topic Re: Grid Reference System in AutoCAD Map 3D Forum

Grid Reference System

Craig_Swan — Wed, 20 Nov 2024 09:28:43 GMT

I have been asked to edit a previous drawing. The drawing already has a local map installed. I have been asked to add a grid reference system to this map, so that when I create an Object Data table, there will be a column (where pipework passes through) with grid refs listed. Hopefully, I am explaining this ok? I am new to Object Data and the Map side of things in Autocad. Below, I have shown the sort of Grid system I have been asked to do.

Re: Grid Reference System

imadHabash — Wed, 20 Nov 2024 10:17:40 GMT

Hi,

Make one of your grid lines known by numbers. Don't make the horizontal and verticals with alphapatical letters.

Re: Grid Reference System

Craig_Swan — Wed, 20 Nov 2024 10:54:23 GMT

Thanks Imad but I actually need to add a grid reference system to a DWG that already has a map on it. I need to incorporate this information onto Microsoft Access.

Re: Grid Reference System

ChicagoLooper — Wed, 20 Nov 2024 16:44:00 GMT

Hi @Craig_Swan

Your uploaded image shows AutoCAD Map3D symbol in the upper left corner, not plain vanilla CAD.

<<BTW, you should take this type of post to the Map3D Forum, you'll get better action.>>

If you have an understanding of Map3D, then creating a Map Book is a procedure that will create TILES of your overall map. Here's an 8-minute >>VIDEO<< by Jerry Bartels that explains the Map Book process.

If a Map Book is not what you want, then you'll need to create use the MAPREFERENCELAYOUTSYSTEM function which requires you establish a PROJECTION (coordinate system) beforehand. The reference grid and assigning a coordinate system are both completely different workflows so an understanding of coordinate geometry (map projections) will be highly beneficial.

Re: Grid Reference System

Pointdump — Thu, 21 Nov 2024 07:46:44 GMT

Hi Craig,
"...add a grid reference system to this map, so that when I create an Object Data table, there will be a column (where pipework passes through) with grid refs listed."
Can you elaborate a little? A screen shot showing what you want to do would be helpful to understand.
Dave

Re: Grid Reference System

Craig_Swan — Thu, 21 Nov 2024 09:29:56 GMT

Hi Dave. The problem is probably due to the fact I am jumping on the back of someone else's drawing, so I have no idea what software etc he used. I have never used Map3D before and was hoping for a quick fix. I only downloaded Map3D after lots of googling, as I felt it was something I may need. What I did last night, was to simply copy his reference grid (block) on his example drawing and paste it over the map on the drawing I have to edit. I had to scale the grid reference up to cover the map. On this basis, I would assume it is only lying on top of map and not linked to it, meaning at the end of my drawing when I need to create a data object table the pipework will not be associated to the grid ref system? Hope this makes sense? Again thanks for your time. I have attached his example drawing. I have to edit a drawing to make it similar to his attachment. The grid reference system he has used is in his model space but when I have tried to understand MAP3D tutorials (if that is the route I am supposed to go down) grid refs are only shown on paper space layouts. Has he just created a block of his grid reference system and if so, how has he managed to link it to his amp for object data extraction later? I apologise if I am all over the place here but hopefully there may be a more simpler way to the way he has set things up, rather than the way I have been explaining.

Re: Grid Reference System

Pointdump — Thu, 21 Nov 2024 10:47:58 GMT

Craig,
Thanks for posting your drawing.
"it is only lying on top of map and not linked to it"
Yes. It looks like quite a bit of your linework has Object Data, albeit <Null>, and you have several Object Data Tables already created.
Not sure where you need to go from here. What exactly are you needing to do? Create shapefiles? Pipe Networks?
Dave

Re: Grid Reference System

Craig_Swan — Thu, 21 Nov 2024 11:08:59 GMT

Thanks again for replying Dave.

Firstly, how did bring up that screenshot you sent , showing object data (albeit null).

His previous drawing that I sent as an example had object data linked to Microsoft Access as per below attachment.

Do you know by looking at his example if he used Civil 3D. I do not have Civil 3D. Thanks again.

Re: Grid Reference System

Pointdump — Thu, 21 Nov 2024 11:22:36 GMT

Craig,
Sorry, my screenshots were out of order. What I did was use command MAPEXPORT >> Lines and selected everything in "Link Templates" and "Object Data". That grabbed over 17,000 lines and created a shapefile. Then I drag-n-dropped that shapefile into the drawing. In Map Task Pane(command MAPWSPACE >> Show) I selected the Feature Layer and clicked on "Table".
You probably want something less than 17,000 lines. Also, this is the first time I've heard of "Link Templates". Your Access file must have been "linked" to the drawing. That looks like the data you want. Oh, and you don't need Civil 3D. Map 3D will work fine for this.
Dave

Re: Grid Reference System

Craig_Swan — Thu, 21 Nov 2024 11:25:36 GMT

Thanks Dave, appreciate the feedback.

