src/mesa/tnl/t_vb_normals.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.1
   4  *
   5  * Copyright (C) 1999-2004  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  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Keith Whitwell <keith@tungstengraphics.com>
  26  */
  27
  28
  29 #include "glheader.h"
  30 #include "colormac.h"
  31 #include "context.h"
  32 #include "macros.h"
  33 #include "imports.h"
  34 #include "mtypes.h"
  35
  36 #include "math/m_xform.h"
  37
  38 #include "t_context.h"
  39 #include "t_pipeline.h"
  40
  41
  42
  43 struct normal_stage_data {
  44    normal_func NormalTransform;
  45    GLvector4f normal;
  46 };
  47
  48 #define NORMAL_STAGE_DATA(stage) ((struct normal_stage_data *)stage->privatePtr)
  49
  50
  51
  52
  53 static GLboolean run_normal_stage( GLcontext *ctx,
  54                                    struct tnl_pipeline_stage *stage )
  55 {
  56    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
  57    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  58
  59    ASSERT(store->NormalTransform);
  60
  61    if (stage->changed_inputs) {
  62       /* We can only use the display list's saved normal lengths if we've
  63        * got a transformation matrix with uniform scaling.
  64        */
  65       const GLfloat *lengths;
  66       if (ctx->ModelviewMatrixStack.Top->flags & MAT_FLAG_GENERAL_SCALE)
  67          lengths = NULL;
  68       else
  69          lengths = VB->NormalLengthPtr;
  70
  71       /* If there is only one normal, don't transform it multiple times:
  72        */
  73       if (VB->NormalPtr->stride == 0)
  74          VB->NormalPtr->count = 1;
  75
  76       store->NormalTransform( ctx->ModelviewMatrixStack.Top,
  77                               ctx->_ModelViewInvScale,
  78                               VB->NormalPtr,  /* input normals */
  79                               lengths,
  80                               &store->normal ); /* resulting normals */
  81
  82       if (VB->NormalPtr->stride == 0) {
  83          VB->NormalPtr->count = VB->Count;
  84          store->normal.stride = 0;
  85       }
  86       else
  87          store->normal.stride = 16;
  88    }
  89
  90    VB->NormalPtr = &store->normal;
  91    VB->AttribPtr[_TNL_ATTRIB_NORMAL] = VB->NormalPtr;
  92
  93    VB->NormalLengthPtr = 0;     /* no longer valid */
  94    return GL_TRUE;
  95 }
  96
  97
  98 static GLboolean run_validate_normal_stage( GLcontext *ctx,
  99                                             struct tnl_pipeline_stage *stage )
 100 {
 101    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
 102
 103
 104    if (ctx->_NeedEyeCoords) {
 105       GLuint transform = NORM_TRANSFORM_NO_ROT;
 106
 107       if (ctx->ModelviewMatrixStack.Top->flags & (MAT_FLAG_GENERAL |
 108                                   MAT_FLAG_ROTATION |
 109                                   MAT_FLAG_GENERAL_3D |
 110                                   MAT_FLAG_PERSPECTIVE))
 111          transform = NORM_TRANSFORM;
 112
 113
 114       if (ctx->Transform.Normalize) {
 115          store->NormalTransform = _mesa_normal_tab[transform | NORM_NORMALIZE];
 116       }
 117       else if (ctx->Transform.RescaleNormals &&
 118                ctx->_ModelViewInvScale != 1.0) {
 119          store->NormalTransform = _mesa_normal_tab[transform | NORM_RESCALE];
 120       }
 121       else {
 122          store->NormalTransform = _mesa_normal_tab[transform];
 123       }
 124    }
 125    else {
 126       if (ctx->Transform.Normalize) {
 127          store->NormalTransform = _mesa_normal_tab[NORM_NORMALIZE];
 128       }
 129       else if (!ctx->Transform.RescaleNormals &&
 130                ctx->_ModelViewInvScale != 1.0) {
 131          store->NormalTransform = _mesa_normal_tab[NORM_RESCALE];
 132       }
 133       else {
 134          store->NormalTransform = 0;
 135       }
 136    }
 137
 138    if (store->NormalTransform) {
 139       stage->run = run_normal_stage;
 140       return stage->run( ctx, stage );
 141    } else {
 142       stage->active = GL_FALSE; /* !!! */
 143       return GL_TRUE;
 144    }
 145 }
 146
 147
 148 static void check_normal_transform( GLcontext *ctx,
 149                                     struct tnl_pipeline_stage *stage )
 150 {
 151    stage->active = !ctx->VertexProgram._Enabled &&
 152       (ctx->Light.Enabled || (ctx->Texture._GenFlags & TEXGEN_NEED_NORMALS));
 153
 154    /* Don't clobber the initialize function:
 155     */
 156    if (stage->privatePtr)
 157       stage->run = run_validate_normal_stage;
 158 }
 159
 160
 161 static GLboolean alloc_normal_data( GLcontext *ctx,
 162                                  struct tnl_pipeline_stage *stage )
 163 {
 164    TNLcontext *tnl = TNL_CONTEXT(ctx);
 165    struct normal_stage_data *store;
 166    stage->privatePtr = MALLOC(sizeof(*store));
 167    store = NORMAL_STAGE_DATA(stage);
 168    if (!store)
 169       return GL_FALSE;
 170
 171    _mesa_vector4f_alloc( &store->normal, 0, tnl->vb.Size, 32 );
 172
 173    /* Now run the stage.
 174     */
 175    stage->run = run_validate_normal_stage;
 176    return stage->run( ctx, stage );
 177 }
 178
 179
 180
 181 static void free_normal_data( struct tnl_pipeline_stage *stage )
 182 {
 183    struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
 184    if (store) {
 185       _mesa_vector4f_free( &store->normal );
 186       FREE( store );
 187       stage->privatePtr = NULL;
 188    }
 189 }
 190
 191 #define _TNL_NEW_NORMAL_TRANSFORM        (_NEW_MODELVIEW| \
 192                                           _NEW_TRANSFORM| \
 193                                           _NEW_PROGRAM| \
 194                                           _MESA_NEW_NEED_NORMALS| \
 195                                           _MESA_NEW_NEED_EYE_COORDS)
 196
 197
 198
 199 const struct tnl_pipeline_stage _tnl_normal_transform_stage =
 200 {
 201    "normal transform",          /* name */
 202    _TNL_NEW_NORMAL_TRANSFORM,   /* re-check */
 203    _TNL_NEW_NORMAL_TRANSFORM,   /* re-run */
 204    GL_FALSE,                    /* active? */
 205    _TNL_BIT_NORMAL,             /* inputs */
 206    _TNL_BIT_NORMAL,             /* outputs */
 207    0,                           /* changed_inputs */
 208    NULL,                        /* private data */
 209    free_normal_data,            /* destructor */
 210    check_normal_transform,      /* check */
 211    alloc_normal_data            /* run -- initially set to alloc */
 212 };