Deps: add comments noting why packages are installed

Some don't seem to be needed anymore, noted these in comments too.

1 files changed, 29 insertions, 1 deletions

diff --git a/build_files/build_environment/linux/linux-centos7-setup.sh b/build_files/build_environment/linux/linux-centos7-setup.sh
index 6cef1d718c7..f07db91cc38 100644
--- a/build_files/build_environment/linux/linux-centos7-setup.sh
+++ b/build_files/build_environment/linux/linux-centos7-setup.sh
@@ -28,40 +28,68 @@ yum -y install devtoolset-9
 # Install packages needed for Blender's dependencies.
 
 PACKAGES=(
+    # Used to checkout Blender's code.
     git
+    # Used to checkout Blender's `../lib/` directory.
     subversion
+    # Used to extract packages.
     bzip2
+    # Used to extract packages.
     tar
+    # Blender and some dependencies use `cmake`.
     cmake3
+    # Apply patches from Blender's: `./build_files/build_environment/patches`
     patch
+    # Use by `cmake` and `autoconf`.
     make
+
+    # Required by: `external_nasm` which uses an `autoconf` build-system.
     autoconf
     automake
     libtool
+
+    # Meta-build system used by various packages.
     meson
+    # Builds generated by meson use Ninja for the actual build.
     ninja-build
 
+    # Required by Blender build option: `WITH_GHOST_X11`.
     libXrandr-devel
     libXinerama-devel
     libXcursor-devel
     libXi-devel
-    libX11-devel libXt-devel
+    libX11-devel
+    libXt-devel
 
+    # Required by Blender build option: `WITH_GHOST_WAYLAND`.
     mesa-libEGL-devel
+    # Required by: Blender & `external_opensubdiv` (probably others).
     mesa-libGL-devel
     mesa-libGLU-devel
 
+    # Required by: `external_ispc`.
     zlib-devel
+    # TODO: dependencies build without this, consider removal.
     rubygem-asciidoctor
+    # TODO: dependencies build without this, consider removal.
     wget
+    # Required by: `external_sqlite` as a build-time dependency (needed for the `tclsh` command).
     tcl
+    # Required by: `external_aom`.
+    # TODO: Blender is already building `external_nasm` which is listed as an alternative to `yasm`.
+    # Why are both needed?
     yasm
 
+    # Required by: `meson` (Python based build system).
     python36
+    # Required by: `mako` (Python module used for building `external_mesa`)
     python-setuptools
 
+    # Required by: `external_igc` & `external_osl` as a build-time dependency.
     bison
+    # Required by: `external_osl` as a build-time dependency.
     flex
+    # TODO: dependencies build without this, consider removal.
     ncurses-devel
 
     wayland-devel