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->Base.Instructions;
  74    ctx->FragmentProgram._Enabled = ctx->FragmentProgram.Enabled
  75       && ctx->FragmentProgram.Current->Base.Instructions;
  76    ctx->ATIFragmentShader._Enabled = ctx->ATIFragmentShader.Enabled
  77       && ctx->ATIFragmentShader.Current->Instructions[0];
  78 }
  79
  80
  81 /**
  82  * Update the ctx->Vertex/Geometry/FragmentProgram._Current pointers to point
  83  * to the 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    const struct gl_shader_program *vsProg =
  99       ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
 100    const struct gl_shader_program *gsProg =
 101       ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
 102    struct gl_shader_program *fsProg =
 103       ctx->_Shader->CurrentProgram[MESA_SHADER_FRAGMENT];
 104    const struct gl_shader_program *csProg =
 105       ctx->_Shader->CurrentProgram[MESA_SHADER_COMPUTE];
 106    const struct gl_vertex_program *prevVP = ctx->VertexProgram._Current;
 107    const struct gl_fragment_program *prevFP = ctx->FragmentProgram._Current;
 108    const struct gl_geometry_program *prevGP = ctx->GeometryProgram._Current;
 109    const struct gl_compute_program *prevCP = ctx->ComputeProgram._Current;
 110    GLbitfield new_state = 0x0;
 111
 112    /*
 113     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 114     * pointers to the programs that should be used for rendering.  If either
 115     * is NULL, use fixed-function code paths.
 116     *
 117     * These programs may come from several sources.  The priority is as
 118     * follows:
 119     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 120     *   2. ARB/NV vertex/fragment programs
 121     *   3. Programs derived from fixed-function state.
 122     *
 123     * Note: it's possible for a vertex shader to get used with a fragment
 124     * program (and vice versa) here, but in practice that shouldn't ever
 125     * come up, or matter.
 126     */
 127
 128    if (fsProg && fsProg->LinkStatus
 129        && fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]) {
 130       /* Use GLSL fragment shader */
 131       _mesa_reference_shader_program(ctx,
 132                                      &ctx->_Shader->_CurrentFragmentProgram,
 133                                      fsProg);
 134       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 135                                gl_fragment_program(fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 136       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 137                                NULL);
 138    }
 139    else if (ctx->FragmentProgram._Enabled) {
 140       /* Use user-defined fragment program */
 141       _mesa_reference_shader_program(ctx,
 142                                      &ctx->_Shader->_CurrentFragmentProgram,
 143                                      NULL);
 144       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 145                                ctx->FragmentProgram.Current);
 146       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 147                                NULL);
 148    }
 149    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 150       /* Use fragment program generated from fixed-function state */
 151       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 152
 153       _mesa_reference_shader_program(ctx,
 154                                      &ctx->_Shader->_CurrentFragmentProgram,
 155                                      f);
 156       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 157                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 158       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 159                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 160    }
 161    else {
 162       /* No fragment program */
 163       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 164       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 165                                NULL);
 166    }
 167
 168    if (gsProg && gsProg->LinkStatus
 169        && gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]) {
 170       /* Use GLSL geometry shader */
 171       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current,
 172                                gl_geometry_program(gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]->Program));
 173    } else {
 174       /* No geometry program */
 175       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current, NULL);
 176    }
 177
 178    /* Examine vertex program after fragment program as
 179     * _mesa_get_fixed_func_vertex_program() needs to know active
 180     * fragprog inputs.
 181     */
 182    if (vsProg && vsProg->LinkStatus
 183        && vsProg->_LinkedShaders[MESA_SHADER_VERTEX]) {
 184       /* Use GLSL vertex shader */
 185       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 186                                gl_vertex_program(vsProg->_LinkedShaders[MESA_SHADER_VERTEX]->Program));
 187    }
 188    else if (ctx->VertexProgram._Enabled) {
 189       /* Use user-defined vertex program */
 190       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 191                                ctx->VertexProgram.Current);
 192    }
 193    else if (ctx->VertexProgram._MaintainTnlProgram) {
 194       /* Use vertex program generated from fixed-function state */
 195       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 196                                _mesa_get_fixed_func_vertex_program(ctx));
 197       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram,
 198                                ctx->VertexProgram._Current);
 199    }
 200    else {
 201       /* no vertex program */
 202       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 203    }
 204
 205    if (csProg && csProg->LinkStatus
 206        && csProg->_LinkedShaders[MESA_SHADER_COMPUTE]) {
 207       /* Use GLSL compute shader */
 208       _mesa_reference_compprog(ctx, &ctx->ComputeProgram._Current,
 209                                gl_compute_program(csProg->_LinkedShaders[MESA_SHADER_COMPUTE]->Program));
 210    } else {
 211       /* no compute program */
 212       _mesa_reference_compprog(ctx, &ctx->ComputeProgram._Current, NULL);
 213    }
 214
 215    /* Let the driver know what's happening:
 216     */
 217    if (ctx->FragmentProgram._Current != prevFP) {
 218       new_state |= _NEW_PROGRAM;
 219       if (ctx->Driver.BindProgram) {
 220          ctx->Driver.BindProgram(ctx, GL_FRAGMENT_PROGRAM_ARB,
 221                           (struct gl_program *) ctx->FragmentProgram._Current);
 222       }
 223    }
 224
 225    if (ctx->GeometryProgram._Current != prevGP) {
 226       new_state |= _NEW_PROGRAM;
 227       if (ctx->Driver.BindProgram) {
 228          ctx->Driver.BindProgram(ctx, GL_GEOMETRY_PROGRAM_NV,
 229                             (struct gl_program *) ctx->GeometryProgram._Current);
 230       }
 231    }
 232
 233    if (ctx->VertexProgram._Current != prevVP) {
 234       new_state |= _NEW_PROGRAM;
 235       if (ctx->Driver.BindProgram) {
 236          ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
 237                             (struct gl_program *) ctx->VertexProgram._Current);
 238       }
 239    }
 240
 241    if (ctx->ComputeProgram._Current != prevCP) {
 242       new_state |= _NEW_PROGRAM;
 243       if (ctx->Driver.BindProgram) {
 244          ctx->Driver.BindProgram(ctx, GL_COMPUTE_PROGRAM_NV,
 245                                  (struct gl_program *) ctx->ComputeProgram._Current);
 246       }
 247    }
 248
 249    return new_state;
 250 }
 251
 252
 253 /**
 254  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 255  */
 256 static GLbitfield
 257 update_program_constants(struct gl_context *ctx)
 258 {
 259    GLbitfield new_state = 0x0;
 260
 261    if (ctx->FragmentProgram._Current) {
 262       const struct gl_program_parameter_list *params =
 263          ctx->FragmentProgram._Current->Base.Parameters;
 264       if (params && params->StateFlags & ctx->NewState) {
 265          new_state |= _NEW_PROGRAM_CONSTANTS;
 266       }
 267    }
 268
 269    /* Don't handle geometry shaders here. They don't use any state
 270     * constants.
 271     */
 272
 273    if (ctx->VertexProgram._Current) {
 274       const struct gl_program_parameter_list *params =
 275          ctx->VertexProgram._Current->Base.Parameters;
 276       if (params && params->StateFlags & ctx->NewState) {
 277          new_state |= _NEW_PROGRAM_CONSTANTS;
 278       }
 279    }
 280
 281    return new_state;
 282 }
 283
 284
 285
 286
 287 /**
 288  * Update the ctx->Polygon._FrontBit flag.
 289  */
 290 static void
 291 update_frontbit(struct gl_context *ctx)
 292 {
 293    if (ctx->Transform.ClipOrigin == GL_LOWER_LEFT)
 294       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CW);
 295    else
 296       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CCW);
 297 }
 298
 299
 300 /**
 301  * Update derived multisample state.
 302  */
 303 static void
 304 update_multisample(struct gl_context *ctx)
 305 {
 306    ctx->Multisample._Enabled = GL_FALSE;
 307    if (ctx->Multisample.Enabled &&
 308        ctx->DrawBuffer &&
 309        ctx->DrawBuffer->Visual.sampleBuffers)
 310       ctx->Multisample._Enabled = GL_TRUE;
 311 }
 312
 313
 314 /**
 315  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 316  */
 317 static void
 318 update_twoside(struct gl_context *ctx)
 319 {
 320    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX] ||
 321        ctx->VertexProgram._Enabled) {
 322       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 323    } else {
 324       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 325                                             ctx->Light.Model.TwoSide);
 326    }
 327 }
 328
 329
 330 /**
 331  * Compute derived GL state.
 332  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 333  * be called before rendering anything.
 334  *
 335  * Calls dd_function_table::UpdateState to perform any internal state
 336  * management necessary.
 337  *
 338  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 339  * _mesa_update_buffer_bounds(),
 340  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 341  */
 342 void
 343 _mesa_update_state_locked( struct gl_context *ctx )
 344 {
 345    GLbitfield new_state = ctx->NewState;
 346    GLbitfield prog_flags = _NEW_PROGRAM;
 347    GLbitfield new_prog_state = 0x0;
 348
 349    if (new_state == _NEW_CURRENT_ATTRIB)
 350       goto out;
 351
 352    if (MESA_VERBOSE & VERBOSE_STATE)
 353       _mesa_print_state("_mesa_update_state", new_state);
 354
 355    /* Determine which state flags effect vertex/fragment program state */
 356    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 357       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 358                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 359                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 360                      _NEW_COLOR);
 361    }
 362    if (ctx->VertexProgram._MaintainTnlProgram) {
 363       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 364                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 365                      _NEW_FOG | _NEW_LIGHT |
 366                      _MESA_NEW_NEED_EYE_COORDS);
 367    }
 368
 369    /*
 370     * Now update derived state info
 371     */
 372
 373    if (new_state & prog_flags)
 374       update_program_enables( ctx );
 375
 376    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 377       _mesa_update_modelview_project( ctx, new_state );
 378
 379    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 380       _mesa_update_texture( ctx, new_state );
 381
 382    if (new_state & _NEW_POLYGON)
 383       update_frontbit( ctx );
 384
 385    if (new_state & _NEW_BUFFERS)
 386       _mesa_update_framebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer);
 387
 388    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 389       _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
 390
 391    if (new_state & _NEW_LIGHT)
 392       _mesa_update_lighting( ctx );
 393
 394    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 395       update_twoside( ctx );
 396
 397    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 398       _mesa_update_stencil( ctx );
 399
 400    if (new_state & _NEW_PIXEL)
 401       _mesa_update_pixel( ctx, new_state );
 402
 403    if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
 404       update_multisample( ctx );
 405
 406    /* ctx->_NeedEyeCoords is now up to date.
