src/mesa/main/buffers.c

   1 /* $Id: buffers.c,v 1.27 2001/03/03 20:33:27 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2001  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 "masking.h"
  40 #include "mem.h"
  41 #include "stencil.h"
  42 #include "state.h"
  43 #include "mtypes.h"
  44 #endif
  45
  46
  47
  48 void
  49 _mesa_ClearIndex( GLfloat c )
  50 {
  51    GET_CURRENT_CONTEXT(ctx);
  52    ASSERT_OUTSIDE_BEGIN_END(ctx);
  53
  54    if (ctx->Color.ClearIndex == (GLuint) c)
  55       return;
  56
  57    FLUSH_VERTICES(ctx, _NEW_COLOR);
  58    ctx->Color.ClearIndex = (GLuint) c;
  59
  60    if (!ctx->Visual.rgbMode && ctx->Driver.ClearIndex) {
  61       /* it's OK to call glClearIndex in RGBA mode but it should be a NOP */
  62       (*ctx->Driver.ClearIndex)( ctx, ctx->Color.ClearIndex );
  63    }
  64 }
  65
  66
  67
  68 void
  69 _mesa_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
  70 {
  71    GLchan tmp[4];
  72    GET_CURRENT_CONTEXT(ctx);
  73    ASSERT_OUTSIDE_BEGIN_END(ctx);
  74
  75    UNCLAMPED_FLOAT_TO_CHAN(tmp[0], red);
  76    UNCLAMPED_FLOAT_TO_CHAN(tmp[1], green);
  77    UNCLAMPED_FLOAT_TO_CHAN(tmp[2], blue);
  78    UNCLAMPED_FLOAT_TO_CHAN(tmp[3], alpha);
  79
  80    if (TEST_EQ_4V(tmp, ctx->Color.ClearColor))
  81       return;
  82
  83    FLUSH_VERTICES(ctx, _NEW_COLOR);
  84    COPY_CHAN4(ctx->Color.ClearColor, tmp);
  85
  86    if (ctx->Visual.rgbMode && ctx->Driver.ClearColor) {
  87       /* it's OK to call glClearColor in CI mode but it should be a NOP */
  88       (*ctx->Driver.ClearColor)(ctx, ctx->Color.ClearColor);
  89    }
  90 }
  91
  92
  93
  94 void
  95 _mesa_Clear( GLbitfield mask )
  96 {
  97    GET_CURRENT_CONTEXT(ctx);
  98    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
  99
 100    if (MESA_VERBOSE & VERBOSE_API)
 101       fprintf(stderr, "glClear 0x%x\n", mask);
 102
 103    if (ctx->NewState) {
 104       _mesa_update_state( ctx );        /* update _Xmin, etc */
 105    }
 106
 107    if (ctx->RenderMode==GL_RENDER) {
 108       const GLint x = ctx->DrawBuffer->_Xmin;
 109       const GLint y = ctx->DrawBuffer->_Ymin;
 110       const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
 111       const GLint width  = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
 112       GLbitfield ddMask;
 113
 114       /* don't clear depth buffer if depth writing disabled */
 115       if (!ctx->Depth.Mask)
 116          CLEAR_BITS(mask, GL_DEPTH_BUFFER_BIT);
 117
 118       /* Build bitmask to send to driver Clear function */
 119       ddMask = mask & (GL_DEPTH_BUFFER_BIT |
 120                        GL_STENCIL_BUFFER_BIT |
 121                        GL_ACCUM_BUFFER_BIT);
 122       if (mask & GL_COLOR_BUFFER_BIT) {
 123          ddMask |= ctx->Color.DrawDestMask;
 124       }
 125
 126       ASSERT(ctx->Driver.Clear);
 127       ctx->Driver.Clear( ctx, ddMask, !ctx->Scissor.Enabled,
 128                          x, y, width, height );
 129    }
 130 }
 131
 132
 133 void
 134 _mesa_DrawBuffer( GLenum mode )
 135 {
 136    GET_CURRENT_CONTEXT(ctx);
 137    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
 138
 139
 140    if (MESA_VERBOSE & VERBOSE_API)
 141       fprintf(stderr, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 142
 143    switch (mode) {
 144       case GL_AUX0:
 145       case GL_AUX1:
 146       case GL_AUX2:
 147       case GL_AUX3:
 148          /* AUX buffers not implemented in Mesa at this time */
 149          _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 150          return;
 151       case GL_RIGHT:
 152          if (!ctx->Visual.stereoMode) {
 153             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 154             return;}
 155          if (ctx->Visual.doubleBufferMode)
 156             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 157          else
 158             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 159          break;
 160       case GL_FRONT_RIGHT:
 161          if (!ctx->Visual.stereoMode) {
 162             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 163             return;
 164          }
