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 "vbo/vbo_context.h"
  55 #include "viewport.h"
  56 #include "blend.h"
  57
  58
  59 /**
  60  * Update the following fields:
  61  *   ctx->VertexProgram._Enabled
  62  *   ctx->FragmentProgram._Enabled
  63  *   ctx->ATIFragmentShader._Enabled
  64  * This needs to be done before texture state validation.
  65  */
  66 static void
  67 update_program_enables(struct gl_context *ctx)
  68 {
  69    /* These _Enabled flags indicate if the user-defined ARB/NV vertex/fragment
  70     * program is enabled AND valid.  Similarly for ATI fragment shaders.
  71     * GLSL shaders not relevant here.
  72     */
  73    ctx->VertexProgram._Enabled = ctx->VertexProgram.Enabled
  74       && ctx->VertexProgram.Current->arb.Instructions;
  75    ctx->FragmentProgram._Enabled = ctx->FragmentProgram.Enabled
  76       && ctx->FragmentProgram.Current->arb.Instructions;
  77    ctx->ATIFragmentShader._Enabled = ctx->ATIFragmentShader.Enabled
  78       && ctx->ATIFragmentShader.Current->Instructions[0];
  79 }
  80
  81
  82 /**
  83  * Update the ctx->*Program._Current pointers to point to the
  84  * current/active programs.
  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->FragmentProgram._Current, fsProg);
 138       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 139                               NULL);
 140    }
 141    else if (ctx->FragmentProgram._Enabled) {
 142       /* Use user-defined fragment program */
 143       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 144                               ctx->FragmentProgram.Current);
 145       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 146                               NULL);
 147    }
 148    else if (ctx->ATIFragmentShader._Enabled &&
 149             ctx->ATIFragmentShader.Current->Program) {
 150        /* Use the enabled ATI fragment shader's associated program */
 151       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 152                               ctx->ATIFragmentShader.Current->Program);
 153       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 154                               NULL);
 155    }
 156    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 157       /* Use fragment program generated from fixed-function state */
 158       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 159
 160       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current,
 161                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 162       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 163                               f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program);
 164    }
 165    else {
 166       /* No fragment program */
 167       _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, NULL);
 168       _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram,
 169                               NULL);
 170    }
 171
 172    if (gsProg) {
 173       /* Use GLSL geometry shader */
 174       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, gsProg);
 175    } else {
 176       /* No geometry program */
 177       _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, NULL);
 178    }
 179
 180    if (tesProg) {
 181       /* Use GLSL tessellation evaluation shader */
 182       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, tesProg);
 183    }
 184    else {
 185       /* No tessellation evaluation program */
 186       _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, NULL);
 187    }
 188
 189    if (tcsProg) {
 190       /* Use GLSL tessellation control shader */
 191       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, tcsProg);
 192    }
 193    else {
 194       /* No tessellation control program */
 195       _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, NULL);
 196    }
 197
 198    /* Examine vertex program after fragment program as
 199     * _mesa_get_fixed_func_vertex_program() needs to know active
 200     * fragprog inputs.
 201     */
 202    if (vsProg) {
 203       /* Use GLSL vertex shader */
 204       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, vsProg);
 205    }
 206    else if (ctx->VertexProgram._Enabled) {
 207       /* Use user-defined vertex program */
 208       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 209                               ctx->VertexProgram.Current);
 210    }
 211    else if (ctx->VertexProgram._MaintainTnlProgram) {
 212       /* Use vertex program generated from fixed-function state */
 213       _mesa_reference_program(ctx, &ctx->VertexProgram._Current,
 214                               _mesa_get_fixed_func_vertex_program(ctx));
 215       _mesa_reference_program(ctx, &ctx->VertexProgram._TnlProgram,
 216                               ctx->VertexProgram._Current);
 217    }
 218    else {
 219       /* no vertex program */
 220       _mesa_reference_program(ctx, &ctx->VertexProgram._Current, NULL);
 221    }
 222
 223    if (csProg) {
 224       /* Use GLSL compute shader */
 225       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, csProg);
 226    } else {
 227       /* no compute program */
 228       _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, NULL);
 229    }
 230
 231    /* Let the driver know what's happening:
 232     */
 233    if (ctx->FragmentProgram._Current != prevFP ||
 234        ctx->VertexProgram._Current != prevVP ||
 235        ctx->GeometryProgram._Current != prevGP ||
 236        ctx->TessEvalProgram._Current != prevTEP ||
 237        ctx->TessCtrlProgram._Current != prevTCP ||
 238        ctx->ComputeProgram._Current != prevCP)
 239       new_state |= _NEW_PROGRAM;
 240
 241    return new_state;
 242 }
 243
 244
 245 /**
 246  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 247  */
 248 static GLbitfield
 249 update_program_constants(struct gl_context *ctx)
 250 {
 251    GLbitfield new_state = 0x0;
 252
 253    if (ctx->FragmentProgram._Current) {
 254       const struct gl_program_parameter_list *params =
 255          ctx->FragmentProgram._Current->Parameters;
 256       if (params && params->StateFlags & ctx->NewState) {
 257          new_state |= _NEW_PROGRAM_CONSTANTS;
 258       }
 259    }
 260
 261    /* Don't handle tessellation and geometry shaders here. They don't use
 262     * any state constants.
