src/mesa/tnl/t_vb_vertex.c

   1 /* $Id: t_vb_vertex.c,v 1.12 2002/01/22 14:35:17 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   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 <keithw@valinux.com>
  28  */
  29
  30
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "macros.h"
  35 #include "mem.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.ClipEnabled[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    if (stage->changed_inputs) {
 141
 142       if (ctx->_NeedEyeCoords) {
 143          /* Separate modelview and project transformations:
 144           */
 145          if (ctx->ModelviewMatrixStack.Top->type == MATRIX_IDENTITY)
 146             VB->EyePtr = VB->ObjPtr;
 147          else
 148             VB->EyePtr = TransformRaw( &store->eye,
 149                                        ctx->ModelviewMatrixStack.Top,
 150                                        VB->ObjPtr);
 151
 152          if (ctx->ProjectionMatrixStack.Top->type == MATRIX_IDENTITY)
 153             VB->ClipPtr = VB->EyePtr;
 154          else
 155             VB->ClipPtr = TransformRaw( &store->clip,
 156                                         ctx->ProjectionMatrixStack.Top,
 157                                         VB->EyePtr );
 158       }
 159       else {
 160          /* Combined modelviewproject transform:
 161           */
 162          if (ctx->_ModelProjectMatrix.type == MATRIX_IDENTITY)
 163             VB->ClipPtr = VB->ObjPtr;
 164          else
 165             VB->ClipPtr = TransformRaw( &store->clip,
 166                                         &ctx->_ModelProjectMatrix,
 167                                         VB->ObjPtr );
 168       }
 169
 170       /* Drivers expect this to be clean to element 4...
 171        */
 172       if (VB->ClipPtr->size < 4) {
 173          if (VB->ClipPtr->flags & VEC_NOT_WRITEABLE) {
 174             ASSERT(VB->ClipPtr == VB->ObjPtr);
 175             VB->import_data( ctx, VERT_BIT_POS, VEC_NOT_WRITEABLE );
 176             VB->ClipPtr = VB->ObjPtr;
 177          }
 178          if (VB->ClipPtr->size == 2)
 179             _mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 2 );
 180          _mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 3 );
 181       }
 182
 183       /* Cliptest and perspective divide.  Clip functions must clear
 184        * the clipmask.
 185        */
 186       store->ormask = 0;
 187       store->andmask = CLIP_ALL_BITS;
 188
 189       if (tnl->NeedNdcCoords) {
 190          VB->NdcPtr =
 191             _mesa_clip_tab[VB->ClipPtr->size]( VB->ClipPtr,
 192                                                &store->proj,
 193                                                store->clipmask,
 194                                                &store->ormask,
 195                                                &store->andmask );
 196
 197       }
 198       else {
 199          VB->NdcPtr = 0;
 200          _mesa_clip_np_tab[VB->ClipPtr->size]( VB->ClipPtr,
 201                                                0,
 202                                                store->clipmask,
 203                                                &store->ormask,
 204                                                &store->andmask );
 205       }
 206
 207       if (store->andmask)
 208          return GL_FALSE;
 209
 210
 211       /* Test userclip planes.  This contributes to VB->ClipMask, so
 212        * is essentially required to be in this stage.
 213        */
 214       if (ctx->Transform._AnyClip) {
 215          usercliptab[VB->ClipPtr->size]( ctx,
 216                                          VB->ClipPtr,
 217                                          store->clipmask,
 218                                          &store->ormask,
 219                                          &store->andmask );
 220
 221          if (store->andmask)
 222             return GL_FALSE;
 223       }
 224
 225       VB->ClipOrMask = store->ormask;
 226       VB->ClipMask = store->clipmask;
 227
 228       if (VB->ClipPtr == VB->ObjPtr && (VB->importable_data & VERT_BIT_POS))
 229          VB->importable_data |= VERT_BIT_CLIP;
 230
 231       store->save_eyeptr = VB->EyePtr;
 232       store->save_clipptr = VB->ClipPtr;
 233       store->save_ndcptr = VB->NdcPtr;
 234    }
 235    else {
 236       /* Replay the sideeffects.
 237        */
 238       VB->EyePtr = store->save_eyeptr;
 239       VB->ClipPtr = store->save_clipptr;
 240       VB->NdcPtr = store->save_ndcptr;
 241       VB->ClipMask = store->clipmask;
 242       VB->ClipOrMask = store->ormask;
 243       if (VB->ClipPtr == VB->ObjPtr && (VB->importable_data & VERT_BIT_POS))
 244          VB->importable_data |= VERT_BIT_CLIP;
 245       if (store->andmask)
 246          return GL_FALSE;
 247    }
 248
 249    return GL_TRUE;
 250 }
 251
 252
 253 static void check_vertex( GLcontext *ctx, struct gl_pipeline_stage *stage )
 254 {
 255    stage->active = !ctx->VertexProgram.Enabled;
 256 }
 257
 258 static GLboolean init_vertex_stage( GLcontext *ctx,
 259                                     struct gl_pipeline_stage *stage )
 260 {
 261    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
 262    struct vertex_stage_data *store;
 263    GLuint size = VB->Size;
 264
 265    stage->privatePtr = CALLOC(sizeof(*store));
 266    store = VERTEX_STAGE_DATA(stage);
 267    if (!store)
 268       return GL_FALSE;
 269
 270    _mesa_vector4f_alloc( &store->eye, 0, size, 32 );
 271    _mesa_vector4f_alloc( &store->clip, 0, size, 32 );
 272    _mesa_vector4f_alloc( &store->proj, 0, size, 32 );
 273
 274    store->clipmask = (GLubyte *) ALIGN_MALLOC(sizeof(GLubyte)*size, 32 );
 275
 276    if (!store->clipmask ||
 277        !store->eye.data ||
 278        !store->clip.data ||
 279        !store->proj.data)
 280       return GL_FALSE;
 281
 282    /* Now run the stage.
 283     */
 284    stage->run = run_vertex_stage;
 285    return stage->run( ctx, stage );
 286 }
 287
 288 static void dtr( struct gl_pipeline_stage *stage )
 289 {
 290    struct vertex_stage_data *store = VERTEX_STAGE_DATA(stage);
 291
 292    if (store) {
 293       _mesa_vector4f_free( &store->eye );
 294       _mesa_vector4f_free( &store->clip );
 295       _mesa_vector4f_free( &store->proj );
 296       ALIGN_FREE( store->clipmask );
 297       FREE(store);
 298       stage->privatePtr = NULL;
 299       stage->run = init_vertex_stage;
 300    }
 301 }
 302
 303
 304 const struct gl_pipeline_stage _tnl_vertex_transform_stage =
 305 {
 306    "modelview/project/cliptest/divide",
 307    0,                           /* re-check -- always on */
 308    _MESA_NEW_NEED_EYE_COORDS |
 309    _NEW_MODELVIEW|
 310    _NEW_PROJECTION|
 311    _NEW_TRANSFORM,              /* re-run */
 312    GL_TRUE,                     /* active */
 313    VERT_BIT_POS,                /* inputs */
 314    VERT_BIT_EYE|VERT_BIT_CLIP,          /* outputs */
 315    0,                           /* changed_inputs */
 316    NULL,                        /* private data */
 317    dtr,                         /* destructor */
 318    check_vertex,                /* check */
 319    init_vertex_stage            /* run -- initially set to init */
 320 };