docs/envvars.html

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   3 <TITLE>Environment Variables</TITLE>
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   9 <H1>Environment Variables</H1>
  10
  11 <p>
  12 Mesa supports the following environment variables:
  13 </p>
  14 <ul>
  15 <li>MESA_NO_ASM - if set, disables all assembly language optimizations
  16 <li>MESA_NO_MMX - if set, disables Intel MMX optimizations
  17 <li>MESA_NO_3DNOW - if set, disables AMD 3DNow! optimizations
  18 <li>MESA_NO_SSE - if set, disables Intel SSE optimizations
  19 <li>MESA_DEBUG - if set, error messages are printed to stderr.
  20 If the value of MESA_DEBUG is "FP" floating point arithmetic errors will
  21 generate exceptions.
  22 <li>MESA_NO_DITHER - if set, disables dithering, overriding glEnable(GL_DITHER)
  23 <li>MESA_TEX_PROG - if set, implement conventional texture env modes with
  24 fragment programs (intended for developers only)
  25 <li>MESA_TNL_PROG - if set, implement conventional vertex transformation
  26 operations with vertex programs (intended for developers only).
  27 Setting this variable automatically sets the MESA_TEX_PROG variable as well.
  28 <li>MESA_EXTENSION_OVERRIDE - can be used to enable/disable extensions.
  29 A value such as "GL_EXT_foo -GL_EXT_bar" will enable the GL_EXT_foo extension
  30 and disable the GL_EXT_bar extension.
  31 <li>MESA_GLSL - <a href="shading.html#envvars">shading language options</a>
  32 </ul>
  33
  34 <p>
  35 The following are only applicable to the Xlib software driver.
  36 See the <A HREF="xlibdriver.html">Xlib software driver page</A> for details.
  37 </p>
  38 <ul>
  39 <li>MESA_RGB_VISUAL - specifies the X visual and depth for RGB mode
  40 <li>MESA_CI_VISUAL - specifies the X visual and depth for CI mode
  41 <li>MESA_BACK_BUFFER - specifies how to implement the back color buffer,
  42     either "pixmap" or "ximage"
  43 <li>MESA_GAMMA - gamma correction coefficients for red, green, blue channels
  44 <li>MESA_XSYNC - enable synchronous X behavior (for debugging only)
  45 <li>MESA_GLX_FORCE_CI - if set, force GLX to treat 8bpp visuals as CI visuals
  46 <li>MESA_GLX_FX - set to either "fullscreen" for full-screen rendering,
  47   "window" to render into a window, or "disable" to disable the Glide driver.
  48 <li>MESA_GLX_FORCE_ALPHA - if set, forces RGB windows to have an alpha channel.
  49 <li>MESA_GLX_DEPTH_BITS - specifies default number of bits for depth buffer.
  50 <li>MESA_GLX_ALPHA_BITS - specifies default number of bits for alpha channel.
  51 </ul>
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  53
  54 <p>
  55 These environment variables are for the Intel i945/i965 drivers:
  56 </p>
  57 <ul>
  58 <li>INTEL_STRICT_CONFORMANCE - if set to 1, enable sw fallbacks to improve
  59     OpenGL conformance.  If set to 2, always use software rendering.
  60 <li>INTEL_NO_BLIT - if set, disable hardware-accelerated glBitmap,
  61     glCopyPixels, glDrawPixels.
  62 </ul>
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  64
  65 <p>
  66 These environment variables are for the Radeon R300 driver:
  67 </p>
  68 <ul>
  69 <li>R300_NO_TCL - if set, disable hardware-accelerated Transform/Clip/Lighting.
  70 </ul>
  71
  72 <p>
  73 Mesa EGL supports different sets of environment variables.  See the
  74 <a href="egl.html">Mesa EGL</a> page for the details.
  75 </p>
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