 263     */
 264
 265    if (ctx->VertexProgram._Current) {
 266       const struct gl_program_parameter_list *params =
 267          ctx->VertexProgram._Current->Parameters;
 268       if (params && params->StateFlags & ctx->NewState) {
 269          new_state |= _NEW_PROGRAM_CONSTANTS;
 270       }
 271    }
 272
 273    return new_state;
 274 }
 275
 276
 277
 278
 279 /**
 280  * Update the ctx->Polygon._FrontBit flag.
 281  */
 282 static void
 283 update_frontbit(struct gl_context *ctx)
 284 {
 285    if (ctx->Transform.ClipOrigin == GL_LOWER_LEFT)
 286       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CW);
 287    else
 288       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CCW);
 289 }
 290
 291
 292 /**
 293  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 294  */
 295 static void
 296 update_twoside(struct gl_context *ctx)
 297 {
 298    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX] ||
 299        ctx->VertexProgram._Enabled) {
 300       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 301    } else {
 302       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 303                                             ctx->Light.Model.TwoSide);
 304    }
 305 }
 306
 307
 308 /**
 309  * Compute derived GL state.
 310  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 311  * be called before rendering anything.
 312  *
 313  * Calls dd_function_table::UpdateState to perform any internal state
 314  * management necessary.
 315  *
 316  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 317  * _mesa_update_buffer_bounds(),
 318  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 319  */
 320 void
 321 _mesa_update_state_locked( struct gl_context *ctx )
 322 {
 323    GLbitfield new_state = ctx->NewState;
 324    GLbitfield prog_flags = _NEW_PROGRAM;
 325    GLbitfield new_prog_state = 0x0;
 326    const GLbitfield computed_states = ~(_NEW_CURRENT_ATTRIB | _NEW_LINE);
 327
 328    /* we can skip a bunch of state validation checks if the dirty
 329     * state matches one or more bits in 'computed_states'.
 330     */
 331    if ((new_state & computed_states) == 0)
 332       goto out;
 333
 334    if (MESA_VERBOSE & VERBOSE_STATE)
 335       _mesa_print_state("_mesa_update_state", new_state);
 336
 337    /* Determine which state flags effect vertex/fragment program state */
 338    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 339       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE_OBJECT | _NEW_FOG |
 340                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 341                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 342                      _NEW_COLOR | _NEW_TEXTURE_STATE);
 343    }
 344    if (ctx->VertexProgram._MaintainTnlProgram) {
 345       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE_OBJECT |
 346                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 347                      _NEW_FOG | _NEW_LIGHT | _NEW_TEXTURE_STATE |
 348                      _MESA_NEW_NEED_EYE_COORDS);
 349    }
 350
 351    /*
 352     * Now update derived state info
 353     */
 354
 355    if (new_state & prog_flags)
 356       update_program_enables( ctx );
 357
 358    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 359       _mesa_update_modelview_project( ctx, new_state );
 360
 361    if (new_state & _NEW_TEXTURE_MATRIX)
 362       _mesa_update_texture_matrices(ctx);
 363
 364    if (new_state & (_NEW_TEXTURE_OBJECT | _NEW_TEXTURE_STATE | _NEW_PROGRAM))
 365       _mesa_update_texture_state(ctx);
 366
 367    if (new_state & _NEW_POLYGON)
 368       update_frontbit( ctx );
 369
 370    if (new_state & _NEW_BUFFERS)
 371       _mesa_update_framebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer);
 372
 373    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 374       _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
 375
 376    if (new_state & _NEW_LIGHT)
 377       _mesa_update_lighting( ctx );
 378
 379    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 380       update_twoside( ctx );
 381
 382    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 383       _mesa_update_stencil( ctx );
 384
 385    if (new_state & _NEW_PIXEL)
 386       _mesa_update_pixel( ctx );
 387
 388    /* ctx->_NeedEyeCoords is now up to date.
