src/mesa/main/buffers.c

   1 /* $Id: buffers.c,v 1.40 2002/10/11 15:17:12 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  4.1
   6  *
   7  * Copyright (C) 1999-2002  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 #ifdef PC_HEADER
  29 #include "all.h"
  30 #else
  31 #include "glheader.h"
  32 #include "accum.h"
  33 #include "buffers.h"
  34 #include "colormac.h"
  35 #include "context.h"
  36 #include "depth.h"
  37 #include "enums.h"
  38 #include "macros.h"
  39 #include "mem.h"
  40 #include "stencil.h"
  41 #include "state.h"
  42 #include "mtypes.h"
  43 #endif
  44
  45
  46
  47 void
  48 _mesa_ClearIndex( GLfloat c )
  49 {
  50    GET_CURRENT_CONTEXT(ctx);
  51    ASSERT_OUTSIDE_BEGIN_END(ctx);
  52
  53    if (ctx->Color.ClearIndex == (GLuint) c)
  54       return;
  55
  56    FLUSH_VERTICES(ctx, _NEW_COLOR);
  57    ctx->Color.ClearIndex = (GLuint) c;
  58
  59    if (!ctx->Visual.rgbMode && ctx->Driver.ClearIndex) {
  60       /* it's OK to call glClearIndex in RGBA mode but it should be a NOP */
  61       (*ctx->Driver.ClearIndex)( ctx, ctx->Color.ClearIndex );
  62    }
  63 }
  64
  65
  66
  67 void
  68 _mesa_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
  69 {
  70    GLfloat tmp[4];
  71    GET_CURRENT_CONTEXT(ctx);
  72    ASSERT_OUTSIDE_BEGIN_END(ctx);
  73
  74    tmp[0] = CLAMP(red,   0.0F, 1.0F);
  75    tmp[1] = CLAMP(green, 0.0F, 1.0F);
  76    tmp[2] = CLAMP(blue,  0.0F, 1.0F);
  77    tmp[3] = CLAMP(alpha, 0.0F, 1.0F);
  78
  79    if (TEST_EQ_4V(tmp, ctx->Color.ClearColor))
  80       return; /* no change */
  81
  82    FLUSH_VERTICES(ctx, _NEW_COLOR);
  83    COPY_4V(ctx->Color.ClearColor, tmp);
  84
  85    if (ctx->Visual.rgbMode && ctx->Driver.ClearColor) {
  86       /* it's OK to call glClearColor in CI mode but it should be a NOP */
  87       (*ctx->Driver.ClearColor)(ctx, ctx->Color.ClearColor);
  88    }
  89 }
  90
  91
  92
  93 void
  94 _mesa_Clear( GLbitfield mask )
  95 {
  96    GET_CURRENT_CONTEXT(ctx);
  97    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
  98
  99    if (MESA_VERBOSE & VERBOSE_API)
 100       _mesa_debug(ctx, "glClear 0x%x\n", mask);
 101
 102    if (mask & ~(GL_COLOR_BUFFER_BIT |
 103                 GL_DEPTH_BUFFER_BIT |
 104                 GL_STENCIL_BUFFER_BIT |
 105                 GL_ACCUM_BUFFER_BIT)) {
 106       /* invalid bit set */
 107       _mesa_error( ctx, GL_INVALID_VALUE, "glClear(mask)");
 108       return;
 109    }
 110
 111    if (ctx->NewState) {
 112       _mesa_update_state( ctx );        /* update _Xmin, etc */
 113    }
 114
 115    if (ctx->RenderMode==GL_RENDER) {
 116       const GLint x = ctx->DrawBuffer->_Xmin;
 117       const GLint y = ctx->DrawBuffer->_Ymin;
 118       const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
 119       const GLint width  = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
 120       GLbitfield ddMask;
 121
 122       /* don't clear depth buffer if depth writing disabled */
 123       if (!ctx->Depth.Mask)
 124          mask &= ~GL_DEPTH_BUFFER_BIT;
 125
 126       /* Build bitmask to send to driver Clear function */
 127       ddMask = mask & (GL_DEPTH_BUFFER_BIT |
 128                        GL_STENCIL_BUFFER_BIT |
 129                        GL_ACCUM_BUFFER_BIT);
 130       if (mask & GL_COLOR_BUFFER_BIT) {
 131          ddMask |= ctx->Color._DrawDestMask;
 132       }
 133
 134       ASSERT(ctx->Driver.Clear);
 135       ctx->Driver.Clear( ctx, ddMask, (GLboolean) !ctx->Scissor.Enabled,
 136                          x, y, width, height );
 137    }
 138 }
 139
 140
 141 void
 142 _mesa_DrawBuffer( GLenum mode )
 143 {
 144    GET_CURRENT_CONTEXT(ctx);
 145    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
 146
 147    if (MESA_VERBOSE & VERBOSE_API)
 148       _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 149
 150    /*
 151     * Do error checking and compute the _DrawDestMask bitfield.
