Conference hydra::amiga_v1

    I've been using Draw Plus for a while, mostly floor-plan type stuff.
    I do use UniGraphics ][ about 8 hours a day, so I consider myself
    pretty knowledgeable about a professional grade system.
    
    One of the more dangerous features of UG ][ is the ability to group
    entities across layers.  This is considered poor practice, since
    a large part may be rendered partially invisible by deactivating
    component layers.  The user then has no choice but to enable all
    256 layers to find the rest of his grouped part.  The danger comes
    into play with large files (I have some files with over 10,000
    entities), where the graphics memory will run out, causing a crash.
    (Oddly enough, my $40,000 MegaTEK terminal here at DEC only has
    187K of video memory).
    
    So, Aegis sidestepped the problem by only allowing a group to exist
    on a common layer.  For PC layout work, this may be a pain, but
    for mechanical assemblies, it's a safety feature.
    
    By the way, I consider Aegis Draw, AutoCAD and their ilk to be mere
    toys compared to UniGraphics.  The executable to UG ][ is 13 MBytes!
    This is a serious program, folks!  To be fair, I really haven't
    used Draw Plus extensively, but I find it to be severely limiting.
    I would be totally unable to do serious mechanical design work on
    it.                                                
    

With regard to the grouping of entities across layers:
	I disagree that it is poor practice allow this practice, indeed
I consider it an integral part of a multilayer automated drafting/design
package.  Since Drawplus is presented to the market as a multi-dimensional
tool capable of being applied to PC-board work, I further consider it an
element of the functional specification of the program.  One might infer
this from the fact that the data base structure of the program, which is
documented in the manual, allows these constructions, i.e., entity attributes
are preserved when the entities are linked in the data base to enable handling
them as a group.  I think the "flatness" of parts is an implementation error
in the graphics editor, not the entire program (the program consisting of
the data base structure design, editor, drivers, etc.).  Though I haven't
tried it yet, I imagine one might be able to manually restore the layer
information to parts in a drawing and display them as such, but once edited
they would revert to flat (no layer resolution) parts.  
	I consider PC board work without this feature not just a pain, but
impossible.  In order to illustrate my opinion in terms of my CAD experience
for PC board and other applications, here are a few instances where one
would employ the ability to use multi layered parts:
1. The layer attribute can be employed to resolve non-printing information
such as part attributes,: pin , finish, etc.  These may then be extracted
by a post processing program to produce parts lists, loading reports, net
lists, numerical control (NC) punch or drill tapes, etc.
2. Parts may have different shapes on different layers, yet must be maipulated
(moved, rotated) as a whole, such as the pc board IC symbol, which will
typically have a silk screen outline with some text, aone or two solder
mask patterns, component layer pads, solder layer pads, ground and power
plane clearences or thermals, and so on.  As it is now with Drawplus, these
must be maintained as seperate parts which must be stored and manipulated
seperately.  
3. Parts might have a layer with a shorthand representation that allows
editing and checking of ann entire drawing quickly; for example, a pc board
could have a layer with reps of all parts rendered without arcs or circles,
tremendously speeding up re-draws.

John

    

    Well, like I said in .1, maybe it is essential to group across layers
    in PC layout, but we never do it in the UG ][ world.  Just a matter
    of opinion, I guess...
    
    By the way, maybe you have an answer to this question... How does
    one remove parts from the 'parts in stock' list in a drawing?  I've
    read my documentation, but couldn't find a way to do this.

    Sorry for the delay on a response, but I can't find a reference
    in the docs for removing parts in stock.  A question I have is if
    this is a concept common among cad programs.  It seems to me that
    it is an internal detail that needn't be of concern to the user,
    and that producing parts list is properly handled as a post-processing
    task.  The way I see it is that one copies a part from a library,
    and the system maintains but a single copy in the drawing data base,
    like the macros concept in assemblers.
    
    Is there anyone else out there using/interested in Draws Plus?
    

    I've used it a little...but not very much.  The improved printer
    routines make it a little more useful to me.  I can't  afford a
    plotter.
    
    However, I haven't come up with many useful things to use it for
    yet...
    
    

    Re: .4
    
    The reason I queried about the removal of 'Parts in Stock' is that
    I believe that Draw Plus holds the parts in chip ram.  I have a
    floor plan of my new house done, and I have about two dozen various
    widgets in stock.  They are always instantly available from memory
    without any disk access.  This wastes my valuable chip ram.  I'd
    rather it store the parts list and related parts on disk.
    
    The analogy in UniGraphics is called 'Part Merge', where you are
    allowed to merge any file, regardless of directory location or size,
    into the current drawing.  The user has the option of carrying over
    view-dependent edits, or just the raw geometry.
                                                             
    None of this is intended as criticism of Draw Plus; I think it's
    a real forward step in getting serious applications running on the
    Amiga.  It's just that one of the Amiga's more serious limitations
    is chip ram.  Programmers should take every step to release chip
    ram back to the system whenever possible, even if it means a little
    disk access or swapping into fast ram.
    

    Is anyone using Aegis Draw to create floorplans. If so do what kind
    of problems are you having. I am working on a CAD program specifically
    designed for floor plans and could use some suggestions.

    Draw Plus comes with a library of architectural parts that really
    help in doing floor plans.  There are doors, windows, appliances,
    furniture, etc.  There are also corners to create walls in 6" and
    8" thicknesses.  It took a while to figure out how to use them,
    but I eventually got the hang of it.
    
    I only wish the screen area was much larger, at a higher resolution.
    I get tired of having to keep zooming in and out all the time,
    resetting the grid size, etc.
    
    Randy
    

    Maybe a single 1024 x 1024 screen with only two colors would be
    a nice option.  The user could scroll around ala DPaint ][.
    This would only use 132K of chip memory, vs 128K for 640 x 400 x
    16 colors, so it seems feasible.
    
    The Amiga does understand larger bitbaps, doesn't it?
    

    Yeah, but scrolling around is still a problem, especially if you
    want to draw a single line that is longer than the screen area.
    
    I guess I just want too much...