src/mesa/main/buffers.c

   1 /* $Id: buffers.c,v 1.18 2000/10/31 18:09:44 keithw Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2000  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 "context.h"
  35 #include "depth.h"
  36 #include "enums.h"
  37 #include "macros.h"
  38 #include "masking.h"
  39 #include "mem.h"
  40 #include "stencil.h"
  41 #include "state.h"
  42 #include "types.h"
  43 #include "swrast/swrast.h"
  44 #endif
  45
  46
  47
  48 void
  49 _mesa_ClearIndex( GLfloat c )
  50 {
  51    GET_CURRENT_CONTEXT(ctx);
  52    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClearIndex");
  53    ctx->Color.ClearIndex = (GLuint) c;
  54    ctx->NewState |= _NEW_COLOR;
  55
  56    if (!ctx->Visual.RGBAflag) {
  57       /* it's OK to call glClearIndex in RGBA mode but it should be a NOP */
  58       (*ctx->Driver.ClearIndex)( ctx, ctx->Color.ClearIndex );
  59    }
  60 }
  61
  62
  63
  64 void
  65 _mesa_ClearColor( GLclampf red, GLclampf green,
  66                   GLclampf blue, GLclampf alpha )
  67 {
  68    GET_CURRENT_CONTEXT(ctx);
  69    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClearColor");
  70
  71    ctx->Color.ClearColor[0] = CLAMP( red,   0.0F, 1.0F );
  72    ctx->Color.ClearColor[1] = CLAMP( green, 0.0F, 1.0F );
  73    ctx->Color.ClearColor[2] = CLAMP( blue,  0.0F, 1.0F );
  74    ctx->Color.ClearColor[3] = CLAMP( alpha, 0.0F, 1.0F );
  75    ctx->NewState |= _NEW_COLOR;
  76
  77    if (ctx->Visual.RGBAflag) {
  78       GLchan r = (GLint) (ctx->Color.ClearColor[0] * CHAN_MAXF);
  79       GLchan g = (GLint) (ctx->Color.ClearColor[1] * CHAN_MAXF);
  80       GLchan b = (GLint) (ctx->Color.ClearColor[2] * CHAN_MAXF);
  81       GLchan a = (GLint) (ctx->Color.ClearColor[3] * CHAN_MAXF);
  82       (*ctx->Driver.ClearColor)( ctx, r, g, b, a );
  83    }
  84 }
  85
  86
  87
  88
  89
  90
  91 void
  92 _mesa_Clear( GLbitfield mask )
  93 {
  94    GET_CURRENT_CONTEXT(ctx);
  95    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClear");
  96
  97    if (MESA_VERBOSE & VERBOSE_API)
  98       fprintf(stderr, "glClear 0x%x\n", mask);
  99
 100    if (ctx->NewState) {
 101       gl_update_state( ctx );
 102    }
 103
 104    if (ctx->RenderMode==GL_RENDER) {
 105       const GLint x = ctx->DrawBuffer->Xmin;
 106       const GLint y = ctx->DrawBuffer->Ymin;
 107       const GLint height = ctx->DrawBuffer->Ymax - ctx->DrawBuffer->Ymin;
 108       const GLint width  = ctx->DrawBuffer->Xmax - ctx->DrawBuffer->Xmin;
 109       GLbitfield ddMask;
 110       GLbitfield newMask;
 111
 112       /* don't clear depth buffer if depth writing disabled */
 113       if (!ctx->Depth.Mask)
 114          CLEAR_BITS(mask, GL_DEPTH_BUFFER_BIT);
 115
 116       /* Build bitmask to send to driver Clear function */
 117       ddMask = mask & (GL_DEPTH_BUFFER_BIT |
 118                        GL_STENCIL_BUFFER_BIT |
 119                        GL_ACCUM_BUFFER_BIT);
 120       if (mask & GL_COLOR_BUFFER_BIT) {
 121          ddMask |= ctx->Color.DrawDestMask;
 122       }
 123
 124       ASSERT(ctx->Driver.Clear);
 125       newMask = (*ctx->Driver.Clear)( ctx, ddMask, !ctx->Scissor.Enabled,
 126                                       x, y, width, height );
 127
 128 #ifdef DEBUG
 129       {
 130          GLbitfield legalBits = DD_FRONT_LEFT_BIT |
 131                                 DD_FRONT_RIGHT_BIT |
 132                                 DD_BACK_LEFT_BIT |
 133                                 DD_BACK_RIGHT_BIT |
 134                                 DD_DEPTH_BIT |
 135                                 DD_STENCIL_BIT |
 136                                 DD_ACCUM_BIT;
 137          assert((newMask & (~legalBits)) == 0);
 138       }
 139 #endif
 140
 141       if (newMask)
 142          _swrast_Clear( ctx, newMask, !ctx->Scissor.Enabled,
 143                         x, y, width, height );
 144    }
 145 }
 146
 147
 148 void
 149 _mesa_DrawBuffer( GLenum mode )
 150 {
 151    GET_CURRENT_CONTEXT(ctx);
 152    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glDrawBuffer");
 153
 154    if (MESA_VERBOSE & VERBOSE_API)
 155       fprintf(stderr, "glDrawBuffer %s\n", gl_lookup_enum_by_nr(mode));
 156
 157    switch (mode) {
 158       case GL_AUX0:
 159       case GL_AUX1:
 160       case GL_AUX2:
 161       case GL_AUX3:
 162          /* AUX buffers not implemented in Mesa at this time */
 163          gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 164          return;
 165       case GL_RIGHT:
 166          if (!ctx->Visual.StereoFlag) {