Think I'm just going to crack on with drawing works then worry about the object data at end!!☺

Take care and thanks again pal.

Re: Grid Reference System

parkr4st — Thu, 21 Nov 2024 17:11:21 GMT

The project will work with SDF data and Georeferencing to provide location on a map.

Go here: https://data.edinburghcouncilmaps.info/search?collection=dataset&tags=open%2520data

The base map data for the area from that site is available as "Adopted Roads" in the .ZIP

That data is on OSGB1936>NationalGrid. Meters

Copy and pasted you Potable Water Mains layer into the map using COPYBASE and the center of the roundabout at B701 and Redford Road and Dreghorn Link. It fits well IMHO. Did the same with Backgound_Boundary_Service_Area. Also fits good IMHO.

The fit needs to be confirmed from ground point data to be real accurate! Fitting the data with map tools may be necessary.

Then mapexported those layers to two SDF files and built the attached EdinburghMap .dwg.

Added a 100 x100 (Meters) grid and mapexported to SDF also. Added to map

MapGISOverlay Identity of the Mains and the grid and the result is a data table with each section of main within each grid polygon.

So now which layers have the object data you need to work with? Repaeat the copy and past of the layer, MAPEXPORT with the OD needed and then add to the map and run the Identity again with taht layer and the grid.

Post your questions.

Re: Grid Reference System

ChicagoLooper — Thu, 21 Nov 2024 18:04:47 GMT

Hi @Craig_Swan

Be prepared for an answer I positively know you won't like.

You can't do it with out-of-the-box Map3D tools. AutoCAD Map3D doesn't have the built-in capability to do that, no matter how or who, desperately tries to justify workflows to the contrary. You'll need 3rd party software to LINK the individual pipes and parts to a 'named' grid cell. I told you you wouldn't like it, right?!

<<Alternatively, you may manually link each individual pipe object to a named CELL in the GRID but that's not an efficient workflow and painfully time consuming.>>

Your sight is in Edinburgh, correct?

Your site is referenced to OSGB British National Grid, right?

Your drawing didn't have an Assigned Projection, but if you use MAPCSASSIGN, you can manually give your map the coordinate system known as EPSG 27700 (OSGB1936.NationalGrid) then turn on Bing Aerial to verify the geospatial position. See image-201.

Image-201. MAPCSASSIGN the projection EPSG 27700 to get Bing imagery.

Once the geospatial position is established, you may use MAPREFERENCELAYOUTSYSTEM command to create a Grid linked to the viewport on your Layout Tab. See image-202. The Grid can have 'cells' sized 100meters X 100meters, or any cell height/width you want. The cell size you choose is under your control when using this command. See image-203.

Image-202. Go to Layout Tools Tab.....

Image-203. .......control settings for cell size.

If you assign the projection EPSG 27700, then the graticules (ticks and labels) can be linked so they're consistent with the northings and eastings values of the projection. Since both the ticks and labels are linked to the assigned projection, panning (or zooming) of your VP will update the coordinate values that surround your VP. See image-204 and image-205.

Image-204. Northing and easting values are 'LINKED' to the viewport AND your assigned coordinate system.

Image-205. North and Easting values are automatically updated when the VP is moved to SW. Compare values with Image-204.

You are correct when saying the original author's object data is linked to a reference grid in his modelspace, not his paper space layouts. However, his modelspace grid and the objects linked to it are not part of the typical Map3D toolset.

Regarding his Object Data, experienced Map3Der's can create Object Data in various ways. If you upload the original drawing and any Access/Excel file, then a thorough evaluation can be undertaken and a viable workflow can be provided for your specific drawing. Can you upload the original drawing and associated data files? Or privately share them through DM?

Re: Grid Reference System

ChicagoLooper — Thu, 21 Nov 2024 19:27:24 GMT

@Craig_Swan

Believe it or not, that Grid is not good. It should be improved. The original author used letters for both vertical and horizontal axes. He should've used both letters AND numbers; e.g., Microsoft Excel uses numbers for Rows and letters for columns.

In the Grid section named AF, so does that mean Column & Row or Row & Column? It makes a difference. Especially to steel toes and hardhats in the field, not those sitting at a desk like you and the original author. Section AF is NOT the same as FA and misinterpretation, even if such misunderstanding is not your fault, will be confusing. Although your Cad workflow is admirable, confusion may result in co$tly error$ and your boss nor your client will like it, especially if it was totally preventable. Offering a better solution is perfectly acceptable and likely preferred. Simply using the data As-Is, is neglect.

