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#### 9.3.1 Lost Messages

Sometimes one want to express that a message is lost. You can do this in Msc-generator in two ways. Either, you can add an asterisk between the two entities where the message is lost; or you can add a ’lost at’ clause after the arrow specification before the label or attributes. This causes a small `x` to be drawn at the place specified and the dimming of the remainder of the arrow.

The first three ones are the quick one. The message lost will be indicated around the entity after or before the asterisk. Specifically, it will be between this and its neighbouring visible entity. If that visible entity is also part of the arrow, the loss will be at one third the distance between them, else it will be halfway. Using the second form, you can specify exactly where the loss happened. It can be placed onto an entity, left or right from it, or between two entities. These are specified as ‘`lost at <entity>`’, ‘`lost at <entity>-`’, ‘`lost at <entity>+`’ or ‘`lost at <entity1>-<entity2>`’, respectively. You can add two plus or minus symbols to increase distance. You can also specify any offset in addition by adding a number after, such as in ‘`lost at <entity> <number>`’. The number will be interpreted in pixels and shifts the vertical left or right depending on its sign.

The appearance of the loss symbol (the `x`) can be influenced using the `x.line.width`, `x.line.color` and the `x.size` attributes. The latter takes the same values as arrowhead sizes: `tiny`, `small`, `normal`, `big` or `huge`, with `small` as default.

The appearance of the lost portion of the message can also be influenced via the `lost.text.*`, `lost.line.*` and the `lost.arrow.*` attributes. Anything specified here will be added to the text, line and arrowhead format of the arrow. Currently only the color of the line and the arrowhead is overlaid with `++white,128` (for plain designs), making them weaker, but you can change to dash lines, specifly a narrower line or empty arrowheads.

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