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 "blend.h"
  55
  56
  57 /**
  58  * Update the following fields:
  59  *   ctx->VertexProgram._Enabled
  60  *   ctx->FragmentProgram._Enabled
  61  *   ctx->ATIFragmentShader._Enabled
  62  * This needs to be done before texture state validation.
  63  */
  64 static void
  65 update_program_enables(struct gl_context *ctx)
  66 {
  67    /* These _Enabled flags indicate if the user-defined ARB/NV vertex/fragment
  68     * program is enabled AND valid.  Similarly for ATI fragment shaders.
  69     * GLSL shaders not relevant here.
  70     */
  71    ctx->VertexProgram._Enabled = ctx->VertexProgram.Enabled
  72       && ctx->VertexProgram.Current->Base.Instructions;
  73    ctx->FragmentProgram._Enabled = ctx->FragmentProgram.Enabled
  74       && ctx->FragmentProgram.Current->Base.Instructions;
  75    ctx->ATIFragmentShader._Enabled = ctx->ATIFragmentShader.Enabled
  76       && ctx->ATIFragmentShader.Current->Instructions[0];
  77 }
  78
  79
  80 /**
  81  * Update the ctx->Vertex/Geometry/FragmentProgram._Current pointers to point
  82  * to the current/active programs.  Then call ctx->Driver.BindProgram() to
  83  * tell the driver which programs to use.
  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    const struct gl_shader_program *vsProg =
  98       ctx->Shader.CurrentProgram[MESA_SHADER_VERTEX];
  99    const struct gl_shader_program *gsProg =
 100       ctx->Shader.CurrentProgram[MESA_SHADER_GEOMETRY];
 101    struct gl_shader_program *fsProg =
 102       ctx->Shader.CurrentProgram[MESA_SHADER_FRAGMENT];
 103    const struct gl_vertex_program *prevVP = ctx->VertexProgram._Current;
 104    const struct gl_fragment_program *prevFP = ctx->FragmentProgram._Current;
 105    const struct gl_geometry_program *prevGP = ctx->GeometryProgram._Current;
 106    GLbitfield new_state = 0x0;
 107
 108    /*
 109     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 110     * pointers to the programs that should be used for rendering.  If either
 111     * is NULL, use fixed-function code paths.
 112     *
 113     * These programs may come from several sources.  The priority is as
 114     * follows:
 115     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 116     *   2. ARB/NV vertex/fragment programs
 117     *   3. Programs derived from fixed-function state.
 118     *
 119     * Note: it's possible for a vertex shader to get used with a fragment
 120     * program (and vice versa) here, but in practice that shouldn't ever
 121     * come up, or matter.
 122     */
 123
 124    if (fsProg && fsProg->LinkStatus
 125        && fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]) {
 126       /* Use GLSL fragment shader */
 127       _mesa_reference_shader_program(ctx,
 128                                      &ctx->Shader._CurrentFragmentProgram,
 129                                      fsProg);
 130       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 131                                gl_fragment_program(fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 132       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 133                                NULL);
 134    }
 135    else if (ctx->FragmentProgram._Enabled) {
 136       /* Use user-defined fragment program */
 137       _mesa_reference_shader_program(ctx,
 138                                      &ctx->Shader._CurrentFragmentProgram,
 139                                      NULL);
 140       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 141                                ctx->FragmentProgram.Current);
 142       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 143                                NULL);
 144    }
 145    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 146       /* Use fragment program generated from fixed-function state */
 147       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 148
 149       _mesa_reference_shader_program(ctx,
 150                                      &ctx->Shader._CurrentFragmentProgram,
 151                                      f);
 152       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 153                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 154       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 155                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 156    }
 157    else {
 158       /* No fragment program */
 159       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 160       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 161                                NULL);
 162    }
 163
 164    if (gsProg && gsProg->LinkStatus
 165        && gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]) {
 166       /* Use GLSL geometry shader */
 167       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current,
 168                                gl_geometry_program(gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]->Program));
 169    } else {
 170       /* No geometry program */
 171       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current, NULL);
 172    }
 173
 174    /* Examine vertex program after fragment program as
 175     * _mesa_get_fixed_func_vertex_program() needs to know active
 176     * fragprog inputs.
