How to read a line
Thickness is salience — how much the claim explains, next to the alternatives. It is measured in screen pixels and does not shrink with distance, so a thick line at the back is still a thick line.
Opacity is how true it is. These are two different claims and the corpus never collapses them into one number.
Colour is the kind of claim. A steel line runs scene to scene. A violet line is an influence reaching a scene it touched — the colour its own square is drawn in. Colour says which kind, never how strong or how true: those are the thickness and the opacity.
Depth is focus, not fade. A line further away goes soft at the edge and loses a little colour to the ground. It keeps its width and its opacity, because both of those already mean something else.
Dotted and faint is a negative touch: something the corpus says did not reach a scene. It is an absence, not a connection.
Long-dashed means a number is missing rather than low — nobody has scored that link.
Short-dashed is an influence sitting inside its home scene rather than reaching out to one. It carries no salience or truth because it is not that kind of claim.
Round is a scene, square is an influence, hollow is a stub that has been seeded and not yet written. A point's size is how many claims touch it.