src/mesa/main/state.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 /**
  27  * \file state.c
  28  * State management.
  29  *
  30  * This file manages recalculation of derived values in struct gl_context.
  31  */
  32
  33
  34 #include "glheader.h"
  35 #include "mtypes.h"
  36 #include "arrayobj.h"
  37 #include "context.h"
  38 #include "debug.h"
  39 #include "macros.h"
  40 #include "ffvertex_prog.h"
  41 #include "framebuffer.h"
  42 #include "light.h"
  43 #include "matrix.h"
  44 #include "pixel.h"
  45 #include "program/program.h"
  46 #include "program/prog_parameter.h"
  47 #include "shaderobj.h"
  48 #include "state.h"
  49 #include "stencil.h"
  50 #include "texenvprogram.h"
  51 #include "texobj.h"
  52 #include "texstate.h"
  53 #include "varray.h"
  54 #include "viewport.h"
  55 #include "blend.h"
  56
  57
  58 /**
  59  * Update the following fields:
  60  *   ctx->VertexProgram._Enabled
  61  *   ctx->FragmentProgram._Enabled
  62  *   ctx->ATIFragmentShader._Enabled
  63  * This needs to be done before texture state validation.
  64  */
  65 static void
  66 update_program_enables(struct gl_context *ctx)
  67 {
  68    /* These _Enabled flags indicate if the user-defined ARB/NV vertex/fragment
  69     * program is enabled AND valid.  Similarly for ATI fragment shaders.
  70     * GLSL shaders not relevant here.
  71     */
  72    ctx->VertexProgram._Enabled = ctx->VertexProgram.Enabled
  73       && ctx->VertexProgram.Current->arb.Instructions;
  74    ctx->FragmentProgram._Enabled = ctx->FragmentProgram.Enabled
  75       && ctx->FragmentProgram.Current->arb.Instructions;
  76    ctx->ATIFragmentShader._Enabled = ctx->ATIFragmentShader.Enabled
  77       && ctx->ATIFragmentShader.Current->Instructions[0];
  78 }
  79
  80
  81 /**
  82  * Update the ctx->*Program._Current pointers to point to the
  83  * current/active programs.  Then call ctx->Driver.BindProgram() to
  84  * tell the driver which programs to use.
  85  *
  86  * Programs may come from 3 sources: GLSL shaders, ARB/NV_vertex/fragment
  87  * programs or programs derived from fixed-function state.
  88  *
  89  * This function needs to be called after texture state validation in case
  90  * we're generating a fragment program from fixed-function texture state.
  91  *
  92  * \return bitfield which will indicate _NEW_PROGRAM state if a new vertex
  93  * or fragment program is being used.
  94  */
  95 static GLbitfield
  96 update_program(struct gl_context *ctx)
  97 {
  98    struct gl_program *vsProg =
  99       ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
 100    struct gl_program *tcsProg =
 101       ctx->_Shader->CurrentProgram[MESA_SHADER_TESS_CTRL];
 102    struct gl_program *tesProg =
 103       ctx->_Shader->CurrentProgram[MESA_SHADER_TESS_EVAL];
 104    struct gl_program *gsProg =
 105       ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
 106    struct gl_program *fsProg =
 107       ctx->_Shader->CurrentProgram[MESA_SHADER_FRAGMENT];
 108    struct gl_program *csProg =
 109       ctx->_Shader->CurrentProgram[MESA_SHADER_COMPUTE];
 110    const struct gl_program *prevVP = ctx->VertexProgram._Current;
 111    const struct gl_program *prevFP = ctx->FragmentProgram._Current;
 112    const struct gl_program *prevGP = ctx->GeometryProgram._Current;
 113    const struct gl_program *prevTCP = ctx->TessCtrlProgram._Current;
 114    const struct gl_program *prevTEP = ctx->TessEvalProgram._Current;
 115    const struct gl_program *prevCP = ctx->ComputeProgram._Current;
 116    GLbitfield new_state = 0x0;
 117
 118    /*
 119     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 120     * pointers to the programs that should be used for rendering.  If either
 121     * is NULL, use fixed-function code paths.
 122     *
 123     * These programs may come from several sources.  The priority is as
 124     * follows:
 125     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 126     *   2. ARB/NV vertex/fragment programs
 127     *   3. ATI fragment shader
 128     *   4. Programs derived from fixed-function state.
 129     *
 130     * Note: it's possible for a vertex shader to get used with a fragment
 131     * program (and vice versa) here, but in practice that shouldn't ever
 132     * come up, or matter.
