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 BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR 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 = ctx->Shader.CurrentVertexProgram;
  98    const struct gl_shader_program *gsProg = ctx->Shader.CurrentGeometryProgram;
  99    struct gl_shader_program *fsProg = ctx->Shader.CurrentFragmentProgram;
 100    const struct gl_vertex_program *prevVP = ctx->VertexProgram._Current;
 101    const struct gl_fragment_program *prevFP = ctx->FragmentProgram._Current;
 102    const struct gl_geometry_program *prevGP = ctx->GeometryProgram._Current;
 103    GLbitfield new_state = 0x0;
 104
 105    /*
 106     * Set the ctx->VertexProgram._Current and ctx->FragmentProgram._Current
 107     * pointers to the programs that should be used for rendering.  If either
 108     * is NULL, use fixed-function code paths.
 109     *
 110     * These programs may come from several sources.  The priority is as
 111     * follows:
 112     *   1. OpenGL 2.0/ARB vertex/fragment shaders
 113     *   2. ARB/NV vertex/fragment programs
 114     *   3. Programs derived from fixed-function state.
 115     *
 116     * Note: it's possible for a vertex shader to get used with a fragment
 117     * program (and vice versa) here, but in practice that shouldn't ever
 118     * come up, or matter.
 119     */
 120
 121    if (fsProg && fsProg->LinkStatus
 122        && fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]) {
 123       /* Use GLSL fragment shader */
 124       _mesa_reference_shader_program(ctx,
 125                                      &ctx->Shader._CurrentFragmentProgram,
 126                                      fsProg);
 127       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 128                                gl_fragment_program(fsProg->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 129       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 130                                NULL);
 131    }
 132    else if (ctx->FragmentProgram._Enabled) {
 133       /* Use user-defined fragment program */
 134       _mesa_reference_shader_program(ctx,
 135                                      &ctx->Shader._CurrentFragmentProgram,
 136                                      NULL);
 137       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 138                                ctx->FragmentProgram.Current);
 139       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 140                                NULL);
 141    }
 142    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 143       /* Use fragment program generated from fixed-function state */
 144       struct gl_shader_program *f = _mesa_get_fixed_func_fragment_program(ctx);
 145
 146       _mesa_reference_shader_program(ctx,
 147                                      &ctx->Shader._CurrentFragmentProgram,
 148                                      f);
 149       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
 150                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 151       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 152                                gl_fragment_program(f->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program));
 153    }
 154    else {
 155       /* No fragment program */
 156       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 157       _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
 158                                NULL);
 159    }
 160
 161    if (gsProg && gsProg->LinkStatus
 162        && gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]) {
 163       /* Use GLSL geometry shader */
 164       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current,
 165                                gl_geometry_program(gsProg->_LinkedShaders[MESA_SHADER_GEOMETRY]->Program));
 166    } else {
 167       /* No geometry program */
 168       _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current, NULL);
 169    }
 170
 171    /* Examine vertex program after fragment program as
 172     * _mesa_get_fixed_func_vertex_program() needs to know active
 173     * fragprog inputs.
 174     */
 175    if (vsProg && vsProg->LinkStatus
 176        && vsProg->_LinkedShaders[MESA_SHADER_VERTEX]) {
 177       /* Use GLSL vertex shader */
 178       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 179                                gl_vertex_program(vsProg->_LinkedShaders[MESA_SHADER_VERTEX]->Program));
 180    }
 181    else if (ctx->VertexProgram._Enabled) {
 182       /* Use user-defined vertex program */
 183       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 184                                ctx->VertexProgram.Current);
 185    }
 186    else if (ctx->VertexProgram._MaintainTnlProgram) {
 187       /* Use vertex program generated from fixed-function state */
 188       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
 189                                _mesa_get_fixed_func_vertex_program(ctx));
 190       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram,
 191                                ctx->VertexProgram._Current);
 192    }
 193    else {
 194       /* no vertex program */
 195       _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 196    }
 197
 198    /* Let the driver know what's happening:
 199     */
 200    if (ctx->FragmentProgram._Current != prevFP) {
 201       new_state |= _NEW_PROGRAM;
 202       if (ctx->Driver.BindProgram) {
 203          ctx->Driver.BindProgram(ctx, GL_FRAGMENT_PROGRAM_ARB,
 204                           (struct gl_program *) ctx->FragmentProgram._Current);
 205       }
 206    }
 207
 208    if (ctx->GeometryProgram._Current != prevGP) {
 209       new_state |= _NEW_PROGRAM;
 210       if (ctx->Driver.BindProgram) {
 211          ctx->Driver.BindProgram(ctx, MESA_GEOMETRY_PROGRAM,
 212                             (struct gl_program *) ctx->GeometryProgram._Current);
 213       }
 214    }
 215
 216    if (ctx->VertexProgram._Current != prevVP) {
 217       new_state |= _NEW_PROGRAM;
 218       if (ctx->Driver.BindProgram) {
 219          ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
 220                             (struct gl_program *) ctx->VertexProgram._Current);
 221       }
 222    }
 223
 224    return new_state;
 225 }
 226
 227
 228 /**
 229  * Examine shader constants and return either _NEW_PROGRAM_CONSTANTS or 0.
