bhatch visible and non-visible areas

[Jabba]

This may be a very basic question which may or may not have a very basic answer!
When using the bhatch command and picking points in a selected enclosed area, of which all of it is not visible within the screen area, I get a Boundary Definition Error of Valid Hatch Boundary not found - this is very annoying especially as I have narrow, long areas to hatch.
Anybody help?

[CADTutor]

Yes - unfortunately, the Boundary and Bhatch commands both find contiguous areas by analyzing the screen image rather than AutoCAD objects. That being the case, they only work successfully if the entire area you want to hatch is visible on the screen.

[Jabba]

..does this mean that there is no easy solution to this problem?

[fuccaro]

Well, if you can not solve a problem try to walk around.
Zoom in close enough and draw a line with an end inside of the area. Make the line "long enough" to work confortable -zoom out if needed.
Zoom out to see all the area to be hatched on the screen. Start the BHATCH command and select PICK POINT. With the correct OSNAP settings you will need to point the line (and maybe press TAB several times) to indicate the desired point.

Other solution:
Zoom in and enter at the command prompt:
(setq a (getpoint)) Zoom out and start the BHATCH command. Select PICK POINT and while AutoCAD expects a point enter at the command prompt
!a

If the boundary you wish to hatch contains just a few elements (plines, lines) you may try to hatch with the SELECT OBJECTS method and pick those boundary elements one by one OR with a window selection.

[Jabba]

Hi fuccaro
Im using AutoCAD 2002 LT and the (setq a (getpoint)) code you suggested will not enter at the Command line.
Dont quite understand your first solution , can you expand and clarify?

[fuccaro]

The (setq...) is an AutoLisp expression but AutoCAD ...LT will not recognise it.
If it is difficult to pick a point inside of an area, draw a line having an end point inside. When AutoCAD expects a point from you, just answer: "the point you ned is the end of this segment". If the line is long you can select it confortable. Set osnap to endpoint and when you move the cursor over the line the end point will be selected. If it is the other end, press TAB. When the right end point is selected, click.

[Jabba]

Hi fuccaro, thanks for the info to date, but - how do I enter "the point you need is the end of this segment" when the command requires a point inside the hatch area? - I have't come across this method of entering info before...

[Kate M]

Jabba,

I usually zoom out, so I can see the whole area to be hatched, then start the command -- then zoom in close enough to use the "pick point" method. It seems that as long as the whole area is on the screen when you *start* the hatch command, you can zoom wherever you need to *during* the command.

[AndrewJ]

As a last resort for hatching an awkward area you may consider drawing a temporary pline around the area you want to hatch and hatch by "select object"...

[Jabba]

Thanks for all your useful replies - Im sure I shall be successful using one of the methods suggested!

[hyposmurf]

I usually use select point,if that doenst work Ill select the objects and if this also fails I'll end up creating my own boundary as described above.If your drawing has lots of complex hatching where you wnat to try freezing the layer the hathces are when you go hatch,should make AutoCAD's job easier analysing all the drawing data,sometimes it can be too much.