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 static void
 273 update_viewport_matrix(struct gl_context *ctx)
 274 {
 275    const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
 276    unsigned i;
 277
 278    ASSERT(depthMax > 0);
 279
 280    /* Compute scale and bias values. This is really driver-specific
 281     * and should be maintained elsewhere if at all.
 282     * NOTE: RasterPos uses this.
 283     */
 284    for (i = 0; i < ctx->Const.MaxViewports; i++) {
 285       double scale[3], translate[3];
 286
 287       _mesa_get_viewport_xform(ctx, i, scale, translate);
 288       _math_matrix_viewport(&ctx->ViewportArray[i]._WindowMap,
 289                             scale, translate, depthMax);
 290    }
 291 }
 292
 293
 294 /**
 295  * Update the ctx->Polygon._FrontBit flag.
 296  */
 297 static void
 298 update_frontbit(struct gl_context *ctx)
 299 {
 300    if (ctx->Transform.ClipOrigin == GL_LOWER_LEFT)
 301       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CW);
 302    else
 303       ctx->Polygon._FrontBit = (ctx->Polygon.FrontFace == GL_CCW);
 304 }
 305
 306
 307 /**
 308  * Update derived multisample state.
 309  */
 310 static void
 311 update_multisample(struct gl_context *ctx)
 312 {
 313    ctx->Multisample._Enabled = GL_FALSE;
 314    if (ctx->Multisample.Enabled &&
 315        ctx->DrawBuffer &&
 316        ctx->DrawBuffer->Visual.sampleBuffers)
 317       ctx->Multisample._Enabled = GL_TRUE;
 318 }
 319
 320
 321 /**
 322  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 323  */
 324 static void
 325 update_twoside(struct gl_context *ctx)
 326 {
 327    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX] ||
 328        ctx->VertexProgram._Enabled) {
 329       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 330    } else {
 331       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 332                                             ctx->Light.Model.TwoSide);
 333    }
 334 }
 335
 336
 337 /**
 338  * Compute derived GL state.
 339  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 340  * be called before rendering anything.
 341  *
 342  * Calls dd_function_table::UpdateState to perform any internal state
 343  * management necessary.
 344  *
 345  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 346  * _mesa_update_buffer_bounds(),
 347  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 348  */
 349 void
 350 _mesa_update_state_locked( struct gl_context *ctx )
 351 {
 352    GLbitfield new_state = ctx->NewState;
 353    GLbitfield prog_flags = _NEW_PROGRAM;
 354    GLbitfield new_prog_state = 0x0;
 355
 356    if (new_state == _NEW_CURRENT_ATTRIB)
 357       goto out;
 358
 359    if (MESA_VERBOSE & VERBOSE_STATE)
 360       _mesa_print_state("_mesa_update_state", new_state);
 361
 362    /* Determine which state flags effect vertex/fragment program state */
 363    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 364       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 365                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 366                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 367                      _NEW_COLOR);
 368    }
 369    if (ctx->VertexProgram._MaintainTnlProgram) {
 370       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 371                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 372                      _NEW_FOG | _NEW_LIGHT |
 373                      _MESA_NEW_NEED_EYE_COORDS);
 374    }
 375
 376    /*
 377     * Now update derived state info
 378     */
 379
 380    if (new_state & prog_flags)
 381       update_program_enables( ctx );
 382
 383    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 384       _mesa_update_modelview_project( ctx, new_state );
 385
 386    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 387       _mesa_update_texture( ctx, new_state );
 388
 389    if (new_state & _NEW_POLYGON)
 390       update_frontbit( ctx );
 391
 392    if (new_state & _NEW_BUFFERS)
 393       _mesa_update_framebuffer(ctx);
 394
 395    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 396       _mesa_update_draw_buffer_bounds( ctx );
 397
 398    if (new_state & _NEW_LIGHT)
 399       _mesa_update_lighting( ctx );
 400
 401    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 402       update_twoside( ctx );
 403
 404    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 405       _mesa_update_stencil( ctx );
 406
 407    if (new_state & _NEW_PIXEL)
 408       _mesa_update_pixel( ctx, new_state );
 409
 410    if (new_state & (_NEW_BUFFERS | _NEW_VIEWPORT))
 411       update_viewport_matrix(ctx);
 412
 413    if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
 414       update_multisample( ctx );
 415
 416    /* ctx->_NeedEyeCoords is now up to date.
