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METAVIEW.ACC, METAVIEW.PRG, and the associated documentation are (C)opyright 1988, 1989 by Ric Clayton. MetaView is an un-registered trademark of SoftWave Studios. All versions of MetaView (hereinafter referred to as "the software") are copyrighted by the author. The author reserves all rights with respect to the copyright, including, but not limited to, ownership, sale, and distribution of any and all versions of the software. No version of the software may be sold or included in a commercial package without written permission from the author. The current version of the software is being distributed as "Shareware". It is not free. You may upload it to information services and networks (like GEnie, CompuServe, USEnet, etc.) or give it to friends for evaluation. You may use the software for a limited time to evaluate it. If you like it and wish to continue using it, you should become a registered user. You become a registered user by sending $25.00 (US) to the author. (Be sure to include a note that you are registering as a user of the software.) Registered users will receive notices when new versions are available. Registered users may also obtain the latest version of the software, when available, by sending a 3.5" Floppy Disk and $5.00 (US) to the author. (The more registrations I receive, the more motivated I will be to enhance and maintain this software and produce more Shareware.) MetaView was designed and programmed by Ric Clayton using the Megamax Laser-C development system. Inquiries, comments, suggestions, registrations, donations, etc. are welcome and should be addressed to: Ric Clayton 1000 Escalon Ave. #1126 Sunnyvale, CA. 94086 USA GEnie: RIC Portal: Ric Clayton USEnet: ric.i.clayton@portal.com CompuServe:[73317,1350] 1.0 What it is MetaView is a program which allows you to view GEM Metafiles in standard GEM windows. (Metafiles are files with a .GEM extension, such as those produced by EasyDraw and GEM-Draw.) Two versions are included on the distribution disk; a GEM Desk Accessory (METAVIEW.ACC) and a GEM Application (METAVIEW.PRG). Both function identically. The Accessory version will function from within other GEM applications that allow you to access Desk Accessories. MetaView will display any GEM Metafile, in any resolution, with or without GDOS installed, and (hopefully) run on any version of TOS. MetaView contains a robust window manager. You'll find you can do things to MetaView's windows that most other applications don't support. I've tried to make MetaView's functions easy to operate and remember. If things are confusing at first, don't be afraid to experiment. With a little practice, working with MetaView will become natural and obvious. 2.0 The Menu Selections The menus for both the program and accessory versions are virtually identical. The exception is that the accessory version has no "Quit" selection, since GEM Desk Accessories cannot terminate. In addition, the accessory version displays all it's selections in a single menu which pops out of the "MetaView..." Desk Accessory menu selection. 2.1 "About Metaview..." This displays a box containing version and copyright information. The number of windows MetaView currently has open is displayed at the bottom of the box. Click anywhere on the screen to remove the "About" box. 2.2 File - "View Metafile..." Opens a window and reads a metafile for viewing. The metafile is selected with the standard GEM file selector. (The same thing can be accomplished with the Window "Open" function, but this is much quicker.) 2.3 File - "Quit" Available in the program version only, terminates MetaView returning you to the application that invoked it (usually the GEM Desktop). 2.4 Window - "Open" This allows you to selectively open a MetaView window. When you left-click on "Open", a window sub-menu will pop out with a title of "Open Window". From this menu you may select a specific MetaView window. If the window selection contains a file name, indicating the window had been previously opened, left-clicking the selection will re- open the window to its previous position and size to view the indicated metafile. If the window selection is empty, left-clicking the selection will bring up the file selector so you may select the metafile to view. Holding down the Right mouse button whilst left-clicking a previously opened window selection will also bring up the file selector. This allows you to change the metafile to be viewed without altering the window's prior position and size. The "All Windows" selection at the bottom of the sub-menu allows you to reopen all previously opened windows in a single operation. This is especially handy when you had windows open on the Desktop and want to view the same windows after entering an application. You can quickly re-open the last window you closed by holding down the Right mouse button whilst selecting the Window "Open" function. This bypasses the sub-menu and reopens the last window you closed. If there are no previously opened windows available but more windows can be opened, MetaView will ask you to specify a metafile by bringing up the file selector and open a new window. (This the same as selecting "Open Metafile..." from the File Menu.) 2.5 Window - "Close" This allows you to selectively close a MetaView window. When you left-click on "Close", a window sub-menu will pop out with a title of "Close Window". From this menu you may select a specific MetaView window to close. The "All Windows" selection at the bottom of the sub-menu allows you to close all open windows in a single operation. You can quickly close the top window by holding down the Right mouse button whilst selecting the Window "Close" function. This has the same effect as clicking on the "close box" in the upper right corner of the top window. 2.6 Window - "Top" This allows you to selectively make a MetaView window the "Top" window. When you left-click on "Top", a window sub-menu will pop out with a title of "Top Window". From this menu you may request a specific MetaView window be placed on top of all other windows on the desktop. Note that MetaView's "top" window is not necessarily the "top" window on the desktop. You can place MetaView's top window on top of all other windows by holding down the Right mouse button and left- clicking the Window "Top" function. This has the same effect as clicking on the window's title line. This function is most useful when you want "Top" a window which is totally covered by other windows. 