Laggy interface on macOS

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BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Tue Feb 25, 2020 2:47 pm

andrew wrote:
Mon Feb 24, 2020 1:31 pm
BobRockefeller wrote:
Mon Feb 24, 2020 1:22 pm
Are there plans to upgrade the underlying rendering engine to solve this? More and more computers, and almost all Macs, have high-resolution displays and those computers are especially prevalent in CADD.
Unfortunately, we have to rely on underlying toolkits for the rendering. If you're not happy with the performance or rendering quality of QCAD, I'm happy to offer you a full refund.
The user interface itself (menus, tools, dialogs, and the like) hold up well with retina resolution enabled. It is only the drawing area that suffers. If I'm reading the QCAD documentation correctly, it uses QT5 for the interface and the canvas. And QT5 uses OpenGL. Apple has depreciated the use of OpenGL in favor of Metal and Macs are "stuck" at version 4.1 of OpenGL.

Do I understand that correctly?

If so, does that satisfactorily explain the poor retina drawing performance?

With the deprecation of OpenGL on Macs, the future of CAD on Mac will have to be Metal. Are there plans to find a way to migrate QCAD?
Bob
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Bob Rockefeller
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andrew
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Re: Laggy interface on macOS

Post by andrew » Wed Feb 26, 2020 10:17 am

BobRockefeller wrote:
Tue Feb 25, 2020 2:47 pm
And QT5 uses OpenGL. Apple has depreciated the use of OpenGL in favor of Metal and Macs are "stuck" at version 4.1 of OpenGL.
QCAD does not use OpenGL (with the exception of the QCAD/CAM 3D simulation widget). We aim to support a wide range of platforms including Windows installations with broken or no OpenGL support.
BobRockefeller wrote:
Tue Feb 25, 2020 2:47 pm
With the deprecation of OpenGL on Macs, the future of CAD on Mac will have to be Metal. Are there plans to find a way to migrate QCAD?
We will continue to use the 2D drawing API of Qt for the foreseeable future and not dive into platform specific technologies such as OpenGL, GL ES, DirectX, Metal, Vulkan, etc.

BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Wed Feb 26, 2020 1:30 pm

andrew wrote:
Wed Feb 26, 2020 10:17 am
We will continue to use the 2D drawing API of Qt for the foreseeable future and not dive into platform specific technologies such as OpenGL, GL ES, DirectX, Metal, Vulkan, etc.
So QT is the bottleneck but it is cross-platform. Fair enough.

I was under the impression that OpenGL was more widely available. But like most things Windows, it is a separate driver that must be installed. I was also under the impression that a CAD user on Windows might have, or be willing to install, an OpenGL driver for their graphics card.

This leads me to assume that high resolution displays on Windows machines also suffer with lag or lower resolution display.

QCAD-Pro is a very powerful application at a price far below any competition. I suppose I will put up with the lower resolution graphics for a while.
Bob
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Bob Rockefeller
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Re: Laggy interface on macOS

Post by CVH » Wed Feb 26, 2020 4:00 pm

Do you read our posts?
QCADpro 3.23.0.0 / win7pro 32 bit / 4GB / 1e generation i7 2.6Ghz / HDD GeForce GT 520
CVH wrote:
Thu Feb 20, 2020 2:15 pm
No lag what whatsoever with the file.
CVH
QCADpro 3.25.2.1 / win7pro 32 bit / 4GB / 1e generation i7 2.6Ghz / HDD GeForce GT 520

BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Wed Feb 26, 2020 4:07 pm

CVH wrote:
Wed Feb 26, 2020 4:00 pm
Do you read our posts?
QCADpro 3.23.0.0 / win7pro 32 bit / 4GB / 1e generation i7 2.6Ghz / HDD GeForce GT 520
CVH wrote:
Thu Feb 20, 2020 2:15 pm
No lag what whatsoever with the file.
CVH
I read that. I don't believe that hardware will drive the 5120 x 2880 screen resolution of the iMac Pro. QCAD is not laggy when Retina resolution is disabled. But very high resolution displays are becoming the norm, not the exception. TurboCAD nor MacDraft, as two examples, are not laggy in full Retina resolution. As Andrew has pointed out, it appears to be the QT 2D toolkit that is a fault.
Bob
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Bob Rockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Wed Mar 04, 2020 4:11 pm

Here's another one that is laggy even with Retina resolution switched off.

