src/mesa/main/state.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.3
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26
  27 /**
  28  * \file state.c
  29  * State management.
  30  *
  31  * This file manages recalculation of derived values in struct gl_context.
  32  */
  33
  34
  35 #include "glheader.h"
  36 #include "mtypes.h"
  37 #include "arrayobj.h"
  38 #include "context.h"
  39 #include "debug.h"
  40 #include "macros.h"
  41 #include "ffvertex_prog.h"
  42 #include "framebuffer.h"
  43 #include "light.h"
  44 #include "matrix.h"
  45 #include "pixel.h"
  46 #include "program/program.h"
  47 #include "program/prog_parameter.h"
  48 #include "shaderobj.h"
  49 #include "state.h"
  50 #include "stencil.h"
  51 #include "texenvprogram.h"
  52 #include "texobj.h"
  53 #include "texstate.h"
  54 #include "varray.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 = ctx->Shader.CurrentVertexProgram;
  99    const struct gl_shader_program *gsProg = ctx->Shader.CurrentGeometryProgram;
 100    struct gl_shader_program *fsProg = ctx->Shader.CurrentFragmentProgram;
 101    const struct gl_vertex_program *prevVP = ctx->VertexProgram._Current;
 102    const struct gl_fragment_program *prevFP = ctx->FragmentProgram._Current;
 103    const struct gl_geometry_program *prevGP = ctx->GeometryProgram._Current;
 104    GLbitfield new_state = 0x0;
 105
 106    /*
 107     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 108     * pointers to the programs that should be used for rendering.  If either
 109     * is NULL, use fixed-function code paths.
 110     *
 111     * These programs may come from several sources.  The priority is as
 112     * follows:
 113     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 114     *   2. ARB/NV vertex/fragment programs
 115     *   3. Programs derived from fixed-function state.
 116     *
 117     * Note: it's possible for a vertex shader to get used with a fragment
 118     * program (and vice versa) here, but in practice that shouldn't ever
 119     * come up, or matter.
 120     */
 121
 122    if (fsProg && fsProg->LinkStatus
 123        && fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]) {
 124       /* Use GLSL fragment shader */
 125       _mesa_reference_shader_program(ctx,
 126                                      &ctx->Shader._CurrentFragmentProgram,
 127                                      fsProg);
 128       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 129                                gl_fragment_program(fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 130       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 131                                NULL);
 132    }
 133    else if (ctx->FragmentProgram._Enabled) {
 134       /* Use user-defined fragment program */
 135       _mesa_reference_shader_program(ctx,
 136                                      &ctx->Shader._CurrentFragmentProgram,
 137                                      NULL);
 138       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 139                                ctx->FragmentProgram.Current);
 140       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 141                                NULL);
 142    }
 143    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 144       /* Use fragment program generated from fixed-function state */
 145       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 146
 147       _mesa_reference_shader_program(ctx,
 148                                      &ctx->Shader._CurrentFragmentProgram,
 149                                      f);
 150       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 151                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 152       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 153                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 154    }
 155    else {
 156       /* No fragment program */
 157       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 158       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 159                                NULL);
 160    }
 161
 162    if (gsProg && gsProg->LinkStatus
 163        && gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]) {
 164       /* Use GLSL geometry shader */
 165       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current,
 166                                gl_geometry_program(gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]->Program));
 167    } else {
 168       /* No geometry program */
 169       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current, NULL);
 170    }
 171
 172    /* Examine vertex program after fragment program as
 173     * _mesa_get_fixed_func_vertex_program() needs to know active
 174     * fragprog inputs.