 167             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 168             return;}
 169          if (ctx->Visual.DBflag)
 170             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 171          else
 172             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 173          break;
 174       case GL_FRONT_RIGHT:
 175          if (!ctx->Visual.StereoFlag) {
 176             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 177             return;
 178          }
 179          ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 180          break;
 181       case GL_BACK_RIGHT:
 182          if (!ctx->Visual.StereoFlag) {
 183             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 184             return;
 185          }
 186          if (!ctx->Visual.DBflag) {
 187             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 188             return;
 189          }
 190          ctx->Color.DrawDestMask = BACK_RIGHT_BIT;
 191          break;
 192       case GL_BACK_LEFT:
 193          if (!ctx->Visual.DBflag) {
 194             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 195             return;
 196          }
 197          ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 198          break;
 199       case GL_FRONT_AND_BACK:
 200          if (!ctx->Visual.DBflag) {
 201             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 202             return;
 203          }
 204          if (ctx->Visual.StereoFlag)
 205             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
 206                                     | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 207          else
 208             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 209          break;
 210       case GL_BACK:
 211          if (!ctx->Visual.DBflag) {
 212             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 213             return;
 214          }
 215          if (ctx->Visual.StereoFlag)
 216             ctx->Color.DrawDestMask = BACK_LEFT_BIT | BACK_RIGHT_BIT;
 217          else
 218             ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 219          break;
 220       case GL_LEFT:
 221          /* never an error */
 222          if (ctx->Visual.DBflag)
 223             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 224          else
 225             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 226          break;
 227       case GL_FRONT_LEFT:
 228          /* never an error */
 229          ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 230          break;
 231       case GL_FRONT:
 232          /* never an error */
 233          if (ctx->Visual.StereoFlag)
 234             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
 235          else
 236             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 237          break;
 238       case GL_NONE:
 239          /* never an error */
 240          ctx->Color.DrawDestMask = 0;
 241          break;
 242       default:
 243          gl_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
 244          return;
 245    }
 246
 247    /*
 248     * Make the dest buffer mode more precise if possible
 249     */
 250    if (mode == GL_LEFT && !ctx->Visual.DBflag)
 251       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 252    else if (mode == GL_RIGHT && !ctx->Visual.DBflag)
 253       ctx->Color.DriverDrawBuffer = GL_FRONT_RIGHT;
 254    else if (mode == GL_FRONT && !ctx->Visual.StereoFlag)
 255       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 256    else if (mode == GL_BACK && !ctx->Visual.StereoFlag)
 257       ctx->Color.DriverDrawBuffer = GL_BACK_LEFT;
 258    else
 259       ctx->Color.DriverDrawBuffer = mode;
 260
 261    /*
 262     * Set current alpha buffer pointer
 263     */
 264    if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
 265       if (ctx->Color.DriverDrawBuffer == GL_FRONT_LEFT)
 266          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontLeftAlpha;
 267       else if (ctx->Color.DriverDrawBuffer == GL_BACK_LEFT)
 268          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackLeftAlpha;
 269       else if (ctx->Color.DriverDrawBuffer == GL_FRONT_RIGHT)
 270          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontRightAlpha;
 271       else if (ctx->Color.DriverDrawBuffer == GL_BACK_RIGHT)
 272          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackRightAlpha;
 273    }
 274
 275    /*
 276     * If we get here there can't have been an error.
