src/mesa/math/m_xform.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.3
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26
  27 #ifndef _M_XFORM_H
  28 #define _M_XFORM_H
  29
  30
  31 #include "main/compiler.h"
  32 #include "main/glheader.h"
  33 #include "math/m_matrix.h"
  34 #include "math/m_vector.h"
  35
  36 #ifdef USE_X86_ASM
  37 #define _XFORMAPI _ASMAPI
  38 #define _XFORMAPIP _ASMAPIP
  39 #else
  40 #define _XFORMAPI
  41 #define _XFORMAPIP *
  42 #endif
  43
  44
  45 extern void
  46 _math_init_transformation(void);
  47 extern void
  48 init_c_cliptest(void);
  49
  50 /* KW: Clip functions now do projective divide as well.  The projected
  51  * coordinates are very useful to us because they let us cull
  52  * backfaces and eliminate vertices from lighting, fogging, etc
  53  * calculations.  Despite the fact that this divide could be done one
  54  * day in hardware, we would still have a reason to want to do it here
  55  * as long as those other calculations remain in software.
  56  *
  57  * Clipping is a convenient place to do the divide on x86 as it should be
  58  * possible to overlap with integer outcode calculations.
  59  *
  60  * There are two cases where we wouldn't want to do the divide in cliptest:
  61  *    - When we aren't clipping.  We still might want to cull backfaces
  62  *      so the divide should be done elsewhere.  This currently never
  63  *      happens.
  64  *
  65  *    - When culling isn't likely to help us, such as when the GL culling
  66  *      is disabled and we not lighting or are only lighting
  67  *      one-sided.  In this situation, backface determination provides
  68  *      us with no useful information.  A tricky case to detect is when
  69  *      all input data is already culled, although hopefully the
  70  *      application wouldn't turn on culling in such cases.
  71  *
  72  * We supply a buffer to hold the [x/w,y/w,z/w,1/w] values which
  73  * are the result of the projection.  This is only used in the
  74  * 4-vector case - in other cases, we just use the clip coordinates
  75  * as the projected coordinates - they are identical.
  76  *
  77  * This is doubly convenient because it means the Win[] array is now
  78  * of the same stride as all the others, so I can now turn map_vertices
  79  * into a straight-forward matrix transformation, with asm acceleration
  80  * automatically available.
  81  */
  82
  83 /* Vertex buffer clipping flags
  84  */
  85 #define CLIP_RIGHT_SHIFT        0
  86 #define CLIP_LEFT_SHIFT         1
  87 #define CLIP_TOP_SHIFT          2
  88 #define CLIP_BOTTOM_SHIFT       3
  89 #define CLIP_NEAR_SHIFT         4
  90 #define CLIP_FAR_SHIFT          5
  91
  92 #define CLIP_RIGHT_BIT   0x01
  93 #define CLIP_LEFT_BIT    0x02
  94 #define CLIP_TOP_BIT     0x04
  95 #define CLIP_BOTTOM_BIT  0x08
  96 #define CLIP_NEAR_BIT    0x10
  97 #define CLIP_FAR_BIT     0x20
  98 #define CLIP_USER_BIT    0x40
  99 #define CLIP_CULL_BIT    0x80
 100 #define CLIP_FRUSTUM_BITS    0x3f
 101
 102
 103 typedef GLvector4f * (_XFORMAPIP clip_func)( GLvector4f *vClip,
 104                                              GLvector4f *vProj,
 105                                              GLubyte clipMask[],
 106                                              GLubyte *orMask,
 107                                              GLubyte *andMask,
 108                                              GLboolean viewport_z_clip );
 109
 110 typedef void (*dotprod_func)( GLfloat *out,
 111                               GLuint out_stride,
 112                               const GLvector4f *coord_vec,
 113                               const GLfloat plane[4] );
 114
 115 typedef void (*vec_copy_func)( GLvector4f *to,
 116                                const GLvector4f *from );
 117
 118
 119
 120 /*
 121  * Functions for transformation of normals in the VB.
 122  */
 123 typedef void (_NORMAPIP normal_func)( const GLmatrix *mat,
 124                                       GLfloat scale,
 125                                       const GLvector4f *in,
 126                                       const GLfloat lengths[],
 127                                       GLvector4f *dest );
 128
 129
 130 /* Flags for selecting a normal transformation function.
 131  */
 132 #define NORM_RESCALE   0x1              /* apply the scale factor */
 133 #define NORM_NORMALIZE 0x2              /* normalize */
 134 #define NORM_TRANSFORM 0x4              /* apply the transformation matrix */
 135 #define NORM_TRANSFORM_NO_ROT 0x8       /* apply the transformation matrix */
 136
 137
 138
 139
 140 /* KW: New versions of the transform function allow a mask array
 141  *     specifying that individual vector transform should be skipped
 142  *     when the mask byte is zero.  This is always present as a
 143  *     parameter, to allow a unified interface.
 144  */
 145 typedef void (_XFORMAPIP transform_func)( GLvector4f *to_vec,
 146                                           const GLfloat m[16],
 147                                           const GLvector4f *from_vec );
 148
 149
 150 extern dotprod_func  _mesa_dotprod_tab[5];
 151 extern vec_copy_func _mesa_copy_tab[0x10];
 152 extern vec_copy_func _mesa_copy_clean_tab[5];
 153 extern clip_func     _mesa_clip_tab[5];
 154 extern clip_func     _mesa_clip_np_tab[5];
 155 extern normal_func   _mesa_normal_tab[0xf];
 156
 157 /* Use of 2 layers of linked 1-dimensional arrays to reduce
 158  * cost of lookup.
 159  */
 160 extern transform_func *_mesa_transform_tab[5];
 161
 162
 163
 164 #define TransformRaw( to, mat, from ) \
 165    ( _mesa_transform_tab[(from)->size][(mat)->type]( to, (mat)->m, from ), \
 166      (to) )
 167
 168
 169 #endif