 177     */
 178    if (vsProg && vsProg->LinkStatus
 179        && vsProg->_LinkedShaders[MESA_SHADER_VERTEX]) {
 180       /* Use GLSL vertex shader */
 181       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 182                                gl_vertex_program(vsProg->_LinkedShaders[MESA_SHADER_VERTEX]->Program));
 183    }
 184    else if (ctx->VertexProgram._Enabled) {
 185       /* Use user-defined vertex program */
 186       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 187                                ctx->VertexProgram.Current);
 188    }
 189    else if (ctx->VertexProgram._MaintainTnlProgram) {
 190       /* Use vertex program generated from fixed-function state */
 191       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 192                                _mesa_get_fixed_func_vertex_program(ctx));
 193       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram,
 194                                ctx->VertexProgram._Current);
 195    }
 196    else {
 197       /* no vertex program */
 198       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 199    }
 200
 201    /* Let the driver know what's happening:
 202     */
 203    if (ctx->FragmentProgram._Current != prevFP) {
 204       new_state |= _NEW_PROGRAM;
 205       if (ctx->Driver.BindProgram) {
 206          ctx->Driver.BindProgram(ctx, GL_FRAGMENT_PROGRAM_ARB,
 207                           (struct gl_program *) ctx->FragmentProgram._Current);
 208       }
 209    }
 210
 211    if (ctx->GeometryProgram._Current != prevGP) {
 212       new_state |= _NEW_PROGRAM;
 213       if (ctx->Driver.BindProgram) {
 214          ctx->Driver.BindProgram(ctx, MESA_GEOMETRY_PROGRAM,
 215                             (struct gl_program *) ctx->GeometryProgram._Current);
 216       }
 217    }
 218
 219    if (ctx->VertexProgram._Current != prevVP) {
 220       new_state |= _NEW_PROGRAM;
 221       if (ctx->Driver.BindProgram) {
 222          ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
 223                             (struct gl_program *) ctx->VertexProgram._Current);
 224       }
 225    }
 226
 227    return new_state;
 228 }
 229
 230
 231 /**
 232  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 233  */
 234 static GLbitfield
 235 update_program_constants(struct gl_context *ctx)
 236 {
 237    GLbitfield new_state = 0x0;
 238
 239    if (ctx->FragmentProgram._Current) {
 240       const struct gl_program_parameter_list *params =
 241          ctx->FragmentProgram._Current->Base.Parameters;
 242       if (params && params->StateFlags & ctx->NewState) {
 243          new_state |= _NEW_PROGRAM_CONSTANTS;
 244       }
 245    }
 246
 247    if (ctx->GeometryProgram._Current) {
 248       const struct gl_program_parameter_list *params =
 249          ctx->GeometryProgram._Current->Base.Parameters;
 250       /*FIXME: StateFlags is always 0 because we have unnamed constant
 251        *       not state changes */
 252       if (params /*&& params->StateFlags & ctx->NewState*/) {
 253          new_state |= _NEW_PROGRAM_CONSTANTS;
 254       }
 255    }
 256
 257    if (ctx->VertexProgram._Current) {
 258       const struct gl_program_parameter_list *params =
 259          ctx->VertexProgram._Current->Base.Parameters;
 260       if (params && params->StateFlags & ctx->NewState) {
 261          new_state |= _NEW_PROGRAM_CONSTANTS;
 262       }
 263    }
 264
 265    return new_state;
 266 }
 267
 268
 269
 270
 271 static void
 272 update_viewport_matrix(struct gl_context *ctx)
 273 {
 274    const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
 275    unsigned i;
 276
 277    ASSERT(depthMax > 0);
 278
 279    /* Compute scale and bias values. This is really driver-specific
 280     * and should be maintained elsewhere if at all.
 281     * NOTE: RasterPos uses this.
