Planning your Project

[garethace]

I just read a couple of articles about this in the http://www.augi.com monthly magazine on the value of planning how to do your project in CAd before diving in. This seems to be a very consistent theme to many article on that web site about using AutoCAd - some of the contributors come from a wide variety of backgrounds and have been all using CAd now for years. So I guess they have learned a thing or two down through the years.

 

My pet hates are:

 

Having spent a month on a project, and working up final versions, only to find yourself stuck with the very mistakes, or panic actions someone, you might not even know, made weeks before hand, when that initial digital survey was first loaded into your CAD program, rotated, layers messed all up, duplicated, 'meshed' together with other surveys poorly etc, etc.

 

Or god forbid, I only yesterday have been witness to a full planning application, where the survey was not only scaled - something which is dodgy to do to begin with - but worse, noone even bothered even to get one quick measure on the ground to make sure it was right. So now the architects have a whole building design and 'signed off' which is about 1 and a half times bigger than the size constraints of the site will allow for!

[Jeff Mottle]

So now the architects have a whole building design and 'signed off' which is about 1 and a half times bigger than the size constraints of the site will allow for!

OMG! I hope this is not a big project...I see lawsuits and bankruptcy in that firms future if it is.

[garethace]

We are doing the site right next door Jeff. I just asked the architects for their site plan, to XREF into our application, as the site boundary line was to be defined by splitting up a single plot of virgin land, (no real boundaries existing) one bit for us and another for them.

 

We had also done another building across the road, so I knew our dimensions were correct. All I wanted to do was define where the edge of out site was, according to this new line dividing up the single plot.

 

What I actually got, was a lot more than I bargained for.... they have designed a really nice building, to a high level of design and put alot of work into it with the client etc, but the site they designed for doesn't even exist on the ground. Clients pay good money for this kind of a service too.... little wonder the 'whole architecture' thing never really took off as a service here in this country. I know architects who worked as waiters/barmen for years.

 

Sometimes, it is hard to beat the pair of walking boots and a humble measuring tape Jeff. Like I said in the original post, bosses would really want to pull their heads out of their back sides and actually wake up to the need for CAD users, who are responsible, intelligent and motivated.... not ones who are just going to pass the buck down the line. Probably will never happen though.

 

A particularly nasty boss I once had deleted the whole CAd files from the server of a competing architect who had just left. The poor old builder went to site and constructed the building without actually having a drawing! This is par for the course now here in Ireland - a CAd wild west.

 

Standard proceedure is to blame everything on the latest person to leave the firm, training or even the concept of CAD training is non-existent. I regularly watch guys who have a software CD license worth €5-6,000 sitting pretty on their desk, while they design whole projects using cracked software.

 

What I object to totally, is my being a good CAD person, to have to be forced down directions and into situations I wouldn't even send my worst enemy now.

[STRAT]

i never never EVER use my collegues' cad drawings to work off. NEVER!!!

 

because in my experiance i'm yet to find in 15 years, an architect that can draw properly. or more to the point, accurately. lines arne't exactly square, verticles can be like 0.005 of a degree off, offsets arent accurate, 5mm is drawn not at 5mm but at 4.3465mm, lines dont extactly meet or the ends overlap. you get lines drawn upon lines upon lines. etc etc etc. the list is endless.

 

i've often thought to save time i'll use a predrawn cad plan from the architect - i mean, it looks fine from initial looks. but like a month or so into the 3d drawing i find the original 2d cad plan to be a load of crap, making my 3d mesh a far from perfect model. my own fault trusting a drawing not done by me, but i find if you want something done correctly, then do it urself.

 

thats my pet hate - architects' cad drawings (or non 3d artists' drawings)

 

ideally a 3d mesh has to be perfect in every shape and sence to allow optimum performance out of it. nothing ever gets drawn perfect, but we as 3d'ers should strive that way.

 

non 3d'ers, imho, havent got the first idea.

 

sorry to rant on, but thats a massive pet hate of mine

 

(****STRAT gets off soap box****)

[garethace]

Would make you wonder about a product like ADT then, which is really a mesh which is designed to get dimensionally accurate 2D blueprints, which you can build from. Imagine the mess if you went down that road with proper training and allocation of roles and responsibility....

[Jeff Mottle]

because in my experiance i'm yet to find in 15 years, an architect that can draw properly. or more to the point, accurately. lines arne't exactly square, verticles can be like 0.005 of a degree off, offsets arent accurate, 5mm is drawn not at 5mm but at 4.3465mm, lines dont extactly meet or the ends overlap. you get lines drawn upon lines upon lines. etc etc etc. the list is endless.

