2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
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22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
30 #include "main/glheader.h"
31 #include "main/config.h"
32 #include "math/m_vector.h"
33 #include "math/m_matrix.h"
36 #define _XFORMAPI _ASMAPI
37 #define _XFORMAPIP _ASMAPIP
45 _math_init_transformation(void);
48 /* KW: Clip functions now do projective divide as well. The projected
49 * coordinates are very useful to us because they let us cull
50 * backfaces and eliminate vertices from lighting, fogging, etc
51 * calculations. Despite the fact that this divide could be done one
52 * day in hardware, we would still have a reason to want to do it here
53 * as long as those other calculations remain in software.
55 * Clipping is a convenient place to do the divide on x86 as it should be
56 * possible to overlap with integer outcode calculations.
58 * There are two cases where we wouldn't want to do the divide in cliptest:
59 * - When we aren't clipping. We still might want to cull backfaces
60 * so the divide should be done elsewhere. This currently never
63 * - When culling isn't likely to help us, such as when the GL culling
64 * is disabled and we not lighting or are only lighting
65 * one-sided. In this situation, backface determination provides
66 * us with no useful information. A tricky case to detect is when
67 * all input data is already culled, although hopefully the
68 * application wouldn't turn on culling in such cases.
70 * We supply a buffer to hold the [x/w,y/w,z/w,1/w] values which
71 * are the result of the projection. This is only used in the
72 * 4-vector case - in other cases, we just use the clip coordinates
73 * as the projected coordinates - they are identical.
75 * This is doubly convenient because it means the Win[] array is now
76 * of the same stride as all the others, so I can now turn map_vertices
77 * into a straight-forward matrix transformation, with asm acceleration
78 * automatically available.
81 /* Vertex buffer clipping flags
83 #define CLIP_RIGHT_SHIFT 0
84 #define CLIP_LEFT_SHIFT 1
85 #define CLIP_TOP_SHIFT 2
86 #define CLIP_BOTTOM_SHIFT 3
87 #define CLIP_NEAR_SHIFT 4
88 #define CLIP_FAR_SHIFT 5
90 #define CLIP_RIGHT_BIT 0x01
91 #define CLIP_LEFT_BIT 0x02
92 #define CLIP_TOP_BIT 0x04
93 #define CLIP_BOTTOM_BIT 0x08
94 #define CLIP_NEAR_BIT 0x10
95 #define CLIP_FAR_BIT 0x20
96 #define CLIP_USER_BIT 0x40
97 #define CLIP_CULL_BIT 0x80
98 #define CLIP_FRUSTUM_BITS 0x3f
101 typedef GLvector4f
* (_XFORMAPIP clip_func
)( GLvector4f
*vClip
,
107 typedef void (*dotprod_func
)( GLfloat
*out
,
109 CONST GLvector4f
*coord_vec
,
110 CONST GLfloat plane
[4] );
112 typedef void (*vec_copy_func
)( GLvector4f
*to
,
113 CONST GLvector4f
*from
);
118 * Functions for transformation of normals in the VB.
120 typedef void (_NORMAPIP normal_func
)( CONST GLmatrix
*mat
,
122 CONST GLvector4f
*in
,
123 CONST GLfloat lengths
[],
127 /* Flags for selecting a normal transformation function.
129 #define NORM_RESCALE 0x1 /* apply the scale factor */
130 #define NORM_NORMALIZE 0x2 /* normalize */
131 #define NORM_TRANSFORM 0x4 /* apply the transformation matrix */
132 #define NORM_TRANSFORM_NO_ROT 0x8 /* apply the transformation matrix */
137 /* KW: New versions of the transform function allow a mask array
138 * specifying that individual vector transform should be skipped
139 * when the mask byte is zero. This is always present as a
140 * parameter, to allow a unified interface.
142 typedef void (_XFORMAPIP transform_func
)( GLvector4f
*to_vec
,
144 CONST GLvector4f
*from_vec
);
147 extern dotprod_func _mesa_dotprod_tab
[5];
148 extern vec_copy_func _mesa_copy_tab
[0x10];
149 extern vec_copy_func _mesa_copy_clean_tab
[5];
150 extern clip_func _mesa_clip_tab
[5];
151 extern clip_func _mesa_clip_np_tab
[5];
152 extern normal_func _mesa_normal_tab
[0xf];
154 /* Use of 2 layers of linked 1-dimensional arrays to reduce
157 extern transform_func
*_mesa_transform_tab
[5];
161 #define TransformRaw( to, mat, from ) \
162 ( _mesa_transform_tab[(from)->size][(mat)->type]( to, (mat)->m, from ), \