src/mesa/main/buffers.c

   1 /* $Id: buffers.c,v 1.38 2002/10/04 19:10:07 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
 148    if (MESA_VERBOSE & VERBOSE_API)
 149       _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 150
 151    /*
 152     * Do error checking and compute the _DrawDestMask bitfield.
 153     */
 154    switch (mode) {
 155       case GL_AUX0:
 156       case GL_AUX1:
 157       case GL_AUX2:
 158       case GL_AUX3:
 159          /* AUX buffers not implemented in Mesa at this time */
 160          _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 161          return;
 162       case GL_RIGHT:
 163          if (!ctx->Visual.stereoMode) {
 164             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 165             return;}
 166          if (ctx->Visual.doubleBufferMode)
 167             ctx->Color._DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 168          else
 169             ctx->Color._DrawDestMask = FRONT_RIGHT_BIT;
 170          break;
 171       case GL_FRONT_RIGHT:
 172          if (!ctx->Visual.stereoMode) {
 173             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 174             return;
 175          }
 176          ctx->Color._DrawDestMask = FRONT_RIGHT_BIT;
 177          break;
 178       case GL_BACK_RIGHT:
 179          if (!ctx->Visual.stereoMode) {
 180             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 181             return;
 182          }
 183          if (!ctx->Visual.doubleBufferMode) {
 184             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 185             return;
 186          }
 187          ctx->Color._DrawDestMask = BACK_RIGHT_BIT;
 188          break;
 189       case GL_BACK_LEFT:
 190          if (!ctx->Visual.doubleBufferMode) {
 191             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 192             return;
 193          }
 194          ctx->Color._DrawDestMask = BACK_LEFT_BIT;
 195          break;
 196       case GL_FRONT_AND_BACK:
 197          if (!ctx->Visual.doubleBufferMode) {
 198             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 199             return;
 200          }
 201          if (ctx->Visual.stereoMode)
 202             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
 203                                     | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 204          else
 205             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 206          break;
 207       case GL_BACK:
 208          if (!ctx->Visual.doubleBufferMode) {
 209             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 210             return;
 211          }
 212          if (ctx->Visual.stereoMode)
 213             ctx->Color._DrawDestMask = BACK_LEFT_BIT | BACK_RIGHT_BIT;
 214          else
 215             ctx->Color._DrawDestMask = BACK_LEFT_BIT;
 216          break;
 217       case GL_LEFT:
 218          /* never an error */
 219          if (ctx->Visual.doubleBufferMode)
 220             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 221          else
 222             ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 223          break;
 224       case GL_FRONT_LEFT:
 225          /* never an error */
 226          ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 227          break;
 228       case GL_FRONT:
 229          /* never an error */
 230          if (ctx->Visual.stereoMode)
 231             ctx->Color._DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
 232          else
 233             ctx->Color._DrawDestMask = FRONT_LEFT_BIT;
 234          break;
 235       case GL_NONE:
 236          /* never an error */
 237          ctx->Color._DrawDestMask = 0;
 238          break;
 239       default:
 240          _mesa_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
 241          return;
 242    }
 243
 244    ctx->Color.DrawBuffer = mode;
 245    ctx->NewState |= _NEW_COLOR;
 246
 247    /*
 248     * Call device driver function.
 249     */
 250    if (ctx->Driver.DrawBuffer)
 251       (*ctx->Driver.DrawBuffer)(ctx, mode);
 252 }
 253
 254
 255
 256 void
 257 _mesa_ReadBuffer( GLenum mode )
 258 {
 259    GET_CURRENT_CONTEXT(ctx);
 260    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 261
 262    if (MESA_VERBOSE & VERBOSE_API)
 263       _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 264
 265    switch (mode) {
 266       case GL_AUX0:
 267       case GL_AUX1:
 268       case GL_AUX2:
 269       case GL_AUX3:
 270          /* AUX buffers not implemented in Mesa at this time */
 271          _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 272          return;
 273       case GL_LEFT:
 274       case GL_FRONT:
 275       case GL_FRONT_LEFT:
 276          /* Front-Left buffer, always exists */
 277          ctx->Pixel._DriverReadBuffer = GL_FRONT_LEFT;
 278          break;
 279       case GL_BACK:
 280       case GL_BACK_LEFT:
 281          /* Back-Left buffer, requires double buffering */
 282          if (!ctx->Visual.doubleBufferMode) {
 283             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 284             return;
 285          }
 286          ctx->Pixel._DriverReadBuffer = GL_BACK_LEFT;
 287          break;
 288       case GL_FRONT_RIGHT:
 289       case GL_RIGHT:
 290          if (!ctx->Visual.stereoMode) {
 291             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 292             return;
 293          }
 294          ctx->Pixel._DriverReadBuffer = GL_FRONT_RIGHT;
 295          break;
 296       case GL_BACK_RIGHT:
 297          if (!ctx->Visual.stereoMode || !ctx->Visual.doubleBufferMode) {
 298             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 299             return;
 300          }
 301          ctx->Pixel._DriverReadBuffer = GL_BACK_RIGHT;
 302          break;
 303       default:
 304          _mesa_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
 305          return;
 306    }
 307
 308    ctx->Pixel.ReadBuffer = mode;
 309    ctx->NewState |= _NEW_PIXEL;
 310
 311    /*
 312     * Call device driver function.