 230  */
 231 static GLbitfield
 232 update_program_constants(struct gl_context *ctx)
 233 {
 234    GLbitfield new_state = 0x0;
 235
 236    if (ctx->FragmentProgram._Current) {
 237       const struct gl_program_parameter_list *params =
 238          ctx->FragmentProgram._Current->Base.Parameters;
 239       if (params && params->StateFlags & ctx->NewState) {
 240          new_state |= _NEW_PROGRAM_CONSTANTS;
 241       }
 242    }
 243
 244    if (ctx->GeometryProgram._Current) {
 245       const struct gl_program_parameter_list *params =
 246          ctx->GeometryProgram._Current->Base.Parameters;
 247       /*FIXME: StateFlags is always 0 because we have unnamed constant
 248        *       not state changes */
 249       if (params /*&& params->StateFlags & ctx->NewState*/) {
 250          new_state |= _NEW_PROGRAM_CONSTANTS;
 251       }
 252    }
 253
 254    if (ctx->VertexProgram._Current) {
 255       const struct gl_program_parameter_list *params =
 256          ctx->VertexProgram._Current->Base.Parameters;
 257       if (params && params->StateFlags & ctx->NewState) {
 258          new_state |= _NEW_PROGRAM_CONSTANTS;
 259       }
 260    }
 261
 262    return new_state;
 263 }
 264
 265
 266
 267
 268 static void
 269 update_viewport_matrix(struct gl_context *ctx)
 270 {
 271    const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
 272
 273    ASSERT(depthMax > 0);
 274
 275    /* Compute scale and bias values. This is really driver-specific
 276     * and should be maintained elsewhere if at all.
 277     * NOTE: RasterPos uses this.
 278     */
 279    _math_matrix_viewport(&ctx->Viewport._WindowMap,
 280                          ctx->Viewport.X, ctx->Viewport.Y,
 281                          ctx->Viewport.Width, ctx->Viewport.Height,
 282                          ctx->Viewport.Near, ctx->Viewport.Far,
 283                          depthMax);
 284 }
 285
 286
 287 /**
 288  * Update derived multisample state.
 289  */
 290 static void
 291 update_multisample(struct gl_context *ctx)
 292 {
 293    ctx->Multisample._Enabled = GL_FALSE;
 294    if (ctx->Multisample.Enabled &&
 295        ctx->DrawBuffer &&
 296        ctx->DrawBuffer->Visual.sampleBuffers)
 297       ctx->Multisample._Enabled = GL_TRUE;
 298 }
 299
 300
 301 /**
 302  * Update the ctx->VertexProgram._TwoSideEnabled flag.
 303  */
 304 static void
 305 update_twoside(struct gl_context *ctx)
 306 {
 307    if (ctx->Shader.CurrentVertexProgram ||
 308        ctx->VertexProgram._Enabled) {
 309       ctx->VertexProgram._TwoSideEnabled = ctx->VertexProgram.TwoSideEnabled;
 310    } else {
 311       ctx->VertexProgram._TwoSideEnabled = (ctx->Light.Enabled &&
 312                                             ctx->Light.Model.TwoSide);
 313    }
 314 }
 315
 316
 317 /**
 318  * Compute derived GL state.
 319  * If __struct gl_contextRec::NewState is non-zero then this function \b must
 320  * be called before rendering anything.
 321  *
 322  * Calls dd_function_table::UpdateState to perform any internal state
 323  * management necessary.
 324  *
 325  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
 326  * _mesa_update_buffer_bounds(),
 327  * _mesa_update_lighting() and _mesa_update_tnl_spaces().
