4 matrix.  This
 * function is used for transforming clipping plane equations and spotlight
 * directions.
 * Mathematically,  u = v * m.
 * Input:  v - input vector
 *         m - transformation matrix
 * Output:  u - transformed vector
 */
void _mesa_transform_vector( GLfloat u[4], const GLfloat v[4], const GLfloat m[16] )
{
   GLfloat v0=v[0], v1=v[1], v2=v[2], v3=v[3];
#define M(row,col)  m[row + col*4]
   u[0] = v0 * M(0,0) + v1 * M(1,0) + v2 * M(2,0) + v3 * M(3,0);
   u[1] = v0 * M(0,1) + v1 * M(1,1) + v2 * M(2,1) + v3 * M(3,1);
   u[2] = v0 * M(0,2) + v1 * M(1,2) + v2 * M(2,2) + v3 * M(3,2);
   u[3] = v0 * M(0,3) + v1 * M(1,3) + v2 * M(2,3) + v3 * M(3,3);
#undef M
}


/* Useful for one-off point transformations, as in clipping.
 * Note that because the matrix isn't analysed we do too many
 * multiplies, and that the result is always 4-clean.
 */
void _mesa_transform_point_sz( GLfloat Q[4], const GLfloat M[16],
			    const GLfloat P[4], GLuint sz )
{
   if (Q == P)
      return;

   if (sz == 4)
   {
      Q[0] = M[0] * P[0] + M[4] * P[1] + M[8] *  P[2] + M[12] * P[3];
      Q[1] = M[1] * P[0] + M[5] * P[1] + M[9] *  P[2] + M[13] * P[3];
      Q[2] = M[2] * P[0] + M[6] * P[1] + M[10] * P[2] + M[14] * P[3];
      Q[3] = M[3] * P[0] + M[7] * P[1] + M[11] * P[2] + M[15] * P[3];
   }
   else if (sz == 3)
   {
      Q[0] = M[0] * P[0] + M[4] * P[1] + M[8] *  P[2] + M[12];
      Q[1] = M[1] * P[0] + M[5] * P[1] + M[9] *  P[2] + M[13];
      Q[2] = M[2] * P[0] + M[6] * P[1] + M[10] * P[2] + M[14];
      Q[3] = M[3] * P[0] + M[7] * P[1] + M[11] * P[2] + M[15];
   }
   else if (sz == 2)
   {
      Q[0] = M[0] * P[0] + M[4] * P[1] +                M[12];
      Q[1] = M[1] * P[0] + M[5] * P[1] +                M[13];
      Q[2] = M[2] * P[0] + M[6] * P[1] +                M[14];
      Q[3] = M[3] * P[0] + M[7] * P[1] +                M[15];
   }
   else if (sz == 1)
   {
      Q[0] = M[0] * P[0] +                              M[12];
      Q[1] = M[1] * P[0] +                              M[13];
      Q[2] = M[2] * P[0] +                              M[14];
      Q[3] = M[3] * P[0] +                              M[15];
   }
}


/*
 * This is called only once.  It initializes several tables with pointers
 * to optimized transformation functions.  This is where we can test for
 * AMD 3Dnow! capability, Intel SSE, etc. and hook in the right code.
 */
void
_math_init_transformation( void )
{
   init_c_transformations();
   init_c_norm_transform();
   init_c_cliptest();
   init_copy0();
   init_dotprod();

#ifdef DEBUG_MATH
   _math_test_all_transform_functions( "default" );
   _math_test_all_normal_transform_functions( "default" );
   _math_test_all_cliptest_functions( "default" );
#endif

#ifdef USE_X86_ASM
   _mesa_init_all_x86_transform_asm();
#elif defined( USE_SPARC_ASM )
   _mesa_init_all_sparc_transform_asm();
#elif defined( USE_PPC_ASM )
   _mesa_init_all_ppc_transform_asm();
#elif defined( USE_X86_64_ASM )
   _mesa_init_all_x86_64_transform_asm();
#endif
}

void
_math_init( void )
{
   _math_init_transformation();
   _math_init_translate();
   _math_init_eval();
}