 165          ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 166          break;
 167       case GL_BACK_RIGHT:
 168          if (!ctx->Visual.stereoMode) {
 169             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 170             return;
 171          }
 172          if (!ctx->Visual.doubleBufferMode) {
 173             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 174             return;
 175          }
 176          ctx->Color.DrawDestMask = BACK_RIGHT_BIT;
 177          break;
 178       case GL_BACK_LEFT:
 179          if (!ctx->Visual.doubleBufferMode) {
 180             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 181             return;
 182          }
 183          ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 184          break;
 185       case GL_FRONT_AND_BACK:
 186          if (!ctx->Visual.doubleBufferMode) {
 187             _mesa_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 188             return;
 189          }
 190          if (ctx->Visual.stereoMode)
 191             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
 192                                     | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 193          else
 194             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 195          break;
 196       case GL_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 = BACK_LEFT_BIT | BACK_RIGHT_BIT;
 203          else
 204             ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 205          break;
 206       case GL_LEFT:
 207          /* never an error */
 208          if (ctx->Visual.doubleBufferMode)
 209             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 210          else
 211             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 212          break;
 213       case GL_FRONT_LEFT:
 214          /* never an error */
 215          ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 216          break;
 217       case GL_FRONT:
 218          /* never an error */
 219          if (ctx->Visual.stereoMode)
 220             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
 221          else
 222             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 223          break;
 224       case GL_NONE:
 225          /* never an error */
 226          ctx->Color.DrawDestMask = 0;
 227          break;
 228       default:
 229          _mesa_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
 230          return;
 231    }
 232
 233    /*
 234     * Make the dest buffer mode more precise if possible
 235     */
 236    if (mode == GL_LEFT && !ctx->Visual.doubleBufferMode)
 237       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 238    else if (mode == GL_RIGHT && !ctx->Visual.doubleBufferMode)
 239       ctx->Color.DriverDrawBuffer = GL_FRONT_RIGHT;
 240    else if (mode == GL_FRONT && !ctx->Visual.stereoMode)
 241       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 242    else if (mode == GL_BACK && !ctx->Visual.stereoMode)
 243       ctx->Color.DriverDrawBuffer = GL_BACK_LEFT;
 244    else
 245       ctx->Color.DriverDrawBuffer = mode;
 246
 247    /*
 248     * Set current alpha buffer pointer
 249     */
 250    if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
 251       if (ctx->Color.DriverDrawBuffer == GL_FRONT_LEFT)
 252          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontLeftAlpha;
 253       else if (ctx->Color.DriverDrawBuffer == GL_BACK_LEFT)
 254          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackLeftAlpha;
 255       else if (ctx->Color.DriverDrawBuffer == GL_FRONT_RIGHT)
 256          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontRightAlpha;
 257       else if (ctx->Color.DriverDrawBuffer == GL_BACK_RIGHT)
 258          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackRightAlpha;
 259    }
 260
 261    /*
 262     * If we get here there can't have been an error.
 263     * Now see if device driver can implement the drawing to the target
 264     * buffer(s).  The driver may not be able to do GL_FRONT_AND_BACK mode
 265     * for example.  We'll take care of that in the core code by looping
 266     * over the individual buffers.
