1. Layout of the nvidia-settings GUI

2. How OpenGL Interacts with nvidia-settings

3. Loading Settings Automatically

4. Commandline Interface

5. X Display Names in the Config File

6. Connecting to Remote X Servers

7. Licensing

8. TODO

The nvidia-settings GUI is organized with a list of different categories on the left side. Only one entry in the list can be selected at once, and the selected category controls which "page" is displayed on the right side of the nvidia-settings GUI.

The category list is organized in a tree: each X screen contains the relevant subcategories beneath it. Similarly, the Display Devices category for a screen contains all the enabled display devices beneath it. Besides each X screen, the other top level category is "nvidia-settings Configuration", which configures behavior of the nvidia-settings application itself.

Along the bottom of the nvidia-settings GUI, from left to right, is:

1)

a status bar which indicates the most recently altered option;

2)

a Help button that toggles the display of a help window which provides a detailed explanation of the available options in the current page; and

3)

a Quit button to exit nvidia-settings.

Most options throughout nvidia-settings are applied immediately. Notable exceptions are OpenGL options which are only read by OpenGL when an OpenGL application starts.

Details about the options on each page of nvidia-settings are available in the help window.

When an OpenGL application starts, it downloads the current values from the X driver, and then reads the environment (see APPENDIX E: OPENGL ENVIRONMENT VARIABLE SETTINGS in the README). Settings from the X server override OpenGL's default values, and settings from the environment override values from the X server.

For example, by default OpenGL uses the FSAA setting requested by the application (normally, applications do not request any FSAA). An FSAA setting specified in nvidia-settings would override the OpenGL application's request. Similarly, the __GL_FSAA_MODE environment variable will override the application's FSAA setting, as well as any FSAA setting specified in nvidia-settings.

Note that an OpenGL application only retrieves settings from the X server when it starts, so if you make a change to an OpenGL value in nvidia-settings, it will only apply to OpenGL applications which are started after that point in time.

The NVIDIA X driver does not preserve values set with nvidia-settings between runs of the X server (or even between logging in and logging out of X, with xdm(1), gdm, or kdm ). This is intentional, because different users may have different preferences, thus these settings are stored on a per-user basis in a configuration file stored in the user's home directory.

The configuration file is named ~/.nvidia-settings-rc. You can specify a different configuration file name with the --config commandline option.

After you have run nvidia-settings once and have generated a configuration file, you can then run: nvidia-settings --load-config-only at any time in the future to upload these settings to the X server again. For example, you might place the above command in your ~/.xinitrc file so that your settings are applied automatically when you log in to X.

Your .xinitrc file, which controls what X applications should be started when you log into X (or startx), might look something like this:

nvidia-settings --load-config-only & xterm & evilwm

or:

nvidia-settings --load-config-only & gnome-session

If you do not already have an ~/.xinitrc file, then chances are that xinit(1) is using a system-wide xinitrc file. This system wide file is typically here:

/etc/X11/xinit/xinitrc

To use it, but also have nvidia-settings upload your settings, you could create an ~/.xinitrc with the contents:

nvidia-settings --load-config-only & . /etc/X11/xinit/xinitrc

System administrators may choose to place the nvidia-settings load command directly in the system xinitrc script.

Please see the xinit(1) man page for further details of configuring your ~/.xinitrc file.

nvidia-settings has a rich commandline interface: all attributes that can be manipulated with the GUI can also be queried and set from the command line. The commandline syntax for querying and assigning attributes matches that of the .nvidia-settings-rc configuration file.

The --query option can be used to query the current value of attributes. This will also report the valid values for the attribute. You can run nvidia-settings --query all for a complete list of available attributes, what the current value is, what values are valid for the attribute, and through which target types (e.g., X screens, GPUs) the attributes can be addressed. Additionally, individual attributes may be specified like this:

nvidia-settings --query CursorShadow

Attributes that may differ per display device (for example, DigitalVibrance can be set independently on each display device when in TwinView) can be appended with a "display device name" within brackets; e.g.:

nvidia-settings --query DigitalVibrance[CRT-0]

If an attribute is display device specific, but the query does not specify a display device, then the attribute value for all display devices will be queried.

An attribute name may be prepended with an X Display name and a forward slash to indicate a different X Display; e.g.:

nvidia-settings --query localhost:0.0/DigitalVibrance[DFP-1]

An attribute name may also just be prepended with the screen number and a forward slash:

nvidia-settings --query 0/DigitalVibrance[DFP-1]

in which case the default X Display will be used, but you can indicate to which X screen to direct the query (if your X server has multiple X screens). If no X screen is specified, then the attribute value will be queried for all X screens.

Attributes can be addressed through "target types". A target type indicates the object that is queried when you query an attribute. The default target type is an X screen, but other possible target types are GPUs and Frame Lock devices.

Target types give you different granularities with which to perform queries and assignments. Since X screens can span multiple GPUs (in the case of Xinerama, or SLI), and multiple X screens can exist on the same GPU, it is sometimes useful to address attributes by GPU rather than X screen.

A target specification is contained within brackets and consists of a target type name, a colon, and the target id. The target type name can be one of screen, gpu, or framelock; the target id is the index into the list of targets (for that target type). Target specifications can be used wherever an X screen is used in query and assignment commands; the target specification can be used either by itself on the left side of the forward slash, or as part of an X Display name.