 152     */
 153    switch (mode) {
 154       case GL_AUX0:
 155       case GL_AUX1:
 156       case GL_AUX2:
 157       case GL_AUX3:
 158          /* AUX buffers not implemented in Mesa at this time */
 159          _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 160          return;
 161       case GL_RIGHT:
 162          if (!ctx->Visual.stereoMode) {
 163             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 164             return;}
 165          if (ctx->Visual.doubleBufferMode)
 166             ctx->Color._DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 167          else
 168             ctx->Color._DrawDestMask = FRONT_RIGHT_BIT;
 169          break;
 170       case GL_FRONT_RIGHT:
 171          if (!ctx->Visual.stereoMode) {
 172             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 173             return;
 174          }
 175          ctx->Color._DrawDestMask = FRONT_RIGHT_BIT;
 176          break;
 177       case GL_BACK_RIGHT:
 178          if (!ctx->Visual.stereoMode) {
 179             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 180             return;
 181          }
 182          if (!ctx->Visual.doubleBufferMode) {
 183             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 184             return;
 185          }
 186          ctx->Color._DrawDestMask = BACK_RIGHT_BIT;
 187          break;
 188       case GL_BACK_LEFT:
 189          if (!ctx->Visual.doubleBufferMode) {
 190             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 191             return;
 192          }
 193          ctx->Color._DrawDestMask = BACK_LEFT_BIT;
 194          break;
 195       case GL_FRONT_AND_BACK:
 196          if (!ctx->Visual.doubleBufferMode) {
 197             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 198             return;
 199          }
 200          if (ctx->Visual.stereoMode)
 201             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
 202                                     | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 203          else
 204             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 205          break;
 206       case GL_BACK:
 207          if (!ctx->Visual.doubleBufferMode) {
 208             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 209             return;
 210          }
 211          if (ctx->Visual.stereoMode)
 212             ctx->Color._DrawDestMask = BACK_LEFT_BIT | BACK_RIGHT_BIT;
 213          else
 214             ctx->Color._DrawDestMask = BACK_LEFT_BIT;
 215          break;
 216       case GL_LEFT:
 217          /* never an error */
 218          if (ctx->Visual.doubleBufferMode)
 219             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 220          else
 221             ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 222          break;
 223       case GL_FRONT_LEFT:
 224          /* never an error */
 225          ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 226          break;
 227       case GL_FRONT:
 228          /* never an error */
 229          if (ctx->Visual.stereoMode)
 230             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
 231          else
 232             ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 233          break;
 234       case GL_NONE:
 235          /* never an error */
 236          ctx->Color._DrawDestMask = 0;
 237          break;
 238       default:
 239          _mesa_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
 240          return;
 241    }
 242
 243    ctx->Color.DrawBuffer = mode;
 244    ctx->NewState |= _NEW_COLOR;
 245
 246    /*
 247     * Call device driver function.
 248     */
 249    if (ctx->Driver.DrawBuffer)
 250       (*ctx->Driver.DrawBuffer)(ctx, mode);
 251 }
 252
 253
 254
 255 void
 256 _mesa_ReadBuffer( GLenum mode )
 257 {
 258    GET_CURRENT_CONTEXT(ctx);
 259    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 260
 261    if (MESA_VERBOSE & VERBOSE_API)
 262       _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 263
 264    if (ctx->Pixel.ReadBuffer == mode)
 265       return; /* no change */
 266
 267    switch (mode) {
 268       case GL_AUX0:
 269       case GL_AUX1:
 270       case GL_AUX2:
 271       case GL_AUX3:
 272          /* AUX buffers not implemented in Mesa at this time */
 273          _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 274          return;
 275       case GL_LEFT:
 276       case GL_FRONT:
 277       case GL_FRONT_LEFT:
 278          /* Front-Left buffer, always exists */
 279          ctx->Pixel._DriverReadBuffer = GL_FRONT_LEFT;
 280          break;
 281       case GL_BACK:
 282       case GL_BACK_LEFT:
 283          /* Back-Left buffer, requires double buffering */
 284          if (!ctx->Visual.doubleBufferMode) {
 285             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 286             return;
 287          }
 288          ctx->Pixel._DriverReadBuffer = GL_BACK_LEFT;
 289          break;
 290       case GL_FRONT_RIGHT:
 291       case GL_RIGHT:
 292          if (!ctx->Visual.stereoMode) {
 293             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 294             return;
 295          }
 296          ctx->Pixel._DriverReadBuffer = GL_FRONT_RIGHT;
 297          break;
 298       case GL_BACK_RIGHT:
 299          if (!ctx->Visual.stereoMode || !ctx->Visual.doubleBufferMode) {
 300             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 301             return;
 302          }
 303          ctx->Pixel._DriverReadBuffer = GL_BACK_RIGHT;
 304          break;
 305       default:
 306          _mesa_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
 307          return;
 308    }
 309
 310    ctx->Pixel.ReadBuffer = mode;
 311    ctx->NewState |= _NEW_PIXEL;
 312
 313    /*
 314     * Call device driver function.