 267     */
 268    ASSERT(ctx->Driver.SetDrawBuffer);
 269    if ( (*ctx->Driver.SetDrawBuffer)(ctx, ctx->Color.DriverDrawBuffer) ) {
 270       /* All OK, the driver will do all buffer writes */
 271       ctx->Color.MultiDrawBuffer = GL_FALSE;
 272    }
 273    else {
 274       /* We'll have to loop over the multiple draw buffer targets */
 275       ctx->Color.MultiDrawBuffer = GL_TRUE;
 276       /* Set drawing buffer to front for now */
 277       (void) (*ctx->Driver.SetDrawBuffer)(ctx, GL_FRONT_LEFT);
 278    }
 279
 280    ctx->Color.DrawBuffer = mode;
 281    ctx->NewState |= _NEW_COLOR;
 282 }
 283
 284
 285
 286 void
 287 _mesa_ReadBuffer( GLenum mode )
 288 {
 289    GET_CURRENT_CONTEXT(ctx);
 290    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 291
 292    if (MESA_VERBOSE & VERBOSE_API)
 293       fprintf(stderr, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 294
 295    switch (mode) {
 296       case GL_AUX0:
 297       case GL_AUX1:
 298       case GL_AUX2:
 299       case GL_AUX3:
 300          /* AUX buffers not implemented in Mesa at this time */
 301          _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 302          return;
 303       case GL_LEFT:
 304       case GL_FRONT:
 305       case GL_FRONT_LEFT:
 306          /* Front-Left buffer, always exists */
 307          ctx->Pixel.DriverReadBuffer = GL_FRONT_LEFT;
 308          break;
 309       case GL_BACK:
 310       case GL_BACK_LEFT:
 311          /* Back-Left buffer, requires double buffering */
 312          if (!ctx->Visual.doubleBufferMode) {
 313             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 314             return;
 315          }
 316          ctx->Pixel.DriverReadBuffer = GL_BACK_LEFT;
 317          break;
 318       case GL_FRONT_RIGHT:
 319       case GL_RIGHT:
 320          if (!ctx->Visual.stereoMode) {
 321             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 322             return;
 323          }
 324          ctx->Pixel.DriverReadBuffer = GL_FRONT_RIGHT;
 325          break;
 326       case GL_BACK_RIGHT:
 327          if (!ctx->Visual.stereoMode || !ctx->Visual.doubleBufferMode) {
 328             _mesa_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 329             return;
 330          }
 331          ctx->Pixel.DriverReadBuffer = GL_BACK_RIGHT;
 332          break;
 333       default:
 334          _mesa_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
 335          return;
 336    }
 337
 338    ctx->Pixel.ReadBuffer = mode;
 339    ctx->NewState |= _NEW_PIXEL;
 340 }
 341
 342
 343 /*
 344  * GL_MESA_resize_buffers extension
 345  */
 346 void
 347 _mesa_ResizeBuffersMESA( void )
 348 {
 349    GLcontext *ctx = _mesa_get_current_context();
 350    GLuint buf_width, buf_height;
 351    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 352
 353
 354    if (MESA_VERBOSE & VERBOSE_API)
 355       fprintf(stderr, "glResizeBuffersMESA\n");
 356
 357    /* ask device driver for size of output buffer */
 358    (*ctx->Driver.GetBufferSize)( ctx, &buf_width, &buf_height );
 359
 360    /* see if size of device driver's color buffer (window) has changed */
 361    if (ctx->DrawBuffer->Width == (GLint) buf_width &&
 362        ctx->DrawBuffer->Height == (GLint) buf_height)
 363       return;
 364
 365    ctx->NewState |= _NEW_BUFFERS;  /* to update scissor / window bounds */
 366
 367    /* save buffer size */
 368    ctx->DrawBuffer->Width = buf_width;
 369    ctx->DrawBuffer->Height = buf_height;
 370
 371    ctx->Driver.ResizeBuffersMESA( ctx );
 372 }