Lazarus on Raspberry Pi 4 IDE response speed problem

[Thaddy]

Here it is nice to see that switching Buttons is cool until you put an Image on the form. Then, switching components becomes unusable.

Video: https://www.youtube.com/watch?v=rUItOqTz96U&feature=youtu.be

The bad news is I can reproduce that now. The good news is that there is work being done to the performance of the OpenGL back-end for the videocore V1.
It has not yet reached the same level of optimizations of the videocore 1V but that is a matter of time.
If you are adventurous, you can follow the development and try the trunk version of the OpenGL back-end.
It is the overlapping images that cause the problem, if they are nicely separated there is no issue.
Eventually the videocore V1 back-end should be *much* faster based on specs.

Note (to be sure) you do not need to use opengl or opengles yourself: this is abstracted away in the  X renderer.

One note that worries me slightly: you write you are sharing code between 3 and 4? I would not do that. Compile for 3 and 4 separately.
The 3 does not use MESA drivers, but EGL on top of broadcom blobs for the X renderer, the 4 has proper MESA drivers, but are not fully optimized into the X renderer yet.

One way to test it is to compile the Opengles and OpenGL examples that come with FPC. (skip the glx examples: these do not work fat enough yet)
You will note that you get twice the framerate compared to RPi3, so it is the x-renderer that does not yet use all available speed.

[DidaJI]

So now I eliminate the problem with the speed of graphics in Lazarus, now I'm running about 10 times faster. A problem with poor color rendering of large fonts has also been resolved!

In config.txt, just comment "dtoverlay=vc4-fkms-v3d".

Now it goes all perfectly and faster than RPI3B+

@Thaddy, thank you very much for kicking with rendering graphics. That helped me.

Zdenek.

[BosseB]

I just looked in my config.txt on an RPi4B with 4GB RAM running the standard desktop.
Here is what I found at the very bottom:

Code: [Select]

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
dtoverlay=vc4-fkms-v3d
max_framebuffers=2

[all]
#dtoverlay=vc4-fkms-v3d

So do you mean that it should be disabled for all versions except pi4?
Or should I comment out the active line for my pi4 too?
And what are the ramifications? I.e. how can I see if I am suffering from this issue?

[DidaJI]

@BosseB

Take a simple test on this my video: https://www.youtube.com/watch?v=KBmExC-ICD8&feature=youtu.be

If you can switch between TImage components as slowly as I do on video, then you have the same problem as me.

The second test, put on the Form one Label with some text, set font to red and increase the font to >150. If all letters are not red, you have the same problem again: https://www.youtube.com/watch?v=TOAQdGOXvCo&feature=youtu.be

To disable it, you must also disable the parameter in the [PI4] section.

Zdenek.

[JurVO123]

Hi,

With the suggestions of DidaJI, I am running a data-acquisition system.
On RPI4 it runs OK, but the GUI freezes after an hour or so, while the same app works perfect on PI3B+ for weeks running.

Any other suggestions?

Regards Jur