src/mesa/main/accum.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5
   4  *
   5  * Copyright (C) 1999-2005  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  * BRIAN PAUL 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 #include "glheader.h"
  26 #include "accum.h"
  27 #include "condrender.h"
  28 #include "context.h"
  29 #include "format_unpack.h"
  30 #include "format_pack.h"
  31 #include "imports.h"
  32 #include "macros.h"
  33 #include "mfeatures.h"
  34 #include "state.h"
  35 #include "mtypes.h"
  36 #include "main/dispatch.h"
  37
  38
  39 #if FEATURE_accum
  40
  41
  42 void GLAPIENTRY
  43 _mesa_ClearAccum( GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha )
  44 {
  45    GLfloat tmp[4];
  46    GET_CURRENT_CONTEXT(ctx);
  47    ASSERT_OUTSIDE_BEGIN_END(ctx);
  48
  49    tmp[0] = CLAMP( red,   -1.0F, 1.0F );
  50    tmp[1] = CLAMP( green, -1.0F, 1.0F );
  51    tmp[2] = CLAMP( blue,  -1.0F, 1.0F );
  52    tmp[3] = CLAMP( alpha, -1.0F, 1.0F );
  53
  54    if (TEST_EQ_4V(tmp, ctx->Accum.ClearColor))
  55       return;
  56
  57    COPY_4FV( ctx->Accum.ClearColor, tmp );
  58 }
  59
  60
  61 static void GLAPIENTRY
  62 _mesa_Accum( GLenum op, GLfloat value )
  63 {
  64    GET_CURRENT_CONTEXT(ctx);
  65    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
  66
  67    switch (op) {
  68    case GL_ADD:
  69    case GL_MULT:
  70    case GL_ACCUM:
  71    case GL_LOAD:
  72    case GL_RETURN:
  73       /* OK */
  74       break;
  75    default:
  76       _mesa_error(ctx, GL_INVALID_ENUM, "glAccum(op)");
  77       return;
  78    }
  79
  80    if (ctx->DrawBuffer->Visual.haveAccumBuffer == 0) {
  81       _mesa_error(ctx, GL_INVALID_OPERATION, "glAccum(no accum buffer)");
  82       return;
  83    }
  84
  85    if (ctx->DrawBuffer != ctx->ReadBuffer) {
  86       /* See GLX_SGI_make_current_read or WGL_ARB_make_current_read,
  87        * or GL_EXT_framebuffer_blit.
  88        */
  89       _mesa_error(ctx, GL_INVALID_OPERATION,
  90                   "glAccum(different read/draw buffers)");
  91       return;
  92    }
  93
  94    if (ctx->NewState)
  95       _mesa_update_state(ctx);
  96
  97    if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
  98       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
  99                   "glAccum(incomplete framebuffer)");
 100       return;
 101    }
 102
 103    if (ctx->RasterDiscard)
 104       return;
 105
 106    if (ctx->RenderMode == GL_RENDER) {
 107       _mesa_accum(ctx, op, value);
 108    }
 109 }
 110
 111
 112 void
 113 _mesa_init_accum_dispatch(struct _glapi_table *disp)
 114 {
 115    SET_Accum(disp, _mesa_Accum);
 116    SET_ClearAccum(disp, _mesa_ClearAccum);
 117 }
 118
 119
 120 /**
 121  * Clear the accumulation buffer by mapping the renderbuffer and
 122  * writing the clear color to it.  Called by the driver's implementation
 123  * of the glClear function.
