From a0c4815433ccd57322f4f7703ca35e9ccfa59250 Mon Sep 17 00:00:00 2001 From: marha Date: Thu, 8 Oct 2009 13:15:52 +0000 Subject: Added MesaLib-7.6 --- mesalib/docs/osmesa.html | 88 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 mesalib/docs/osmesa.html (limited to 'mesalib/docs/osmesa.html') diff --git a/mesalib/docs/osmesa.html b/mesalib/docs/osmesa.html new file mode 100644 index 000000000..629d054f4 --- /dev/null +++ b/mesalib/docs/osmesa.html @@ -0,0 +1,88 @@ + + +Off-screen Rendering + + + + + +

Off-screen Rendering

+ + +

+Mesa's off-screen rendering interface is used for rendering into +user-allocated blocks of memory. +That is, the GL_FRONT colorbuffer is actually a buffer in main memory, +rather than a window on your display. +There are no window system or operating system dependencies. +One potential application is to use Mesa as an off-line, batch-style renderer. +

+ +

+The OSMesa API provides three basic functions for making off-screen +renderings: OSMesaCreateContext(), OSMesaMakeCurrent(), and +OSMesaDestroyContext(). See the Mesa/include/GL/osmesa.h header for +more information about the API functions. +

+ +

+There are several examples of OSMesa in the progs/osdemo/ +directory. +

+ + +

Deep color channels

+ +

+For some applications 8-bit color channels don't have sufficient +precision. +OSMesa supports 16-bit and 32-bit color channels through the OSMesa interface. +When using 16-bit channels, channels are GLushorts and RGBA pixels occupy +8 bytes. +When using 32-bit channels, channels are GLfloats and RGBA pixels occupy +16 bytes. +

+ +

+Before version 6.5.1, Mesa had to be recompiled to support exactly +one of 8, 16 or 32-bit channels. +With Mesa 6.5.1, Mesa can be compiled for either 8, 16 or 32-bit channels +and render into any of the smaller size channels. +For example, if Mesa's compiled for 32-bit channels, you can also render +16 and 8-bit channel images. +

+ +

+To build Mesa/OSMesa for 16 and 8-bit color channel support: +

+      make realclean
+      make linux-osmesa16
+
+ +

+To build Mesa/OSMesa for 32, 16 and 8-bit color channel support: +

+      make realclean
+      make linux-osmesa32
+
+ +

+You'll wind up with a library named libOSMesa16.so or libOSMesa32.so. +Otherwise, most Mesa configurations build an 8-bit/channel libOSMesa.so library +by default. +

+ +

+If performance is important, compile Mesa for the channel size you're +most interested in. +

+ +

+If you need to compile on a non-Linux platform, copy Mesa/configs/linux-osmesa16 +to a new config file and edit it as needed. Then, add the new config name to +the top-level Makefile. Send a patch to the Mesa developers too, if you're +inclined. +

+ + + -- cgit v1.2.3