 389     *
 390     * If the truth value of this variable has changed, update for the
 391     * new lighting space and recompute the positions of lights and the
 392     * normal transform.
 393     *
 394     * If the lighting space hasn't changed, may still need to recompute
 395     * light positions & normal transforms for other reasons.
 396     */
 397    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 398       _mesa_update_tnl_spaces( ctx, new_state );
 399
 400    if (new_state & prog_flags) {
 401       /* When we generate programs from fixed-function vertex/fragment state
 402        * this call may generate/bind a new program.  If so, we need to
 403        * propogate the _NEW_PROGRAM flag to the driver.
 404        */
 405       new_prog_state |= update_program( ctx );
 406    }
 407
 408    if (new_state & _NEW_ARRAY)
 409       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 410
 411  out:
 412    new_prog_state |= update_program_constants(ctx);
 413
 414    ctx->NewState |= new_prog_state;
 415    vbo_exec_invalidate_state(ctx);
 416
 417    /*
 418     * Give the driver a chance to act upon the new_state flags.
 419     * The driver might plug in different span functions, for example.
 420     * Also, this is where the driver can invalidate the state of any
 421     * active modules (such as swrast_setup, swrast, tnl, etc).
 422     */
 423    ctx->Driver.UpdateState(ctx);
 424    ctx->NewState = 0;
 425    ctx->Array.VAO->NewArrays = 0x0;
 426 }
 427
 428
 429 /* This is the usual entrypoint for state updates:
 430  */
 431 void
 432 _mesa_update_state( struct gl_context *ctx )
 433 {
 434    _mesa_lock_context_textures(ctx);
 435    _mesa_update_state_locked(ctx);
 436    _mesa_unlock_context_textures(ctx);
 437 }
 438
 439
 440
 441
 442 /**
 443  * Want to figure out which fragment program inputs are actually
 444  * constant/current values from ctx->Current.  These should be
 445  * referenced as a tracked state variable rather than a fragment
 446  * program input, to save the overhead of putting a constant value in
 447  * every submitted vertex, transferring it to hardware, interpolating
 448  * it across the triangle, etc...
 449  *
 450  * When there is a VP bound, just use vp->outputs.  But when we're
 451  * generating vp from fixed function state, basically want to
 452  * calculate:
 453  *
 454  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 455  *                 potential_vp_outputs )
 456  *
 457  * Where potential_vp_outputs is calculated by looking at enabled
 458  * texgen, etc.
 459  *
 460  * The generated fragment program should then only declare inputs that
 461  * may vary or otherwise differ from the ctx->Current values.
 462  * Otherwise, the fp should track them as state values instead.
 463  */
 464 void
 465 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 466                              GLbitfield64 varying_inputs )
 467 {
 468    if (ctx->varying_vp_inputs != varying_inputs) {
 469       ctx->varying_vp_inputs = varying_inputs;
 470
 471       /* Only the fixed-func generated programs need to use the flag
 472        * and the fixed-func fragment program uses it only if there is also
 473        * a fixed-func vertex program, so this only depends on the latter.
 474        *
 475        * It's okay to check the VP pointer here, because this is called after
 476        * _mesa_update_state in the vbo module. */
 477       if (ctx->VertexProgram._TnlProgram ||
 478           ctx->FragmentProgram._TexEnvProgram) {
 479          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 480       }
 481       /*printf("%s %x\n", __func__, varying_inputs);*/
 482    }
 483 }
 484
 485
 486 /**
 487  * Used by drivers to tell core Mesa that the driver is going to
 488  * install/ use its own vertex program.  In particular, this will
 489  * prevent generated fragment programs from using state vars instead
 490  * of ordinary varyings/inputs.
 491  */
 492 void
 493 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 494 {
 495    if (ctx->VertexProgram._Overriden != flag) {
 496       ctx->VertexProgram._Overriden = flag;
 497
 498       /* Set one of the bits which will trigger fragment program
 499        * regeneration:
 500        */
 501       ctx->NewState |= _NEW_PROGRAM;
 502    }
 503 }