
Andy Little wrote:
"Matt S Trentini" <matt_trentini@yahoo.com.au> wrote ...
Andy, your "unitless" concepts are terrific, keep 'em coming. :)
Thanks for the encouragement :-)
Back in the 'good old days', before GUIs and multitasking os'es, drawing on the display was a simple process, with some form of move_to, line_to, fill etc primitives. I guess I am trying to simulate that approach as closely as possible. IOW C++ currently has standards for character stream output, so I'm thinking... why not a standard for graphics stream output also?
I am not looking into embedding any intelligent objects in the 'canvas' to begin with, however I am trying to keep that in mind. The component approach of ATL/WTL is very interesting from that point of view, wherein you add your messaging by multiple derivation, combined with CRTP. This Might be a very useful mechanism to make dumb drawing objects intelligent. For example, if I had a dumb line, it should be possible to 'attach' a class that can detect if that line is being grabbed with the mouse and so on.
If I'm not mistaken, in this case, you would need the class to use the same metrics as the line. As you later say - you seem to only want millimeters. I don't think having only one set of metrics is a good thing. At least for me there are a lot of times when I need pixels. Best, John -- John Torjo -- john@torjo.com Contributing editor, C/C++ Users Journal -- "Win32 GUI Generics" -- generics & GUI do mix, after all -- http://www.torjo.com/win32gui/ -- v1.4 - save_dlg - true binding of your data to UI controls! + easily add validation rules (win32gui/examples/smart_dlg)