 133     */
 134
 135    if (fsProg) {
 136       /* Use GLSL fragment shader */
 137       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 138                               fsProg);
 139       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, fsProg);
 140       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 141                               NULL);
 142    }
 143    else if (ctx->FragmentProgram._Enabled) {
 144       /* Use user-defined fragment program */
 145       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 146                               NULL);
 147       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 148                               ctx->FragmentProgram.Current);
 149       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 150                               NULL);
 151    }
 152    else if (ctx->ATIFragmentShader._Enabled &&
 153             ctx->ATIFragmentShader.Current->Program) {
 154        /* Use the enabled ATI fragment shader's associated program */
 155       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 156                               NULL);
 157       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 158                               ctx->ATIFragmentShader.Current->Program);
 159       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 160                               NULL);
 161    }
 162    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 163       /* Use fragment program generated from fixed-function state */
 164       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 165
 166       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 167                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 168       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 169                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 170       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 171                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 172    }
 173    else {
 174       /* No fragment program */
 175       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, NULL);
 176       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 177                               NULL);
 178    }
 179
 180    if (gsProg) {
 181       /* Use GLSL geometry shader */
 182       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, gsProg);
 183    } else {
 184       /* No geometry program */
 185       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, NULL);
 186    }
 187
 188    if (tesProg) {
 189       /* Use GLSL tessellation evaluation shader */
 190       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, tesProg);
 191    }
 192    else {
 193       /* No tessellation evaluation program */
 194       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, NULL);
 195    }
 196
 197    if (tcsProg) {
 198       /* Use GLSL tessellation control shader */
 199       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, tcsProg);
 200    }
 201    else {
 202       /* No tessellation control program */
 203       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, NULL);
 204    }
 205
 206    /* Examine vertex program after fragment program as
 207     * _mesa_get_fixed_func_vertex_program() needs to know active
 208     * fragprog inputs.
 209     */
 210    if (vsProg) {
 211       /* Use GLSL vertex shader */
 212       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, vsProg);
 213    }
 214    else if (ctx->VertexProgram._Enabled) {
 215       /* Use user-defined vertex program */
 216       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 217                               ctx->VertexProgram.Current);
 218    }
 219    else if (ctx->VertexProgram._MaintainTnlProgram) {
 220       /* Use vertex program generated from fixed-function state */
 221       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 222                               _mesa_get_fixed_func_vertex_program(ctx));
 223       _mesa_reference_program(ctx, &ctx->VertexProgram._TnlProgram,
 224                               ctx->VertexProgram._Current);
 225    }
 226    else {
 227       /* no vertex program */
 228       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, NULL);
 229    }
 230
 231    if (csProg) {
 232       /* Use GLSL compute shader */
 233       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, csProg);
 234    } else {
 235       /* no compute program */
 236       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, NULL);
 237    }
 238
 239    /* Let the driver know what's happening:
 240     */
 241    if (ctx->FragmentProgram._Current != prevFP) {
 242       new_state |= _NEW_PROGRAM;
 243       if (ctx->Driver.BindProgram) {
 244          ctx->Driver.BindProgram(ctx, GL_FRAGMENT_PROGRAM_ARB,
 245                                  ctx->FragmentProgram._Current);
 246       }
 247    }
 248
 249    if (ctx->GeometryProgram._Current != prevGP) {
 250       new_state |= _NEW_PROGRAM;
 251       if (ctx->Driver.BindProgram) {
 252          ctx->Driver.BindProgram(ctx, GL_GEOMETRY_PROGRAM_NV,
 253                                  ctx->GeometryProgram._Current);
 254       }
 255    }
 256
 257    if (ctx->TessEvalProgram._Current != prevTEP) {
 258       new_state |= _NEW_PROGRAM;
 259       if (ctx->Driver.BindProgram) {
 260          ctx->Driver.BindProgram(ctx, GL_TESS_EVALUATION_PROGRAM_NV,
 261                                  ctx->TessEvalProgram._Current);
 262       }
 263    }
 264
 265    if (ctx->TessCtrlProgram._Current != prevTCP) {
 266       new_state |= _NEW_PROGRAM;
 267       if (ctx->Driver.BindProgram) {
 268          ctx->Driver.BindProgram(ctx, GL_TESS_CONTROL_PROGRAM_NV,
 269                                  ctx->TessCtrlProgram._Current);
 270       }
 271    }
 272
 273    if (ctx->VertexProgram._Current != prevVP) {
 274       new_state |= _NEW_PROGRAM;
 275       if (ctx->Driver.BindProgram) {
 276          ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
 277                                  ctx->VertexProgram._Current);
 278       }
 279    }
 280
 281    if (ctx->ComputeProgram._Current != prevCP) {
 282       new_state |= _NEW_PROGRAM;
 283       if (ctx->Driver.BindProgram) {
 284          ctx->Driver.BindProgram(ctx, GL_COMPUTE_PROGRAM_NV,
 285                                  ctx->ComputeProgram._Current);
 286       }
 287    }
 288
 289    return new_state;
 290 }
 291
 292
 293 /**
 294  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 295  */
 296 static GLbitfield
 297 update_program_constants(struct gl_context *ctx)
 298 {
 299    GLbitfield new_state = 0x0;
 300
 301    if (ctx->FragmentProgram._Current) {
 302       const struct gl_program_parameter_list *params =
 303          ctx->FragmentProgram._Current->Parameters;
 304       if (params && params->StateFlags & ctx->NewState) {
 305          new_state |= _NEW_PROGRAM_CONSTANTS;
 306       }
 307    }
 308
 309    /* Don't handle tessellation and geometry shaders here. They don't use
 310     * any state constants.
