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.
  84  *
  85  * Programs may come from 3 sources: GLSL shaders, ARB/NV_vertex/fragment
  86  * programs or programs derived from fixed-function state.
  87  *
  88  * This function needs to be called after texture state validation in case
  89  * we're generating a fragment program from fixed-function texture state.
  90  *
  91  * \return bitfield which will indicate _NEW_PROGRAM state if a new vertex
  92  * or fragment program is being used.
  93  */
  94 static GLbitfield
  95 update_program(struct gl_context *ctx)
  96 {
  97    struct gl_program *vsProg =
  98       ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
  99    struct gl_program *tcsProg =
 100       ctx->_Shader->CurrentProgram[MESA_SHADER_TESS_CTRL];
 101    struct gl_program *tesProg =
 102       ctx->_Shader->CurrentProgram[MESA_SHADER_TESS_EVAL];
 103    struct gl_program *gsProg =
 104       ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
 105    struct gl_program *fsProg =
 106       ctx->_Shader->CurrentProgram[MESA_SHADER_FRAGMENT];
 107    struct gl_program *csProg =
 108       ctx->_Shader->CurrentProgram[MESA_SHADER_COMPUTE];
 109    const struct gl_program *prevVP = ctx->VertexProgram._Current;
 110    const struct gl_program *prevFP = ctx->FragmentProgram._Current;
 111    const struct gl_program *prevGP = ctx->GeometryProgram._Current;
 112    const struct gl_program *prevTCP = ctx->TessCtrlProgram._Current;
 113    const struct gl_program *prevTEP = ctx->TessEvalProgram._Current;
 114    const struct gl_program *prevCP = ctx->ComputeProgram._Current;
 115    GLbitfield new_state = 0x0;
 116
 117    /*
 118     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 119     * pointers to the programs that should be used for rendering.  If either
 120     * is NULL, use fixed-function code paths.
 121     *
 122     * These programs may come from several sources.  The priority is as
 123     * follows:
 124     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 125     *   2. ARB/NV vertex/fragment programs
 126     *   3. ATI fragment shader
 127     *   4. Programs derived from fixed-function state.
 128     *
 129     * Note: it's possible for a vertex shader to get used with a fragment
 130     * program (and vice versa) here, but in practice that shouldn't ever
 131     * come up, or matter.
 132     */
 133
 134    if (fsProg) {
 135       /* Use GLSL fragment shader */
 136       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 137                               fsProg);
 138       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, fsProg);
 139       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 140                               NULL);
 141    }
 142    else if (ctx->FragmentProgram._Enabled) {
 143       /* Use user-defined fragment program */
 144       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 145                               NULL);
 146       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 147                               ctx->FragmentProgram.Current);
 148       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 149                               NULL);
 150    }
 151    else if (ctx->ATIFragmentShader._Enabled &&
 152             ctx->ATIFragmentShader.Current->Program) {
 153        /* Use the enabled ATI fragment shader's associated program */
 154       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 155                               NULL);
 156       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 157                               ctx->ATIFragmentShader.Current->Program);
 158       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 159                               NULL);
 160    }
 161    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 162       /* Use fragment program generated from fixed-function state */
 163       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 164
 165       _mesa_reference_program(ctx, &ctx->_Shader->_CurrentFragmentProgram,
 166                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 167       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 168                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 169       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 170                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 171    }
 172    else {
 173       /* No fragment program */
 174       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, NULL);
 175       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 176                               NULL);
 177    }
 178
 179    if (gsProg) {
 180       /* Use GLSL geometry shader */
 181       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, gsProg);
 182    } else {
 183       /* No geometry program */
 184       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, NULL);
 185    }
 186
 187    if (tesProg) {
 188       /* Use GLSL tessellation evaluation shader */
 189       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, tesProg);
 190    }
 191    else {
 192       /* No tessellation evaluation program */
 193       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, NULL);
 194    }
 195
 196    if (tcsProg) {
 197       /* Use GLSL tessellation control shader */
 198       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, tcsProg);
 199    }
 200    else {
 201       /* No tessellation control program */
 202       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, NULL);
 203    }
 204
 205    /* Examine vertex program after fragment program as
 206     * _mesa_get_fixed_func_vertex_program() needs to know active
 207     * fragprog inputs.
