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_ARB_transpose_matrix
  63         Adds glLoadTransposeMatrixARB() and glMultTransposeMatrixARB()
  64         functions.
  65
  66 GL_ARB_texture_cube_map
  67         For cube-based reflection mapping.
  68
  69 GL_EXT_texture_add_env
  70         Adds GL_ADD texture environment mode.
  71         See http://www.berkelium.com/OpenGL/EXT/texture_env_add.txt
  72
  73 GL_EXT_texture_lod_bias
  74         Allows mipmapped texture blurring and sharpening.
  75
  76 GLX_EXT_visual_rating extension
  77         This extension has no effect in stand-alone Mesa (used for DRI).
  78
  79 GL_HP_occlusion_test
  80         Used for bounding box occlusion testing (see demos/occlude.c).
  81
  82 GL_SGIX_pixel_texture / GL_SGIS_pixel_texture
  83         Lets glDraw/CopyPixels draw a texture coordinate image.
  84
  85 GL_SGI_color_matrix
  86         Adds a color matrix and another set of scale and bias parameters
  87         to the glDraw/CopyPixels paths.
  88
  89 GL_SGI_color_table
  90         Adds additional color tables to the glDraw/Read/CopyPixels paths.
  91
  92 GL_EXT_histogram
  93         Compute histograms for glDraw/Read/CopyPixels.
  94
  95 GL_EXT_blend_func_separate
  96         This is the same as GL_INGR_blend_func_separate.
  97
  98 Documentation for all these functions can be found at
  99 http://oss.sgi.com/projects/ogl-sample/registry/
 100
 101
 102
 103 GLX_SGI_make_current_read functionality
 104 ---------------------------------------
 105
 106 The functionality of this extension is needed for GLX 1.3 (and required
 107 for the Linux/OpenGL standards base).
 108
 109 Implementing this function required a **DEVICE DRIVER CHANGE**.
 110 The old SetBuffer() function has been replaced by SetReadBuffer() and
 111 SetDrawBuffer().  All device drivers will have to be updated because
 112 of this change.
 113
 114 The new function, glXMakeContextCurrent(), in GLX 1.3 now works in Mesa.
 115 The xdemos/wincopy.c program demonstrates it.
 116
 117
 118
 119 Image-related code changes
 120 --------------------------
 121
 122 The imaging path code used by glDrawPixels, glTexImage[123]D,
 123 glTexSubImage[123], etc has been rewritten.  It's now faster,
 124 uses less memory and has several bug fixes.  This work was
 125 actually started in Mesa 3.1 with the glTexImage paths but has now
 126 been carried over to glDrawPixels as well.
 127
 128
 129
 130 Device driver interface changes
 131 -------------------------------
 132
 133 Added new functions for hardware stencil buffer support:
 134    WriteStencilSpan
 135    ReadStencilSpan
 136    WriteStencilPixels
 137    ReadStencilPixels
 138
 139
 140 Removed old depth buffer functions:
 141    AllocDepthBuffer
 142    DepthTestSpan
 143    DepthTestPixels
 144    ReadDepthSpanFloat
 145    ReadDepthSpanInt
 146
 147
 148 Added new depth buffer functions:
 149    WriteDepthSpan
 150    ReadDepthSpan
 151    WriteDepthPixels
 152    ReadDepthPixels
 153
 154    These functions always read/write 32-bit GLuints.  This will allow
 155    drivers to have anywhere from 0 to 32-bit Z buffers without
 156    recompiling for 16 vs 32 bits as was previously needed.
 157
 158
 159 New texture image functions
 160    The entire interface for texture image specification has been updated.
 161    With the new functions, it's optional for Mesa to keep an internal copy
 162    of all textures.  Texture download should be a lot faster when the extra
 163    copy isn't made.
 164
 165 Misc changes
 166    TexEnv now takes a target argument
 167    Removed UseGlobalTexturePalette (use Enable function instead)
 168
 169
 170 Also added
 171    ReadPixels
 172    CopyPixels
 173
 174
 175 The SetBufffer function has been replaced by SetDrawBuffer and
 176 SetReadBuffer functions.  This lets core Mesa independently
 177 specify which buffer is to be used for reading and which for
 178 drawing.
 179
 180 The Clear function's mask parameter has changed.  Instead of
 181 mask being the flags specified by the user to glClear, the
 182 mask is now a bitmask of the DD_*_BIT flags in dd.h.  Now
 183 multiple color buffers can be specified for clearing (ala
 184 glDrawBuffers).  The driver's Clear function must also
 185 check the glColorMask glIndexMask, and glStencilMask settings
 186 and do the right thing.  See the X/Mesa, OS/Mesa, or FX/Mesa
 187 drivers for examples.
 188
 189
 190 The depth buffer changes shouldn't be hard to make for existing
 191 drivers.  In fact, it should simply the code.  Be careful with
 192 the depthBits value passed to gl_create_context().  1 is a bad
 193 value!  It should normally be 0, 16, 24, or 32.
 194
 195
 196 gl_create_framebuffer() takes new arguments which explicitly tell
 197 core Mesa which ancillary buffers (depth, stencil, accum, alpha)
 198 should be implemented in software.  Mesa hardware drivers should
 199 carefully set these flags depending on which buffers are in the
 200 graphics card.
 201
 202
 203
 204 Internal constants
 205 ------------------
 206
 207 Point and line size range and granularity limits are now stored
 208 in the gl_constants struct, which is the Const member of GLcontext.
 209 The limits are initialized from values in config.h but may be
 210 overridden by device drivers to reflect the limits of that driver's
 211 hardware.
 212
 213 Also added constants for NumAuxBuffers and SubPixelBits.
 214
 215
 216
 217
 218 ----------------------------------------------------------------------
 219 $Id: RELNOTES-3.3,v 1.6 2000/05/26 14:45:25 brianp Exp $