Roland Scheidegger
606132b4de
Previously, nothing was said what happens with shift counts exceeding bit width of the values to shift. In theory 3 behaviors are possible: 1) undefined (classic c definition) 2) just shift out all bits (so result is zero, or -1 potentially for ashr) 3) mask the shift count to bit width - 1 API's either require 3) or are ok with 1). In particular, GLSL (as well as a couple uninteresting legacy GL extensions) is happy with undefined, whereas both OpenCL and d3d10 require 3). Consequently, most hw also implements 3). So, for simplicity we just specify that 3) is required rather than saying undefined and then needing state trackers to work around it. Also while here specify shift count as a vector, not scalar. As far as I can tell this was a doc bug, neither state trackers nor drivers used scalar shift count. Reviewed-by: Jose Fonseca <jfonseca@vmware.com>
File: docs/README.WIN32 Last updated: 21 June 2013 Quick Start ----- ----- Windows drivers are build with SCons. Makefiles or Visual Studio projects are no longer shipped or supported. Run scons osmesa mesagdi to build classic mesa Windows GDI drivers; or scons libgl-gdi to build gallium based GDI driver. This will work both with MSVS or Mingw. Windows Drivers ------- ------- At this time, only the gallium GDI driver is known to work. Source code also exists in the tree for other drivers in src/mesa/drivers/windows, but the status of this code is unknown. Recipe ------ Building on windows requires several open-source packages. These are steps that work as of this writing. 1) install python 2.7 2) install scons (latest) 3) install mingw, flex, and bison 4) install libxml2 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs get libxml2-python-2.9.1.win-amd64-py2.7.exe 5) install pywin32 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs get pywin32-218.4.win-amd64-py2.7.exe 6) install git 7) download mesa from git see http://www.mesa3d.org/repository.html 8) run scons General ------- After building, you can copy the above DLL files to a place in your PATH such as $SystemRoot/SYSTEM32. If you don't like putting things in a system directory, place them in the same directory as the executable(s). Be careful about accidentially overwriting files of the same name in the SYSTEM32 directory. The DLL files are built so that the external entry points use the stdcall calling convention. Static LIB files are not built. The LIB files that are built with are the linker import files associated with the DLL files. The si-glu sources are used to build the GLU libs. This was done mainly to get the better tessellator code. If you have a Windows-related build problem or question, please post to the mesa-dev or mesa-users list.