 175     */
 176    if (vsProg && vsProg->LinkStatus
 177        && vsProg->_LinkedShaders[MESA_SHADER_VERTEX]) {
 178       /* Use GLSL vertex shader */
 179       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 180                                gl_vertex_program(vsProg->_LinkedShaders[MESA_SHADER_VERTEX]->Program));
 181    }
 182    else if (ctx->VertexProgram._Enabled) {
 183       /* Use user-defined vertex program */
 184       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 185                                ctx->VertexProgram.Current);
 186    }
 187    else if (ctx->VertexProgram._MaintainTnlProgram) {
 188       /* Use vertex program generated from fixed-function state */
 189       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 190                                _mesa_get_fixed_func_vertex_program(ctx));
 191       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram,
 192                                ctx->VertexProgram._Current);
 193    }
 194    else {
 195       /* no vertex program */
 196       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 197    }
 198
 199    /* Let the driver know what's happening:
 200     */
 201    if (ctx->FragmentProgram._Current != prevFP) {
 202       new_state |= _NEW_PROGRAM;
 203       if (ctx->Driver.BindProgram) {
 204          ctx->Driver.BindProgram(ctx, GL_FRAGMENT_PROGRAM_ARB,
 205                           (struct gl_program *) ctx->FragmentProgram._Current);
 206       }
 207    }
 208
 209    if (ctx->GeometryProgram._Current != prevGP) {
 210       new_state |= _NEW_PROGRAM;
 211       if (ctx->Driver.BindProgram) {
 212          ctx->Driver.BindProgram(ctx, MESA_GEOMETRY_PROGRAM,
 213                             (struct gl_program *) ctx->GeometryProgram._Current);
 214       }
 215    }
 216
 217    if (ctx->VertexProgram._Current != prevVP) {
 218       new_state |= _NEW_PROGRAM;
 219       if (ctx->Driver.BindProgram) {
 220          ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
 221                             (struct gl_program *) ctx->VertexProgram._Current);
 222       }
 223    }
 224
 225    return new_state;
 226 }
 227
 228
 229 /**
 230  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 231  */
 232 static GLbitfield
 233 update_program_constants(struct gl_context *ctx)
 234 {
 235    GLbitfield new_state = 0x0;
 236
 237    if (ctx->FragmentProgram._Current) {
 238       const struct gl_program_parameter_list *params =
 239          ctx->FragmentProgram._Current->Base.Parameters;
 240       if (params && params->StateFlags & ctx->NewState) {
 241          new_state |= _NEW_PROGRAM_CONSTANTS;
 242       }
 243    }
 244
 245    if (ctx->GeometryProgram._Current) {
 246       const struct gl_program_parameter_list *params =
 247          ctx->GeometryProgram._Current->Base.Parameters;
 248       /*FIXME: StateFlags is always 0 because we have unnamed constant
 249        *       not state changes */
 250       if (params /*&& params->StateFlags & ctx->NewState*/) {
 251          new_state |= _NEW_PROGRAM_CONSTANTS;
 252       }
 253    }
 254
 255    if (ctx->VertexProgram._Current) {
 256       const struct gl_program_parameter_list *params =
 257          ctx->VertexProgram._Current->Base.Parameters;
 258       if (params && params->StateFlags & ctx->NewState) {
 259          new_state |= _NEW_PROGRAM_CONSTANTS;
 260       }
 261    }
 262
 263    return new_state;
 264 }
 265
 266
 267
 268
 269 static void
 270 update_viewport_matrix(struct gl_context *ctx)
 271 {
 272    const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
 273
 274    ASSERT(depthMax > 0);
 275
 276    /* Compute scale and bias values. This is really driver-specific
 277     * and should be maintained elsewhere if at all.
 278     * NOTE: RasterPos uses this.
 279     */
 280    _math_matrix_viewport(&ctx->Viewport._WindowMap,
 281                          ctx->Viewport.X, ctx->Viewport.Y,
 282                          ctx->Viewport.Width, ctx->Viewport.Height,
 283                          ctx->Viewport.Near, ctx->Viewport.Far,
 284                          depthMax);
 285 }
 286
 287
 288 /**
 289  * Update derived multisample state.
 290  */
 291 static void
 292 update_multisample(struct gl_context *ctx)
 293 {
 294    ctx->Multisample._Enabled = GL_FALSE;
 295    if (ctx->Multisample.Enabled &&
 296        ctx->DrawBuffer &&
 297        ctx->DrawBuffer->Visual.sampleBuffers)
 298       ctx->Multisample._Enabled = GL_TRUE;
 299 }
 300
 301
 302 /**
 303  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 304  */
 305 static void
 306 update_twoside(struct gl_context *ctx)
 307 {
 308    if (ctx->Shader.CurrentVertexProgram ||
 309        ctx->VertexProgram._Enabled) {
 310       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 311    } else {
 312       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 313                                             ctx->Light.Model.TwoSide);
 314    }
 315 }
 316
 317
 318 /**
 319  * Compute derived GL state.
 320  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 321  * be called before rendering anything.
 322  *
 323  * Calls dd_function_table::UpdateState to perform any internal state
 324  * management necessary.
 325  *
 326  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 327  * _mesa_update_buffer_bounds(),
 328  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 329  */
 330 void
 331 _mesa_update_state_locked( struct gl_context *ctx )
 332 {
 333    GLbitfield new_state = ctx->NewState;
 334    GLbitfield prog_flags = _NEW_PROGRAM;
 335    GLbitfield new_prog_state = 0x0;
 336
 337    if (new_state == _NEW_CURRENT_ATTRIB)
 338       goto out;
 339
 340    if (MESA_VERBOSE & VERBOSE_STATE)
 341       _mesa_print_state("_mesa_update_state", new_state);
 342
 343    /* Determine which state flags effect vertex/fragment program state */
 344    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 345       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 346                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 347                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 348                      _NEW_COLOR);
 349    }
 350    if (ctx->VertexProgram._MaintainTnlProgram) {
 351       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 352                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 353                      _NEW_FOG | _NEW_LIGHT |
 354                      _MESA_NEW_NEED_EYE_COORDS);
 355    }
 356
 357    /*
 358     * Now update derived state info
 359     */
 360
 361    if (new_state & prog_flags)
 362       update_program_enables( ctx );
 363
 364    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 365       _mesa_update_modelview_project( ctx, new_state );
 366
 367    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 368       _mesa_update_texture( ctx, new_state );
 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_BUFFERS | _NEW_VIEWPORT))
 389       update_viewport_matrix(ctx);
 390
 391    if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
 392       update_multisample( ctx );
 393
 394    /* ctx->_NeedEyeCoords is now up to date.
