Pausing before starting sunlight looks odd

[KatieWoe]

Test device
Samsung
Operating System
Win 11
Browser
Chrome
Problem description
For phetsims/qa#871
You can pause the sim before starting sunlight. When you start the sunlight it makes the starting up sound and slowly brightens, but nothing else happens. This isn't necessarily wrong, but it does look very odd. It may be worth taking a second look at this use case
Steps to reproduce

1. Pause the sim in the time control area
2. Press Start Sunlight

Visuals

Troubleshooting information:

!!!!! DO NOT EDIT !!!!!
Name: ‪Greenhouse Effect‬
URL: https://phet-dev.colorado.edu/html/greenhouse-effect/1.1.0-rc.1/phet/greenhouse-effect_all_phet.html
Version: 1.1.0-rc.1 2022-12-23 00:15:29 UTC
Features missing: applicationcache, applicationcache, touch
Flags: pixelRatioScaling
User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36
Language: en-US
Window: 1536x714
Pixel Ratio: 1.25/1
WebGL: WebGL 1.0 (OpenGL ES 2.0 Chromium)
GLSL: WebGL GLSL ES 1.0 (OpenGL ES GLSL ES 1.0 Chromium)
Vendor: WebKit (WebKit WebGL)
Vertex: attribs: 16 varying: 30 uniform: 4096
Texture: size: 16384 imageUnits: 16 (vertex: 16, combined: 32)
Max viewport: 32767x32767
OES_texture_float: true
Dependencies JSON: {}

[marlitas]

Also strange that you can pause and still press the step forward button before the sunlight starts, but nothing happens.

[jbphet]

@arouinfar - Here is one suggestion on how to address this: Disable the pause functionality when the sunlight hasn't been started.

You may have other thoughts. Assigning to you for evaluation.

[arouinfar]

Thanks @KatieWoe @marlitas.

Here is one suggestion on how to address this: Disable the pause functionality when the sunlight hasn't been started.

@jbphet that seems like a reasonable change to make, but we should evaluate how this would interact with description. We already have a variety of context responses that inform users of the possible interactions between Start Sunlight and the PlayPauseButton. For example:

• Sunlight started, sim paused. (Pressing Start Sunglight when sim is paused.)
• Sim paused, sunlight not started. (Pressing pause when sunlight hasn't started.)
• Turn on sunlight to play sim. (Pressing play when sunlight hasn't started.)

I am fine leaving this as-is for the prototype and addressing in the next release, but I'll leave it up to @jbphet.

[samreid]

@jbphet and I reviewed this behavior, and we both recommend that we wire up the enabled property of the play/pause/step buttons to whether the sunlight is showing. We believe this will be a better user experience, and should not be difficult to implement. We will create a side issue about updating the description accordingly.

[Nancy-Salpepi]

In rc.2, the play/pause/step buttons are disabled until the Start Sunlight button is pressed. Closing.