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