 282     */
 283    for (i = 0; i < ctx->Const.MaxViewports; i++) {
 284       _math_matrix_viewport(&ctx->ViewportArray[i]._WindowMap,
 285                             ctx->ViewportArray[i].X, ctx->ViewportArray[i].Y,
 286                             ctx->ViewportArray[i].Width, ctx->ViewportArray[i].Height,
 287                             ctx->ViewportArray[i].Near, ctx->ViewportArray[i].Far,
 288                             depthMax);
 289    }
 290 }
 291
 292
 293 /**
 294  * Update derived multisample state.
 295  */
 296 static void
 297 update_multisample(struct gl_context *ctx)
 298 {
 299    ctx->Multisample._Enabled = GL_FALSE;
 300    if (ctx->Multisample.Enabled &&
 301        ctx->DrawBuffer &&
 302        ctx->DrawBuffer->Visual.sampleBuffers)
 303       ctx->Multisample._Enabled = GL_TRUE;
 304 }
 305
 306
 307 /**
 308  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 309  */
 310 static void
 311 update_twoside(struct gl_context *ctx)
 312 {
 313    if (ctx->Shader.CurrentProgram[MESA_SHADER_VERTEX] ||
 314        ctx->VertexProgram._Enabled) {
 315       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 316    } else {
 317       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 318                                             ctx->Light.Model.TwoSide);
 319    }
 320 }
 321
 322
 323 /**
 324  * Compute derived GL state.
 325  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 326  * be called before rendering anything.
 327  *
 328  * Calls dd_function_table::UpdateState to perform any internal state
 329  * management necessary.
 330  *
 331  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 332  * _mesa_update_buffer_bounds(),
 333  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 334  */
 335 void
 336 _mesa_update_state_locked( struct gl_context *ctx )
 337 {
 338    GLbitfield new_state = ctx->NewState;
 339    GLbitfield prog_flags = _NEW_PROGRAM;
 340    GLbitfield new_prog_state = 0x0;
 341
 342    if (new_state == _NEW_CURRENT_ATTRIB)
 343       goto out;
 344
 345    if (MESA_VERBOSE & VERBOSE_STATE)
 346       _mesa_print_state("_mesa_update_state", new_state);
 347
 348    /* Determine which state flags effect vertex/fragment program state */
 349    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 350       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 351                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 352                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 353                      _NEW_COLOR);
 354    }
 355    if (ctx->VertexProgram._MaintainTnlProgram) {
 356       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 357                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 358                      _NEW_FOG | _NEW_LIGHT |
 359                      _MESA_NEW_NEED_EYE_COORDS);
 360    }
 361
 362    /*
 363     * Now update derived state info
 364     */
 365
 366    if (new_state & prog_flags)
 367       update_program_enables( ctx );
 368
 369    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 370       _mesa_update_modelview_project( ctx, new_state );
 371
 372    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 373       _mesa_update_texture( ctx, new_state );
 374
 375    if (new_state & _NEW_BUFFERS)
 376       _mesa_update_framebuffer(ctx);
 377
 378    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 379       _mesa_update_draw_buffer_bounds( ctx );
 380
 381    if (new_state & _NEW_LIGHT)
 382       _mesa_update_lighting( ctx );
 383
 384    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 385       update_twoside( ctx );
 386
 387    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 388       _mesa_update_stencil( ctx );
 389
 390    if (new_state & _NEW_PIXEL)
 391       _mesa_update_pixel( ctx, new_state );
 392
 393    if (new_state & (_NEW_BUFFERS | _NEW_VIEWPORT))
 394       update_viewport_matrix(ctx);
 395
 396    if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
 397       update_multisample( ctx );
 398
 399    /* ctx->_NeedEyeCoords is now up to date.
 400     *
 401     * If the truth value of this variable has changed, update for the
 402     * new lighting space and recompute the positions of lights and the
 403     * normal transform.
 404     *
 405     * If the lighting space hasn't changed, may still need to recompute
 406     * light positions & normal transforms for other reasons.
