src/mesa/tnl/t_vb_normals.c

   1 /* $Id: t_vb_normals.c,v 1.16 2002/10/24 23:57:25 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  4.1
   6  *
   7  * Copyright (C) 1999-2002  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * Authors:
  27  *    Keith Whitwell <keithw@valinux.com>
  28  */
  29
  30
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "macros.h"
  35 #include "imports.h"
  36 #include "mmath.h"
  37 #include "mtypes.h"
  38
  39 #include "math/m_xform.h"
  40
  41 #include "t_context.h"
  42 #include "t_pipeline.h"
  43
  44
  45
  46 struct normal_stage_data {
  47    normal_func NormalTransform;
  48    GLvector4f normal;
  49 };
  50
  51 #define NORMAL_STAGE_DATA(stage) ((struct normal_stage_data *)stage->privatePtr)
  52
  53
  54
  55
  56 static GLboolean run_normal_stage( GLcontext *ctx,
  57                                    struct gl_pipeline_stage *stage )
  58 {
  59    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
  60    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  61
  62    ASSERT(store->NormalTransform);
  63
  64    if (stage->changed_inputs) {
  65       /* We can only use the display list's saved normal lengths if we've
  66        * got a transformation matrix with uniform scaling.
  67        */
  68       const GLfloat *lengths;
  69       if (ctx->ModelviewMatrixStack.Top->flags & MAT_FLAG_GENERAL_SCALE)
  70          lengths = NULL;
  71       else
  72          lengths = VB->NormalLengthPtr;
  73
  74       store->NormalTransform( ctx->ModelviewMatrixStack.Top,
  75                               ctx->_ModelViewInvScale,
  76                               VB->NormalPtr,  /* input normals */
  77                               lengths,
  78                               &store->normal ); /* resulting normals */
  79    }
  80
  81    VB->NormalPtr = &store->normal;
  82    VB->NormalLengthPtr = 0;     /* no longer valid */
  83    return GL_TRUE;
  84 }
  85
  86
  87 static GLboolean run_validate_normal_stage( GLcontext *ctx,
  88                                             struct gl_pipeline_stage *stage )
  89 {
  90    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
  91
  92    ASSERT(ctx->_NeedNormals);
  93
  94    if (ctx->_NeedEyeCoords) {
  95       GLuint transform = NORM_TRANSFORM_NO_ROT;
  96
  97       if (ctx->ModelviewMatrixStack.Top->flags & (MAT_FLAG_GENERAL |
  98                                   MAT_FLAG_ROTATION |
  99                                   MAT_FLAG_GENERAL_3D |
 100                                   MAT_FLAG_PERSPECTIVE))
 101          transform = NORM_TRANSFORM;
 102
 103
 104       if (ctx->Transform.Normalize) {
 105          store->NormalTransform = _mesa_normal_tab[transform | NORM_NORMALIZE];
 106       }
 107       else if (ctx->Transform.RescaleNormals &&
 108                ctx->_ModelViewInvScale != 1.0) {
 109          store->NormalTransform = _mesa_normal_tab[transform | NORM_RESCALE];
 110       }
 111       else {
 112          store->NormalTransform = _mesa_normal_tab[transform];
 113       }
 114    }
 115    else {
 116       if (ctx->Transform.Normalize) {
 117          store->NormalTransform = _mesa_normal_tab[NORM_NORMALIZE];
 118       }
 119       else if (!ctx->Transform.RescaleNormals &&
 120                ctx->_ModelViewInvScale != 1.0) {
 121          store->NormalTransform = _mesa_normal_tab[NORM_RESCALE];
 122       }
 123       else {
 124          store->NormalTransform = 0;
 125       }
 126    }
 127
 128    if (store->NormalTransform) {
 129       stage->run = run_normal_stage;
 130       return stage->run( ctx, stage );
 131    } else {
 132       stage->active = GL_FALSE; /* !!! */
 133       return GL_TRUE;
 134    }
 135 }
 136
 137
 138 static void check_normal_transform( GLcontext *ctx,
 139                                     struct gl_pipeline_stage *stage )
 140 {
 141    stage->active = ctx->_NeedNormals && !ctx->VertexProgram.Enabled;
 142    /* Don't clobber the initialize function:
 143     */
 144    if (stage->privatePtr)
 145       stage->run = run_validate_normal_stage;
 146 }
 147
 148
 149 static GLboolean alloc_normal_data( GLcontext *ctx,
 150                                  struct gl_pipeline_stage *stage )
 151 {
 152    TNLcontext *tnl = TNL_CONTEXT(ctx);
 153    struct normal_stage_data *store;
 154    stage->privatePtr = MALLOC(sizeof(*store));
 155    store = NORMAL_STAGE_DATA(stage);
 156    if (!store)
 157       return GL_FALSE;
 158
 159    _mesa_vector4f_alloc( &store->normal, 0, tnl->vb.Size, 32 );
 160
 161    /* Now run the stage.
 162     */
 163    stage->run = run_validate_normal_stage;
 164    return stage->run( ctx, stage );
 165 }
 166
 167
 168
 169 static void free_normal_data( struct gl_pipeline_stage *stage )
 170 {
 171    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
 172    if (store) {
 173       _mesa_vector4f_free( &store->normal );
 174       FREE( store );
 175       stage->privatePtr = NULL;
 176    }
 177 }
 178
 179 #define _TNL_NEW_NORMAL_TRANSFORM        (_NEW_MODELVIEW| \
 180                                           _NEW_TRANSFORM| \
 181                                           _MESA_NEW_NEED_NORMALS| \
 182                                           _MESA_NEW_NEED_EYE_COORDS)
 183
 184
 185
 186 const struct gl_pipeline_stage _tnl_normal_transform_stage =
 187 {
 188    "normal transform",          /* name */
 189    _TNL_NEW_NORMAL_TRANSFORM,   /* re-check */
 190    _TNL_NEW_NORMAL_TRANSFORM,   /* re-run */
 191    GL_FALSE,                    /* active? */
 192    VERT_BIT_NORMAL,             /* inputs */
 193    VERT_BIT_NORMAL,             /* outputs */
 194    0,                           /* changed_inputs */
 195    NULL,                        /* private data */
 196    free_normal_data,            /* destructor */
 197    check_normal_transform,      /* check */
 198    alloc_normal_data            /* run -- initially set to alloc */
 199 };