Hi Everyone, The Melbourne ADUG July meeting is on Monday Night, 21st July at 6:00pm AEST.
This month Roger Connell will discuss his solution to handling an indeterminate
number of images on a form and in the process touch on video capture and
presentation.
There are two demonstration applications
The original FMX Implementation for Windows and Android and VCL
implementation to enable access to Linux via Lazarus.
These project and the libraries within hopefully provide a basis for a
discussion on the flexibility of Delphi and has the potential to share
code which may be of use to others.
Meeting opens at 6:00pm for a 6:15(ish) start.
Meeting will be on Zoom and live at the Melbourne Mens shed.
Zoom links here shortly before the meeting starts.
At Monday night’s meeting David Berneda gave a brief outline of the recently open sourced TeeBI library.
It seems to be a very high performance in memory component for importing
potentially very large sets of data from user data sources, and then working with them
with ability to rapidly query this imported data.
And then charting this data.
Thank You David.
Roger Connell then gave a presentation on some Image handling with both FMX for android/windows and VCL for linux/lazarus.
This was quite interesting, he had a bunch of images shown on a Panel,
where it would resize and move the images to fit to the panel. More
images could be added while running. (presumably also could be removed)
Some of these images were simple fixed images, while others were
connected to a camera on phones (via a tcp/ip stream), and others
were connected to a virtual camera device. (Providing a simple moving
image)
With functionality to blank the connected camera images if the camera
becomes disconnected.
He has a bunch of utility libraries (source) which are compiled in as
part of the build. Where only the used functionality is linked in
because of the smart linker.
I have sworn at this behaviour before, where in debug you attempt to call a method that is right there in the source, but you just get back an error indicating the method was removed by linker.
But really much better that than just leaving all that extraneous code in there. I have also at times worried about including large utility source files, thinking should I just extract the bits I need??
He has also built his own ansistring type for use with the NextGen
compilers which were used for mobile development until quite recently.
(And don’t have an ansistring type)
Perhaps more as an array of bytes, that you can put (some) characters
into, and append strings, etc. But also do string type operations with,
and not get messed by unicode conversions.
Sue mentioned she uses the RawByteString type for this sort of thing.
So much pre-Unicode Delphi used strings as byte arrays and pchar’s pointing at them. Which broke post Unicode.
There was also a note in these forums from Vincent recently about the
Spring4D TBuffer type, that indicated it could be good for this type of
thing.
Roger also talked about a few other ways he goes about and does things,
and some of the issues he has encountered while doing mobile development
these are also mentioned in the PDF referenced above.
Thanks Roger
Hopefully there may be a presentation on the Image Distribution over
TCP/IP (from the phones) at some stage.