Support for hit detection in styles with custom rendering

[ashchurova]

This fix is for Issue 8136. As per @ahocevar request defined new optional property for ol.style.Style type called hitDetectionRenderer and it is used if specified. If it is not specified logic in CanvasBuilder.drawCustom falls back to passed renderer. This is my first time contributing so I am new to the process. @ahocevar you did mention in your comments that you wanted use hitDetectionRenderer when no custom renderer is specified. Still researching how to do that. Because that would mean recoupling drawing from hit detection instructions.

[ahocevar]

Good work! As far as I can tell, this is exactly what I had in mind. Maybe add a test and an example, then this should be good.

[ashchurova]

@ahocevar OK :) Sorry for the delayed response, had a long labor day weekend. So I will add tests and and example to your samples library. I need to think about what would be a good case to have different renderer for hit detection.

[ashchurova]

@ahocevar Hi Andreas, I am having trouble starting serve-examples while working on the example. When I run npm run serve-examples I get an error:

[webpack-cli] Failed to load 'C:\Dev\openlayers_my_fork\examples\webpack\config.mjs' config
[webpack-cli] Error: Not supported

Any suggestion on how to fix this one?

[ashchurova]

@ahocevar Hi Andrea, added a sample for custom hit renderer, I kind of based it on the existing custom renderer sample for circle and showed that only label is used for hit detection. Let me know what you think. Thanks.

[MoonE]

Thanks for working on this neat feature, @ashchurova.

[ashchurova]

@ahocevar Hi Andreas, no sure why these unit tests are failing on the server. All unit tests pass on my machine. Could it be that there is a race condition some sort? Thank you.

[ashchurova]

@ahocevar Hi Andreas, no sure why these unit tests are failing on the server. All unit tests pass on my machine. Could it be that there is a race condition some sort? Thank you.

Now Browser tests ran passed, interesting.. @MoonE I have addressed all your requested changes.

[ashchurova]

@ahocevar any update on when this PR will be merged or any other feedback? Thanks.

[ahocevar]

Hey @ashchurova, sorry this is taking so long. Unfortunately I have been too busy with my day job and FOSS4G preparation. I'll be looking into it as soon as possible.

[ahocevar]

Excellent work, @ashchurova! Thanks a lot for this contribution, and thanks for adding an example that shows custom style renderers in action.

[ahocevar]

@MoonE, I think all your comments were properly addressed, but please double-check and approve when you're happy too.

[MoonE]

The requested changes are good, thanks @ashchurova.

[ashchurova]

@ahocevar @MoonE Yeay!! When do you plan to publish this change? Thank you.

[ahocevar]

@ashchurova It is already published on the dev tag. npm install ol@dev will pull that for you. It will of course be in the next release. We published v6.8 a week ago, and we publish releases approximately every 2 months.