 311     */
 312
 313    if (ctx->VertexProgram._Current) {
 314       const struct gl_program_parameter_list *params =
 315          ctx->VertexProgram._Current->Parameters;
 316       if (params && params->StateFlags & ctx->NewState) {
 317          new_state |= _NEW_PROGRAM_CONSTANTS;
 318       }
 319    }
 320
 321    return new_state;
 322 }
 323
 324
 325
 326
 327 /**
 328  * Update the ctx->Polygon._FrontBit flag.
 329  */
 330 static void
 331 update_frontbit(struct gl_context *ctx)
 332 {
 333    if (ctx->Transform.ClipOrigin == GL_LOWER_LEFT)
 334       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CW);
 335    else
 336       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CCW);
 337 }
 338
 339
 340 /**
 341  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 342  */
 343 static void
 344 update_twoside(struct gl_context *ctx)
 345 {
 346    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX] ||
 347        ctx->VertexProgram._Enabled) {
 348       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 349    } else {
 350       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 351                                             ctx->Light.Model.TwoSide);
 352    }
 353 }
 354
 355
 356 /**
 357  * Compute derived GL state.
 358  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 359  * be called before rendering anything.
 360  *
 361  * Calls dd_function_table::UpdateState to perform any internal state
 362  * management necessary.
 363  *
 364  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 365  * _mesa_update_buffer_bounds(),
 366  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 367  */
 368 void
 369 _mesa_update_state_locked( struct gl_context *ctx )
 370 {
 371    GLbitfield new_state = ctx->NewState;
 372    GLbitfield prog_flags = _NEW_PROGRAM;
 373    GLbitfield new_prog_state = 0x0;
 374    const GLbitfield computed_states = ~(_NEW_CURRENT_ATTRIB | _NEW_LINE);
 375
 376    /* we can skip a bunch of state validation checks if the dirty
 377     * state matches one or more bits in 'computed_states'.
 378     */
 379    if ((new_state & computed_states) == 0)
 380       goto out;
 381
 382    if (MESA_VERBOSE & VERBOSE_STATE)
 383       _mesa_print_state("_mesa_update_state", new_state);
 384
 385    /* Determine which state flags effect vertex/fragment program state */
 386    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 387       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 388                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 389                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 390                      _NEW_COLOR);
 391    }
 392    if (ctx->VertexProgram._MaintainTnlProgram) {
 393       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 394                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 395                      _NEW_FOG | _NEW_LIGHT |
 396                      _MESA_NEW_NEED_EYE_COORDS);
 397    }
 398
 399    /*
 400     * Now update derived state info
 401     */
 402
 403    if (new_state & prog_flags)
 404       update_program_enables( ctx );
 405
 406    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 407       _mesa_update_modelview_project( ctx, new_state );
 408
 409    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 410       _mesa_update_texture( ctx, new_state );
 411
 412    if (new_state & _NEW_POLYGON)
 413       update_frontbit( ctx );
 414
 415    if (new_state & _NEW_BUFFERS)
 416       _mesa_update_framebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer);
 417
 418    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 419       _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
 420
 421    if (new_state & _NEW_LIGHT)
 422       _mesa_update_lighting( ctx );
 423
 424    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 425       update_twoside( ctx );
 426
 427    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 428       _mesa_update_stencil( ctx );
 429
 430    if (new_state & _NEW_PIXEL)
 431       _mesa_update_pixel( ctx, new_state );
 432
 433    /* ctx->_NeedEyeCoords is now up to date.
