docs/RELNOTES-3.3

   1
   2                          Mesa 3.3 release notes
   3
   4                              PLEASE READ!!!!
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   6
   7
   8
   9 Header file / GLenum changes
  10 ----------------------------
  11
  12 The gl.h and glu.h headers now use #defines to define all GL_* tokens
  13 instead of C-language enums.  This change improves Mesa/OpenGL
  14 interoperability.
  15
  16
  17
  18 New API dispatch code
  19 ---------------------
  20
  21 The core Mesa gl* functions are now implemented with a new dispatch
  22 (jump table) which will allow simultaneous direct/indirect rendering.
  23
  24 The code is found in the glapi*.[ch] files.
  25
  26 Of interest:  the actual "glFooBar" functions are generated with
  27 templatized code defined in glapitemp.h and included by glapi.c
  28 The glapitemp.h template should be reusable for all sorts of OpenGL
  29 projects.
  30
  31
  32 New thread support
  33 ------------------
  34
  35 Thread support in Mesa has been rewritten.  The glthread.[ch] files
  36 replace mthreads.[ch].  Thread safety is always enabled (on platforms
  37 which support threads, that is).  There is virtually no performance
  38 penalty for typical single-thread applications.  See the glapi.c
  39 file for details.
  40
  41
  42
  43 Make configuration changes
  44 --------------------------
  45
  46 If you use the old-style (non GNU automake) method to build Mesa note
  47 that several of the configuration names have changed:
  48
  49    Old name        New name
  50    -------------   ----------------
  51    linux-elf       linux
  52    linux           linux-static
  53    linux-386-elf   linux-386
  54    linux-386       linux-386-static
  55    etc.
  56
  57
  58
  59 New extensions
  60 --------------
  61
  62 GL_EXT_transpose_matrix
  63         Adds glLoadTransposeMatrix() and glMultTransposeMatrix() functions.
  64         See http://reality.sgi.com/opengl/arb/extensions/ext_text/GL_EXT_transpose_matrix.txt
  65
  66 GL_EXT_texture_add_env
  67         Adds GL_ADD texture environment mode.
  68         See http://www.berkelium.com/OpenGL/EXT/texture_env_add.txt
  69
  70 GL_EXT_texture_lod_bias
  71         Allows mipmapped texture blurring and sharpening.
  72
  73 GLX_EXT_visual_rating extension
  74         This extension has no effect in stand-alone Mesa (used for DRI).
  75
  76 GL_HP_occlusion_test
  77         Used for bounding box occlusion testing (see demos/occlude.c).
  78
  79 GL_SGIX_pixel_texture / GL_SGIS_pixel_texture
  80         Lets glDraw/CopyPixels draw a texture coordinate image
  81
  82
  83
  84 GLX_SGI_make_current_read functionality
  85 ---------------------------------------
  86
  87 The functionality of this extension is needed for GLX 1.3 (and required
  88 for the Linux/OpenGL standards base).
  89
  90 Implementing this function required a **DEVICE DRIVER CHANGE**.
  91 The old SetBuffer() function has been replaced by SetReadBuffer() and
  92 SetDrawBuffer().  All device drivers will have to be updated because
  93 of this change.
  94
  95 The new function, glXMakeContextCurrent(), in GLX 1.3 now works in Mesa.
  96 The xdemos/wincopy.c program demonstrates it.
  97
  98
  99
 100 Image-related code changes
 101 --------------------------
 102
 103 The imaging path code used by glDrawPixels, glTexImage[123]D,
 104 glTexSubImage[123], etc has been rewritten.  It's now faster,
 105 uses less memory and has several bug fixes.  This work was
 106 actually started in Mesa 3.1 with the glTexImage paths but has now
 107 been carried over to glDrawPixels as well.
 108
 109
 110
 111 Device driver interface changes
 112 -------------------------------
 113
 114 Added new functions for hardware stencil buffer support:
 115    WriteStencilSpan
 116    ReadStencilSpan
 117    WriteStencilPixels
 118    ReadStencilPixels
 119
 120
 121 Removed old depth buffer functions:
 122    AllocDepthBuffer
 123    DepthTestSpan
 124    DepthTestPixels
 125    ReadDepthSpanFloat
 126    ReadDepthSpanInt
 127
 128
 129 Added new depth buffer functions:
 130    WriteDepthSpan
 131    ReadDepthSpan
 132    WriteDepthPixels
 133    ReadDepthPixels
 134
 135    These functions always read/write 32-bit GLuints.  This will allow
 136    drivers to have anywhere from 0 to 32-bit Z buffers without
 137    recompiling for 16 vs 32 bits as was previously needed.
 138
 139
 140 New texture image functions
 141    The entire interface for texture image specification has been updated.
 142    With the new functions, it's optional for Mesa to keep an internal copy
 143    of all textures.  Texture download should be a lot faster when the extra
 144    copy isn't made.
 145
 146 Misc changes
 147    TexEnv now takes a target argument
 148    Removed UseGlobalTexturePalette (use Enable function instead)
 149
 150
 151 Also added
 152    ReadPixels
 153    CopyPixels
 154
 155
 156 The SetBufffer function has been replaced by SetDrawBuffer and
 157 SetReadBuffer functions.  This lets core Mesa independently
 158 specify which buffer is to be used for reading and which for
 159 drawing.
 160
 161 The Clear function's mask parameter has changed.  Instead of
 162 mask being the flags specified by the user to glClear, the
 163 mask is now a bitmask of the DD_*_BIT flags in dd.h.  Now
 164 multiple color buffers can be specified for clearing (ala
 165 glDrawBuffers).  The driver's Clear function must also
 166 check the glColorMask glIndexMask, and glStencilMask settings
 167 and do the right thing.  See the X/Mesa, OS/Mesa, or FX/Mesa
 168 drivers for examples.
 169
 170
 171 The depth buffer changes shouldn't be hard to make for existing
 172 drivers.  In fact, it should simply the code.  Be careful with
 173 the depthBits value passed to gl_create_context().  1 is a bad
 174 value!  It should normally be 0, 16, 24, or 32.
 175
 176
 177 gl_create_framebuffer() takes new arguments which explicitly tell
 178 core Mesa which ancillary buffers (depth, stencil, accum, alpha)
 179 should be implemented in software.  Mesa hardware drivers should
 180 carefully set these flags depending on which buffers are in the
 181 graphics card.
 182
 183
 184
 185 Internal constants
 186 ------------------
 187
 188 Point and line size range and granularity limits are now stored
 189 in the gl_constants struct, which is the Const member of GLcontext.
 190 The limits are initialized from values in config.h but may be
 191 overridden by device drivers to reflect the limits of that driver's
 192 hardware.
 193
 194 Also added constants for NumAuxBuffers and SubPixelBits.
 195
 196
 197
 198
 199 ----------------------------------------------------------------------
 200 $Id: RELNOTES-3.3,v 1.1 2000/04/07 17:07:32 brianp Exp $