cmgui environment variables

While we used to use a Cmgui file for configuring CMGUI in the past, this X

mechanism was only supported by Motif versions. We have not implemented anything new for cross platform configuration and are relying on a few environment variables where options are available but not normally used by users. Note that these variables are also relevant to Zinc but you will need to run firefox from a terminal rather than by clicking on an icon.

Examples:

CMISS_EXAMPLES Specify where the top level of your cmiss examples are found.

If this correctly points to a cmiss example tree then you will be able to run cmgui examples with the 'cmgui -example a/a1' notation.

For the perl interpreter:

CMISS_PERL Specify the perl executable that you want to use the library

installation from. CMISS (both cm and CMGUI) try to allow you to use already installed libraries from this executable.

CMISS_PERLLIB Specifies a colon separated list of

paths which will be prepended to the list of directories

in which to search for Perl library files.

This is commonly used to include some standard perl modules related to cmiss and consequently if none of these variables are set and CMISS_ROOT is set then the directory '${CMISS_ROOT}/cmiss_perl/lib' is added automatically.

For textures

CMISS_MAX_TEXTURE_SIZE Override the max texture size as specified by

OpenGL. This enables you to work around a faulty OpenGL driver, either when the max texture size is smaller or larger that what actually works by you specifying a different value.

CMISS_MAX_3D_TEXTURE_SIZE Override the max 3D texture size as specified by

OpenGL. This enables you to work around a faulty OpenGL driver, either when the max texture size is smaller or larger that what actually works by you specifying a different value.

Open GL extensions

It is useful for testing and development to be able to override the settings of OpenGL extensions. Various OpenGL extensions can be enabled or disabled by the use of environment variables. This can come in handy if your drivers incorrectly report something doesn't work that does, or vice versa. The extensions are enabled or disabled using an environment variable of the same name as the extension with a CMISS_ prefix,

eg. CMISS_GL_display_lists

If the value is 0 or not a number then the behaviour is as if the extension is not available. If the value is 1 then cmgui will behave as if the extension is available. Here is a list of the variables you can use to enable/disable the corresponding extensions.

CMISS_GL_ARB_draw_buffers

CMISS_GL_ARB_texture_float

CMISS_GL_ARB_fragment_program

CMISS_GL_ARB_vertex_program

CMISS_GL_ARB_vertex_buffer_object

CMISS_GL_ARB_texture_non_power_of_two

CMISS_GL_ATI_texture_float

CMISS_GL_EXT_vertex_array

CMISS_GL_NV_float_buffer

CMISS_GL_SGIS_generate_mipmap

CMISS_GL_display_lists

CMISS_GL_shading_language