Adding (buried) features from Yocto layers that are present in your build - yocto

Question

I'm a neophyte with Yocto, though I have been able to glean enough from tutorials to create an image that meets some of the requirements for my current project. I'm able to create my own layer and recipe so I can generate it with bitbake, e.g. bitbake mycustomimage.
I'm working with a beaglebone and the tutorials I've followed state you need the following layers:
meta-arm
meta-ti
poky (of course)
Just following the beagelbone tutorials will allow you to create a variety of prepackaged images from default recipes. However, tutorials and Yocto documentation do not explain how to access features and applications contained in the existing layers but are not utilized by the default recipes. I'm aware that you can use the IMAGE_FEATURE and EXTRA_IMAGE_FEATURE variables to add some (prepackaged) support.
I've come up with a way to add features from other layers by copying them into my custom layer directory structure and adding them to my customimage.bb file. This technique feels hacky and potentially error prone, also it duplicates files and directories found in other layers. My question is:
How are you supposed to add features from existing layers added to your project? For example I'll be needing PRU support for my beaglebone project, I know where those features are in the meta-ti layer (found in the recipes-bsp/ directory). How can I access that support and those features without a stupid hack? There must be a way.
Here's an example. I needed xorg-minimal-fonts installed, the recipe is contained in the poky/meta/recipes-graphics directory. I copied the contents into my custom layer which looks something like this:
mycustomimage
├── conf
│   └── layer.conf
└── recipes-core
├── images
│   └── core-image-mycustomimage.bb
└── xorg-font
├── encodings
│   └── nocompiler.patch
├── encodings_1.0.5.bb
├── font-alias-1.0.3
│   └── nocompiler.patch
├── font-alias_1.0.3.bb
├── font-util_1.3.2.bb
├── xorg-font-common.inc
├── xorg-minimal-fonts
│   └── misc
│   ├── 6x13B-ISO8859-10.pcf.gz
...(a bunch of zipped fonts)
│   ├── cursor.pcf.gz
│   └── fonts.dir
└── xorg-minimal-fonts.bb
My custom layer .bb file looks like this:
IMAGE_FEATURES_append = " x11-base ssh-server-dropbear hwcodecs"
IMAGE_FEATURES_remove = "allow-empty-password"
IMAGE_FEATURES_remove = "empty-root-password"
require recipes-core/xorg-font/xorg-minimal-fonts.bb
IMAGE_INSTALL = "\
packagegroup-core-boot \
packagegroup-core-full-cmdline \
${CORE_IMAGE_EXTRA_INSTALL} \
xorg-minimal-fonts \
"
inherit core-image extrausers
I know this is not how you're supposed do this, but it did work.

Answer 1

If you have a custom layer with a custom image, you can add any recipe that is in other layer.
If you copied xorg-font folder for that reason, it means that you need to copy all folders also of what you set in IMAGE_INSTALL.
You do not need to require the xorg-minimal-fonts recipe in the image recipe.
Also, IMAGE_INSTALL = .. will override the IMAGE_INSTALL of core-image class, so here is your custom image after some fixes:
# Inherit core-image because it already has:
#
# CORE_IMAGE_BASE_INSTALL = '\
# packagegroup-core-boot \
# packagegroup-base-extended \
# \
# ${CORE_IMAGE_EXTRA_INSTALL} \
# '
# ...
# IMAGE_INSTALL ?= "${CORE_IMAGE_BASE_INSTALL}"
inherit core-image extrausers
# Activate features
#
# Activate x11-base only if x11 is in DISTRO_FEATURES
IMAGE_FEATURES_append = " ${#bb.utils.contains('DISTRO_FEATURES', 'x11', 'x11-base', '', d)}"
IMAGE_FEATURES_append = " ssh-server-dropbear hwcodecs"
IMAGE_FEATURES_remove = "allow-empty-password"
IMAGE_FEATURES_remove = "empty-root-password"
# Add custom recipes
IMAGE_INSTALL_append = " xorg-minimal-fonts"