 395     *
 396     * If the truth value of this variable has changed, update for the
 397     * new lighting space and recompute the positions of lights and the
 398     * normal transform.
 399     *
 400     * If the lighting space hasn't changed, may still need to recompute
 401     * light positions & normal transforms for other reasons.
 402     */
 403    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 404       _mesa_update_tnl_spaces( ctx, new_state );
 405
 406    if (new_state & prog_flags) {
 407       /* When we generate programs from fixed-function vertex/fragment state
 408        * this call may generate/bind a new program.  If so, we need to
 409        * propogate the _NEW_PROGRAM flag to the driver.
 410        */
 411       new_prog_state |= update_program( ctx );
 412    }
 413
 414    if (new_state & (_NEW_ARRAY | _NEW_PROGRAM | _NEW_BUFFER_OBJECT))
 415       _mesa_update_array_object_max_element(ctx, ctx->Array.ArrayObj);
 416
 417  out:
 418    new_prog_state |= update_program_constants(ctx);
 419
 420    /*
 421     * Give the driver a chance to act upon the new_state flags.
 422     * The driver might plug in different span functions, for example.
 423     * Also, this is where the driver can invalidate the state of any
 424     * active modules (such as swrast_setup, swrast, tnl, etc).
 425     *
 426     * Set ctx->NewState to zero to avoid recursion if
 427     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 428     */
 429    new_state = ctx->NewState | new_prog_state;
 430    ctx->NewState = 0;
 431    ctx->Driver.UpdateState(ctx, new_state);
 432 }
 433
 434
 435 /* This is the usual entrypoint for state updates:
 436  */
 437 void
 438 _mesa_update_state( struct gl_context *ctx )
 439 {
 440    _mesa_lock_context_textures(ctx);
 441    _mesa_update_state_locked(ctx);
 442    _mesa_unlock_context_textures(ctx);
 443 }
 444
 445
 446
 447
 448 /**
 449  * Want to figure out which fragment program inputs are actually
 450  * constant/current values from ctx->Current.  These should be
 451  * referenced as a tracked state variable rather than a fragment
 452  * program input, to save the overhead of putting a constant value in
 453  * every submitted vertex, transferring it to hardware, interpolating
 454  * it across the triangle, etc...
 455  *
 456  * When there is a VP bound, just use vp->outputs.  But when we're
 457  * generating vp from fixed function state, basically want to
 458  * calculate:
 459  *
 460  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 461  *                 potential_vp_outputs )
 462  *
 463  * Where potential_vp_outputs is calculated by looking at enabled
 464  * texgen, etc.
 465  *
 466  * The generated fragment program should then only declare inputs that
 467  * may vary or otherwise differ from the ctx->Current values.
 468  * Otherwise, the fp should track them as state values instead.
 469  */
 470 void
 471 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 472                              GLbitfield64 varying_inputs )
 473 {
 474    if (ctx->varying_vp_inputs != varying_inputs) {
 475       ctx->varying_vp_inputs = varying_inputs;
 476
 477       /* Only the fixed-func generated programs need to use the flag
 478        * and the fixed-func fragment program uses it only if there is also
 479        * a fixed-func vertex program, so this only depends on the latter.
 480        *
 481        * It's okay to check the VP pointer here, because this is called after
 482        * _mesa_update_state in the vbo module. */
 483       if (ctx->VertexProgram._TnlProgram ||
 484           ctx->FragmentProgram._TexEnvProgram) {
 485          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 486       }
 487       /*printf("%s %x\n", __FUNCTION__, varying_inputs);*/
 488    }
 489 }
 490
 491
 492 /**
 493  * Used by drivers to tell core Mesa that the driver is going to
 494  * install/ use its own vertex program.  In particular, this will
 495  * prevent generated fragment programs from using state vars instead
 496  * of ordinary varyings/inputs.
 497  */
 498 void
 499 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 500 {
 501    if (ctx->VertexProgram._Overriden != flag) {
 502       ctx->VertexProgram._Overriden = flag;
 503
 504       /* Set one of the bits which will trigger fragment program
 505        * regeneration:
 506        */
 507       ctx->NewState |= _NEW_PROGRAM;
 508    }
 509 }