2.7 Window - "Frame" This function allows you to move and size a MetaView window in a single operation. When you select the "Frame" operation the mouse cursor turns into a shape resembling the upper left-hand corner of a square. Move the mouse so that the cursor is where you want the upper-left corner of the window to be. When you have the upper left corner position established, hold down the Left mouse button. The mouse cursor will change to look like the lower right-hand corner of a square. While continuing to hold down the Left mouse button, drag the mouse towards the lower-right of the desktop. You'll see an expanding rubber box showing the size the window will be at its new position. When you're satisfied with the size of the box, release the Left mouse button and the selected window will move and resize itself. As with other Window operations, Left-clicking the "Frame" selection brings up a window sub-menu and holding the Right mouse button down while left-clicking "Frame"s MetaView's top window. The "All Windows" selection in the sub-menu will enable you to frame each open window one at a time. The window waiting to be framed will change it's title to the window number surrounded by two outward point arrows, like "<< 1 >>". Framing operation begins with the top window and continues with each window in order. If you initiate a Frame operation and then decide you don't want to do it, you may cancel the Frame. While MetaView is waiting for you to specify the upper right-hand corner of the window, left-click once instead of dragging out the rubber box and the Frame will be cancelled. 2.8 Window - "Full" This is equivalent to clicking on a window's "full" box. (The one in the upper-left corner of most windows.) If the window is not already full, then it is made full. If the window is already full, then it is returned to its prior un-full size and position. Left-clicking the Window "Full" selection will bring up the standard MetaView window sub-menu. Holding down the Right mouse button and left-clicking "Full" will full MetaView's top window. Selecting "All Windows" from the sub-menu will apply a "full" operation to each open window, fulling those that are un-fulled and un- fulling those that are fulled. 2.9 Window - "Redraw" This operation requests that MetaView completely redraw one or more of it's open windows. This is handy when you've been moving several windows around with redrawing inhibited (left-shift and alternate keys held down). Left-clicking on the "Redraw" selection will bring up the standard Metaview window sub-menu. Holding the Right mouse button down whilst left-clicking "Redraw" will cause MetaView's top window to be redrawn. Selecting "All Windows" from the sub-menu will instruct MetaView to redraw all of it's open windows. 2.10 Window - "Reset" Selecting this function will close any open windows, freeing any memory allocated to them, and reset MetaView's internal window table to it's initial state. This effectively erases MetaView's window memory. All window sizes and positions are reset, all filenames are cleared and the window order is reset to it's initial sequence of "1,2,3,4,5,6,7". The only thing MetaView retains is the last path used in the file selector. 2.11 Font - "Load" and "Unload" These selections are used to instruct MetaView to load and use any available GDOS fonts or use the built-in system fonts. If GDOS is not active, or not installed, then both selections will be disabled and only the system fonts will be used. If GDOS is installed and active, the "Load" selection is enabled and the "Unload" selection is disabled. This indicates that the system fonts will be used to draw text, which is what MetaView defaults to. Selecting "Load" will instruct MetaView to use GDOS fonts in subsequent drawing operations involving text. If the fonts have not already been loaded by another application, selecting "Load" will also cause GDOS to load all assigned screen fonts into memory. Notice that the "Load" selection is now disabled and the "Unload" selection is enabled. This indicates that GDOS fonts are loaded and will be used by MetaView. Selecting "Unload" instructs MetaView to stop using GDOS fonts and return to using the system fonts only. If MetaView is the only application using GDOS fonts when "Unload" is selected, then GDOS will also remove the fonts from memory. The Font selections will now be back to their initial state, "Load" is enabled and "Unload" is disabled. 3.0 Behind the Scenes 3.1 Window Memory MetaView remembers the last position and size of an open window, as well as the metafile that was being viewed in the window. It also remembers the order in which the windows were last placed on the desktop. This order is reflected in the ordering of selections in MetaView's window sub-menus. 3.2 File buffering When a Metafile is opened, a buffer for the file is allocated in the computer's memory and the entire file is read into memory. All drawing will thereafter be done from this buffer. If then there is not enough memory to allocate a buffer for a metafile, an alert will be displayed. You'll have to close one or more windows or exit the application to make room for the file buffer. (Future versions will provide an option to draw directly from disk when there is no memory available for a buffer.) 3.3 Window Sub-Menus Window sub-menus give you access to MetaView's internal window table. Using the sub-menus you can apply any Window menu operation to any MetaView window. There is no requirement to bring a MetaView window to the top of the desktop in order to manipulate it. If you Left-click one of the Window menu operations, a sub-menu of window selections will be displayed. Left-clicking on a specific window selection will apply the operation (Open, Close, etc.) to the selected window. With the exception of "Open", all window sub-menus allow you to apply the Window operation to any open window. ("Open" only works on un-open windows.) With the exception of "Top", any operation may be applied to all windows. (Since only one window can be the "top" window in GEM, topping all windows makes no sense.) Left-clicking on the Window selections (Close, Top, etc.) whilst holding down the Right mouse button, with the exception of "Open", applies the operation to MetaView's Top window. (Note: this may not be the visibly Top window if another application is displaying a window on top of MetaView's windows.) The Window Open function, in this case, re-opens the last window that was open, or the next available window if there was no previously opened window. 