docs/perf.rst

   1 Performance Tips
   2 ================
   3
   4 Performance tips for software rendering:
   5
   6 #. Turn off smooth shading when you don't need it (glShadeModel)
   7 #. Turn off depth buffering when you don't need it.
   8 #. Turn off dithering when not needed.
   9 #. Use double buffering as it's often faster than single buffering
  10 #. Compile in the X Shared Memory extension option if it's supported on
  11    your system by adding -DSHM to CFLAGS and -lXext to XLIBS for your
  12    system in the Make-config file.
  13 #. Recompile Mesa with more optimization if possible.
  14 #. Try to maximize the amount of drawing done between glBegin/glEnd
  15    pairs.
  16 #. Use the MESA_BACK_BUFFER variable to find best performance in double
  17    buffered mode. (X users only)
  18 #. Optimized polygon rasterizers are employed when: rendering into back
  19    buffer which is an XImage RGB mode, not grayscale, not monochrome
  20    depth buffering is GL_LESS, or disabled flat or smooth shading
  21    dithered or non-dithered no other rasterization operations enabled
  22    (blending, stencil, etc)
  23 #. Optimized line drawing is employed when: rendering into back buffer
  24    which is an XImage RGB mode, not grayscale, not monochrome depth
  25    buffering is GL_LESS or disabled flat shading dithered or
  26    non-dithered no other rasterization operations enabled (blending,
  27    stencil, etc)
  28 #. Textured polygons are fastest when: using a 3-component (RGB), 2-D
  29    texture minification and magnification filters are GL_NEAREST texture
  30    coordinate wrap modes for S and T are GL_REPEAT GL_DECAL environment
  31    mode glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST ) depth
  32    buffering is GL_LESS or disabled
  33 #. Lighting is fastest when: Two-sided lighting is disabled
  34    GL_LIGHT_MODEL_LOCAL_VIEWER is false GL_COLOR_MATERIAL is disabled No
  35    spot lights are used (all GL_SPOT_CUTOFFs are 180.0) No local lights
  36    are used (all position W's are 0.0) All material and light
  37    coefficients are >= zero
  38 #. XFree86 users: if you want to use 24-bit color try starting your X
  39    server in 32-bit per pixel mode for better performance. That is,
  40    start your X server with startx -- -bpp 32 instead of startx -- -bpp
  41    24
  42 #. Try disabling dithering with the MESA_NO_DITHER environment variable.
  43    If this env var is defined Mesa will disable dithering and the
  44    command glEnable(GL_DITHER) will be ignored.