src/mesa/tnl/t_vb_vertex.c

   1 /* $Id: t_vb_vertex.c,v 1.17 2002/10/31 17:14:37 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  5.0
   6  *
   7  * Copyright (C) 1999-2001  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 <keith@tungstengraphics.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 vertex_stage_data {
  47    GLvector4f eye;
  48    GLvector4f clip;
  49    GLvector4f proj;
  50    GLubyte *clipmask;
  51    GLubyte ormask;
  52    GLubyte andmask;
  53
  54
  55    /* Need these because it's difficult to replay the sideeffects
  56     * analytically.
  57     */
  58    GLvector4f *save_eyeptr;
  59    GLvector4f *save_clipptr;
  60    GLvector4f *save_ndcptr;
  61 };
  62
  63 #define VERTEX_STAGE_DATA(stage) ((struct vertex_stage_data *)stage->privatePtr)
  64
  65
  66
  67
  68 /* This function implements cliptesting for user-defined clip planes.
  69  * The clipping of primitives to these planes is implemented in
  70  * t_render_clip.h.
  71  */
  72 #define USER_CLIPTEST(NAME, SZ)                                 \
  73 static void NAME( GLcontext *ctx,                               \
  74                   GLvector4f *clip,                             \
  75                   GLubyte *clipmask,                            \
  76                   GLubyte *clipormask,                          \
  77                   GLubyte *clipandmask )                        \
  78 {                                                               \
  79    GLuint p;                                                    \
  80                                                                 \
  81    for (p = 0; p < ctx->Const.MaxClipPlanes; p++)               \
  82       if (ctx->Transform.ClipPlanesEnabled & (1 << p)) {        \
  83          GLuint nr, i;                                          \
  84          const GLfloat a = ctx->Transform._ClipUserPlane[p][0]; \
  85          const GLfloat b = ctx->Transform._ClipUserPlane[p][1]; \
  86          const GLfloat c = ctx->Transform._ClipUserPlane[p][2]; \
  87          const GLfloat d = ctx->Transform._ClipUserPlane[p][3]; \
  88          GLfloat *coord = (GLfloat *)clip->data;                \
  89          GLuint stride = clip->stride;                          \
  90          GLuint count = clip->count;                            \
  91                                                                 \
  92          for (nr = 0, i = 0 ; i < count ; i++) {                \
  93             GLfloat dp = coord[0] * a + coord[1] * b;           \
  94             if (SZ > 2) dp += coord[2] * c;                     \
  95             if (SZ > 3) dp += coord[3] * d; else dp += d;       \
  96                                                                 \
  97             if (dp < 0) {                                       \
  98                nr++;                                            \
  99                clipmask[i] |= CLIP_USER_BIT;                    \
 100             }                                                   \
 101                                                                 \
 102             STRIDE_F(coord, stride);                            \
 103          }                                                      \
 104                                                                 \
 105          if (nr > 0) {                                          \
 106             *clipormask |= CLIP_USER_BIT;                       \
 107             if (nr == count) {                                  \
 108                *clipandmask |= CLIP_USER_BIT;                   \
 109                return;                                          \
 110             }                                                   \
 111          }                                                      \
 112       }                                                         \
 113 }
 114
 115
 116 USER_CLIPTEST(userclip2, 2)
 117 USER_CLIPTEST(userclip3, 3)
 118 USER_CLIPTEST(userclip4, 4)
 119
 120 static void (*(usercliptab[5]))( GLcontext *,
 121                                  GLvector4f *, GLubyte *,
 122                                  GLubyte *, GLubyte * ) =
 123 {
 124    0,
 125    0,
 126    userclip2,
 127    userclip3,
 128    userclip4
 129 };
 130
 131
 132
 133 static GLboolean run_vertex_stage( GLcontext *ctx,
 134                                    struct gl_pipeline_stage *stage )
 135 {
 136    struct vertex_stage_data *store = (struct vertex_stage_data *)stage->privatePtr;
 137    TNLcontext *tnl = TNL_CONTEXT(ctx);
 138    struct vertex_buffer *VB = &tnl->vb;
 139
 140    ASSERT(!ctx->VertexProgram.Enabled);
 141
 142    if (stage->changed_inputs) {
 143
 144       if (ctx->_NeedEyeCoords) {
 145          /* Separate modelview transformation:
 146           * Use combined ModelProject to avoid some depth artifacts
 147           */
 148          if (ctx->ModelviewMatrixStack.Top->type == MATRIX_IDENTITY)
 149             VB->EyePtr = VB->ObjPtr;
 150          else
 151             VB->EyePtr = TransformRaw( &store->eye,
 152                                        ctx->ModelviewMatrixStack.Top,
 153                                        VB->ObjPtr);
 154
 155          if (ctx->ProjectionMatrixStack.Top->type == MATRIX_IDENTITY)
 156             VB->ClipPtr = VB->EyePtr;
 157          else
 158             VB->ClipPtr = TransformRaw( &store->clip,
 159                                         &ctx->_ModelProjectMatrix,
 160                                         VB->ObjPtr );
 161       }
 162       else {
 163          /* Combined modelviewproject transform:
 164           */
 165          if (ctx->_ModelProjectMatrix.type == MATRIX_IDENTITY)
 166             VB->ClipPtr = VB->ObjPtr;
 167          else
 168             VB->ClipPtr = TransformRaw( &store->clip,
 169                                         &ctx->_ModelProjectMatrix,
 170                                         VB->ObjPtr );
 171       }
 172
 173       /* Drivers expect this to be clean to element 4...
