qt_add_lightprobe_images

Bakes HDRI map files to KTX files, adding them as Qt resouces.

The command is defined in the Quick3D component of the Qt6 package, which can be loaded like this:

find_package(Qt6 REQUIRED COMPONENTS Quick3D)

This command was introduced in Qt 6.2.

Synopsis

qt_add_lightprobe_images(target resource_name
                    [PREFIX prefix]
                    [BASE base]
                    FILES file1.hdr, file2.hdr ..
                    [OUTPUTS file1.ktx, file2.ktx ..]
)

If versionless commands are disabled, use qt6_add_lightprobe_images() instead. It supports the same set of arguments as this command.

Description

Use the command to bake .hdr files listed under FILES to .ktx files. The files will be included under in the binary or library target.

FILES should list paths to local HDRI map files. Each file must have either the suffix .hdr, or .exr. These files will be converted at build time to .ktx files, using the Balsam Asset Import Tool.

By default, the .ktx files will show up in embedded Qt resources of the target binary under the same base name and relative path. Use BASE to remove a common directory from the relative paths at runtime. That is, if all the file paths under FILES point to a common directory maps/, then you can use BASE maps/ to hide the directory in the Qt resource system. In a similar vein, you can use PREFIX to add a common prefix directory in the Qt resource system.

While BASE and PREFIX allow you to change the comon relative paths of the .ktx files in the Qt resource system, OUTPUTS allow you to control the full path of the .ktx files, including the file name. If you use OUTPUTS, the number of paths have to match the number of paths to FILES.

Example

The following autogenerates the lightprobe map at build time and includes it in the executable under :/maps/OpenfootageNET_garage-1024.ktx:

qt_add_lightprobe_images(principledmaterial "ibl_assets"
    PREFIX
         "/"
    FILES
        "maps/OpenfootageNET_garage-1024.hdr"
)

Caveats

When adding multiple resources, resource_name must be unique across all resources linked into the final target.

This especially affects static builds. There, the same resource name in different static libraries conflict in the consuming target.