Fallout 4 Perk Icons
The perks screen uses fading to indicate a skill you don't have, and outlining to indicate a skill you can't have (due to not meeting the requirements), see this screenshot here:If you've got skills that are faded out, you should be able to get these by clicking on them and then pressing the confirmation key as prompted at the bottom of the screen:If the perk is outlined entirely, hovering over the perk will still tell you what it does but also inform you of why it's outlined (not enough strength in my case). There's one exception to these general rules: if you already have one or more levels of a skill, that icon looks the same whether or not you meet the requirements for the next level of that skill (these are usually character level requirements). Once you have at least one level in a skill there's no way to differentiate from the icon whether you can or can't upgrade it.
Fallout 4 Perk Icons Download
Fallout 4 Perk Icons Download
So unfortunately you need to hover over every one of these skills to see whether you can upgrade it. Unless I'm missing something-which surely I hope I am.–Nov 14 '15 at 15:10.