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