Using blocks and layers
Posted: Thu Jan 16, 2014 1:44 am
Hi,
I'm just starting out using QCAD (and CAD in general) to design a garden shed (while dusting off memories from 20+ years ago of technical drawing at school).
Using QCAD I've been combining elements into blocks of parts before placing them into layers but feel like I'm missing something about how blocks and layers relate.
I've got a layer for the roof section, a layer for the front, another for the side elevation. I'd been drawing parts on the relevant layer and selecting them to create a block. Then at some point I noticed that strange things happened when making some layers visible, some parts would appear when they shouldn't and others disappear when they shouldn't (AFAICT). Then I noticed that some lines within blocks were allocated to a different layer than the block was, and that allocating them to layer 0 seemed to fix it.
I then proceeded to make sure the lines of each block were set to layer 0. I came unstuck with this method however when I then wanted to draw some of the hidden lines of parts as dashed rather than solid lines. I then had to break my all-lines-in-block-on-layer-0 rule in order to achieve the desired linestyle.
Uh. An idea just ocurred to me, probably from viewing viewtopic.php?f=47&t=1992 - I should create some layers purely for use within a block, but no drawing should otherwise go there - Outline, Center, Hidden etc, while other layers might be for major elements of the design - Roof, Base, Wall, Door, etc. That makes more sense anyway than how I was looking at it..
Just curious also if one generally splits the elevations into different layers or combines them into a single elevation (ie roof vs roof-plan roof-south etc)?
Also, I sometimes create a block for a part and then later realise that some other part will partially obscure the first part and then have to go back and edit the lines to change them to hidden lines, or I need to duplicate the block because not all will need changing. Is there a way for QCAD detect when an object is hidden and change the line style accordingly?
Thanks,
Terry.
PS, "duplicate block" would be useful.
I'm just starting out using QCAD (and CAD in general) to design a garden shed (while dusting off memories from 20+ years ago of technical drawing at school).
Using QCAD I've been combining elements into blocks of parts before placing them into layers but feel like I'm missing something about how blocks and layers relate.
I've got a layer for the roof section, a layer for the front, another for the side elevation. I'd been drawing parts on the relevant layer and selecting them to create a block. Then at some point I noticed that strange things happened when making some layers visible, some parts would appear when they shouldn't and others disappear when they shouldn't (AFAICT). Then I noticed that some lines within blocks were allocated to a different layer than the block was, and that allocating them to layer 0 seemed to fix it.
I then proceeded to make sure the lines of each block were set to layer 0. I came unstuck with this method however when I then wanted to draw some of the hidden lines of parts as dashed rather than solid lines. I then had to break my all-lines-in-block-on-layer-0 rule in order to achieve the desired linestyle.
Uh. An idea just ocurred to me, probably from viewing viewtopic.php?f=47&t=1992 - I should create some layers purely for use within a block, but no drawing should otherwise go there - Outline, Center, Hidden etc, while other layers might be for major elements of the design - Roof, Base, Wall, Door, etc. That makes more sense anyway than how I was looking at it..
Just curious also if one generally splits the elevations into different layers or combines them into a single elevation (ie roof vs roof-plan roof-south etc)?
Also, I sometimes create a block for a part and then later realise that some other part will partially obscure the first part and then have to go back and edit the lines to change them to hidden lines, or I need to duplicate the block because not all will need changing. Is there a way for QCAD detect when an object is hidden and change the line style accordingly?
Thanks,
Terry.
PS, "duplicate block" would be useful.