Urban Design Metaphor

Extracted from VirtualDesktopsDiscussion:

By landmarking I mean the deliberate creation of landmarks by the system for their usage as landmarks by users. Landmarks are one of the 5 concepts of spatial navigation, alongside nodes, paths, districts and edges (of districts). -- RK

Sorry, I'm not well versed in CHI/GUI terminology, Your explanation of landmarks by landmarks (same word 4 times) didn't help. I will look it up some time.

Sorry, that's terminology from urban design. Okay,

A landmark is a reasonably unique object used as a point of reference for navigation. To function as such, landmarks are very big and can be seen from a distance.

A node is a place that a person can mentally enter. For example, a public square or a mall.

A district is a contiguous collection of nodes and paths with their own distinctive character.

An edge is the boundary of a district.

We seem to define mouse operations and keyboard operations much the same way except for a middle area which I'm not sure how to characterize. What I'd like to know is all the places you use a keyboard where I use a mouse, to be able to figure out why this is so. Short term symbolic memory is one factor explaining the difference but since I don't know the whole difference I can't tell if it's the only factor. Knowing this seems important. -- RK

Okay, I knew the common meanings of the words, but had not such a clear definition for them in mind. But I still have problems to transfer these metaphors to the desktop. I'll try:

A district may be an 'application', i.e. a coherent group of interacting components with a common 'culture' of how to use it.

A node is then an interface component like a windows, which you can 'open' or click to the front (=mentally enter?).

Paths are the drag'n'drop paths or navigation paths (like Menu->File->Open->...).

A landmark is then either a large image or a menu-bar with a unique text/color/pattern.

What the edge I cannot fathom. But am I close with the other points? -- .gz

Most applications don't serve as districts because they don't group large numbers of similar objects together. Take for example MS Word or Gimp and contrast the number of objects they group (1 or 2) with eMule (>500). And actually for eMule to be a district, the objects it groups together would have to be nodes, which they are not because you can't inspect them in any meaningful way. Smalltalk counts as a district but then Smalltalk is an OS. The only obvious examples of applications as districts I can think of are CrudScreen applications.

In my OS design, OS components are domains. So the hard disk driver is a domain composed of all the disk blocks within its purview.

You are correct that windows are nodes. In my design, nodes are nodes. :)

There are no paths in modern GUIs. A path isn't merely a notional series of steps but is a continuous, persistent, independent object in some space. The closest thing to paths in modern OSes is directory paths in CLIs and they are discrete, subjective and transitory, which is why people don't really use them as paths.

Also, paths links nodes and a menu isn't a node because it's too small. A menu is the analogue to a boutique beside a path; too small to be a place on the scale we're concerned with. You can change scale so that menus are paths but then you have to stick to the scale you've chosen. On the scale at which menus are nodes, individual windows may be entire districts.

I plan to have real paths which you can see and retrace. Going along a different path won't erase the path you've taken. And if you so choose, your paths will be visible to others.

Again, wrong scale for landmarks. Some of the more common landmarks in Windows are My Computer, C:, Desktop, Start, and My Documents. Unix doesn't really have landmarks unless you're a sysadmin and even then it still doesn't really have landmarks; /etc and /dev are landmarks but /bin, /sbin and /usr are too convoluted. And in Unix, any landmarks that exist aren't presented any differently from non-landmarks.

If an application is a district then the edge is the border of the window it's in.

If we take this wiki as our example, then RecentChanges is the most prominent landmark, each page is a node, there aren't really paths, each SisterSite is its own district, and the logo at the bottom of a TwinPage is an edge. -- RK

Ah, I see, its a metaphor you use (or want to use), but I didn't get it earlier or you didn't make it clear enough, that it plays an important role for you. Do you want to elaborate on it here? -- .gz

Nothing much to elaborate. It comes from urban design but it's not a metaphor because it's not tied to urban design. Consider that it's not inherently two dimensional, but cities are. So it's just a good language for spatial navigation. Other useful terms include locomotion and wayfinding which together make up navigation.

I got it all from Navigation in Electronic Worlds: Research Review by Modjeska (http://www.dgp.utoronto.ca/people/modjeska/Pubs/lit_rvw.pdf) which I really should finish reading one of these days. -- RK

CategoryMetaphor