LISP to extract coordinates of bottom left and top right corners of a map or 3D model
@MattAAM wrote:
... I'm trying to extract 2 coordinate points for the bottom left and top right corners of a 'bounding box' surrounding the geometry (including blocks, lines, surfaces, etc) inside each CAD file.
....
If that geometry is all there is inside each CAD file, then the bottom left and top right corners are directly available, as the EXTMIN and EXTMAX System Variables. Do a ZOOM Extents before you extract them, because certain changes in the drawing may not be reflected in those System Variables until you do.
If there's other stuff that would make those not what you're after, but you want to select things, DrawBoundingBoxMult.lsp >here< will find the collective bounding box of multiple objects [and there are other routines out there that will do the same]. You can just omit the drawing of the rectangle from it, but use the rest to get the LL and UR results.
I'm not versed in pulling information from drawing files without opening them. I couldn't say whether things like those System Variables are available in that way -- it could be that they are not stored in any way, but are simply a result of what is stored, and therefore may not be extractable.
But I do expect that if they are, the ZOOM Extents thing I suggested would not be necessary. I tried changing something in a way that changed the extents but did not affect those values [awaiting a Zoom Extents to update them, which I didn't do] and then saving/closing the drawing. When I reopened it, the values were updated. So in a just-opened drawing, that Zoom is not needed.
DBBM could easily be adjusted to just use everything, but you can also just type in ALL at its selection prompt. It could be made to automate that omitting Text [& Mtext? & Multileaders?] if you like.