 124  */
 125 void
 126 _mesa_clear_accum_buffer(struct gl_context *ctx)
 127 {
 128    GLuint x, y, width, height;
 129    GLubyte *accMap;
 130    GLint accRowStride;
 131    struct gl_renderbuffer *accRb;
 132
 133    if (!ctx->DrawBuffer)
 134       return;
 135
 136    accRb = ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer;
 137    if (!accRb)
 138       return;   /* missing accum buffer, not an error */
 139
 140    /* bounds, with scissor */
 141    x = ctx->DrawBuffer->_Xmin;
 142    y = ctx->DrawBuffer->_Ymin;
 143    width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
 144    height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
 145
 146    ctx->Driver.MapRenderbuffer(ctx, accRb, x, y, width, height,
 147                                GL_MAP_WRITE_BIT, &accMap, &accRowStride);
 148
 149    if (!accMap) {
 150       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 151       return;
 152    }
 153
 154    if (accRb->Format == MESA_FORMAT_SIGNED_RGBA_16) {
 155       const GLshort clearR = FLOAT_TO_SHORT(ctx->Accum.ClearColor[0]);
 156       const GLshort clearG = FLOAT_TO_SHORT(ctx->Accum.ClearColor[1]);
 157       const GLshort clearB = FLOAT_TO_SHORT(ctx->Accum.ClearColor[2]);
 158       const GLshort clearA = FLOAT_TO_SHORT(ctx->Accum.ClearColor[3]);
 159       GLuint i, j;
 160
 161       for (j = 0; j < height; j++) {
 162          GLshort *row = (GLshort *) accMap;
 163
 164          for (i = 0; i < width; i++) {
 165             row[i * 4 + 0] = clearR;
 166             row[i * 4 + 1] = clearG;
 167             row[i * 4 + 2] = clearB;
 168             row[i * 4 + 3] = clearA;
 169          }
 170          accMap += accRowStride;
 171       }
 172    }
 173    else {
 174       /* other types someday? */
 175       _mesa_warning(ctx, "unexpected accum buffer type");
 176    }
 177
 178    ctx->Driver.UnmapRenderbuffer(ctx, accRb);
 179 }
 180
 181
 182 /**
 183  * if (bias)
 184  *    Accum += value
 185  * else
 186  *    Accum *= value
 187  */
 188 static void
 189 accum_scale_or_bias(struct gl_context *ctx, GLfloat value,
 190                     GLint xpos, GLint ypos, GLint width, GLint height,
 191                     GLboolean bias)
 192 {
 193    struct gl_renderbuffer *accRb =
 194       ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer;
 195    GLubyte *accMap;
 196    GLint accRowStride;
 197
 198    assert(accRb);
 199
 200    ctx->Driver.MapRenderbuffer(ctx, accRb, xpos, ypos, width, height,
 201                                GL_MAP_READ_BIT | GL_MAP_WRITE_BIT,
 202                                &accMap, &accRowStride);
 203
 204    if (!accMap) {
 205       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 206       return;
 207    }
 208
 209    if (accRb->Format == MESA_FORMAT_SIGNED_RGBA_16) {
 210       const GLshort incr = (GLshort) (value * 32767.0f);
 211       GLuint i, j;
 212       if (bias) {
 213          for (j = 0; j < height; j++) {
 214             GLshort *acc = (GLshort *) accMap;
 215             for (i = 0; i < 4 * width; i++) {
 216                acc[i] += incr;
 217             }
 218             accMap += accRowStride;
 219          }
 220       }
 221       else {
 222          /* scale */
 223          for (j = 0; j < height; j++) {
 224             GLshort *acc = (GLshort *) accMap;
 225             for (i = 0; i < 4 * width; i++) {
 226                acc[i] = (GLshort) (acc[i] * value);
 227             }
 228             accMap += accRowStride;
 229          }
 230       }
 231    }
 232    else {
 233       /* other types someday? */
 234    }
 235
 236    ctx->Driver.UnmapRenderbuffer(ctx, accRb);
 237 }
 238
 239
 240 /**
 241  * if (load)
 242  *    Accum = ColorBuf * value
 243  * else
 244  *    Accum += ColorBuf * value
 245  */
 246 static void
 247 accum_or_load(struct gl_context *ctx, GLfloat value,
 248               GLint xpos, GLint ypos, GLint width, GLint height,
 249               GLboolean load)
 250 {
 251    struct gl_renderbuffer *accRb =
 252       ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer;
 253    struct gl_renderbuffer *colorRb = ctx->ReadBuffer->_ColorReadBuffer;
 254    GLubyte *accMap, *colorMap;
 255    GLint accRowStride, colorRowStride;
 256    GLbitfield mappingFlags;
 257
 258    if (!colorRb) {
 259       /* no read buffer - OK */
 260       return;
 261    }
 262
 263    assert(accRb);
 264
 265    mappingFlags = GL_MAP_WRITE_BIT;