 208     */
 209    if (vsProg) {
 210       /* Use GLSL vertex shader */
 211       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, vsProg);
 212    }
 213    else if (ctx->VertexProgram._Enabled) {
 214       /* Use user-defined vertex program */
 215       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 216                               ctx->VertexProgram.Current);
 217    }
 218    else if (ctx->VertexProgram._MaintainTnlProgram) {
 219       /* Use vertex program generated from fixed-function state */
 220       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 221                               _mesa_get_fixed_func_vertex_program(ctx));
 222       _mesa_reference_program(ctx, &ctx->VertexProgram._TnlProgram,
 223                               ctx->VertexProgram._Current);
 224    }
 225    else {
 226       /* no vertex program */
 227       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, NULL);
 228    }
 229
 230    if (csProg) {
 231       /* Use GLSL compute shader */
 232       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, csProg);
 233    } else {
 234       /* no compute program */
 235       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, NULL);
 236    }
 237
 238    /* Let the driver know what's happening:
 239     */
 240    if (ctx->FragmentProgram._Current != prevFP ||
 241        ctx->VertexProgram._Current != prevVP ||
 242        ctx->GeometryProgram._Current != prevGP ||
 243        ctx->TessEvalProgram._Current != prevTEP ||
 244        ctx->TessCtrlProgram._Current != prevTCP ||
 245        ctx->ComputeProgram._Current != prevCP)
 246       new_state |= _NEW_PROGRAM;
 247
 248    return new_state;
 249 }
 250
 251
 252 /**
 253  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 254  */
 255 static GLbitfield
 256 update_program_constants(struct gl_context *ctx)
 257 {
 258    GLbitfield new_state = 0x0;
 259
 260    if (ctx->FragmentProgram._Current) {
 261       const struct gl_program_parameter_list *params =
 262          ctx->FragmentProgram._Current->Parameters;
 263       if (params && params->StateFlags & ctx->NewState) {
 264          new_state |= _NEW_PROGRAM_CONSTANTS;
 265       }
 266    }
 267
 268    /* Don't handle tessellation and geometry shaders here. They don't use
 269     * any state constants.
 270     */
 271
 272    if (ctx->VertexProgram._Current) {
 273       const struct gl_program_parameter_list *params =
 274          ctx->VertexProgram._Current->Parameters;
 275       if (params && params->StateFlags & ctx->NewState) {
 276          new_state |= _NEW_PROGRAM_CONSTANTS;
 277       }
 278    }
 279
 280    return new_state;
 281 }
 282
 283
 284
 285
 286 /**
 287  * Update the ctx->Polygon._FrontBit flag.
 288  */
 289 static void
 290 update_frontbit(struct gl_context *ctx)
 291 {
 292    if (ctx->Transform.ClipOrigin == GL_LOWER_LEFT)
 293       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CW);
 294    else
 295       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CCW);
 296 }
 297
 298
 299 /**
 300  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 301  */
 302 static void
 303 update_twoside(struct gl_context *ctx)
 304 {
 305    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX] ||
 306        ctx->VertexProgram._Enabled) {
 307       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 308    } else {
 309       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 310                                             ctx->Light.Model.TwoSide);
 311    }
 312 }
 313
 314
 315 /**
 316  * Compute derived GL state.
 317  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 318  * be called before rendering anything.
 319  *
 320  * Calls dd_function_table::UpdateState to perform any internal state
 321  * management necessary.
 322  *
 323  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 324  * _mesa_update_buffer_bounds(),
 325  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 326  */
 327 void
 328 _mesa_update_state_locked( struct gl_context *ctx )
 329 {
 330    GLbitfield new_state = ctx->NewState;
 331    GLbitfield prog_flags = _NEW_PROGRAM;
 332    GLbitfield new_prog_state = 0x0;
 333    const GLbitfield computed_states = ~(_NEW_CURRENT_ATTRIB | _NEW_LINE);
 334
 335    /* we can skip a bunch of state validation checks if the dirty
 336     * state matches one or more bits in 'computed_states'.
 337     */
 338    if ((new_state & computed_states) == 0)
 339       goto out;
 340
 341    if (MESA_VERBOSE & VERBOSE_STATE)
 342       _mesa_print_state("_mesa_update_state", new_state);
 343
 344    /* Determine which state flags effect vertex/fragment program state */
 345    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 346       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE_OBJECT | _NEW_FOG |
 347                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 348                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 349                      _NEW_COLOR | _NEW_TEXTURE_STATE);
 350    }
 351    if (ctx->VertexProgram._MaintainTnlProgram) {
 352       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE_OBJECT |
 353                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 354                      _NEW_FOG | _NEW_LIGHT | _NEW_TEXTURE_STATE |
 355                      _MESA_NEW_NEED_EYE_COORDS);
 356    }
 357
 358    /*
 359     * Now update derived state info
 360     */
 361
 362    if (new_state & prog_flags)
 363       update_program_enables( ctx );
 364
 365    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 366       _mesa_update_modelview_project( ctx, new_state );
 367
 368    if (new_state & _NEW_TEXTURE_MATRIX)
 369       _mesa_update_texture_matrices(ctx);
 370
 371    if (new_state & (_NEW_TEXTURE_OBJECT | _NEW_TEXTURE_STATE | _NEW_PROGRAM))
 372       _mesa_update_texture_state(ctx);
 373
 374    if (new_state & _NEW_POLYGON)
 375       update_frontbit( ctx );
 376
 377    if (new_state & _NEW_BUFFERS)
 378       _mesa_update_framebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer);
 379
 380    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 381       _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
 382
 383    if (new_state & _NEW_LIGHT)
 384       _mesa_update_lighting( ctx );
 385
 386    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 387       update_twoside( ctx );
 388
 389    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 390       _mesa_update_stencil( ctx );
 391
 392    if (new_state & _NEW_PIXEL)
 393       _mesa_update_pixel( ctx, new_state );
 394
 395    /* ctx->_NeedEyeCoords is now up to date.
