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 GL_SGI_color_matrix
  83         Adds a color matrix and another set of scale and bias parameters
  84         to the glDraw/CopyPixels paths.
  85
  86 GL_SGI_color_table
  87         Adds additional color tables to the glDraw/Read/CopyPixels paths.
  88
  89 GL_EXT_histogram
  90         Compute histograms for glDraw/Read/CopyPixels.
  91
  92
  93
  94 GLX_SGI_make_current_read functionality
  95 ---------------------------------------
  96
  97 The functionality of this extension is needed for GLX 1.3 (and required
  98 for the Linux/OpenGL standards base).
  99
 100 Implementing this function required a **DEVICE DRIVER CHANGE**.
 101 The old SetBuffer() function has been replaced by SetReadBuffer() and
 102 SetDrawBuffer().  All device drivers will have to be updated because
 103 of this change.
 104
 105 The new function, glXMakeContextCurrent(), in GLX 1.3 now works in Mesa.
 106 The xdemos/wincopy.c program demonstrates it.
 107
 108
 109
 110 Image-related code changes
 111 --------------------------
 112
 113 The imaging path code used by glDrawPixels, glTexImage[123]D,
 114 glTexSubImage[123], etc has been rewritten.  It's now faster,
 115 uses less memory and has several bug fixes.  This work was
 116 actually started in Mesa 3.1 with the glTexImage paths but has now
 117 been carried over to glDrawPixels as well.
 118
 119
 120
 121 Device driver interface changes
 122 -------------------------------
 123
 124 Added new functions for hardware stencil buffer support:
 125    WriteStencilSpan
 126    ReadStencilSpan
 127    WriteStencilPixels
 128    ReadStencilPixels
 129
 130
 131 Removed old depth buffer functions:
 132    AllocDepthBuffer
 133    DepthTestSpan
 134    DepthTestPixels
 135    ReadDepthSpanFloat
 136    ReadDepthSpanInt
 137
 138
 139 Added new depth buffer functions:
 140    WriteDepthSpan
 141    ReadDepthSpan
 142    WriteDepthPixels
 143    ReadDepthPixels
 144
 145    These functions always read/write 32-bit GLuints.  This will allow
 146    drivers to have anywhere from 0 to 32-bit Z buffers without
 147    recompiling for 16 vs 32 bits as was previously needed.
 148
 149
 150 New texture image functions
 151    The entire interface for texture image specification has been updated.
 152    With the new functions, it's optional for Mesa to keep an internal copy
 153    of all textures.  Texture download should be a lot faster when the extra
 154    copy isn't made.
 155
 156 Misc changes
 157    TexEnv now takes a target argument
 158    Removed UseGlobalTexturePalette (use Enable function instead)
 159
 160
 161 Also added
 162    ReadPixels
 163    CopyPixels
 164
 165
 166 The SetBufffer function has been replaced by SetDrawBuffer and
 167 SetReadBuffer functions.  This lets core Mesa independently
 168 specify which buffer is to be used for reading and which for
 169 drawing.
 170
 171 The Clear function's mask parameter has changed.  Instead of
 172 mask being the flags specified by the user to glClear, the
 173 mask is now a bitmask of the DD_*_BIT flags in dd.h.  Now
 174 multiple color buffers can be specified for clearing (ala
 175 glDrawBuffers).  The driver's Clear function must also
 176 check the glColorMask glIndexMask, and glStencilMask settings
 177 and do the right thing.  See the X/Mesa, OS/Mesa, or FX/Mesa
 178 drivers for examples.
 179
 180
 181 The depth buffer changes shouldn't be hard to make for existing
 182 drivers.  In fact, it should simply the code.  Be careful with
 183 the depthBits value passed to gl_create_context().  1 is a bad
 184 value!  It should normally be 0, 16, 24, or 32.
 185
 186
 187 gl_create_framebuffer() takes new arguments which explicitly tell
 188 core Mesa which ancillary buffers (depth, stencil, accum, alpha)
 189 should be implemented in software.  Mesa hardware drivers should
 190 carefully set these flags depending on which buffers are in the
 191 graphics card.
 192
 193
 194
 195 Internal constants
 196 ------------------
 197
 198 Point and line size range and granularity limits are now stored
 199 in the gl_constants struct, which is the Const member of GLcontext.
 200 The limits are initialized from values in config.h but may be
 201 overridden by device drivers to reflect the limits of that driver's
 202 hardware.
 203
 204 Also added constants for NumAuxBuffers and SubPixelBits.
 205
 206
 207
 208
 209 ----------------------------------------------------------------------
 210 $Id: RELNOTES-3.3,v 1.4 2000/05/04 13:50:33 brianp Exp $