docs/perf.html

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  10 <h1>Performance Tips</h1>
  11
  12 <p>
  13 Performance tips for software rendering:
  14 </p>
  15 <ol>
  16
  17 <li> Turn off smooth shading when you don't need it (glShadeModel)
  18 <li> Turn off depth buffering when you don't need it.
  19 <li> Turn off dithering when not needed.
  20 <li> Use double buffering as it's often faster than single buffering
  21 <li> Compile in the X Shared Memory extension option if it's supported
  22       on your system by adding -DSHM to CFLAGS and -lXext to XLIBS for
  23       your system in the Make-config file.
  24 <li> Recompile Mesa with more optimization if possible.
  25 <li> Try to maximize the amount of drawing done between glBegin/glEnd pairs.
  26 <li> Use the MESA_BACK_BUFFER variable to find best performance in double
  27       buffered mode.  (X users only)
  28 <li> Optimized polygon rasterizers are employed when:
  29          rendering into back buffer which is an XImage
  30          RGB mode, not grayscale, not monochrome
  31          depth buffering is GL_LESS, or disabled
  32          flat or smooth shading
  33          dithered or non-dithered
  34          no other rasterization operations enabled (blending, stencil, etc)
  35 <li> Optimized line drawing is employed when:
  36          rendering into back buffer which is an XImage
  37          RGB mode, not grayscale, not monochrome
  38          depth buffering is GL_LESS or disabled
  39          flat shading
  40          dithered or non-dithered
  41          no other rasterization operations enabled (blending, stencil, etc)
  42 <li> Textured polygons are fastest when:
  43          using a 3-component (RGB), 2-D texture
  44          minification and magnification filters are GL_NEAREST
  45          texture coordinate wrap modes for S and T are GL_REPEAT
  46          GL_DECAL environment mode
  47          glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST )
  48          depth buffering is GL_LESS or disabled
  49 <li> Lighting is fastest when:
  50          Two-sided lighting is disabled
  51          GL_LIGHT_MODEL_LOCAL_VIEWER is false
  52          GL_COLOR_MATERIAL is disabled
  53          No spot lights are used (all GL_SPOT_CUTOFFs are 180.0)
  54          No local lights are used (all position W's are 0.0)
  55          All material and light coefficients are &gt;= zero
  56 <li> XFree86 users:  if you want to use 24-bit color try starting your
  57       X server in 32-bit per pixel mode for better performance.  That is,
  58       start your X server with
  59          startx -- -bpp 32
  60       instead of
  61          startx -- -bpp 24
  62 <li> Try disabling dithering with the MESA_NO_DITHER environment variable.
  63       If this env var is defined Mesa will disable dithering and the
  64       command glEnable(GL_DITHER) will be ignored.
  65 </ol>
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