 313     */
 314    if (ctx->Driver.ReadBuffer)
 315       (*ctx->Driver.ReadBuffer)(ctx, mode);
 316 }
 317
 318
 319 /*
 320  * GL_MESA_resize_buffers extension
 321  * When this function is called, we'll ask the window system how large
 322  * the current window is.  If it's not what we expect, we'll have to
 323  * resize/reallocate the software accum/stencil/depth/alpha buffers.
 324  */
 325 void
 326 _mesa_ResizeBuffersMESA( void )
 327 {
 328    GLcontext *ctx = _mesa_get_current_context();
 329
 330    if (MESA_VERBOSE & VERBOSE_API)
 331       _mesa_debug(ctx, "glResizeBuffersMESA\n");
 332
 333    if (ctx) {
 334       ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 335
 336       if (ctx->DrawBuffer) {
 337          GLuint buf_width, buf_height;
 338          GLframebuffer *buffer = ctx->DrawBuffer;
 339
 340          /* ask device driver for size of output buffer */
 341          (*ctx->Driver.GetBufferSize)( buffer, &buf_width, &buf_height );
 342
 343          /* see if size of device driver's color buffer (window) has changed */
 344          if (buffer->Width == buf_width && buffer->Height == buf_height)
 345             return; /* size is as expected */
 346
 347          buffer->Width = buf_width;
 348          buffer->Height = buf_height;
 349
 350          ctx->Driver.ResizeBuffers( buffer );
 351       }
 352
 353       if (ctx->ReadBuffer && ctx->ReadBuffer != ctx->DrawBuffer) {
 354          GLuint buf_width, buf_height;
 355          GLframebuffer *buffer = ctx->DrawBuffer;
 356
 357          /* ask device driver for size of output buffer */
 358          (*ctx->Driver.GetBufferSize)( buffer, &buf_width, &buf_height );
 359
 360          /* see if size of device driver's color buffer (window) has changed */
 361          if (buffer->Width == buf_width && buffer->Height == buf_height)
 362             return; /* size is as expected */
 363
 364          buffer->Width = buf_width;
 365          buffer->Height = buf_height;
 366
 367          ctx->Driver.ResizeBuffers( buffer );
 368       }
 369
 370       ctx->NewState |= _NEW_BUFFERS;  /* to update scissor / window bounds */
 371    }
 372 }
 373
 374
 375 void
 376 _mesa_Scissor( GLint x, GLint y, GLsizei width, GLsizei height )
 377 {
 378    GET_CURRENT_CONTEXT(ctx);
 379    ASSERT_OUTSIDE_BEGIN_END(ctx);
 380
 381    if (width < 0 || height < 0) {
 382       _mesa_error( ctx, GL_INVALID_VALUE, "glScissor" );
 383       return;
 384    }
 385
 386    if (MESA_VERBOSE & VERBOSE_API)
 387       _mesa_debug(ctx, "glScissor %d %d %d %d\n", x, y, width, height);
 388
 389    if (x == ctx->Scissor.X &&
 390        y == ctx->Scissor.Y &&
 391        width == ctx->Scissor.Width &&
 392        height == ctx->Scissor.Height)
 393       return;
 394
 395    FLUSH_VERTICES(ctx, _NEW_SCISSOR);
 396    ctx->Scissor.X = x;
 397    ctx->Scissor.Y = y;
 398    ctx->Scissor.Width = width;
 399    ctx->Scissor.Height = height;
 400
 401    if (ctx->Driver.Scissor)
 402       ctx->Driver.Scissor( ctx, x, y, width, height );
 403 }
 404
 405
 406 /*
 407  * XXX move somewhere else someday?
 408  */
 409 void
 410 _mesa_SampleCoverageARB(GLclampf value, GLboolean invert)
 411 {
 412    GLcontext *ctx = _mesa_get_current_context();
 413
 414    if (!ctx->Extensions.ARB_multisample) {
 415       _mesa_error(ctx, GL_INVALID_OPERATION, "glSampleCoverageARB");
 416       return;
 417    }
 418
 419    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 420    ctx->Multisample.SampleCoverageValue = (GLfloat) CLAMP(value, 0.0, 1.0);
 421    ctx->Multisample.SampleCoverageInvert = invert;
 422    ctx->NewState |= _NEW_MULTISAMPLE;
 423 }
 424