 277     * Now see if device driver can implement the drawing to the target
 278     * buffer(s).  The driver may not be able to do GL_FRONT_AND_BACK mode
 279     * for example.  We'll take care of that in the core code by looping
 280     * over the individual buffers.
 281     */
 282    ASSERT(ctx->Driver.SetDrawBuffer);
 283    if ( (*ctx->Driver.SetDrawBuffer)(ctx, ctx->Color.DriverDrawBuffer) ) {
 284       /* All OK, the driver will do all buffer writes */
 285       ctx->Color.MultiDrawBuffer = GL_FALSE;
 286    }
 287    else {
 288       /* We'll have to loop over the multiple draw buffer targets */
 289       ctx->Color.MultiDrawBuffer = GL_TRUE;
 290       /* Set drawing buffer to front for now */
 291       (void) (*ctx->Driver.SetDrawBuffer)(ctx, GL_FRONT_LEFT);
 292    }
 293
 294    ctx->Color.DrawBuffer = mode;
 295    ctx->NewState |= _NEW_COLOR;
 296 }
 297
 298
 299
 300 void
 301 _mesa_ReadBuffer( GLenum mode )
 302 {
 303    GET_CURRENT_CONTEXT(ctx);
 304    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glReadBuffer");
 305
 306    if (MESA_VERBOSE & VERBOSE_API)
 307       fprintf(stderr, "glReadBuffer %s\n", gl_lookup_enum_by_nr(mode));
 308
 309    switch (mode) {
 310       case GL_AUX0:
 311       case GL_AUX1:
 312       case GL_AUX2:
 313       case GL_AUX3:
 314          /* AUX buffers not implemented in Mesa at this time */
 315          gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 316          return;
 317       case GL_LEFT:
 318       case GL_FRONT:
 319       case GL_FRONT_LEFT:
 320          /* Front-Left buffer, always exists */
 321          ctx->Pixel.DriverReadBuffer = GL_FRONT_LEFT;
 322          break;
 323       case GL_BACK:
 324       case GL_BACK_LEFT:
 325          /* Back-Left buffer, requires double buffering */
 326          if (!ctx->Visual.DBflag) {
 327             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 328             return;
 329          }
 330          ctx->Pixel.DriverReadBuffer = GL_BACK_LEFT;
 331          break;
 332       case GL_FRONT_RIGHT:
 333       case GL_RIGHT:
 334          if (!ctx->Visual.StereoFlag) {
 335             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 336             return;
 337          }
 338          ctx->Pixel.DriverReadBuffer = GL_FRONT_RIGHT;
 339          break;
 340       case GL_BACK_RIGHT:
 341          if (!ctx->Visual.StereoFlag || !ctx->Visual.DBflag) {
 342             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 343             return;
 344          }
 345          ctx->Pixel.DriverReadBuffer = GL_BACK_RIGHT;
 346          break;
 347       default:
 348          gl_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
 349          return;
 350    }
 351
 352    ctx->Pixel.ReadBuffer = mode;
 353    ctx->NewState |= _NEW_PIXEL;
 354 }
 355
 356
 357 /*
 358  * GL_MESA_resize_buffers extension
 359  */
 360 void
 361 _mesa_ResizeBuffersMESA( void )
 362 {
 363    GLcontext *ctx = _mesa_get_current_context();
 364
 365    GLuint buf_width, buf_height;
 366
 367    if (MESA_VERBOSE & VERBOSE_API)
 368       fprintf(stderr, "glResizeBuffersMESA\n");
 369
 370    /* ask device driver for size of output buffer */
 371    (*ctx->Driver.GetBufferSize)( ctx, &buf_width, &buf_height );
 372
 373    /* see if size of device driver's color buffer (window) has changed */
 374    if (ctx->DrawBuffer->Width == (GLint) buf_width &&
 375        ctx->DrawBuffer->Height == (GLint) buf_height)
 376       return;
 377
 378    ctx->NewState |= _NEW_BUFFERS;  /* to update scissor / window bounds */
 379
 380    /* save buffer size */
 381    ctx->DrawBuffer->Width = buf_width;
 382    ctx->DrawBuffer->Height = buf_height;
 383
 384    _swrast_alloc_buffers( ctx );
 385 }