Autocad 2007

Support Other Software
21

Wavada, your best bet for getting 3D from AutoCAD into blender is to create your 3D in AutoCAD as solid entities (ACIS solids). Then use the 3DSOUT command to export them to .3DS files. (This command may not still be in v.2007, tho…) The FACETRES variable controls the segmentation density of arcs/fillets for these exported solid entities. They come into blender as mesh surface entities, usually triangulated and usually duplicated vertices/faces (?) that has to be cleaned up in blender before its useful (like yellow says, for UV mapping & etc.)

But, again like yellow said, why not just import your 2D plan views and extrude those within blender and model your building there - its actually quite possible to get some accuracy in blender, too, as it allows you to type in unit distances (generic units) in mid-command as well as orthographic constraining by hitting the x, y or z keys mid command (double hit for local entity coordinate system). Once you get the hang of modeling in blender, it’ll probably go much more quickly than in Acad!

22

+1 to load cad files as images, than trace lines in blender. Non of the real cad files are directly usable in 3d modelling. This way or that, you will need to separate everything in different objects. Also if you model from images, you can get a more clean and organized model, this can help you in many different ways like reducing render times.

23

Well we all have our ways of modelling but printing CAD files to images, then loading the images to trace them is painful, pointless and unnecessary imo. It’s a poor mans work around for the inability to use or fear of CAD.

When CAD data is not available we either draw it from measured survey info, model directly in 3D or model from images like BbB’s link earlier or combination of all.

Blender has a perfectly good DXF importer and the whole CAD import can be layers -> Blender objects or just one object. Then model over that with planes -> loop cut -> solidify script -> delete original CAD object -> job done. Accurate, flexible, divided into objects as any other way of modelling.

There is no difference with regard to object organisation between modelling from DXF’s or images. Except snapping to DXF gives accuarcy and consistency over the whole model.

Scaling images of different elevations and floor plans to fit together with any degree of accuracy is painful.

You may say accuracy is not needed it’s all visual but why throw away accuracy when you can have it in the DXF’s and the ability to easily slot in revised detailing from additional DXF imports later in on.

So I totally disagree with your remarks regarding DXF import, it works for blender, sketchup, modo, Max and any other 3D modeller you care to mention as long as you have the DXF’s to start with of coarse. Modelling from DXF or DWG is common standard practice.

Wavada has CAD skills and DXF’s at his disposal converting to images is pointless.

24

Hi yellow, thanks for your answer. I think we are not working in same undustry. I’m not trying to ruin dxf importer, it doesn’t in a way fast for me.

I am a landscape architect and my main work is landscape visualization but i also make architectural visualisation and teaching software. I teached a lot of my school mates autocad and sketchup, i also teach sketchup in our chamber. I mostly use sketchup for cuboid or planar surfaces and using blender for organic surfaces.

I always start with survey or cad files (original vector files converted accurately) for boundries, walls and constant objects. When a project that designed and drawn by other atchitect comes to us its pain to figure out layers or blocks in our country.Take a look at that plan and imagine non of the plants in blocks or in organized layers. Also consider splines, unneccessery intersection cuts, wrong double lines, unclosed surface edges and so on. So not everyone draws clean. It comes to me more painfull to find little leaks or making surfaces with unncessery geometry. Modelling design decisions from cad files is a pain in landscape visualisation in our country.

I think blender is not good enough for archictural modelling or design. Sketchup is better for this type of job.

About accuracy, blender is a 3d visualization tool, not a 3d design tool. Sketchup is way better if you want to model in workflow that you described. Try snapping an objects bottom surface to a vertex on a terrain mesh. You need redifine object center in blender for accuracy, but in sketchup it doesn’t even matter.

Modelling from images will not effect your accuracy if you know what you are doing. You may say, due to image quality, modeller can not see the correct place of a line. This can be easily solved by increasing image resolution or seperating data in smaller images. Assume modeller draw a line 2 pixel to the west than the place its suppost to be, consider this causes a 10 (max 20) cm mistake in real life, assume sureyor with latest gps technology made 10 (max 50) cm mistake, you’ll get 20 (max 70-aprroximately 45) cm error in application, modeller even can be corrected the mistake that surveyer did. About buildings its not a even matter unless construction is based on visualisations. About architectural visaulisation a wall in golden square proportion won’t look bad unless you made a big mistake like using low resolution images or wrong z dimeonsions. In landscape application 0,5 to 1 metre difference is resonible if you think a dozer lowers the way it has been drived 0,01 to 1 metre.

For floor plans you can make more than one 3d window with seperate background pictures.

Modelling everything in one object in blender can be messy even in a small project.

About surveys, imagine modelling a terrain from contour lines. Filling all the faces is a pain in blender. After that if you want to modify the terrain, you possible need to retopo a subdivided face onto terrain but in the end editable terrain mesh won’t be accurate enough or really high poly. Also survey files are not clean as any other drawing.

I’m not trying to dictate my way or trying to use industry standards or change anyones opinion, just telling there is a work around. And non of my techical drawings or visaulisations has accuracy problems, poeple say i’m good at this.

Thanks for reading.