 417     *
 418     * If the truth value of this variable has changed, update for the
 419     * new lighting space and recompute the positions of lights and the
 420     * normal transform.
 421     *
 422     * If the lighting space hasn't changed, may still need to recompute
 423     * light positions & normal transforms for other reasons.
 424     */
 425    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 426       _mesa_update_tnl_spaces( ctx, new_state );
 427
 428    if (new_state & prog_flags) {
 429       /* When we generate programs from fixed-function vertex/fragment state
 430        * this call may generate/bind a new program.  If so, we need to
 431        * propogate the _NEW_PROGRAM flag to the driver.
 432        */
 433       new_prog_state |= update_program( ctx );
 434    }
 435
 436    if (new_state & _NEW_ARRAY)
 437       _mesa_update_vao_client_arrays(ctx, ctx->Array.VAO);
 438
 439  out:
 440    new_prog_state |= update_program_constants(ctx);
 441
 442    /*
 443     * Give the driver a chance to act upon the new_state flags.
 444     * The driver might plug in different span functions, for example.
 445     * Also, this is where the driver can invalidate the state of any
 446     * active modules (such as swrast_setup, swrast, tnl, etc).
 447     *
 448     * Set ctx->NewState to zero to avoid recursion if
 449     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 450     */
 451    new_state = ctx->NewState | new_prog_state;
 452    ctx->NewState = 0;
 453    ctx->Driver.UpdateState(ctx, new_state);
 454    ctx->Array.VAO->NewArrays = 0x0;
 455 }
 456
 457
 458 /* This is the usual entrypoint for state updates:
 459  */
 460 void
 461 _mesa_update_state( struct gl_context *ctx )
 462 {
 463    _mesa_lock_context_textures(ctx);
 464    _mesa_update_state_locked(ctx);
 465    _mesa_unlock_context_textures(ctx);
 466 }
 467
 468
 469
 470
 471 /**
 472  * Want to figure out which fragment program inputs are actually
 473  * constant/current values from ctx->Current.  These should be
 474  * referenced as a tracked state variable rather than a fragment
 475  * program input, to save the overhead of putting a constant value in
 476  * every submitted vertex, transferring it to hardware, interpolating
 477  * it across the triangle, etc...
 478  *
 479  * When there is a VP bound, just use vp->outputs.  But when we're
 480  * generating vp from fixed function state, basically want to
 481  * calculate:
 482  *
 483  * vp_out_2_fp_in( vp_in_2_vp_out( varying_inputs ) |
 484  *                 potential_vp_outputs )
 485  *
 486  * Where potential_vp_outputs is calculated by looking at enabled
 487  * texgen, etc.
 488  *
 489  * The generated fragment program should then only declare inputs that
 490  * may vary or otherwise differ from the ctx->Current values.
 491  * Otherwise, the fp should track them as state values instead.
 492  */
 493 void
 494 _mesa_set_varying_vp_inputs( struct gl_context *ctx,
 495                              GLbitfield64 varying_inputs )
 496 {
 497    if (ctx->varying_vp_inputs != varying_inputs) {
 498       ctx->varying_vp_inputs = varying_inputs;
 499
 500       /* Only the fixed-func generated programs need to use the flag
 501        * and the fixed-func fragment program uses it only if there is also
 502        * a fixed-func vertex program, so this only depends on the latter.
 503        *
 504        * It's okay to check the VP pointer here, because this is called after
 505        * _mesa_update_state in the vbo module. */
 506       if (ctx->VertexProgram._TnlProgram ||
 507           ctx->FragmentProgram._TexEnvProgram) {
 508          ctx->NewState |= _NEW_VARYING_VP_INPUTS;
 509       }
 510       /*printf("%s %x\n", __FUNCTION__, varying_inputs);*/
 511    }
 512 }
 513
 514
 515 /**
 516  * Used by drivers to tell core Mesa that the driver is going to
 517  * install/ use its own vertex program.  In particular, this will
 518  * prevent generated fragment programs from using state vars instead
 519  * of ordinary varyings/inputs.
 520  */
 521 void
 522 _mesa_set_vp_override(struct gl_context *ctx, GLboolean flag)
 523 {
 524    if (ctx->VertexProgram._Overriden != flag) {
 525       ctx->VertexProgram._Overriden = flag;
 526
 527       /* Set one of the bits which will trigger fragment program
 528        * regeneration:
 529        */
 530       ctx->NewState |= _NEW_PROGRAM;
 531    }
 532 }