I have a VERY large drawing - the original DWG is 5Mb, and the DXF as it saves with no changes is approximately 12.5 Mb and about 4500 elements. A large percentage of the elements appear to be splines. It’s actually a detailed exterior drawing from Ford of a Ford Transit van, including sections, roof plans, and front/rear/side elevations.
I tried splitting out part of it (just the roof plan), but the performance is still horrible. As an example, unlocking a layer containing most of the drawing takes between 30 and 40 seconds! The roof plan alone is about 1400 elements; many of them are splines. I did go through and remove the unused blocks (many!) and layers, with no noticeable change in speed.
System is OpenSUSE Linux 64-bit with all current patches running on a quad-core i5-6500 3.2Ghz with 64Gb of physical memory. I’m running QCad Pro 3.25.2. During the long delays, it appears that qcad-bin is using 100% of ONE core (ie, 25% of my available CPU cycles) and between 6% and 10% of the available memory. Swap usage is 0.
I’d be happy to post the roof plan portion if it’s not too large - about 4.5Mb.
Any suggestions about how I might improve the speed of typical tasks while working with this drawing???
A dwg with 4500 items making up 5Mb intrigues me/us…
‘elevations’ make us wonder if there are non-zero Z values.
‘30 - 40 seconds!’ to unlock a layer with about 4500 items is not considered normal.
Question: In Model_Space?
Question: Does QCAD report unsupported items when loading the file?
Question: What kind of splines?
2 types are QCAD native, I am aware of a third type supported.
Type 3 are in fact chains of Bézier Curves.
Unused Blocks, nor empty Layers contribute much to delay. A vast amount of items do.
The Block/Layer structure itself can make it troublesome to render.
Mouse actions can be slow with big files, keyboard can be quicker.
E.g. zooming with [+] & [-]
OK, the extracted roof plan is attached. The splines all show up as “Spline [1]” in the property editor. I also ran Misc → Modify → Flatten Drawing to 2D, but (once again , no noticeable performance change.
Model_Space: Yes
Errors or unsupported types while loading: No
For my own purposes, the outlines here have been split into two layers, but they were all on one layer in the original drawing.
OK the file loads slow and there is a ‘medium’ lagging.
But it seems I have less problems with that still using 32bit.
A quick review showed that some/many/all splines use a specific LineType ISO dash. (872 as is)
QCAD has to render all the dashes …
In CAD it is usually the layer that defines the properties apart that exceptions could use a specific property.
Viewing all:
1408 exceptions on LineType.
1108 exceptions on LineWeight.
232 exceptions on Color.
On top: Layer ‘vehicle_roof_background’ uses dashes too.
Once I altered all to by Layer and set all layers to continuous the performance went up considerable.
Now it depends largely on how much I see from the drawing.
Up close the mouse works fine.
Not up close the keyboard is a better option.
About 800 Splines do use degree 5 and in some cases it is even obvious they don’t display correct.
Changed all to degree 3
How did you identify and change the spline “type” - I don’t see that in the manual (or the UI ) Or is that the “Degree” setting in the Property editor?
But by this the drawing is no longer the same at some places.
While at others places it made more than sence to do so.
Still there are fuzzy splines, look close now you can navigate better.
, no noticeable performance change.
