src/mesa/tnl/t_vb_normals.c

   1
   2 /*
   3  * Mesa 3-D graphics library
   4  * Version:  5.1
   5  *
   6  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  * Authors:
  26  *    Keith Whitwell <keith@tungstengraphics.com>
  27  */
  28
  29
  30 #include "glheader.h"
  31 #include "colormac.h"
  32 #include "context.h"
  33 #include "macros.h"
  34 #include "imports.h"
  35 #include "mtypes.h"
  36
  37 #include "math/m_xform.h"
  38
  39 #include "t_context.h"
  40 #include "t_pipeline.h"
  41
  42
  43
  44 struct normal_stage_data {
  45    normal_func NormalTransform;
  46    GLvector4f normal;
  47 };
  48
  49 #define NORMAL_STAGE_DATA(stage) ((struct normal_stage_data *)stage->privatePtr)
  50
  51
  52
  53
  54 static GLboolean run_normal_stage( GLcontext *ctx,
  55                                    struct tnl_pipeline_stage *stage )
  56 {
  57    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
  58    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  59
  60    ASSERT(store->NormalTransform);
  61
  62    if (stage->changed_inputs) {
  63       /* We can only use the display list's saved normal lengths if we've
  64        * got a transformation matrix with uniform scaling.
  65        */
  66       const GLfloat *lengths;
  67       if (ctx->ModelviewMatrixStack.Top->flags & MAT_FLAG_GENERAL_SCALE)
  68          lengths = NULL;
  69       else
  70          lengths = VB->NormalLengthPtr;
  71
  72       store->NormalTransform( ctx->ModelviewMatrixStack.Top,
  73                               ctx->_ModelViewInvScale,
  74                               VB->NormalPtr,  /* input normals */
  75                               lengths,
  76                               &store->normal ); /* resulting normals */
  77    }
  78
  79    VB->NormalPtr = &store->normal;
  80    VB->NormalLengthPtr = 0;     /* no longer valid */
  81    return GL_TRUE;
  82 }
  83
  84
  85 static GLboolean run_validate_normal_stage( GLcontext *ctx,
  86                                             struct tnl_pipeline_stage *stage )
  87 {
  88    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
  89
  90
  91    if (ctx->_NeedEyeCoords) {
  92       GLuint transform = NORM_TRANSFORM_NO_ROT;
  93
  94       if (ctx->ModelviewMatrixStack.Top->flags & (MAT_FLAG_GENERAL |
  95                                   MAT_FLAG_ROTATION |
  96                                   MAT_FLAG_GENERAL_3D |
  97                                   MAT_FLAG_PERSPECTIVE))
  98          transform = NORM_TRANSFORM;
  99
 100
 101       if (ctx->Transform.Normalize) {
 102          store->NormalTransform = _mesa_normal_tab[transform | NORM_NORMALIZE];
 103       }
 104       else if (ctx->Transform.RescaleNormals &&
 105                ctx->_ModelViewInvScale != 1.0) {
 106          store->NormalTransform = _mesa_normal_tab[transform | NORM_RESCALE];
 107       }
 108       else {
 109          store->NormalTransform = _mesa_normal_tab[transform];
 110       }
 111    }
 112    else {
 113       if (ctx->Transform.Normalize) {
 114          store->NormalTransform = _mesa_normal_tab[NORM_NORMALIZE];
 115       }
 116       else if (!ctx->Transform.RescaleNormals &&
 117                ctx->_ModelViewInvScale != 1.0) {
 118          store->NormalTransform = _mesa_normal_tab[NORM_RESCALE];
 119       }
 120       else {
 121          store->NormalTransform = 0;
 122       }
 123    }
 124
 125    if (store->NormalTransform) {
 126       stage->run = run_normal_stage;
 127       return stage->run( ctx, stage );
 128    } else {
 129       stage->active = GL_FALSE; /* !!! */
 130       return GL_TRUE;
 131    }
 132 }
 133
 134
 135 static void check_normal_transform( GLcontext *ctx,
 136                                     struct tnl_pipeline_stage *stage )
 137 {
 138    stage->active = !ctx->VertexProgram.Enabled &&
 139       (ctx->Light.Enabled || (ctx->Texture._GenFlags & TEXGEN_NEED_NORMALS));
 140
 141    /* Don't clobber the initialize function:
 142     */
 143    if (stage->privatePtr)
 144       stage->run = run_validate_normal_stage;
 145 }
 146
 147
 148 static GLboolean alloc_normal_data( GLcontext *ctx,
 149                                  struct tnl_pipeline_stage *stage )
 150 {
 151    TNLcontext *tnl = TNL_CONTEXT(ctx);
 152    struct normal_stage_data *store;
 153    stage->privatePtr = MALLOC(sizeof(*store));
 154    store = NORMAL_STAGE_DATA(stage);
 155    if (!store)
 156       return GL_FALSE;
 157
 158    _mesa_vector4f_alloc( &store->normal, 0, tnl->vb.Size, 32 );
 159
 160    /* Now run the stage.
 161     */
 162    stage->run = run_validate_normal_stage;
 163    return stage->run( ctx, stage );
 164 }
 165
 166
 167
 168 static void free_normal_data( struct tnl_pipeline_stage *stage )
 169 {
 170    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
 171    if (store) {
 172       _mesa_vector4f_free( &store->normal );
 173       FREE( store );
 174       stage->privatePtr = NULL;
 175    }
 176 }
 177
 178 #define _TNL_NEW_NORMAL_TRANSFORM        (_NEW_MODELVIEW| \
 179                                           _NEW_TRANSFORM| \
 180                                           _MESA_NEW_NEED_NORMALS| \
 181                                           _MESA_NEW_NEED_EYE_COORDS)
 182
 183
 184
 185 const struct tnl_pipeline_stage _tnl_normal_transform_stage =
 186 {
 187    "normal transform",          /* name */
 188    _TNL_NEW_NORMAL_TRANSFORM,   /* re-check */
 189    _TNL_NEW_NORMAL_TRANSFORM,   /* re-run */
 190    GL_FALSE,                    /* active? */
 191    _TNL_BIT_NORMAL,             /* inputs */
 192    _TNL_BIT_NORMAL,             /* outputs */
 193    0,                           /* changed_inputs */
 194    NULL,                        /* private data */
 195    free_normal_data,            /* destructor */
 196    check_normal_transform,      /* check */
 197    alloc_normal_data            /* run -- initially set to alloc */
 198 };