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10<h1>Performance Tips</h1>
11
12<p>
13Performance tips for software rendering:
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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.
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