<HTML> <TITLE>Performance Tips</TITLE> <BODY text="#000000" bgcolor="#55bbff" link="#111188"> <H1>Performance Tips</H1> <p> Performance tips for software rendering: </P> <ol> <li> Turn off smooth shading when you don't need it (glShadeModel) <li> Turn off depth buffering when you don't need it. <li> Turn off dithering when not needed. <li> Use double buffering as it's often faster than single buffering <li> Compile in the X Shared Memory extension option if it's supported on your system by adding -DSHM to CFLAGS and -lXext to XLIBS for your system in the Make-config file. <li> Recompile Mesa with more optimization if possible. <li> Try to maximize the amount of drawing done between glBegin/glEnd pairs. <li> Use the MESA_BACK_BUFFER variable to find best performance in double buffered mode. (X users only) <li> Optimized polygon rasterizers are employed when: rendering into back buffer which is an XImage RGB mode, not grayscale, not monochrome depth buffering is GL_LESS, or disabled flat or smooth shading dithered or non-dithered no other rasterization operations enabled (blending, stencil, etc) <li> Optimized line drawing is employed when: rendering into back buffer which is an XImage RGB mode, not grayscale, not monochrome depth buffering is GL_LESS or disabled flat shading dithered or non-dithered no other rasterization operations enabled (blending, stencil, etc) <li> Textured polygons are fastest when: using a 3-component (RGB), 2-D texture minification and magnification filters are GL_NEAREST texture coordinate wrap modes for S and T are GL_REPEAT GL_DECAL environment mode glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST ) depth buffering is GL_LESS or disabled <li> Lighting is fastest when: Two-sided lighting is disabled GL_LIGHT_MODEL_LOCAL_VIEWER is false GL_COLOR_MATERIAL is disabled No spot lights are used (all GL_SPOT_CUTOFFs are 180.0) No local lights are used (all position W's are 0.0) All material and light coefficients are >= zero <li> XFree86 users: if you want to use 24-bit color try starting your X server in 32-bit per pixel mode for better performance. That is, start your X server with startx -- -bpp 32 instead of startx -- -bpp 24 <li> Try disabling dithering with the MESA_NO_DITHER environment variable. If this env var is defined Mesa will disable dithering and the command glEnable(GL_DITHER) will be ignored. </ol> </BODY> </HTML>