README
1Warsaw, 1998.08.18
2
3 VIEW - small PNG viewer
4 -----------------------
5
6This program is intended to serve as a simple console viewer for PNG
7graphics. It also features some scripting abilities, which allow you to
8build simple presentation.
9
10In fact, using even this initial version I was able to build a nice
11presentation of PicoBSD abilities which I used in real-life situation (you
12can see for yourself one of the presentation's screens, fbsd.png).
13
14The audience was impressed :-), especially when I asked them politely what
15are requirements and cost to make that kind of presentation using M$
16products...
17
18Simple Viewing
19--------------
20
21Usage is as follows:
22
23 view [-g nnn.nnn] [-r x] filename.png
24
25where
26 -g nnn.nnn screen gamma (you can adjust how bright is the
27 picture)
28 -r x resolution:
29 0 - 640x480x16
30 1 - 640x200x256
31 2 - 320x240x256
32
33Under right mouse button you can find a simple menu, which tells you also
34the hotkeys. You can shift, rotate and zoom the picture.
35
36Presentation
37------------
38
39Usage is as above, but the file you give as argument is a (unix) text file
40of the following format:
41
42 1 VIEW SCRIPT
43 2 5
44 3 welcome.png
45 4 /home/clipart/logo.png
46 5 /home/present/title.png
47 6 /home/present/outline.png
48 7 /home/present/end.png
49
50(of course without the line numbering or the leading space!). The line number
511 is magic, and must be present in order to recognize the file properly.
52
53The second line tells how many pictures consist the presentation. The
54following lines tell the file names containing the images themselves.
55
56See the example in file picobsd.vu.
57
58Command line arguments (gamma and resolution) are as above. You can also use
59the pop-up menu to adjust image parameters, as well as go forward or
60backward in the presentation.
61
62Bugs, caveats, missing features
63-------------------------------
64
65* there are some bugs in libvgl which require strange workarounds, and even
66 then it doesn't work quite right. See the source for the 'XXX' comments...
67
68* I didn't have time to add gamma adjustment to the pop-up menu. It's
69 simple, though, and I leave it as an exercise for the reader :-))
70
71* it would be great if someone would add GIF and jpeg support.
72
73* the error checking is probably weak. A bad PNG file or script file will
74 probably cause a coredump.
75
76* pop-up menu facilities need more abstraction to be usable in other cases.
77
78Anyway, as it is even now it's quite usable.
79
80Have fun!
81
82Andrzej Bialecki
83
84<abial@freebsd.org>
85
86$FreeBSD$
87
