More clear documentation in preset array usermod

usermods/preset_array/readme.md

@@ -1,5 +1,5 @@
 # Preset Array usermod
-This usermod lets you navigate a large number of effect presets more easily. You can group effects together however you see fit into *banks* that you can navigate either between (eg bank 1 to bank 2) or within (switch between presets inside a bank). It's particularly handy for non-touchscreen interfaces, like pushbuttons or encoders.
+This usermod lets you navigate a large number of effect presets more easily. You can group effects together however you see fit into *banks* that you can navigate either between (eg bank 1 to bank 2, up and down in the image below) or within (switch between presets inside a bank, left and right in the image below). It's particularly handy for non-touchscreen interfaces, like pushbuttons or encoders.
 
 ![A graphic showing three boxes. The first contains 3 sets of LED strips of different hues but the same effect, labeled Bank 1. The next box shows only 2 LED strips with rainbow themes, and is labeled Bank 2. The final box shows 4 LED strips and a representation of different LED chase effects, labeled Bank 3.](PresetArrayDiagram.svg)
 
@@ -22,30 +22,40 @@ This is assuming you've defined presets for given effects with the ID numbers 10
 ## How it functions
 After starting up WLED in this example, the state will be Preset 10---you will want to set this preset to be applied at boot when creating it. One option is to cycle through banks. Cycling up will apply Preset 20, and if cycling up again, Preset 30. If a wrapping command is used, then cycling up a third time will cycle back to Preset 10. From Preset 10, the other option is to cycle within a bank. Cycling up will apply Preset 11 next. Cycling down with a preset wrapping command from 10 will apply Preset 12.
 
+Be sure to check the "enabled" box to turn the preset on.
 
 ## API commands
-The commands are sent at the top level of the [JSON state API](https://kno.wled.ge/interfaces/json-api/), under the key `"pa"` for Preset Array. Here are some of the possible commands, the same pattern applies for both banks and presets.
+The commands are sent at the top level of the [JSON state API](https://kno.wled.ge/interfaces/json-api/), under the key `"pa"` for Preset Array. Here are the supported commands:
 
 | Command | Result                            |
 |---------|-----------------------------------|
 | `b~`    | Increment bank with wrap around   |
-| `b+`    | Increment bank without wrapping   |
+| `b~-`   | Decrement bank with wrap around   |
+| `p~`    | Increment preset with wrap around |
 | `p~-`   | Decrement preset with wrap around |
-| `p-`    | Decrement preset without wrapping |
 
-Personally, for the navigation commands I'm interested in, I've defined some presets and then assigned their IDs to [buttons]. I name them with an underscore at the start so they are sorted separately. One such preset looks like this in the interface:
+Less broadly useful are the no-wrap variants of these commands, where in our example, incrementing the bank from Preset 30 would not go anywhere. I expect incrementing from Preset 30 to Preset 10 would be a more desirable functionality.
+
+| Command | Result                            |
+|---------|-----------------------------------|
+| `b+`    | Increment bank without wrapping   |
+| `b-`    | Decrement bank without wrapping   |
+| `p+`    | Increment preset without wrapping |
+| `p-`    | Decrement prese  without wrapping |
+
+Personally, for the navigation commands I'm interested in, I've defined some presets that send these commands and then assigned their IDs to [pushbuttons](https://kno.wled.ge/features/macros/#buttons). I name the presets with an underscore at the start so they are sorted separately from the effects presets. One of them looks like this in the presets interface:
 
 ![A screenshot showing a preset with name "\_bank_up" and API command {"pa" : "b~"}](ScreenshotBankUp.png)
 
 ## Maximum number of presets, banks
 By default, you can store up to 64 presets in up to 23 banks. These numbers can be increased if you have the memory for it, by redefining `USERMOD_PRESET_ARRAY_MAX_PRESETS` and `USERMOD_PRESET_ARRAY_MAX_BANKS` respectively.
 
 ## Other considerations
-This usermod naively keeps track of the current position in the array. If you use the navigation commands to get to Preset 20 in our example above, and then use the web interface to apply Preset 10, sending an Cycle Bank Up command will still go to Preset 30 as if the previous state was still 20.
+This usermod naively keeps track of the current position in the array. If you use the navigation commands to get to Preset 20 in our example above, and then use the web interface to apply Preset 10, sending an 'Increment bank with wrap around' command will still go to Preset 30 as if the previous state was still 20.
 
 I like to save presets with "include brightness" unchecked, so that changing the brightness is independent to the changing of effects. In fact, on my own WLED builds I change the default of that checkbox to unchecked, by editing the file `wled00/data/index.js` and rebuilding the web interface with npm before compiling.
 
 ## Advanced ideas
-A preset in the array can be applying effects to multiple LED segments.
+A preset in the array can be applying different effects to multiple LED segments, as a preset can make an arbitrary API call.
 
-A separate default applied preset can make sense, which is a copy of the first preset in the array *except with a brightness included*. I set this to a sane initial brightness and have buttons to separately control brightness.
+A separate default applied preset can be a useful tool, created as a copy of the first preset in the array *except with a brightness included.* I set it to a reasonable initial brightness and have buttons to separately control brightness.