enblend 3.2 can read and write openexr files when compiled with '--enable-openexr'. At the moment the dependency is automagically picked up only if openexr was previously installed. The ebuild should use the global 'openexr' use flag.
Created attachment 201560 [details, diff] enblend-3.2-openexr+eapi2.patch This patch uses EAPI=2 - it removes the "built_with_use" check and replaces it by a EAPI=2 USE dependency - it fixes the openexr automagic dependency
this is fixed in media-gfx/enblend-4.0_rc2, but it'll be masked until final 4.0 release. (I'm leaving the bug open untill it's unmasked)
I totally forgot about this, final 4.0 version has been in the tree for a while. closing.