 434     *
 435     * If the truth value of this variable has changed, update for the
 436     * new lighting space and recompute the positions of lights and the
 437     * normal transform.
 438     *
 439     * If the lighting space hasn't changed, may still need to recompute
 440     * light positions & normal transforms for other reasons.
 441     */
 442    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 443       _mesa_update_tnl_spaces( ctx, new_state );
 444
 445    if (new_state & prog_flags) {
 446       /* When we generate programs from fixed-function vertex/fragment state
 447        * this call may generate/bind a new program.  If so, we need to
 448        * propogate the _NEW_PROGRAM flag to the driver.
 449        */
 450       new_prog_state |= update_program( ctx );
 451    }
 452
 453    if (new_state & _NEW_ARRAY)
 454       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 455
 456  out:
 457    new_prog_state |= update_program_constants(ctx);
 458
 459    /*
 460     * Give the driver a chance to act upon the new_state flags.
 461     * The driver might plug in different span functions, for example.
 462     * Also, this is where the driver can invalidate the state of any
 463     * active modules (such as swrast_setup, swrast, tnl, etc).
 464     *
 465     * Set ctx->NewState to zero to avoid recursion if
 466     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 467     */
 468    new_state = ctx->NewState | new_prog_state;
 469    ctx->NewState = 0;
 470    ctx->Driver.UpdateState(ctx, new_state);
 471    ctx->Array.VAO->NewArrays = 0x0;
 472 }
 473
 474
 475 /* This is the usual entrypoint for state updates:
 476  */
 477 void
 478 _mesa_update_state( struct gl_context *ctx )
 479 {
 480    _mesa_lock_context_textures(ctx);
 481    _mesa_update_state_locked(ctx);
 482    _mesa_unlock_context_textures(ctx);
 483 }
 484
 485
 486
 487
 488 /**
 489  * Want to figure out which fragment program inputs are actually
 490  * constant/current values from ctx->Current.  These should be
 491  * referenced as a tracked state variable rather than a fragment
 492  * program input, to save the overhead of putting a constant value in
 493  * every submitted vertex, transferring it to hardware, interpolating
 494  * it across the triangle, etc...
 495  *
 496  * When there is a VP bound, just use vp->outputs.  But when we're
 497  * generating vp from fixed function state, basically want to
 498  * calculate:
 499  *
 500  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 501  *                 potential_vp_outputs )
 502  *
 503  * Where potential_vp_outputs is calculated by looking at enabled
 504  * texgen, etc.
 505  *
 506  * The generated fragment program should then only declare inputs that
 507  * may vary or otherwise differ from the ctx->Current values.
 508  * Otherwise, the fp should track them as state values instead.
 509  */
 510 void
 511 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 512                              GLbitfield64 varying_inputs )
 513 {
 514    if (ctx->varying_vp_inputs != varying_inputs) {
 515       ctx->varying_vp_inputs = varying_inputs;
 516
 517       /* Only the fixed-func generated programs need to use the flag
 518        * and the fixed-func fragment program uses it only if there is also
 519        * a fixed-func vertex program, so this only depends on the latter.
 520        *
 521        * It's okay to check the VP pointer here, because this is called after
 522        * _mesa_update_state in the vbo module. */
 523       if (ctx->VertexProgram._TnlProgram ||
 524           ctx->FragmentProgram._TexEnvProgram) {
 525          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 526       }
 527       /*printf("%s %x\n", __func__, varying_inputs);*/
 528    }
 529 }
 530
 531
 532 /**
 533  * Used by drivers to tell core Mesa that the driver is going to
 534  * install/ use its own vertex program.  In particular, this will
 535  * prevent generated fragment programs from using state vars instead
 536  * of ordinary varyings/inputs.
 537  */
 538 void
 539 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 540 {
 541    if (ctx->VertexProgram._Overriden != flag) {
 542       ctx->VertexProgram._Overriden = flag;
 543
 544       /* Set one of the bits which will trigger fragment program
 545        * regeneration:
 546        */
 547       ctx->NewState |= _NEW_PROGRAM;
 548    }
 549 }