 407     *
 408     * If the truth value of this variable has changed, update for the
 409     * new lighting space and recompute the positions of lights and the
 410     * normal transform.
 411     *
 412     * If the lighting space hasn't changed, may still need to recompute
 413     * light positions & normal transforms for other reasons.
 414     */
 415    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 416       _mesa_update_tnl_spaces( ctx, new_state );
 417
 418    if (new_state & prog_flags) {
 419       /* When we generate programs from fixed-function vertex/fragment state
 420        * this call may generate/bind a new program.  If so, we need to
 421        * propogate the _NEW_PROGRAM flag to the driver.
 422        */
 423       new_prog_state |= update_program( ctx );
 424    }
 425
 426    if (new_state & _NEW_ARRAY)
 427       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 428
 429  out:
 430    new_prog_state |= update_program_constants(ctx);
 431
 432    /*
 433     * Give the driver a chance to act upon the new_state flags.
 434     * The driver might plug in different span functions, for example.
 435     * Also, this is where the driver can invalidate the state of any
 436     * active modules (such as swrast_setup, swrast, tnl, etc).
 437     *
 438     * Set ctx->NewState to zero to avoid recursion if
 439     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 440     */
 441    new_state = ctx->NewState | new_prog_state;
 442    ctx->NewState = 0;
 443    ctx->Driver.UpdateState(ctx, new_state);
 444    ctx->Array.VAO->NewArrays = 0x0;
 445 }
 446
 447
 448 /* This is the usual entrypoint for state updates:
 449  */
 450 void
 451 _mesa_update_state( struct gl_context *ctx )
 452 {
 453    _mesa_lock_context_textures(ctx);
 454    _mesa_update_state_locked(ctx);
 455    _mesa_unlock_context_textures(ctx);
 456 }
 457
 458
 459
 460
 461 /**
 462  * Want to figure out which fragment program inputs are actually
 463  * constant/current values from ctx->Current.  These should be
 464  * referenced as a tracked state variable rather than a fragment
 465  * program input, to save the overhead of putting a constant value in
 466  * every submitted vertex, transferring it to hardware, interpolating
 467  * it across the triangle, etc...
 468  *
 469  * When there is a VP bound, just use vp->outputs.  But when we're
 470  * generating vp from fixed function state, basically want to
 471  * calculate:
 472  *
 473  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 474  *                 potential_vp_outputs )
 475  *
 476  * Where potential_vp_outputs is calculated by looking at enabled
 477  * texgen, etc.
 478  *
 479  * The generated fragment program should then only declare inputs that
 480  * may vary or otherwise differ from the ctx->Current values.
 481  * Otherwise, the fp should track them as state values instead.
 482  */
 483 void
 484 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 485                              GLbitfield64 varying_inputs )
 486 {
 487    if (ctx->varying_vp_inputs != varying_inputs) {
 488       ctx->varying_vp_inputs = varying_inputs;
 489
 490       /* Only the fixed-func generated programs need to use the flag
 491        * and the fixed-func fragment program uses it only if there is also
 492        * a fixed-func vertex program, so this only depends on the latter.
 493        *
 494        * It's okay to check the VP pointer here, because this is called after
 495        * _mesa_update_state in the vbo module. */
 496       if (ctx->VertexProgram._TnlProgram ||
 497           ctx->FragmentProgram._TexEnvProgram) {
 498          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 499       }
 500       /*printf("%s %x\n", __func__, varying_inputs);*/
 501    }
 502 }
 503
 504
 505 /**
 506  * Used by drivers to tell core Mesa that the driver is going to
 507  * install/ use its own vertex program.  In particular, this will
 508  * prevent generated fragment programs from using state vars instead
 509  * of ordinary varyings/inputs.
 510  */
 511 void
 512 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 513 {
 514    if (ctx->VertexProgram._Overriden != flag) {
 515       ctx->VertexProgram._Overriden = flag;
 516
 517       /* Set one of the bits which will trigger fragment program
 518        * regeneration:
 519        */
 520       ctx->NewState |= _NEW_PROGRAM;
 521    }
 522 }