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- Manual|Sat,30 Mar,1993|MkChar
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- MkChar|Sat,30 Mar,1993|Manual
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- |JGEd
-
- The application !JGMakeCh is provided to enable editing to take place in JGEd
- with Top\-Bit and VDU characters redesigned to correspond to those of some
- Printer set e.g. PC-8. From within JGEd, the extended command Character
- Pixel/<file>/ has now been implemented, as have the arrangements for the vdu
- characters, but you may also use the arrangements described in the next three
- paragraphs.
-
- Outside JGEd, for files of top-bit set characters only, the definitions in the
- character design file <mkchar$dir>.JGChars can be put into effect and cancelled
- by the two obey files JGSetChar and ArcChars; this is best seen in the !chars
- window.
-
- It is vital that, used in this latter way, this design file does not contain
- definitions for vdu characters, otherwise unexpected effects may well occur.
-
- JGSetChars contains the single line "copy <mkchar$dir>.JGChars rawvdu: ~C ~V",
- and you can change the filename, <mk......ars, to put any other file into
- effect.
-
- Technical note: Character definition files contain an ordered list of character
- definitions, where a character definition is 23 <chrano> <64bytes>, where
- <64bytes> are in the order required by vdu 23 <charno> <n1> <n2>, or OSWord 10.
- To look at them in the raw, use To Dump in JGPCopy.
-
- !JGMakeCh has been designed to develop a file of character definitions,
- held in an internal vector, CharV, indexed from 0 to 255. The vector can be
- filled by dragging a character definition file to the JGMakeChar main window,
- and the file icon near the bottom of the window will hold the last file name
- loaded.
-
- To save CharV, click on the Save button, and a save window will come up. If you
- click with Select, what was previously in the file icon of this window
- (originally JGChars) will be preserved; if you click with Adjust, the loaded
- filename will be transferred to the Save window. Dragging in a file of partially
- developed characters and saving with Adjust enables the development process to
- be spread over more than one session.
-
- The main window contains an 8x8 pixel area where each pixel can be turned on and
- off by clicking on it. To the right is a number, expressible either as a decimal
- or as a hexadecimal (preceeded by &). This is the byte number in terms of which
- this character design can be saved in CharV or effected as a current Ch, or
- both. There is a Done light that flashes on and off to confirm that these
- actions have been executed.
-
- The pixels can be filled from CharV, or from the current Chs. In either case,
- the number of the byte to be taken is set in the window opposite the
- command ("Get from CharV" or "Get Ch") and the user clicks on the command, not
- on the window.
-
- Since there is frequent content overlap in different character sets, it is often
- possible to make a character for the new set simply by getting the character
- which realises a different byte in current Chs, or from a file inserted into
- CharV; where this is not possible, another character often serves as a starting
- point to save some of the labour of character design.
-
- If you take from 32(space) of the current Chs, the pixel area will normally be
- cleared.
-
- The icon 'Exclude vdu characters' swaps to and from 'Include vdu characters'
- when clicked, and governs how much of the CharV designs are saved. Obviously, if
- you are intending to use JGSetChars, you must not have included the vdu
- characters in your character design file. Files including the vdu characters are
- intended only for the cp facilities of JGEd. When designing for such a file, it
- is wise to switch to 'Include...' at the beginning of the session.
-
- Finally, there is a quit icon to quit with at the end of a character designing
- session. I may include a warning to save CharV.
-
-
-