The lag may have started after I created two blocks (the pool and the hot tub) with solid hatches. But the lag did not go away when I deleted the hatches and the blocks.
Attachments
Pool Plan.dxf
(119.52 KiB) Downloaded 55 times
Bob
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Bob Rockefeller
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Re: Laggy interface on macOS

Post by Husky » Wed Mar 04, 2020 7:05 pm

BobRockefeller wrote:
Wed Mar 04, 2020 4:11 pm
But the lag did not go away when I deleted the hatches and the blocks.
The pool hatch still exist in the drawing ...
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BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Wed Mar 04, 2020 7:45 pm

Husky wrote:
Wed Mar 04, 2020 7:05 pm
BobRockefeller wrote:
Wed Mar 04, 2020 4:11 pm
But the lag did not go away when I deleted the hatches and the blocks.
The pool hatch still exist in the drawing ...
It was hiding from me! Deleting it fixed the lag. So hatches appear to be a bad idea in QCAD - don't use them, or suffer lag. :(
Bob
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Re: Laggy interface on macOS

Post by Husky » Wed Mar 04, 2020 8:17 pm

BobRockefeller wrote:
Wed Mar 04, 2020 7:45 pm
So hatches appear to be a bad idea in QCAD - don't use them, or suffer lag. :(
Well - use a hatch as intended and you don't suffer lag!

You used a hatch with a scale factor of 1. That means QCAD had to build a hatch in your case with 1,201,880 entities. Every application slows down when it has to deal with over 1 million entities. Just imagine that that has to be recalculated again and again and again.

If you use an appropriate rate for the scale factor like 30 the same hatch will be built with 1366 entities. And QCAD will behave as fast as always.

Husky-2020.03.04-01.png
Scale factor 30
Husky-2020.03.04-01.png (22.35 KiB) Viewed 1024 times
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BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Wed Mar 04, 2020 8:39 pm

Husky wrote:
Wed Mar 04, 2020 8:17 pm
BobRockefeller wrote:
Wed Mar 04, 2020 7:45 pm
So hatches appear to be a bad idea in QCAD - don't use them, or suffer lag. :(
Well - use a hatch as intended and you don't suffer lag!

You used a hatch with a scale factor of 1. That means QCAD had to build a hatch in your case with 1,201,880 entities. Every application slows down when it has to deal with over 1 million entities. Just imagine that that has to be recalculated again and again and again.

If you use an appropriate rate for the scale factor like 30 the same hatch will be built with 1366 entities. And QCAD will behave as fast as always.
There's the trick! I thought a scale factor of 1 was the "safe" choice to minimize calculations. Thanks for the tip!
Bob
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Bob Rockefeller
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Re: Laggy interface on macOS

Post by CVH » Thu Mar 05, 2020 1:15 am

Some things that went wrong:
BobRockefeller wrote:
Wed Mar 04, 2020 4:11 pm
The lag may have started after I created two blocks (the pool and the hot tub) with solid hatches.
You did not use 'SOLID' to hatch but you used the 'SQUIGGLE-01' pattern.
BobRockefeller wrote:
Wed Mar 04, 2020 8:39 pm
I thought a scale factor of 1 was the "safe" choice to minimize calculations.
It is not a matter of a "safe" choise but of proper use.

'SQUIGGLE-01' in inch is an example of a 'Unit Tile' hatch pattern, 100% spaced.
The Tile is 1x1 inch and holds 28 line segment definitions.
At scale x1 every squared inch is hatched with these 28 line segments.
The pool has a surface of about 67,000 squared inch.
So, scale 1x is not that of a "good" choise.

As it is a hatch pattern with a semi fluent look, I can not call it a complex hatch.
Not because it isn't build up out of several hundreds of segments.
And not meaning that it don't uses certain angles that make it complex to render.
John Hyslop has coded it so that it is pretty stable at huge spans.

But it is true that:
Complex hatches induce a lag or fail altogether.
Huge hatched surfaces induce lag.
And that goes for 'micro' hatches too.
Redering hatches is obviously done different depending the used package.

That there is a flaw in the way Qcad is rendering hatches looks evident at some points.
A flaw, a shortcoming, a limitation.
It is quite hard to put your finger on when and what.
In 4 months I gathered many cases ...
... and as many counter indications.


In general there is still the advice to put hatches on a separate layer.
Apart from a short or the experienced long lag they tend to sit in front of other items.
Hiding the layers with hatches solves both.

Regards,
CVH
QCADpro 3.25.2.1 / win7pro 32 bit / 4GB / 1e generation i7 2.6Ghz / HDD GeForce GT 520

BobRockefeller
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Re: Laggy interface on macOS

Post by BobRockefeller » Thu Mar 05, 2020 1:50 am

CVH wrote:
Thu Mar 05, 2020 1:15 am

In general there is still the advice to put hatches on a separate layer.
Apart from a short or the experienced long lag they tend to sit in front of other items.
Hiding the layers with hatches solves both.
Another helpful tip that I will keep in mind.
Bob
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Bob Rockefeller
Midway, GA, USA

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