src/mesa/main/buffers.c

   1 /* $Id: buffers.c,v 1.25 2001/01/29 20:47:39 keithw 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       gl_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       GLbitfield newMask;
 114
 115       /* don't clear depth buffer if depth writing disabled */
 116       if (!ctx->Depth.Mask)
 117          CLEAR_BITS(mask, GL_DEPTH_BUFFER_BIT);
 118
 119       /* Build bitmask to send to driver Clear function */
 120       ddMask = mask & (GL_DEPTH_BUFFER_BIT |
 121                        GL_STENCIL_BUFFER_BIT |
 122                        GL_ACCUM_BUFFER_BIT);
 123       if (mask & GL_COLOR_BUFFER_BIT) {
 124          ddMask |= ctx->Color.DrawDestMask;
 125       }
 126
 127       ASSERT(ctx->Driver.Clear);
 128       ctx->Driver.Clear( ctx, ddMask, !ctx->Scissor.Enabled,
 129                          x, y, width, height );
 130    }
 131 }
 132
 133
 134 void
 135 _mesa_DrawBuffer( GLenum mode )
 136 {
 137    GET_CURRENT_CONTEXT(ctx);
 138    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
 139
 140
 141    if (MESA_VERBOSE & VERBOSE_API)
 142       fprintf(stderr, "glDrawBuffer %s\n", gl_lookup_enum_by_nr(mode));
 143
 144    switch (mode) {
 145       case GL_AUX0:
 146       case GL_AUX1:
 147       case GL_AUX2:
 148       case GL_AUX3:
 149          /* AUX buffers not implemented in Mesa at this time */
 150          gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 151          return;
 152       case GL_RIGHT:
 153          if (!ctx->Visual.stereoMode) {
 154             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 155             return;}
 156          if (ctx->Visual.doubleBufferMode)
 157             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 158          else
 159             ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 160          break;
 161       case GL_FRONT_RIGHT:
 162          if (!ctx->Visual.stereoMode) {
 163             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 164             return;
 165          }
 166          ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
 167          break;
 168       case GL_BACK_RIGHT:
 169          if (!ctx->Visual.stereoMode) {
 170             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 171             return;
 172          }
 173          if (!ctx->Visual.doubleBufferMode) {
 174             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 175             return;
 176          }
 177          ctx->Color.DrawDestMask = BACK_RIGHT_BIT;
 178          break;
 179       case GL_BACK_LEFT:
 180          if (!ctx->Visual.doubleBufferMode) {
 181             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 182             return;
 183          }
 184          ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 185          break;
 186       case GL_FRONT_AND_BACK:
 187          if (!ctx->Visual.doubleBufferMode) {
 188             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 189             return;
 190          }
 191          if (ctx->Visual.stereoMode)
 192             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
 193                                     | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
 194          else
 195             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 196          break;
 197       case GL_BACK:
 198          if (!ctx->Visual.doubleBufferMode) {
 199             gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
 200             return;
 201          }
 202          if (ctx->Visual.stereoMode)
 203             ctx->Color.DrawDestMask = BACK_LEFT_BIT | BACK_RIGHT_BIT;
 204          else
 205             ctx->Color.DrawDestMask = BACK_LEFT_BIT;
 206          break;
 207       case GL_LEFT:
 208          /* never an error */
 209          if (ctx->Visual.doubleBufferMode)
 210             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
 211          else
 212             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 213          break;
 214       case GL_FRONT_LEFT:
 215          /* never an error */
 216          ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 217          break;
 218       case GL_FRONT:
 219          /* never an error */
 220          if (ctx->Visual.stereoMode)
 221             ctx->Color.DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
 222          else
 223             ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
 224          break;
 225       case GL_NONE:
 226          /* never an error */
 227          ctx->Color.DrawDestMask = 0;
 228          break;
 229       default:
 230          gl_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
 231          return;
 232    }
 233
 234    /*
 235     * Make the dest buffer mode more precise if possible
 236     */
 237    if (mode == GL_LEFT && !ctx->Visual.doubleBufferMode)
 238       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 239    else if (mode == GL_RIGHT && !ctx->Visual.doubleBufferMode)
 240       ctx->Color.DriverDrawBuffer = GL_FRONT_RIGHT;
 241    else if (mode == GL_FRONT && !ctx->Visual.stereoMode)
 242       ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
 243    else if (mode == GL_BACK && !ctx->Visual.stereoMode)
 244       ctx->Color.DriverDrawBuffer = GL_BACK_LEFT;
 245    else
 246       ctx->Color.DriverDrawBuffer = mode;
 247
 248    /*
 249     * Set current alpha buffer pointer
 250     */
 251    if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
 252       if (ctx->Color.DriverDrawBuffer == GL_FRONT_LEFT)
 253          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontLeftAlpha;
 254       else if (ctx->Color.DriverDrawBuffer == GL_BACK_LEFT)
 255          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackLeftAlpha;
 256       else if (ctx->Color.DriverDrawBuffer == GL_FRONT_RIGHT)
 257          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontRightAlpha;
 258       else if (ctx->Color.DriverDrawBuffer == GL_BACK_RIGHT)
 259          ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackRightAlpha;
 260    }
 261
 262    /*
 263     * If we get here there can't have been an error.