Can I have a halalulua! Amen to that! I've done that SOOO many times only to find, as you have as well, nothing lines up 1 month down the road. I honestly have wondered if they thought CAD was a piece of napkin paper and the snap tools were just for fun. I swear there should be licenses for CAD operators. You can't drive a car without training, why is it ok for Architects to pretend they can drive a CAD application.

 

Although I've seen some pretty bad work by CAD techs too. In fact I've onyl se work from about 2-3 people in my career that I thought was good.

 

I've seen dimensions off by 10 feet from floor to floor. In the process of doign one rendering job I actually had contruction halted becuase of errors I found doing the renderings!

[STRAT]

but then we dont use ADT for it's designed purpose. we only have ADT so i cant draw my 3d models. thats where they stay, in my pc (or on the network).

 

the production drawings are all dont in acadLT. even tho the drawings aren't accurate, they still accurately dimensioned up to build from.

 

if the drawing is innaccurate to dimention from, the technitian manually updates the dimention string.

 

cock-eyed or what? i find it's a combination of not learning to draft properly and lazyness. and i sevearly hate lazyness in cad drawing.

[UDM Designer]

I am currently one of those CAD monkeys who sometimes is let loose on some 3d work, which is what I prefer to do. But here at our firm we draw every little detail and make sure that it is square and that things line up. Since this is the only experience I have with Arch firms I figured they all did drawings with the same precision. After reading this post I guess I'm wrong. I am currently starting to do some freelancing and I will keep this post in mind. I feel sorry for the company that messed up but thats a huge mistake. Thanks for the post it will keep me on my toes.

[STRAT]

yeah. this certainy is good advice for freelancers -

 

if architects provide you with their own cad drawings, check them with a fine tooth combe. infact, personally speaking, i'd draw them up again from skratch. this will save you a world of hurt further on down the line. and it will happen.

 

3d guys really need to draw as accurate as possible. architects dont because they back up their drawings with dimensions, usually manually added. officially you should never scale off a drawing, so i guess thats why. but we all do dont we. just be carefull not to get caught

[Chad Warner]

I never understood the sloppy cad files we get. I think out of all the projects I've done, I've gotten one correct set of drawings. It seems to me it would be much harder to draw non-orthaganal, non-dimensioned lines (4'-5-3/32" vs. 4'6").

 

-Chad

[STRAT]

hehehehe

 

you funny americans still using that crazy imperial measurement system

[Chad Warner]

Probably only makes it worse for the inaccuracy of the drawings.

[William Alexander]

You guys are missing all of the fun. This kind of thing is borderline on physical abuse for those actually doing the work!!! No body listens in the field either, the architect is always right (legally anyway) yadayadayada.

 

I build a dormer type roof three times over a 45 degree box bay, residential. Told the expeditor it's drawn wrong- do it the way the architect drew it- OK. Well that did'nt work, expeditor spoke with architect- he had some different idea- I said no it still won't work. Rebuild it agian- still did'nt work. Architect came out in his brand new black corvette, circa 1989, reviewed the situation- He actually admitted he was wrong / drawn wrong- The admission most likely because he got caught and wanted to cya his 250k/yr bread & butter work from the builder.

 

What did I get for being a "good little" subcontractor- paid for my time, but lost money on the crew working at a different site. When the Boss is away......

 

Strat- So trry to temper your frustration. Each face could weigh 60lbs, editing it is very itchy, a cut is like brezier spline never striaght, and you are doing it outside facing south, middle of summer, 90 degrees, 90% humidity, 5 mph breeze (when it blows), and hung over because you have had it with this stupid crap that should never have been. - It could always be worse LOL.

 

 

UDM Designer- would you be willing to tell what firm you work for? I would like to know just for reference- Just to believe that a firm works like that in this area would make my day. Maybe its that polluted fowl lake, your drinking water source, that caused this level of accuracy. hehehehehe

 

WDA

[ch83575]

That's strange, I have always thought exactly the opposite. I always strive for perfect drawing in my cad drawings at school so all of the dimentions could be dynamicaly generated, not manualy inputed. In 3d i have always felt that if it looks right, then it is right. After all it is only a picture; right? If you are going to build something then the dimentions have to be right and things cant over-lap... at all! If you are building a 3d model so what if the wall sticks 1" thru the ceiling? All you will see is a sharp corner where they meet, so what if it isn't perfect.