 315     */
 316    if (ctx->Driver.ReadBuffer)
 317       (*ctx->Driver.ReadBuffer)(ctx, mode);
 318 }
 319
 320
 321 /*
 322  * GL_MESA_resize_buffers extension
 323  * When this function is called, we'll ask the window system how large
 324  * the current window is.  If it's not what we expect, we'll have to
 325  * resize/reallocate the software accum/stencil/depth/alpha buffers.
 326  */
 327 void
 328 _mesa_ResizeBuffersMESA( void )
 329 {
 330    GLcontext *ctx = _mesa_get_current_context();
 331
 332    if (MESA_VERBOSE & VERBOSE_API)
 333       _mesa_debug(ctx, "glResizeBuffersMESA\n");
 334
 335    if (ctx) {
 336       ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 337
 338       if (ctx->DrawBuffer) {
 339          GLuint buf_width, buf_height;
 340          GLframebuffer *buffer = ctx->DrawBuffer;
 341
 342          /* ask device driver for size of output buffer */
 343          (*ctx->Driver.GetBufferSize)( buffer, &buf_width, &buf_height );
 344
 345          /* see if size of device driver's color buffer (window) has changed */
 346          if (buffer->Width == buf_width && buffer->Height == buf_height)
 347             return; /* size is as expected */
 348
 349          buffer->Width = buf_width;
 350          buffer->Height = buf_height;
 351
 352          ctx->Driver.ResizeBuffers( buffer );
 353       }
 354
 355       if (ctx->ReadBuffer && ctx->ReadBuffer != ctx->DrawBuffer) {
 356          GLuint buf_width, buf_height;
 357          GLframebuffer *buffer = ctx->DrawBuffer;
 358
 359          /* ask device driver for size of output buffer */
 360          (*ctx->Driver.GetBufferSize)( buffer, &buf_width, &buf_height );
 361
 362          /* see if size of device driver's color buffer (window) has changed */
 363          if (buffer->Width == buf_width && buffer->Height == buf_height)
 364             return; /* size is as expected */
 365
 366          buffer->Width = buf_width;
 367          buffer->Height = buf_height;
 368
 369          ctx->Driver.ResizeBuffers( buffer );
 370       }
 371
 372       ctx->NewState |= _NEW_BUFFERS;  /* to update scissor / window bounds */
 373    }
 374 }
 375
 376
 377 void
 378 _mesa_Scissor( GLint x, GLint y, GLsizei width, GLsizei height )
 379 {
 380    GET_CURRENT_CONTEXT(ctx);
 381    ASSERT_OUTSIDE_BEGIN_END(ctx);
 382
 383    if (width < 0 || height < 0) {
 384       _mesa_error( ctx, GL_INVALID_VALUE, "glScissor" );
 385       return;
 386    }
 387
 388    if (MESA_VERBOSE & VERBOSE_API)
 389       _mesa_debug(ctx, "glScissor %d %d %d %d\n", x, y, width, height);
 390
 391    if (x == ctx->Scissor.X &&
 392        y == ctx->Scissor.Y &&
 393        width == ctx->Scissor.Width &&
 394        height == ctx->Scissor.Height)
 395       return;
 396
 397    FLUSH_VERTICES(ctx, _NEW_SCISSOR);
 398    ctx->Scissor.X = x;
 399    ctx->Scissor.Y = y;
 400    ctx->Scissor.Width = width;
 401    ctx->Scissor.Height = height;
 402
 403    if (ctx->Driver.Scissor)
 404       ctx->Driver.Scissor( ctx, x, y, width, height );
 405 }
 406
 407
 408 /*
 409  * XXX move somewhere else someday?
 410  */
 411 void
 412 _mesa_SampleCoverageARB(GLclampf value, GLboolean invert)
 413 {
 414    GLcontext *ctx = _mesa_get_current_context();
 415
 416    if (!ctx->Extensions.ARB_multisample) {
 417       _mesa_error(ctx, GL_INVALID_OPERATION, "glSampleCoverageARB");
 418       return;
 419    }
 420
 421    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 422    ctx->Multisample.SampleCoverageValue = (GLfloat) CLAMP(value, 0.0, 1.0);
 423    ctx->Multisample.SampleCoverageInvert = invert;
 424    ctx->NewState |= _NEW_MULTISAMPLE;
 425 }
 426