docs/RELNOTES-3.3

   1
   2                          Mesa 3.3 release notes
   3
   4                              PLEASE READ!!!!
   5
   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 GL_ARB_texture_cube_mapping
  99         6-face cube mapping, nicer than sphere mapping
 100
 101 GL_EXT_texture_env_combine
 102         For advanced texture environment effects.
 103
 104
 105 Documentation for all these functions can be found at
 106 http://oss.sgi.com/projects/ogl-sample/registry/
 107
 108
 109
 110 GLX_SGI_make_current_read functionality
 111 ---------------------------------------
 112
 113 The functionality of this extension is needed for GLX 1.3 (and required
 114 for the Linux/OpenGL standards base).
 115
 116 Implementing this function required a **DEVICE DRIVER CHANGE**.
 117 The old SetBuffer() function has been replaced by SetReadBuffer() and
 118 SetDrawBuffer().  All device drivers will have to be updated because
 119 of this change.
 120
 121 The new function, glXMakeContextCurrent(), in GLX 1.3 now works in Mesa.
 122 The xdemos/wincopy.c program demonstrates it.
 123
 124
 125
 126 Image-related code changes
 127 --------------------------
 128
 129 The imaging path code used by glDrawPixels, glTexImage[123]D,
 130 glTexSubImage[123], etc has been rewritten.  It's now faster,
 131 uses less memory and has several bug fixes.  This work was
 132 actually started in Mesa 3.1 with the glTexImage paths but has now
 133 been carried over to glDrawPixels as well.
 134
 135
 136
 137 Device driver interface changes
 138 -------------------------------
 139
 140 Added new functions for hardware stencil buffer support:
 141    WriteStencilSpan
 142    ReadStencilSpan
 143    WriteStencilPixels
 144    ReadStencilPixels
 145
 146
 147 Removed old depth buffer functions:
 148    AllocDepthBuffer
 149    DepthTestSpan
 150    DepthTestPixels
 151    ReadDepthSpanFloat
 152    ReadDepthSpanInt
 153
 154
 155 Added new depth buffer functions:
 156    WriteDepthSpan
 157    ReadDepthSpan
 158    WriteDepthPixels
 159    ReadDepthPixels
 160
 161    These functions always read/write 32-bit GLuints.  This will allow
 162    drivers to have anywhere from 0 to 32-bit Z buffers without
 163    recompiling for 16 vs 32 bits as was previously needed.
 164
 165
 166 New texture image functions
 167    The entire interface for texture image specification has been updated.
 168    With the new functions, it's optional for Mesa to keep an internal copy
 169    of all textures.  Texture download should be a lot faster when the extra
 170    copy isn't made.
 171
 172 Misc changes
 173    TexEnv now takes a target argument
 174    Removed UseGlobalTexturePalette (use Enable function instead)
 175
 176
 177 Also added
 178    ReadPixels
 179    CopyPixels
 180
 181
 182 The SetBufffer function has been replaced by SetDrawBuffer and
 183 SetReadBuffer functions.  This lets core Mesa independently
 184 specify which buffer is to be used for reading and which for
 185 drawing.
 186
 187 The Clear function's mask parameter has changed.  Instead of
 188 mask being the flags specified by the user to glClear, the
 189 mask is now a bitmask of the DD_*_BIT flags in dd.h.  Now
 190 multiple color buffers can be specified for clearing (ala
 191 glDrawBuffers).  The driver's Clear function must also
 192 check the glColorMask glIndexMask, and glStencilMask settings
 193 and do the right thing.  See the X/Mesa, OS/Mesa, or FX/Mesa
 194 drivers for examples.
 195
 196
 197 The depth buffer changes shouldn't be hard to make for existing
 198 drivers.  In fact, it should simply the code.  Be careful with
 199 the depthBits value passed to gl_create_context().  1 is a bad
 200 value!  It should normally be 0, 16, 24, or 32.
 201
 202
 203 gl_create_framebuffer() takes new arguments which explicitly tell
 204 core Mesa which ancillary buffers (depth, stencil, accum, alpha)
 205 should be implemented in software.  Mesa hardware drivers should
 206 carefully set these flags depending on which buffers are in the
 207 graphics card.
 208
 209
 210
 211 Internal constants
 212 ------------------
 213
 214 Point and line size range and granularity limits are now stored
 215 in the gl_constants struct, which is the Const member of GLcontext.
 216 The limits are initialized from values in config.h but may be
 217 overridden by device drivers to reflect the limits of that driver's
 218 hardware.
 219
 220 Also added constants for NumAuxBuffers and SubPixelBits.
 221
 222
 223
 224
 225 ----------------------------------------------------------------------
 226 $Id: RELNOTES-3.3,v 1.7 2000/07/05 16:05:44 brianp Exp $