 

When i am doing something 3d if it looks funny then i change it. If it looks ok... and it is actualy 1" off; who cares? I am only making an image. Let the architect make the perfect drawing with the acurate drawing. Builders might try to measure to scale off a plan, but they sure as hell wont be trying to pull a dimention from my renderings!

 

Just my take.

Chad

[William Alexander]

If you are building a 3d model so what if the wall sticks 1" thru the ceiling?

Well it does kind of- maybe not so much in autocad renders-but look at the GI here:http://www.cgarchitect.com/resources/tutorials/wda/tutorial1.asp

 

WDA

[ch83575]

Maybe it makes a major difference in radiosity, but i have been working exclusively in mental ray for a while now. It seems, even from your tutorial, that mental ray is almost geometry independent; is this right? The standard ray-tracing algorithem is per pixel, not per object, and it seems like all lighting solutions that are based on raytracing (photon maping and final gathering) would not care if your wall stuck into your ceiling geometry.

 

This is how I have been thinking about it, if i am doing something the wrong way (i concider anything that would slow down my render "wrong"), I would like to know.

 

Thanks,

Chad

[William Alexander]

would not care if your wall stuck into your ceiling geometry

 

If you like, A new thread, maybe in order. Rather than going off on a tagent of this one.

 

But if that wall sticks above and recieves a photon (interior/exterior) above the ceiling line the energy is radiated into the room down the wall, based on Photon size and final gather size. Do you use less than 1" photons or 1" regather max size? Even two seperate surfaces that are on the same plane and close or adjacent tend to recieve the some of the same photons. It's pionted out in the tut (differentiation based on proximity problem?).

 

With ADT walls, the miter at the corner recieves photons and light mapping, even though not visible. So that information has to be processed, needlessly and can cause normal errors with MR if the geometry happens to intersect further slowing down the GI processing.

 

Good cad drawings should make planning the modeling in cad for max or in max a breeze, you can trust the info in your case so....

 

If your line drawings are that accurate and accuracy is in the workflow why would a wall be 1" above a ceiling plane anyway? Well I know....... however sooner or later that habit will bite ya, just when you need to get a complex scene out the door-It will rear it's ugly head!!!!!! Should-a would-a could-a .....ooops to late now. The law offices of "we screwem and howe" are on the phone.... I'm being very extreme but there is some truth to it.

 

If you want, lets move to the Max forum.

 

WDA

[ch83575]

You can move the off-topic posts if they would fit somewhere else better, but I would think that my questions are more MR based than max based, especialy as most of my experience is with Maya not Max. Well, here goes:

 

I dont understand how any photons can be stored behind occluding geometry. It seems that if you have two pieces of geometry overlaping and a photon strikes almost at the corner, then yes, part of the photons radius will be 'stored' in the interstitial space. But that radiation will never be sampled, because no visible ray (be it primary or secondary) will ever sample that section of geometry because of the occlusion, right? This, of course, is as long as all geometry we are talikng about is opaque. If any transparancy is present then all sorts of problems occur, and I agree in that case it would kill render time due to the huge numbers of reflections and refractions from overlaping geometry.

 

My point is this: every photon must be stored. This process is VERY fast. The slower part is the sampling of the photon map, and the map can not be sampled anywhere where occluding geometry prevents any visible rays from taking a sample.

 

Am I still thinking about this wrong? Have you noticed a real world difference in rendering time? I am now very intrigued.

 

Chad

[STRAT]

That's strange, I have always thought exactly the opposite. I always strive for perfect drawing in my cad drawings at school so all of the dimentions could be dynamicaly generated, not manualy inputed. In 3d i have always felt that if it looks right, then it is right. After all it is only a picture; right? If you are going to build something then the dimentions have to be right and things cant over-lap... at all! If you are building a 3d model so what if the wall sticks 1" thru the ceiling? All you will see is a sharp corner where they meet, so what if it isn't perfect.

 

When i am doing something 3d if it looks funny then i change it. If it looks ok... and it is actualy 1" off; who cares? I am only making an image. Let the architect make the perfect drawing with the acurate drawing. Builders might try to measure to scale off a plan, but they sure as hell wont be trying to pull a dimention from my renderings!

 

Just my take.

Chad

you are correct, but you miss my point.

 

a 3d visualiser does not have to be millermetre perfect. as long as the proportions are correct who cares? or even knows if i havent drawn a wall to the correct length?

 

my point was about a messy mesh. overlaps and untrimmed lines, faces that extend through each other, lines over lines etc etc etc.....