 264     * Now see if device driver can implement the drawing to the target
 265     * buffer(s).  The driver may not be able to do GL_FRONT_AND_BACK mode
 266     * for example.  We'll take care of that in the core code by looping
 267     * over the individual buffers.
 268     */
 269    ASSERT(ctx->Driver.SetDrawBuffer);
 270    if ( (*ctx->Driver.SetDrawBuffer)(ctx, ctx->Color.DriverDrawBuffer) ) {
 271       /* All OK, the driver will do all buffer writes */
 272       ctx->Color.MultiDrawBuffer = GL_FALSE;
 273    }
 274    else {
 275       /* We'll have to loop over the multiple draw buffer targets */
 276       ctx->Color.MultiDrawBuffer = GL_TRUE;
 277       /* Set drawing buffer to front for now */
 278       (void) (*ctx->Driver.SetDrawBuffer)(ctx, GL_FRONT_LEFT);
 279    }
 280
 281    ctx->Color.DrawBuffer = mode;
 282    ctx->NewState |= _NEW_COLOR;
 283 }
 284
 285
 286
 287 void
 288 _mesa_ReadBuffer( GLenum mode )
 289 {
 290    GET_CURRENT_CONTEXT(ctx);
 291    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 292
 293    if (MESA_VERBOSE & VERBOSE_API)
 294       fprintf(stderr, "glReadBuffer %s\n", gl_lookup_enum_by_nr(mode));
 295
 296    switch (mode) {
 297       case GL_AUX0:
 298       case GL_AUX1:
 299       case GL_AUX2:
 300       case GL_AUX3:
 301          /* AUX buffers not implemented in Mesa at this time */
 302          gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 303          return;
 304       case GL_LEFT:
 305       case GL_FRONT:
 306       case GL_FRONT_LEFT:
 307          /* Front-Left buffer, always exists */
 308          ctx->Pixel.DriverReadBuffer = GL_FRONT_LEFT;
 309          break;
 310       case GL_BACK:
 311       case GL_BACK_LEFT:
 312          /* Back-Left buffer, requires double buffering */
 313          if (!ctx->Visual.doubleBufferMode) {
 314             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 315             return;
 316          }
 317          ctx->Pixel.DriverReadBuffer = GL_BACK_LEFT;
 318          break;
 319       case GL_FRONT_RIGHT:
 320       case GL_RIGHT:
 321          if (!ctx->Visual.stereoMode) {
 322             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 323             return;
 324          }
 325          ctx->Pixel.DriverReadBuffer = GL_FRONT_RIGHT;
 326          break;
 327       case GL_BACK_RIGHT:
 328          if (!ctx->Visual.stereoMode || !ctx->Visual.doubleBufferMode) {
 329             gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
 330             return;
 331          }
 332          ctx->Pixel.DriverReadBuffer = GL_BACK_RIGHT;
 333          break;
 334       default:
 335          gl_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
 336          return;
 337    }
 338
 339    ctx->Pixel.ReadBuffer = mode;
 340    ctx->NewState |= _NEW_PIXEL;
 341 }
 342
 343
 344 /*
 345  * GL_MESA_resize_buffers extension
 346  */
 347 void
 348 _mesa_ResizeBuffersMESA( void )
 349 {
 350    GLcontext *ctx = _mesa_get_current_context();
 351    GLuint buf_width, buf_height;
 352    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
 353
 354
 355    if (MESA_VERBOSE & VERBOSE_API)
 356       fprintf(stderr, "glResizeBuffersMESA\n");
 357
 358    /* ask device driver for size of output buffer */
 359    (*ctx->Driver.GetBufferSize)( ctx, &buf_width, &buf_height );
 360
 361    /* see if size of device driver's color buffer (window) has changed */
 362    if (ctx->DrawBuffer->Width == (GLint) buf_width &&
 363        ctx->DrawBuffer->Height == (GLint) buf_height)
 364       return;
 365
 366    ctx->NewState |= _NEW_BUFFERS;  /* to update scissor / window bounds */
 367
 368    /* save buffer size */
 369    ctx->DrawBuffer->Width = buf_width;
 370    ctx->DrawBuffer->Height = buf_height;
 371
 372    ctx->Driver.ResizeBuffersMESA( ctx );
 373 }