The Views Editor

Media in a wide variety of different colour spaces may coexist within the application. The Views editor allow you to specify the desired viewing transform (or LUT) to use by default for a piece of media based on its colour space. This is enabled by the fact that all media in the application is tagged with a colour space identifier. The Views editor controls the list of options in the views menu for each viewport based on the display and the tagged colour space.

The Views editor is initialized from the OCIO config for your project. Making edits in the application makes a copy of part of your config and applies the edits to the copy. From that point on, any changes that happen to the display and view related sections in the original config will not be used unless you reset the Views editor. This may be done by using the Reset Views button in the lower right of the Views editor table. Alternatively, you may Reload the config and click "Yes" to delete your overrides.

Your edits are stored in the project overrides to the config, there is no modification to the source config itself. To reuse your edits, you may export a copy of the OCIO config with updated display and view mapping. Or when creating a new project you may initialize the OCIO config from the project with the edits.

Making any changes in the Views editor will override the following items from the OCIO config:

• The displays section and the views assigned to each display
• The shared_views section
• The viewing_rules section
• The active_displays and active_views lists
• The virtual_display
• The view_transforms section and the default_view_transform

Adjusting the Priority and Visibility of Views

The first column of the table (with the eye icon) allows you to turn specific views on and off. Turning a view off sets its Allowed Displays value to "Viewport Inactive". This means it will no longer show up as an option in the viewport views menu. (This is implemented via a viewing rule rather than removing the view from the active_views list so that it will only be removed from the viewports but remain as an option in the Colour Management tool's View Transform mode.)

Use the Priority Up and Down buttons to move a view up or down in the table. This determines the order of views in the viewport menus. The highest priority view is called the "default view" for a given display and colour space. It is the view that is used by default in viewports and is the view used to calculate thumbnails. Changing the priority moves the position of the view in the config's active_views list.

Assigning Views to Colour Spaces

The Allowed Displays column in the Views editor is what determines which views are shown for a given colour space or group of colour spaces. The available options are taken from the viewing_rules section of the OCIO config. The default config that ships with Flame Family applications contains the following options:

• Any: Use this view with any colour space.
• Any Scene-linear: Use the view with any colour space whose encoding attribute is "scene-linear".
• Any Log: Use the view with any colour space whose encoding attribute is "log".
• Any Data: Use the view with any colour space whose encoding attribute is "data".
• Any Scene-linear or Log: Use the view with any colour space whose encoding attribute is either "scene-linear" or "log".
• Any Video: Use the view with any colour space whose encoding attribute is either "sdr-video" or "hdr-video".
• Normals: Use the view with the colour space "Normals".
• Unknown: Use the view with the colour space "Unknown".
• Viewport Inactive: Never use this view in a viewport.

If your OCIO config has other viewing rules defined, the options you see will be different. By editing the config, you may create rules that are based on the "encoding" attribute of colour spaces and apply to all colour spaces with the listed encodings, or are based on a list of specific colour spaces.

Assigning Views to Displays

The Allowed Displays column controls which displays a given view is used with. The options are:

• Any: The view is used with all displays.
• Any SDR: The view is used with all displays that have a corresponding display colour space with an encoding attribute of "sdr-video". This is typically true for SDR displays.
• Any HDR: The view is used with all displays that have a corresponding display colour space with an encoding attribute of "hdr-video". This is typically true for HDR displays.
• Specific: You may use this sub-menu to assign this view to only be used with a specific display. (Assigning to multiple specific displays is not possible from the Views editor, but may be done by editing the OCIO config file directly.)
• Mixed: This indicates that the view is used with a mix of both SDR and HDR displays but is not used on all displays. This option is not selectable in the editor, but will appear based on how views are mapped to displays in the OCIO config.

Making adjustments to this menu will add or remove shared views from the Views element of specific displays in the config file overrides.

Assigning Looks to Views

The Looks column of the editor allows you to assign an item from the looks section of the OCIO config to a view. (If the config has no looks, there will be no options in the menu.) The "Remove Looks" menu item allows you to remove the looks from the selected view. The Views editor only allows assigning one look to a view, but multiple looks may be assigned by editing the OCIO config file directly.

Creating Views

If your OCIO config is missing a view, you may add one from within the application, as with other edits, this is stored as an override rather than modifying the source config.

There are two two main scenarios: creating a view from components that already exist within the config; or creating a view transform using your own LUT and then using that to create a view.

This section will describe how to create a view from components that already exist in the project's OCIO config. However, keep in mind that you may also create a view transform from one of your own LUTs and use that as the component for creating a new view. See: Adding a User LUT as a View Transform.

The best-practice in OCIO is to create a view from a view transform. A view transform is a transformation from the config's scene-referred reference space to its display-referred reference space. This transform generally includes an S-shape curve or tone-map that brings the very wide range of luminances in a scene into the more limited range that is available on a display. In addition, it applies other corrections such as accounting for human visual system adaptation and stray light in the capture and projection systems.

A view transform generally does not convert all the way to code values for a specific display, in order to allow it to be used with a range of similar displays. Examples of this are the view transforms that implement the ACES Output Transforms. Therefore a view transform always relies on being combined with a display colour space to get all the way to display code values for a specific device.

However, OCIO is very flexible and it is also possible to create a view from either a colour space or a named transform. This is less desirable because this approach does not use a separate display colour space, which generally leads to a clunky workflow. However, there are situations where this is done, either to accommodate older ways of working with OCIO, or to implement special-purpose views (e.g., for diagnostic purposes).

Create a new view as follows:

1. Press the Create View button to create a new view. This is the text that will appear in the lower-left corner of the viewports.
2. Press in the View Transform field and select the view transform, colour space, or named transform to use.
3. Press in the Allowed Colour Space field and select the type of colour spaces this view should be used for (see the section above for more detail). The most common scenarios are generally "Any Scene-linear or Log" or "Any Video".
4. Press in the Allowed Displays field and select the type of display to use the viewing transform with (see the section above for more detail).
5. Press in the Looks field to add one of the looks from the config.
6. Type a name for your rule in the Rule Name field. This is the name you will see in viewport menus.
7. Use the Up and Down buttons to set the priority of this view relative to the other views.

If a rule specifies one of the "Any" options in the Allowed Colour Space field, then the view transform will be available for use with a family of tagged colour spaces. If the colour space that the given view transform expects as input does not match that of the given image, the system automatically inserts the necessary transform to convert between the actual and expected colour space. Likewise, if one of the "Any" options is specified in the Allowed Displays field, then if the colour space produced by the given view transform does not match the display hardware currently being drawn to, the system automatically inserts the necessary conversion transform.

Considerations when Editing Views

You may want to mute or delete some of the views in a config to reduce the options and keep things simple. However, please keep in mind that the table must have at least one view that will work with every type of tagged colour space in the config. Otherwise, a viewport may not have a way to display certain types of images and you will see a black viewport with an error message in red text.