 407     */
 408    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 409       _mesa_update_tnl_spaces( ctx, new_state );
 410
 411    if (new_state & prog_flags) {
 412       /* When we generate programs from fixed-function vertex/fragment state
 413        * this call may generate/bind a new program.  If so, we need to
 414        * propogate the _NEW_PROGRAM flag to the driver.
 415        */
 416       new_prog_state |= update_program( ctx );
 417    }
 418
 419    if (new_state & _NEW_ARRAY)
 420       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 421
 422    if (ctx->Const.CheckArrayBounds &&
 423        new_state & (_NEW_ARRAY | _NEW_PROGRAM | _NEW_BUFFER_OBJECT)) {
 424       _mesa_update_vao_max_element(ctx, ctx->Array.VAO);
 425    }
 426
 427  out:
 428    new_prog_state |= update_program_constants(ctx);
 429
 430    /*
 431     * Give the driver a chance to act upon the new_state flags.
 432     * The driver might plug in different span functions, for example.
 433     * Also, this is where the driver can invalidate the state of any
 434     * active modules (such as swrast_setup, swrast, tnl, etc).
 435     *
 436     * Set ctx->NewState to zero to avoid recursion if
 437     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 438     */
 439    new_state = ctx->NewState | new_prog_state;
 440    ctx->NewState = 0;
 441    ctx->Driver.UpdateState(ctx, new_state);
 442    ctx->Array.VAO->NewArrays = 0x0;
 443 }
 444
 445
 446 /* This is the usual entrypoint for state updates:
 447  */
 448 void
 449 _mesa_update_state( struct gl_context *ctx )
 450 {
 451    _mesa_lock_context_textures(ctx);
 452    _mesa_update_state_locked(ctx);
 453    _mesa_unlock_context_textures(ctx);
 454 }
 455
 456
 457
 458
 459 /**
 460  * Want to figure out which fragment program inputs are actually
 461  * constant/current values from ctx->Current.  These should be
 462  * referenced as a tracked state variable rather than a fragment
 463  * program input, to save the overhead of putting a constant value in
 464  * every submitted vertex, transferring it to hardware, interpolating
 465  * it across the triangle, etc...
 466  *
 467  * When there is a VP bound, just use vp->outputs.  But when we're
 468  * generating vp from fixed function state, basically want to
 469  * calculate:
 470  *
 471  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 472  *                 potential_vp_outputs )
 473  *
 474  * Where potential_vp_outputs is calculated by looking at enabled
 475  * texgen, etc.
 476  *
 477  * The generated fragment program should then only declare inputs that
 478  * may vary or otherwise differ from the ctx->Current values.
 479  * Otherwise, the fp should track them as state values instead.
 480  */
 481 void
 482 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 483                              GLbitfield64 varying_inputs )
 484 {
 485    if (ctx->varying_vp_inputs != varying_inputs) {
 486       ctx->varying_vp_inputs = varying_inputs;
 487
 488       /* Only the fixed-func generated programs need to use the flag
 489        * and the fixed-func fragment program uses it only if there is also
 490        * a fixed-func vertex program, so this only depends on the latter.
 491        *
 492        * It's okay to check the VP pointer here, because this is called after
 493        * _mesa_update_state in the vbo module. */
 494       if (ctx->VertexProgram._TnlProgram ||
 495           ctx->FragmentProgram._TexEnvProgram) {
 496          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 497       }
 498       /*printf("%s %x\n", __FUNCTION__, varying_inputs);*/
 499    }
 500 }
 501
 502
 503 /**
 504  * Used by drivers to tell core Mesa that the driver is going to
 505  * install/ use its own vertex program.  In particular, this will
 506  * prevent generated fragment programs from using state vars instead
 507  * of ordinary varyings/inputs.
 508  */
 509 void
 510 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 511 {
 512    if (ctx->VertexProgram._Overriden != flag) {
 513       ctx->VertexProgram._Overriden = flag;
 514
 515       /* Set one of the bits which will trigger fragment program
 516        * regeneration:
 517        */
 518       ctx->NewState |= _NEW_PROGRAM;
 519    }
 520 }