 

no only do these make for a nightmare to work with, but they DO make a difference in rendering. you get all sorts of problems occure, like (as mentioned) GI sdolutions can go to pot. shadows can seriously mess up, and most commonly, light leakage occures. and these are serious points in all renderers.

 

i only mentioned that example about an architect drawing a 5mm line at 4.5003945mm because i'd naturally assume it's meant to be 5mm, so when i draw my 3d model on the assumption the architect draw his original line at 5mm and it's not, i get problems further on down the line. if he's input a 5mm dimension but the line isn't quite 5mm then thats a hangable offence in my books. and this is a common every day thing.

 

thats why i cant rely on what i get. it's bad draughtsmanship and lazyness.

[IC]

When I started training as an Architectural Technician, AutoCad had just become popular with the masses and my company bought two seats. (I didn't get to even try it for a year or so as my boss said I had to learn manual draughting first-I'm very glad of that now.)

 

The general thought was that there would never be a mistake on a drawing again but the margin for error is, of course, just the same as with draughting.

I've seen people add dimensions to a digital drawing and then 'correct' the numbers rather than the drawing!

 

I'd echo Jeff in having coming across only two or three people in the last ten years who draw 99.9% accurately and you'll find that's how they did it on a drawing board.

[garethace]

i only mentioned that example about an architect drawing a 5mm line at 4.5003945mm because i'd naturally assume it's meant to be 5mm, so when i draw my 3d model on the assumption the architect draw his original line at 5mm and it's not, i get problems further on down the line. if he's input a 5mm dimension but the line isn't quite 5mm then thats a hangable offence in my books. and this is a common every day thing.

 

thats why i cant rely on what i get. it's bad draughtsmanship and lazyness.

 

 

Talking of hangable offenses, to update you guys on my building problem with scaling surveys etc. Today, I noticed that people had for a change gotten really bothered about the 'correctness' of the CAD drawings.... a stream running directly in front of the site, wasn't ignored anymore, by just saying 'ah! it is there somewhere'... I had to spend a day more or less tidying up the survey drawing, to make full sure that certain things 'weren't just lost' or obscured or otherwise misinterpreted during the course of the design process.

 

This meant standing back from the drawings carefully and considering what was distracting, and try to go back all the ways to basics, i.e. divide drawings with different design goals, like say landscaping and parking, service access, general site strategy design options, surveys, adjoining building plans, internal fit out.... all put some way that wouldn't mess up later.

 

Interesting how it took a disaster, next door to make people realise something really decent had to be done, isn't it? I just did a quick calculation today - the building next door was meant to be for small businesses and craft workshop etc, etc. Divided into several units of 180m squared (1936 sq ft). But it turns out now, these units are only in fact 108m squared (1162 sq ft) each.

 

What do you reckon people? I am not very good with areas myself, the use proposed for these units was workshop/artisan/small cottage industry or incubation units for want of a better description. All very state funded and prestiguous in its own way - for the people of the region of this country here in question. The original scheme shows a possiblity of building roughly ten or more of the above units, now, I think they would be lucky to fit it 3 or 4 and have room still left to move around.

[garethace]

On the subject of drawing with accuracy.... here is what I think about AutoCAd, what is unique to AutoCAd... and bear in mind you learn this stuff on the very, very, very first week of AutoCAd classes....waaaaayyyy back.

 

Offsetting and trim is one of the more powerful tools you can use in AutoCAD - that is how you draw with AutoCAD.

 

I have to get more used to this way of thinking for working with accuracy in a design practice. If your drawing style, allows it combine this with XLINEs in AutoCAD and you can make things very accurate indeed.

 

The offset command in MicroStation isn't bad - but is still not 'they' command to know/use a lot and properly in MicroStation.

 

In fact, in MiniCAD or Microstation, I don't think offset really features at all that much.

[garethace]

Undo seems to be a very important command in AutoCAD and selections, selection 'previous' and selection removal all seem key to knowing how to work in AutoCAD.

 

I think that UNDOs are improved in 2004 also.

 

This is simply not the case in other CAD softwares.

[garethace]

I think we should really begin to use AutoCAD forum a bit like tips section at this web site - as they say a picture can tell something and just get the point across a way more quickly.

 

What do you guys think?

 

http://www.spaug.org/Tip_Month.Html

[Fernando Lino]

I am working with 3 more people on one project and I found a lot walls with 89.125837494E+10 degrees (we use ADT) ...I'd like to know if "Ortho(F8) for dummies" is available.