3.4 Window Ordering MetaView remembers the order in which windows appear on the desktop. This is reflected by the ordering of selections in the window sub-menus. MetaView's top-most window will be the first selection in the sub-menu, followed by the window under the top window, and so on. A check mark appears next to the first selection in the window sub- menus to remind you that this is MetaView's top window. 3.5 Window Titling Window titles consists of the window's internal number and the name of the metafile being displayed. During some operations, a windows title will change to indicate the operation being performed. When a metafile is being loaded from disk, the window title will change to the window's number surrounded by two inward pointing arrows. For example; when a file is being loaded for display in window #1, the window's title will look like: >> 1 << When a window is being "Framed", it's title will change to the window's number surrounded by two outward pointing arrows. For example; whilst Framing window #2, the window's title will look like: << 2 >> While a window is being drawn, its title will change to the window's number surrounded by two little clock faces. 3.6 Window Redrawing MetaView does not actually do any drawing. It just translates metafile information into a form acceptable to GEM's Virtual Device Interface (VDI). Its the GEM VDI that does the actual drawing of metafile objects. MetaView also does not analyze any of the metafile information. Because of this, window redrawing may take quit a while to complete. This is mostly evident when several complex metafiles are being viewed with un-even overlapping windows. Due to this, MetaView provides a way for you to keep it from redrawing windows. Window redrawing may be stopped by holding down the left-shift and alternate keys at the same time. Holding the keys down momentarily will stop redrawing the current window being drawn. Holding the keys down for a longer period of time will stop the redrawing of several or all windows, depending on how long the keys are held. Continuously holding the keys down will inhibit MetaView from redrawing any of it's windows. This can be useful when you want to quickly size and position several windows. 3.7 Fonts & GDOS MetaView will work with or without GDOS (or equivalent software) installed. Without GDOS, any text contained in the metafile will be drawn using the built-in system fonts. With GDOS installed, you may instruct MetaView to draw text using the loaded GDOS fonts. If the font defined in the metafile is not currently loaded, then the system font will be used by default. Note that since MetaView does not allow metafiles to be changed, saved, or printed, the only thing GDOS does for MetaView is allow it to use the additional fonts. 3.8 Fonts & the GEM Virtual Workstations GEM applications interface to devices, such as the screen or printer, through GEM Virtual Workstations. Several Virtual Workstations may be opened to a single device. The use of Fonts is dictated by each Virtual Workstation, independently of all other Virtual Workstations opened to the device. Only the first Virtual Workstation requesting GDOS to "load fonts" will actually cause GDOS to read the fonts from disk into the computer's memory. Additional requests to "load fonts" from other Virtual Workstations opened to the same device will not cause the fonts to be read from disk again. Thus, Virtual Workstations all share a single copy of the fonts in memory. Only the last Virtual Workstation to request GDOS to "unload fonts" will actually cause the fonts to be release from memory. Since MetaView is a GEM application, it opens it's own Virtual Workstation to the screen. It thus has independent control over the use of GDOS Fonts. When MetaView is running as a Desk Accessory, even though another application (like EasyDraw) has loaded fonts, MetaView will still have to be instructed to use them. 4.0 The Bad Stuff 4.1 Limitations The current version of MetaView does not support GEM Image (.IMG) files. I don't know what it will do if you try to view a metafile which references a .IMG file. It may be harmless, it may crash your computer. (GEM-Paint is one application I know of that generates such metafiles.) If the a metafile can't fit into available memory, it can't be viewed. A future version of MetaView will include an option to allow metafiles to be drawn directly from disk rather than from memory. The MetaView Desk Accessory closely follows the rules for processing accessory close messages from GEM. It releases all memory it has dynamically allocated and closes its of the Virtual Workstations it has opened. This enables MetaView to co-operate with the GEM Desktop and other GEM applications very well. However, current versions of TOS do not send an accessory close message to Desk Accessories when the screen resolution is changed. This means if you change screen resolutions while there are MetaView windows open the memory allocated to the open windows will be lost and unusable until you re-boot your computer. Doing this repeatedly will eventually use up all memory resulting in a crashed computer. Remember, always make sure all MetaView windows are closed before changing screen resolutions. 4.2 Known Bugs These little rascals are always lurking in the wood work. The only bug I know of in this version is that sometimes the positioning of some text will be all screwy. I'm not sure what causes this, but it doesn't seem to do any harm other than spattering characters randomly in the window. This phenomena is exhibited by both the program and accessory versions of MetaView. As you might suspect, a system re-boot is the only way I know of to cure this problem. This doesn't mean there aren't any other bugs. I've made every effort to make MetaView bullet-proof. However, there is always the possibility I missed something; there may be situations I am unaware of and therefore did not account for. If you find any bugs, I would surely like to know about them. Please drop me a line describing the symptoms and, if the problem is reproducible, how you made it happen.