Also, in a screen grab from your uploaded image--focus on Red highlights vs. Green highlights.

A pipe highlighted Green is completely inside a Section because it begins and ends in the same Cell.

A pipe highlighted Red starts in one Cell and ends in another.

Bad Examples Highlighted in Red:

1. A pipe starts in FC and ends in FD. The designated Section is FC. Does it leave the impression that it's NOT in FD? How does this translate to a worker in the field?

2. A pipe starts in GE and ends in ED. The designated Section is FE, which is neither a beginning or ending section. Will this affect pipe installation? Will it be costly?

I understand you are trying to put this data into Access but your workflow is trying to put BAD data into a GOOD workflow. Impress your boss and improve the original DATA. Your map can be presented in a better way but you must be courageous enough to replace bad data.

Re: Grid Reference System

Craig_Swan — Fri, 22 Nov 2024 12:00:33 GMT

Really appreciate your feedback. I'll get my head into it.☺

Re: Grid Reference System

Craig_Swan — Fri, 22 Nov 2024 12:01:30 GMT

Will give this a whirl this afternoon. Can't thank you enough for your time and response. Thanks again, it is appreciated.

Re: Grid Reference System

Craig_Swan — Mon, 25 Nov 2024 09:54:46 GMT

Morning, sorry to pester you again but I have been thinking about my predicament all weekend.

I am going to start again with what I need to do and I will attach the items I have and if you would be so kind to advise my best solution? Here goes (if I repeat myself , I apologise):

I have been given someone else's drawing (attached) and been asked to show a grid reference system on the map on the drawing. The drawing shows numerous service pipework layouts and I have to to have an object data list associated with the drawing which will include several columns of information including a column showing lengths of pipes and where they are located in relation to the grid system. I have attached a screenshot of a previous list (compiled by others using Microsoft Access software) to give you an idea. I could not attach the actual object data list as I am getting a message saying "file type .mdb not supported".

Now, here is where it unfortunately gets messy.

I have recently downloaded Map3D but have NEVER used it before, as I work in the ducting industry and mapping drawings were never required.

What I am basically asking is....... what is the best way for me to add the grid ref system and link object data list to the drawing?

I am not restricted to the way it has previously been done ie Microsoft Access etc. The way it is to be done, lies firmly with me. As with most Autocad queries, there are 100's of methods to do something and everyone has their own way of carrying out tasks. Head is at bursting point!! ☺

Re: Grid Reference System

Pointdump — Mon, 25 Nov 2024 14:50:34 GMT

Craig,
This Forum will accept pretty much anything zipped. Maximum file size 71MB.
Dave

Re: Grid Reference System

Craig_Swan — Mon, 25 Nov 2024 14:53:29 GMT

Thanks Dave, new to the forum.

Re: Grid Reference System

ChicagoLooper — Mon, 25 Nov 2024 15:30:50 GMT

Hi @Craig_Swan

You have two (2) issues with your uploaded DWG: (1) It's not properly georeferenced and (2) You didn't upload the Access database file. <<Object Data cannot be created if you don't attach the Access database.>>

To properly georeference the drawing you uploaded:

Select ALL objects=>enter SCALE on command line=>for Basepoint enter 0,0=>for Specify scale factor enter 0.001 ENTER. <<This will 'Scale' the Northing and Easting coordinates by 1/1000 and MOVE all objects from their CURRENT modelspace position to a location relative to the Equator and North Pole.>>
Next, enter MAPCSASSIGN on command line=>in Search Box enter 27700=>select (highlight) the result of the search=>click ASSIGN button at bottom of window.
Finally, go to Geolocation Tab=>Online Map Panel=>Change Map OFF to MAP HYBRID.

<<Steps 1 thru 3 above will properly georeference your drawing and put it in Kyle of Lochalsh. The geolocation is verified when turning on Bing imagery.>>

Once the drawing is accurately georef'd, you can concentrate on creating a GRID System.

FYI,

you don't necessarily have to upload the Access database. If you choose not to upload it, then your objects won't have the OTHER data (the tabular data) shown in your uploaded image.
The GRID procedure you wish to undertake is an ADVANCED AutoCAD Map3D concept. If you don't have any background in Map3D then be forewarned, you might be in for a long haul. The GRID workflow will likely use geospatial concepts and they do not resemble concepts typically used in plain vanilla Cad.

Re: Grid Reference System

Craig_Swan — Mon, 25 Nov 2024 15:47:43 GMT

Thanks again for the feedback.

It all makes perfect sense.

If you yourself were to add a grid referencing system to one of your drawings, would the Map3D route be the one you choose? In your opinion, do you think it would be worth my time to learn Map3D, keeping in mind, there is very little of this type of work I will do again?