Show realistic light and shadows sample

[darryl-lynch]

Description

Add realistic light and shadows sample

Links and Data

Issue: https://devtopia.esri.com/runtime/kotlin/issues/5316
vTest: https://runtime-kotlin.esri.com/view/all/job/vtest/job/sampleviewer/86/

What To Review

• Review the code to make sure it is easy to follow like other samples on Android
• README.md and README.metadata.json files
• First time using SceneView, so please ensure usage is correct
• Screenshot is not done yet as UI may change

How to Test

Run the sample on the sample viewer or the repo.

[colinanderson]

@darryl-lynch a few comments to look over

[colinanderson]

I think using now() here creates a bug because you are applying the slider time seconds to the current time.

I noticed this because running the sample I see shadows when the slider is all the way to PM when I'd assume night time and also shadows when the slider is all the way to AM again assuming it would be night.

[darryl-lynch]

I think this is a timezone issue, since the scene jumps to Portland in PST but now() is being calculated relative to UTC. So the time on the slider and the time of the sun will be 8 hours off. I've updated the logic to use PST and set a default time of 15:00.

[darryl-lynch]

Actually I feel like the way I've set the default time is probably breaking some kind of compose rule

edit: I think I've fixed that as well now

[colinanderson]

I think it would be good to give the slider tick marks every four hours like the design.

Ideally we'd make it look more like the design but looking at the slider doc it looks like the Compose slider isn't that customisable.

[darryl-lynch]

I looked into it and it seems like it might be possible but it would require creating a whole new component for it. Swift doesn't have the labels so there is at least precedent for not having the ticks.

[colinanderson]

@darryl-lynch I think you can simplify things if you take a look at all the https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/time/OffsetDateTime.html and related methods.

[colinanderson]

@darryl-lynch I think ideally the model would just know the current time and the slider would call setSunTime which would update the model's time. You are sort of doing that but in an awkward way of recalculating from a midnight start time. If 3pm is the start time we want to use then the calculations should flow from that and the slider range could reflect that (see comment on -ve to +ve range).

I was expecting that setSunTime would just be something like

currentTime = currentTime.plusSeconds(seconds)

but that seems to introduce flickering.

[colinanderson]

This local date time appears twice in the code (here and line 95) but would be better if it was just a constant or some other fix.

You should be able to do something like

    val initialDateTime = LocalDateTime.parse("2000-09-22T00:00:00").atZone(ZoneId.of("US/Pacific"))

    /**
     * Update the sun time of the lighting options state used by the scene view.
     * Uses the range 0 seconds (12 am) to 86,340 seconds (11:59 pm).
     */
    fun setSunTime(sunTime: Int) {
        lightingOptionsState.sunTime.value = initialDateTime.plusSeconds(sunTime.toLong()).toInstant()
    }

[colinanderson]

Could the range not be from -ve to +ve and then you can just do plusSeconds against a known 3pm time?

[colinanderson]

@darryl-lynch looks like what we discussed earlier 👍

[TADraeseke]

I'm happy to take 2nd review on this one @darryl-lynch