 266    if (!load) /* if we're accumulating */
 267       mappingFlags |= GL_MAP_READ_BIT;
 268
 269    /* Map accum buffer */
 270    ctx->Driver.MapRenderbuffer(ctx, accRb, xpos, ypos, width, height,
 271                                mappingFlags, &accMap, &accRowStride);
 272    if (!accMap) {
 273       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 274       return;
 275    }
 276
 277    /* Map color buffer */
 278    ctx->Driver.MapRenderbuffer(ctx, colorRb, xpos, ypos, width, height,
 279                                GL_MAP_READ_BIT,
 280                                &colorMap, &colorRowStride);
 281    if (!colorMap) {
 282       ctx->Driver.UnmapRenderbuffer(ctx, accRb);
 283       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 284       return;
 285    }
 286
 287    if (accRb->Format == MESA_FORMAT_SIGNED_RGBA_16) {
 288       const GLfloat scale = value * 32767.0f;
 289       GLuint i, j;
 290       GLfloat (*rgba)[4];
 291
 292       rgba = (GLfloat (*)[4]) malloc(width * 4 * sizeof(GLfloat));
 293       if (rgba) {
 294          for (j = 0; j < height; j++) {
 295             GLshort *acc = (GLshort *) accMap;
 296
 297             /* read colors from source color buffer */
 298             _mesa_unpack_rgba_row(colorRb->Format, width, colorMap, rgba);
 299
 300             if (load) {
 301                for (i = 0; i < width; i++) {
 302                   acc[i * 4 + 0] = (GLshort) (rgba[i][RCOMP] * scale);
 303                   acc[i * 4 + 1] = (GLshort) (rgba[i][GCOMP] * scale);
 304                   acc[i * 4 + 2] = (GLshort) (rgba[i][BCOMP] * scale);
 305                   acc[i * 4 + 3] = (GLshort) (rgba[i][ACOMP] * scale);
 306                }
 307             }
 308             else {
 309                /* accumulate */
 310                for (i = 0; i < width; i++) {
 311                   acc[i * 4 + 0] += (GLshort) (rgba[i][RCOMP] * scale);
 312                   acc[i * 4 + 1] += (GLshort) (rgba[i][GCOMP] * scale);
 313                   acc[i * 4 + 2] += (GLshort) (rgba[i][BCOMP] * scale);
 314                   acc[i * 4 + 3] += (GLshort) (rgba[i][ACOMP] * scale);
 315                }
 316             }
 317
 318             colorMap += colorRowStride;
 319             accMap += accRowStride;
 320          }
 321
 322          free(rgba);
 323       }
 324       else {
 325          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 326       }
 327    }
 328    else {
 329       /* other types someday? */
 330    }
 331
 332    ctx->Driver.UnmapRenderbuffer(ctx, accRb);
 333    ctx->Driver.UnmapRenderbuffer(ctx, colorRb);
 334 }
 335
 336
 337 /**
 338  * ColorBuffer = Accum * value
 339  */
 340 static void
 341 accum_return(struct gl_context *ctx, GLfloat value,
 342              GLint xpos, GLint ypos, GLint width, GLint height)
 343 {
 344    struct gl_framebuffer *fb = ctx->DrawBuffer;
 345    struct gl_renderbuffer *accRb = fb->Attachment[BUFFER_ACCUM].Renderbuffer;
 346    GLubyte *accMap, *colorMap;
 347    GLint accRowStride, colorRowStride;
 348    GLuint buffer;
 349
 350    /* Map accum buffer */
 351    ctx->Driver.MapRenderbuffer(ctx, accRb, xpos, ypos, width, height,
 352                                GL_MAP_READ_BIT,
 353                                &accMap, &accRowStride);
 354    if (!accMap) {
 355       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 356       return;
 357    }
 358
 359    /* Loop over destination buffers */
 360    for (buffer = 0; buffer < fb->_NumColorDrawBuffers; buffer++) {
 361       struct gl_renderbuffer *colorRb = fb->_ColorDrawBuffers[buffer];
 362       const GLboolean masking = (!ctx->Color.ColorMask[buffer][RCOMP] ||
 363                                  !ctx->Color.ColorMask[buffer][GCOMP] ||
 364                                  !ctx->Color.ColorMask[buffer][BCOMP] ||
 365                                  !ctx->Color.ColorMask[buffer][ACOMP]);
 366       GLbitfield mappingFlags = GL_MAP_WRITE_BIT;
 367
 368       if (masking)
 369          mappingFlags |= GL_MAP_READ_BIT;
 370
 371       /* Map color buffer */
 372       ctx->Driver.MapRenderbuffer(ctx, colorRb, xpos, ypos, width, height,
 373                                   mappingFlags, &colorMap, &colorRowStride);
 374       if (!colorMap) {
 375          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 376          continue;
 377       }
 378
 379       if (accRb->Format == MESA_FORMAT_SIGNED_RGBA_16) {
