My drawing loads very slowly and is slow to work with. This might be caused by very dense hatch patterns in the drawing. How do I solve the problem?
Drawing with very dense hatch patterns
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andrew
- Site Admin
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Drawing with very dense hatch patterns
From a QCAD user:
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andrew
- Site Admin
- Posts: 8838
- Joined: Fri Mar 30, 2007 6:07 am
Re: Drawing with very dense hatch patterns
1. Select all hatches which are not solid fills using the selection filter (View > Selection Filter):
2. Change the hatch pattern scale to something reasonable. Start with 1, if the performance is OK, try 0.1, 0.01, etc. to find the smallest reasonable pattern scale.
- select_hatches_with_patterns.png (24.34 KiB) Viewed 231 times
- change_pattern_scale.png (90.98 KiB) Viewed 231 times
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CVH
- Premier Member
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- Joined: Wed Sep 27, 2017 4:17 pm
Re: Drawing with very dense hatch patterns
Ideally we would work out a Hatch-segment density.
Or how many segments it takes to render 1 squared mm.
Knowing these are all line-segments or dots and are rendered in the associated Lineweight in mm ...
... We can avoid to invoke the Hatching-engine on a too dense pattern in a given scale.
Beats a boundary 'Complexity' factor and 'Timing-out' for each Hatch before it ever occurs.
But you need a good insight in CAD patterns to do so.
Invisible Hatches because too dense, too complex, because timed out, only slow down QCAD.
We once worked out a 'Cloning Load' factor, when too high the pattern would fail the QCAD Hatching-engine.
They are also mysterious things to select, regardless of even knowing that they exist in a drawing.
With the same ease the Hatching-engine can revert to filling it solid for the time being.
Or at least warn the user, once on loading is enough.
Like warning that there is 3D data in a drawing, except for QCAD/CAM.
The required Hatch for this test and the next one has a density of only 1 segment per mm at unit scale.
The Add-On deliberately uses the hatching engine to fill an entire area.
In scale 0.08 that are 12.5 parallel segments per mm, quite harsh but still feasible if you max out the 'Timing-out' preference.
HJ Seef requirements for this tool are near the limit of what is possible based on his 'White paper'.
Both tests produce over 10k segments in an Hatched area not larger than 78 by 124mm.
Zig-Zag pocketing for reasonable tool diameters is thereby implemented.
A larger Laser spot would be a good idea in his case.
Regards,
CVH
Or how many segments it takes to render 1 squared mm.
Knowing these are all line-segments or dots and are rendered in the associated Lineweight in mm ...
... We can avoid to invoke the Hatching-engine on a too dense pattern in a given scale.
Beats a boundary 'Complexity' factor and 'Timing-out' for each Hatch before it ever occurs.
But you need a good insight in CAD patterns to do so.
Invisible Hatches because too dense, too complex, because timed out, only slow down QCAD.
We once worked out a 'Cloning Load' factor, when too high the pattern would fail the QCAD Hatching-engine.
They are also mysterious things to select, regardless of even knowing that they exist in a drawing.
With the same ease the Hatching-engine can revert to filling it solid for the time being.
Or at least warn the user, once on loading is enough.
Like warning that there is 3D data in a drawing, except for QCAD/CAM.
The required Hatch for this test and the next one has a density of only 1 segment per mm at unit scale.
The Add-On deliberately uses the hatching engine to fill an entire area.
In scale 0.08 that are 12.5 parallel segments per mm, quite harsh but still feasible if you max out the 'Timing-out' preference.
HJ Seef requirements for this tool are near the limit of what is possible based on his 'White paper'.
Both tests produce over 10k segments in an Hatched area not larger than 78 by 124mm.
Zig-Zag pocketing for reasonable tool diameters is thereby implemented.
A larger Laser spot would be a good idea in his case.
Regards,
CVH