text: /*
   * Mesa 3-D graphics library
   * Version:  7.1
   *
   * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included
   * in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
   * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   */
  
  /**
   * \file pixelstore.c
   * glPixelStore functions.
   */
  
  
  #include "glheader.h"
  #include "bufferobj.h"
  #include "context.h"
  #include "pixelstore.h"
  #include "mfeatures.h"
  #include "mtypes.h"
  
  
  void GLAPIENTRY
  _mesa_PixelStorei( GLenum pname, GLint param )
  {
     /* NOTE: this call can't be compiled into the display list */
     GET_CURRENT_CONTEXT(ctx);
     ASSERT_OUTSIDE_BEGIN_END(ctx);
  
     switch (pname) {
        case GL_PACK_SWAP_BYTES:
           if (!_mesa_is_desktop_gl(ctx))
              goto invalid_enum_error;
  	 if (param == (GLint)ctx->Pack.SwapBytes)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
           ctx->Pack.SwapBytes = param ? GL_TRUE : GL_FALSE;
  	 break;
        case GL_PACK_LSB_FIRST:
           if (!_mesa_is_desktop_gl(ctx))
              goto invalid_enum_error;
  	 if (param == (GLint)ctx->Pack.LsbFirst)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
           ctx->Pack.LsbFirst = param ? GL_TRUE : GL_FALSE;
  	 break;
        case GL_PACK_ROW_LENGTH:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.RowLength == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.RowLength = param;
  	 break;
        case GL_PACK_IMAGE_HEIGHT:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
           if (param<0) {
              _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.ImageHeight == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.ImageHeight = param;
           break;
        case GL_PACK_SKIP_PIXELS:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.SkipPixels == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.SkipPixels = param;
  	 break;
        case GL_PACK_SKIP_ROWS:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.SkipRows == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.SkipRows = param;
  	 break;
        case GL_PACK_SKIP_IMAGES:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.SkipImages == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.SkipImages = param;
  	 break;
        case GL_PACK_ALIGNMENT:
           if (param!=1 && param!=2 && param!=4 && param!=8) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Pack.Alignment == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Pack.Alignment = param;
  	 break;
        case GL_PACK_INVERT_MESA:
           if (!_mesa_is_desktop_gl(ctx))
              goto invalid_enum_error;
           if (!ctx->Extensions.MESA_pack_invert) {
              _mesa_error( ctx, GL_INVALID_ENUM, "glPixelstore(pname)" );
              return;
           }
           if (ctx->Pack.Invert == param)
              return;
           FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
           ctx->Pack.Invert = param;
           break;
  
        case GL_UNPACK_SWAP_BYTES:
           if (!_mesa_is_desktop_gl(ctx))
              goto invalid_enum_error;
  	 if (param == (GLint)ctx->Unpack.SwapBytes)
  	    return;
  	 if ((GLint)ctx->Unpack.SwapBytes == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.SwapBytes = param ? GL_TRUE : GL_FALSE;
           break;
        case GL_UNPACK_LSB_FIRST:
           if (!_mesa_is_desktop_gl(ctx))
              goto invalid_enum_error;
  	 if (param == (GLint)ctx->Unpack.LsbFirst)
  	    return;
  	 if ((GLint)ctx->Unpack.LsbFirst == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.LsbFirst = param ? GL_TRUE : GL_FALSE;
  	 break;
        case GL_UNPACK_ROW_LENGTH:
           if (ctx->API == API_OPENGLES)
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Unpack.RowLength == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.RowLength = param;
  	 break;
        case GL_UNPACK_IMAGE_HEIGHT:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
           if (param<0) {
              _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Unpack.ImageHeight == param)
  	    return;
  
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.ImageHeight = param;
           break;
        case GL_UNPACK_SKIP_PIXELS:
           if (ctx->API == API_OPENGLES)
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Unpack.SkipPixels == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.SkipPixels = param;
  	 break;
        case GL_UNPACK_SKIP_ROWS:
           if (ctx->API == API_OPENGLES)
              goto invalid_enum_error;
  	 if (param<0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Unpack.SkipRows == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.SkipRows = param;
  	 break;
        case GL_UNPACK_SKIP_IMAGES:
           if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
              goto invalid_enum_error;
  	 if (param < 0) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore(param)" );
  	    return;
  	 }
  	 if (ctx->Unpack.SkipImages == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.SkipImages = param;
  	 break;
        case GL_UNPACK_ALIGNMENT:
           if (param!=1 && param!=2 && param!=4 && param!=8) {
  	    _mesa_error( ctx, GL_INVALID_VALUE, "glPixelStore" );
  	    return;
  	 }
  	 if (ctx->Unpack.Alignment == param)
  	    return;
  	 FLUSH_VERTICES(ctx, _NEW_PACKUNPACK);
  	 ctx->Unpack.Alignment = param;
  	 break;
        default:
           goto invalid_enum_error;
     }
  
     return;
  
  invalid_enum_error:
     _mesa_error( ctx, GL_INVALID_ENUM, "glPixelStore" );
     return;
  }
  
  
  void GLAPIENTRY
  _mesa_PixelStoref( GLenum pname, GLfloat param )
  {
     _mesa_PixelStorei( pname, IROUND(param) );
  }
  
  
  
  /**
   * Initialize the context's pixel store state.
   */
  void
  _mesa_init_pixelstore( struct gl_context *ctx )
  {
     /* Pixel transfer */
     ctx->Pack.Alignment = 4;
     ctx->Pack.RowLength = 0;
     ctx->Pack.ImageHeight = 0;
     ctx->Pack.SkipPixels = 0;
     ctx->Pack.SkipRows = 0;
     ctx->Pack.SkipImages = 0;
     ctx->Pack.SwapBytes = GL_FALSE;
     ctx->Pack.LsbFirst = GL_FALSE;
     ctx->Pack.Invert = GL_FALSE;
  #if FEATURE_EXT_pixel_buffer_object
     _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj,
                                   ctx->Shared->NullBufferObj);
  #endif
     ctx->Unpack.Alignment = 4;
     ctx->Unpack.RowLength = 0;
     ctx->Unpack.ImageHeight = 0;
     ctx->Unpack.SkipPixels = 0;
     ctx->Unpack.SkipRows = 0;
     ctx->Unpack.SkipImages = 0;
     ctx->Unpack.SwapBytes = GL_FALSE;
     ctx->Unpack.LsbFirst = GL_FALSE;
     ctx->Unpack.Invert = GL_FALSE;
  #if FEATURE_EXT_pixel_buffer_object
     _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj,
                                   ctx->Shared->NullBufferObj);
  #endif
  
     /*
      * _mesa_unpack_image() returns image data in this format.  When we
      * execute image commands (glDrawPixels(), glTexImage(), etc) from
      * within display lists we have to be sure to set the current
      * unpacking parameters to these values!
      */
     ctx->DefaultPacking.Alignment = 1;
     ctx->DefaultPacking.RowLength = 0;
     ctx->DefaultPacking.SkipPixels = 0;
     ctx->DefaultPacking.SkipRows = 0;
     ctx->DefaultPacking.ImageHeight = 0;
     ctx->DefaultPacking.SkipImages = 0;
     ctx->DefaultPacking.SwapBytes = GL_FALSE;
     ctx->DefaultPacking.LsbFirst = GL_FALSE;
     ctx->DefaultPacking.Invert = GL_FALSE;
  #if FEATURE_EXT_pixel_buffer_object
     _mesa_reference_buffer_object(ctx, &ctx->DefaultPacking.BufferObj,
                                   ctx->Shared->NullBufferObj);
  #endif
  }
  