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