For example, the following queries address X screen 0 on the localhost:

nvidia-settings --query 0/VideoRam nvidia-settings --query localhost:0.0/VideoRam nvidia-settings --query [screen:0]/VideoRam nvidia-settings --query localhost:0[screen:0]/VideoRam

To address GPU 0 instead, you can use either of:

nvidia-settings --query [gpu:0]/VideoRam nvidia-settings --query localhost:0[gpu:0]/VideoRam

See the output of

nvidia-settings --query all

for what targets types can be used with each attribute. See the output of

nvidia-settings --query screens --query gpus --query framelocks

for lists of targets for each target type.

The --assign option can be used to assign a new value to an attribute. The valid values for an attribute are reported when the attribute is queried. The syntax for --assign is the same as --query, with the additional requirement that assignments also have an equal sign and the new value. For example:

nvidia-settings --assign FSAA=2 nvidia-settings --assign 0/DigitalVibrance[CRT-1]=9 nvidia-settings --assign [gpu:0]/DigitalVibrance=0

Multiple queries and assignments may be specified on the commandline for a single invocation of nvidia-settings.

If either the --query or --assign options are passed to nvidia-settings, the GUI will not be presented, and nvidia-settings will exit after processing the assignments and/or queries.

In the Commandline Interface section above, it was noted that you can specify an attribute without any X Display qualifiers, with only an X screen qualifier, or with a full X Display name. For example:

nvidia-settings --query FSAA nvidia-settings --query 0/FSAA nvidia-settings --query stravinsky.nvidia.com:0/FSAA

In the first two cases, the default X Display will be used, in the second case, the screen from the default X Display can be overridden, and in the third case, the entire default X Display can be overridden.

The same possibilities are available in the ~/.nvidia-settings-rc configuration file.

For example, in a computer lab environment, you might log into any of multiple workstations, and your home directory is NFS mounted to each workstation. In such a situation, you might want your ~/.nvidia-settings-rc file to be applicable to all the workstations. Therefore, you would not want your config file to qualify each attribute with an X Display Name. Leave the "Include X Display Names in the Config File" option unchecked on the nvidia-settings Configuration page (this is the default).

There may be cases when you do want attributes in the config file to be qualified with the X Display name. If you know what you are doing and want config file attributes to be qualified with an X Display, check the "Include X Display Names in the Config File" option on the nvidia-settings Configuration page.

In the typical home user environment where your home directory is local to one computer and you are only configuring one X Display, then it does not matter whether each attribute setting is qualified with an X Display Name.

nvidia-settings is an X client, but uses two separate X connections: one to display the GUI, and another to communicate the NV-CONTROL requests. These two X connections do not need to be to the same X server. For example, you might run nvidia-settings on the computer stravinsky.nvidia.com, export the display to the computer bartok.nvidia.com, but be configuring the X server on the computer schoenberg.nvidia.com:

nvidia-settings --display=bartok.nvidia.com:0 \ --ctrl-display=schoenberg.nvidia.com:0

If --ctrl-display is not specified, then the X Display to control is what --display indicates. If --display is also not specified, then the $DISPLAY environment variable is used.

Note, however, that you will need to have X permissions configured such that you can establish an X connection from the computer on which you are running nvidia-settings (stravinsky.nvidia.com) to the computer where you are displaying the GUI (bartok.nvidia.com) and the computer whose X Display you are configuring (schoenberg.nvidia.com).

The simplest, most common, and least secure mechanism to do this is to use 'xhost' to allow access from the computer on which you are running nvidia-settings.

(issued from bartok.nvidia.com) xhost +stravinsky.nvidia.com

(issued from schoenberg.nvidia.com) xhost +stravinsky.nvidia.com

This will allow all X clients run on stravinsky.nvidia.com to connect and display on bartok.nvidia.com's X server and configure schoenberg.nvidia.com's X server.

Please see the xauth(1) and xhost(1) man pages, or refer to your system documentation on remote X applications and security. You might also Google for terms such as "remote X security" or "remote X Windows", and see documents such as the Remote X Apps mini-HOWTO: Please also note that the remote X server to be controlled must be using the NVIDIA X driver.

The source code to nvidia-settings is released as GPL. The most recent official version of the source code is available here: Note that nvidia-settings is simply an NV-CONTROL client. It uses the NV-CONTROL X extension to communicate with the NVIDIA X server to query current settings and make changes to settings.

You can make additions directly to nvidia-settings, or write your own NV-CONTROL client, using nvidia-settings as an example.

Documentation on the NV-CONTROL extension and additional sample clients are available in the nvidia-settings source tarball. Patches can be submitted to linux-bugs@nvidia.com.

There are many things still to be added to nvidia-settings, some of which include:

-

configurability of TwinView (NVIDIA is planning to implement this)

-

configurability of multiple X screens (NVIDIA is planning to implement this)

-

different toolkits? The GUI for nvidia-settings is cleanly abstracted from the backend of nvidia-settings that parses the configuration file and commandline, communicates with the X server, etc. If someone were so inclined, a different frontend GUI could be implemented.

-

write a design document explaining how nvidia-settings is architected; presumably this would make it easier for people to become familiar with the code base.

If there are other things you would like to see added (or better yet, would like to add yourself), please contact linux-bugs@nvidia.com.