Watch out for hypes in ICT

Hypes

 ICT has a rich history of hypes where people thought that this would be a panacea for all problems. These hypes lasted for some time like paradigms in Karl Popper's science philosophy. From the top of my head we had the following hypes in the past:

• relational / SQL databases (70's)
• structural design
• object oriented design (80's)
• component based development (90's)
• design patterns (1995)
• scrum / agile (2001)
• AI (2022)

 All these hypes (except scrum) were useful but not to the extend of solving all problems. They are now part of the current solution domain. We also know now that these are still problems to tackle. Let's see what AI will bring us in the future. For now it's on the level of coding assist but not on the level of designing whole systems. In that part it still cannot replace programmers (besides that it makes mistakes).

Careful with AI tooling

AI tooling

 Since some period I started working with AI tooling. Mostly I use Gemini and Copilot inside Visual Studio. The experience is a bit of mixed feelings about this. Gemini had some good suggestions but failed also many times. Copilot has good code completion suggestions but misses the mark also. Copilot's function name suggestion are very welcome.

 On the other hand AI tooling is still full of mistakes. Some examples:

• I asked Gemini for camera sharpness algorithm. It came up with a good algorithm but the actual OpenCV function calls and parameters were incorrect.
• I asked Gemini to get the real sample time from an 'IMediaSample'. It suggest to use the non existing 'GetSampleTime'. There is b.t.w. a 'GetMediaTime' function but this returns the stream time; i.e. the time since the graph was running and not the time from the start of the video. 
• I asked Gemini lately of conversion from UCS-2 to UTF-16 and it wrongly suggested to use wstring_convert. However wstring_covert is hardbound to std::string as byte_string

 Even worse that sometimes AI tooling can suggest plain bugs. I was implementing a swap of width and height and Copilot's code complete came up with the following code snippet:

// NOTE: incorrect 

Size sz = ...;
if (sz.GetWidth() < sz.GetHeight())
{
   sz.SetWidth(sz.GetHeight());
   sz.SetHeight(sz.GetWidth());
}

This doesn't swap but sets the width and height on the old height value.

 AI tooling can be helpful but are still not on the level to be trusted blindly. They also now help with limited scope; e.g. code blocks; algorithms and functions. I am not aware if they can help in refactoring and extending architecture spanning solutions.

 

Debugging GDI drawing

GDI debugging

 The other day I had to debug a hard to track drawing bug. The application is built with the MFC framework so it still uses GDI on places to draw custom controls.

 The incorrect drawing artifact was displayed after an invocation of 'DrawText' with the flag 'DT_CALCRECT'. This was unexpected since with the flag the function doesn't draw and only measures the size. Eventually I realized that GDI batches invocations so perhaps the buggy overdrawing had already taken place before. What was needed to prove this hypothesis:

•  suppress GDI's caching mechanism through 'GdiSetBatchLimit'.
•  use direct drawing; so no memory device context

 With this in place indeed it could be seen that the mistake happened earlier in the code and that the 'DrawText' invocation was merely a flush of the GDI batch.

 Be aware that suppressing  GDI's batch might not always work. When the window where the drawing took place was on the primary monitor the batch mode could be turned off but on the second monitor it still cached its calls.