Today was something of an anti-climax, blog-wise; after about three or four solid days' work invested in the Undo/Redo routine in the past, I managed to sit down and code a new, working routine in the space of an hour! After setting up the buffers and variables, it was merely a case of tackling each bit of functionality in a methodical fashion (I'm certain that looking at old notes or code would have confused me further, and possibly why successful results have eluded me in the past).
Flushed with this success - although extremely sceptical that the routine works at all - I added some extra variables to store the map number, as well as the cursor positions - this way, when the user steps back with Undo, they'll be returned to the relevant layer and screen position.
Turned my attention to the Text Display routine, which seems to flicker in different ways on different machines. Although some chunks of text have flags attached to them (so that the text is only updated if information changes), some didn't, so a small amount of time was devoted to tidying up the code and adding extra checks. The Editor looks exactly the same on my Win2K setup, bt I shall be testing this routine with interest on my laptop.
Next came a small toolbar tweak, with the addition of a Show All option positioned between the Zoom Out and Zoom In icons (something of an oversight, in retrospect).