 174        */
 175       if (VB->ClipPtr->size < 4) {
 176          if (VB->ClipPtr->flags & VEC_NOT_WRITEABLE) {
 177             ASSERT(VB->ClipPtr == VB->ObjPtr);
 178             VB->import_data( ctx, VERT_BIT_POS, VEC_NOT_WRITEABLE );
 179             VB->ClipPtr = VB->ObjPtr;
 180          }
 181          if (VB->ClipPtr->size == 2)
 182             _mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 2 );
 183          _mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 3 );
 184       }
 185
 186       /* Cliptest and perspective divide.  Clip functions must clear
 187        * the clipmask.
 188        */
 189       store->ormask = 0;
 190       store->andmask = CLIP_ALL_BITS;
 191
 192       if (tnl->NeedNdcCoords) {
 193          VB->NdcPtr =
 194             _mesa_clip_tab[VB->ClipPtr->size]( VB->ClipPtr,
 195                                                &store->proj,
 196                                                store->clipmask,
 197                                                &store->ormask,
 198                                                &store->andmask );
 199       }
 200       else {
 201          VB->NdcPtr = 0;
 202          _mesa_clip_np_tab[VB->ClipPtr->size]( VB->ClipPtr,
 203                                                0,
 204                                                store->clipmask,
 205                                                &store->ormask,
 206                                                &store->andmask );
 207       }
 208
 209       if (store->andmask)
 210          return GL_FALSE;
 211
 212
 213       /* Test userclip planes.  This contributes to VB->ClipMask, so
 214        * is essentially required to be in this stage.
 215        */
 216       if (ctx->Transform.ClipPlanesEnabled) {
 217          usercliptab[VB->ClipPtr->size]( ctx,
 218                                          VB->ClipPtr,
 219                                          store->clipmask,
 220                                          &store->ormask,
 221                                          &store->andmask );
 222
 223          if (store->andmask)
 224             return GL_FALSE;
 225       }
 226
 227       VB->ClipOrMask = store->ormask;
 228       VB->ClipMask = store->clipmask;
 229
 230       if (VB->ClipPtr == VB->ObjPtr && (VB->importable_data & VERT_BIT_POS))
 231          VB->importable_data |= VERT_BIT_CLIP;
 232
 233       store->save_eyeptr = VB->EyePtr;
 234       store->save_clipptr = VB->ClipPtr;
 235       store->save_ndcptr = VB->NdcPtr;
 236    }
 237    else {
 238       /* Replay the sideeffects.
 239        */
 240       VB->EyePtr = store->save_eyeptr;
 241       VB->ClipPtr = store->save_clipptr;
 242       VB->NdcPtr = store->save_ndcptr;
 243       VB->ClipMask = store->clipmask;
 244       VB->ClipOrMask = store->ormask;
 245       if (VB->ClipPtr == VB->ObjPtr && (VB->importable_data & VERT_BIT_POS))
 246          VB->importable_data |= VERT_BIT_CLIP;
 247       if (store->andmask)
 248          return GL_FALSE;
 249    }
 250
 251    return GL_TRUE;
 252 }
 253
 254
 255 static void check_vertex( GLcontext *ctx, struct gl_pipeline_stage *stage )
 256 {
 257    stage->active = !ctx->VertexProgram.Enabled;
 258 }
 259
 260 static GLboolean init_vertex_stage( GLcontext *ctx,
 261                                     struct gl_pipeline_stage *stage )
 262 {
 263    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
 264    struct vertex_stage_data *store;
 265    GLuint size = VB->Size;
 266
 267    stage->privatePtr = CALLOC(sizeof(*store));
 268    store = VERTEX_STAGE_DATA(stage);
 269    if (!store)
 270       return GL_FALSE;
 271
 272    _mesa_vector4f_alloc( &store->eye, 0, size, 32 );
 273    _mesa_vector4f_alloc( &store->clip, 0, size, 32 );
 274    _mesa_vector4f_alloc( &store->proj, 0, size, 32 );
 275
 276    store->clipmask = (GLubyte *) ALIGN_MALLOC(sizeof(GLubyte)*size, 32 );
 277
 278    if (!store->clipmask ||
 279        !store->eye.data ||
 280        !store->clip.data ||
 281        !store->proj.data)
 282       return GL_FALSE;
 283
 284    /* Now run the stage.
 285     */
 286    stage->run = run_vertex_stage;
 287    return stage->run( ctx, stage );
 288 }
 289
 290 static void dtr( struct gl_pipeline_stage *stage )
 291 {
 292    struct vertex_stage_data *store = VERTEX_STAGE_DATA(stage);
 293
 294    if (store) {
 295       _mesa_vector4f_free( &store->eye );
 296       _mesa_vector4f_free( &store->clip );
 297       _mesa_vector4f_free( &store->proj );
 298       ALIGN_FREE( store->clipmask );
 299       FREE(store);
 300       stage->privatePtr = NULL;
 301       stage->run = init_vertex_stage;
 302    }
 303 }
 304
 305
 306 const struct gl_pipeline_stage _tnl_vertex_transform_stage =
 307 {
 308    "modelview/project/cliptest/divide",
 309    _NEW_PROGRAM,                /* check_state: only care about vertex prog */
 310    _MESA_NEW_NEED_EYE_COORDS |  /* run_state: when to invalidate / re-run */
 311    _NEW_MODELVIEW|
 312    _NEW_PROJECTION|
 313    _NEW_PROGRAM|
 314    _NEW_TRANSFORM,
 315    GL_TRUE,                     /* active */
 316    VERT_BIT_POS,                /* inputs */
 317    VERT_BIT_EYE|VERT_BIT_CLIP,          /* outputs */
 318    0,                           /* changed_inputs */
 319    NULL,                        /* private data */
 320    dtr,                         /* destructor */
 321    check_vertex,                /* check */
 322    init_vertex_stage            /* run -- initially set to init */
 323 };