 380          const GLfloat scale = value / 32767.0f;
 381          GLint i, j;
 382          GLfloat (*rgba)[4], (*dest)[4];
 383
 384          rgba = (GLfloat (*)[4]) malloc(width * 4 * sizeof(GLfloat));
 385          dest = (GLfloat (*)[4]) malloc(width * 4 * sizeof(GLfloat));
 386
 387          if (rgba && dest) {
 388             for (j = 0; j < height; j++) {
 389                GLshort *acc = (GLshort *) accMap;
 390
 391                for (i = 0; i < width; i++) {
 392                   rgba[i][0] = acc[i * 4 + 0] * scale;
 393                   rgba[i][1] = acc[i * 4 + 1] * scale;
 394                   rgba[i][2] = acc[i * 4 + 2] * scale;
 395                   rgba[i][3] = acc[i * 4 + 3] * scale;
 396                }
 397
 398                if (masking) {
 399
 400                   /* get existing colors from dest buffer */
 401                   _mesa_unpack_rgba_row(colorRb->Format, width, colorMap, dest);
 402
 403                   /* use the dest colors where mask[channel] = 0 */
 404                   if (ctx->Color.ColorMask[buffer][RCOMP] == 0) {
 405                      for (i = 0; i < width; i++)
 406                         rgba[i][RCOMP] = dest[i][RCOMP];
 407                   }
 408                   if (ctx->Color.ColorMask[buffer][GCOMP] == 0) {
 409                      for (i = 0; i < width; i++)
 410                         rgba[i][GCOMP] = dest[i][GCOMP];
 411                   }
 412                   if (ctx->Color.ColorMask[buffer][BCOMP] == 0) {
 413                      for (i = 0; i < width; i++)
 414                         rgba[i][BCOMP] = dest[i][BCOMP];
 415                   }
 416                   if (ctx->Color.ColorMask[buffer][ACOMP] == 0) {
 417                      for (i = 0; i < width; i++)
 418                         rgba[i][ACOMP] = dest[i][ACOMP];
 419                   }
 420                }
 421
 422                _mesa_pack_float_rgba_row(colorRb->Format, width,
 423                                          (const GLfloat (*)[4]) rgba, colorMap);
 424
 425                accMap += accRowStride;
 426                colorMap += colorRowStride;
 427             }
 428          }
 429          else {
 430             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAccum");
 431          }
 432          free(rgba);
 433          free(dest);
 434       }
 435       else {
 436          /* other types someday? */
 437       }
 438
 439       ctx->Driver.UnmapRenderbuffer(ctx, colorRb);
 440    }
 441
 442    ctx->Driver.UnmapRenderbuffer(ctx, accRb);
 443 }
 444
 445
 446
 447 /**
 448  * Software fallback for glAccum.  A hardware driver that supports
 449  * signed 16-bit color channels could implement hardware accumulation
 450  * operations, but no driver does so at this time.
 451  */
 452 void
 453 _mesa_accum(struct gl_context *ctx, GLenum op, GLfloat value)
 454 {
 455    GLint xpos, ypos, width, height;
 456
 457    if (!ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer) {
 458       _mesa_warning(ctx, "Calling glAccum() without an accumulation buffer");
 459       return;
 460    }
 461
 462    if (!_mesa_check_conditional_render(ctx))
 463       return;
 464
 465    xpos = ctx->DrawBuffer->_Xmin;
 466    ypos = ctx->DrawBuffer->_Ymin;
 467    width =  ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
 468    height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
 469
 470    switch (op) {
 471    case GL_ADD:
 472       if (value != 0.0F) {
 473          accum_scale_or_bias(ctx, value, xpos, ypos, width, height, GL_TRUE);
 474       }
 475       break;
 476    case GL_MULT:
 477       if (value != 1.0F) {
 478          accum_scale_or_bias(ctx, value, xpos, ypos, width, height, GL_FALSE);
 479       }
 480       break;
 481    case GL_ACCUM:
 482       if (value != 0.0F) {
 483          accum_or_load(ctx, value, xpos, ypos, width, height, GL_FALSE);
 484       }
 485       break;
 486    case GL_LOAD:
 487       accum_or_load(ctx, value, xpos, ypos, width, height, GL_TRUE);
 488       break;
 489    case GL_RETURN:
 490       accum_return(ctx, value, xpos, ypos, width, height);
 491       break;
 492    default:
 493       _mesa_problem(ctx, "invalid mode in _mesa_accum()");
 494       break;
 495    }
 496 }
 497
 498
 499 #endif /* FEATURE_accum */
 500
 501
 502 void
 503 _mesa_init_accum( struct gl_context *ctx )
 504 {
 505    /* Accumulate buffer group */
 506    ASSIGN_4V( ctx->Accum.ClearColor, 0.0, 0.0, 0.0, 0.0 );
 507 }