 328  */
 329 void
 330 _mesa_update_state_locked( struct gl_context *ctx )
 331 {
 332    GLbitfield new_state = ctx->NewState;
 333    GLbitfield prog_flags = _NEW_PROGRAM;
 334    GLbitfield new_prog_state = 0x0;
 335
 336    if (new_state == _NEW_CURRENT_ATTRIB)
 337       goto out;
 338
 339    if (MESA_VERBOSE & VERBOSE_STATE)
 340       _mesa_print_state("_mesa_update_state", new_state);
 341
 342    /* Determine which state flags effect vertex/fragment program state */
 343    if (ctx->FragmentProgram._MaintainTexEnvProgram) {
 344       prog_flags |= (_NEW_BUFFERS | _NEW_TEXTURE | _NEW_FOG |
 345                      _NEW_VARYING_VP_INPUTS | _NEW_LIGHT | _NEW_POINT |
 346                      _NEW_RENDERMODE | _NEW_PROGRAM | _NEW_FRAG_CLAMP |
 347                      _NEW_COLOR);
 348    }
 349    if (ctx->VertexProgram._MaintainTnlProgram) {
 350       prog_flags |= (_NEW_VARYING_VP_INPUTS | _NEW_TEXTURE |
 351                      _NEW_TEXTURE_MATRIX | _NEW_TRANSFORM | _NEW_POINT |
 352                      _NEW_FOG | _NEW_LIGHT |
 353                      _MESA_NEW_NEED_EYE_COORDS);
 354    }
 355
 356    /*
 357     * Now update derived state info
 358     */
 359
 360    if (new_state & prog_flags)
 361       update_program_enables( ctx );
 362
 363    if (new_state & (_NEW_MODELVIEW|_NEW_PROJECTION))
 364       _mesa_update_modelview_project( ctx, new_state );
 365
 366    if (new_state & (_NEW_PROGRAM|_NEW_TEXTURE|_NEW_TEXTURE_MATRIX))
 367       _mesa_update_texture( ctx, new_state );
 368
 369    if (new_state & _NEW_BUFFERS)
 370       _mesa_update_framebuffer(ctx);
 371
 372    if (new_state & (_NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT))
 373       _mesa_update_draw_buffer_bounds( ctx );
 374
 375    if (new_state & _NEW_LIGHT)
 376       _mesa_update_lighting( ctx );
 377
 378    if (new_state & (_NEW_LIGHT | _NEW_PROGRAM))
 379       update_twoside( ctx );
 380
 381    if (new_state & (_NEW_STENCIL | _NEW_BUFFERS))
 382       _mesa_update_stencil( ctx );
 383
 384    if (new_state & _NEW_PIXEL)
 385       _mesa_update_pixel( ctx, new_state );
 386
 387    if (new_state & (_NEW_BUFFERS | _NEW_VIEWPORT))
 388       update_viewport_matrix(ctx);
 389
 390    if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
 391       update_multisample( ctx );
 392
 393    /* ctx->_NeedEyeCoords is now up to date.
 394     *
 395     * If the truth value of this variable has changed, update for the
 396     * new lighting space and recompute the positions of lights and the
 397     * normal transform.
 398     *
 399     * If the lighting space hasn't changed, may still need to recompute
 400     * light positions & normal transforms for other reasons.
 401     */
 402    if (new_state & _MESA_NEW_NEED_EYE_COORDS)
 403       _mesa_update_tnl_spaces( ctx, new_state );
 404
 405    if (new_state & prog_flags) {
 406       /* When we generate programs from fixed-function vertex/fragment state
 407        * this call may generate/bind a new program.  If so, we need to
 408        * propogate the _NEW_PROGRAM flag to the driver.
 409        */
 410       new_prog_state |= update_program( ctx );
 411    }
 412
 413    if (new_state & (_NEW_ARRAY | _NEW_PROGRAM | _NEW_BUFFER_OBJECT))
 414       _mesa_update_array_object_max_element(ctx, ctx->Array.ArrayObj);
 415
 416  out:
 417    new_prog_state |= update_program_constants(ctx);
 418
 419    /*
 420     * Give the driver a chance to act upon the new_state flags.
 421     * The driver might plug in different span functions, for example.
 422     * Also, this is where the driver can invalidate the state of any
 423     * active modules (such as swrast_setup, swrast, tnl, etc).
 424     *
 425     * Set ctx->NewState to zero to avoid recursion if
 426     * Driver.UpdateState() has to call FLUSH_VERTICES().  (fixed?)
 427     */
 428    new_state = ctx->NewState | new_prog_state;
 429    ctx->NewState = 0;
 430    ctx->Driver.UpdateState(ctx, new_state);
 431    ctx->Array.ArrayObj->NewArrays = 0x0;
 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 }