 396     *
 397     * If the truth value of this variable has changed, update for the
 398     * new lighting space and recompute the positions of lights and the
 399     * normal transform.
 400     *
 401     * If the lighting space hasn't changed, may still need to recompute
 402     * light positions & normal transforms for other reasons.
 403     */
 404    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 405       _mesa_update_tnl_spaces( ctx, new_state );
 406
 407    if (new_state & prog_flags) {
 408       /* When we generate programs from fixed-function vertex/fragment state
 409        * this call may generate/bind a new program.  If so, we need to
 410        * propogate the _NEW_PROGRAM flag to the driver.
 411        */
 412       new_prog_state |= update_program( ctx );
 413    }
 414
 415    if (new_state & _NEW_ARRAY)
 416       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 417
 418  out:
 419    new_prog_state |= update_program_constants(ctx);
 420
 421    /*
 422     * Give the driver a chance to act upon the new_state flags.
 423     * The driver might plug in different span functions, for example.
 424     * Also, this is where the driver can invalidate the state of any
 425     * active modules (such as swrast_setup, swrast, tnl, etc).
 426     *
 427     * Set ctx->NewState to zero to avoid recursion if
 428     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 429     */
 430    new_state = ctx->NewState | new_prog_state;
 431    ctx->NewState = 0;
 432    ctx->Driver.UpdateState(ctx, new_state);
 433    ctx->Array.VAO->NewArrays = 0x0;
 434 }
 435
 436
 437 /* This is the usual entrypoint for state updates:
 438  */
 439 void
 440 _mesa_update_state( struct gl_context *ctx )
 441 {
 442    _mesa_lock_context_textures(ctx);
 443    _mesa_update_state_locked(ctx);
 444    _mesa_unlock_context_textures(ctx);
 445 }
 446
 447
 448
 449
 450 /**
 451  * Want to figure out which fragment program inputs are actually
 452  * constant/current values from ctx->Current.  These should be
 453  * referenced as a tracked state variable rather than a fragment
 454  * program input, to save the overhead of putting a constant value in
 455  * every submitted vertex, transferring it to hardware, interpolating
 456  * it across the triangle, etc...
 457  *
 458  * When there is a VP bound, just use vp->outputs.  But when we're
 459  * generating vp from fixed function state, basically want to
 460  * calculate:
 461  *
 462  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 463  *                 potential_vp_outputs )
 464  *
 465  * Where potential_vp_outputs is calculated by looking at enabled
 466  * texgen, etc.
 467  *
 468  * The generated fragment program should then only declare inputs that
 469  * may vary or otherwise differ from the ctx->Current values.
 470  * Otherwise, the fp should track them as state values instead.
 471  */
 472 void
 473 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 474                              GLbitfield64 varying_inputs )
 475 {
 476    if (ctx->varying_vp_inputs != varying_inputs) {
 477       ctx->varying_vp_inputs = varying_inputs;
 478
 479       /* Only the fixed-func generated programs need to use the flag
 480        * and the fixed-func fragment program uses it only if there is also
 481        * a fixed-func vertex program, so this only depends on the latter.
 482        *
 483        * It's okay to check the VP pointer here, because this is called after
 484        * _mesa_update_state in the vbo module. */
 485       if (ctx->VertexProgram._TnlProgram ||
 486           ctx->FragmentProgram._TexEnvProgram) {
 487          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 488       }
 489       /*printf("%s %x\n", __func__, varying_inputs);*/
 490    }
 491 }
 492
 493
 494 /**
 495  * Used by drivers to tell core Mesa that the driver is going to
 496  * install/ use its own vertex program.  In particular, this will
 497  * prevent generated fragment programs from using state vars instead
 498  * of ordinary varyings/inputs.
 499  */
 500 void
 501 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 502 {
 503    if (ctx->VertexProgram._Overriden != flag) {
 504       ctx->VertexProgram._Overriden = flag;
 505
 506       /* Set one of the bits which will trigger fragment program
 507        * regeneration:
 508        */
 509       ctx->NewState |= _NEW_PROGRAM;
 510    }
 511 }