Can the Heat Metal spell target a set of Dragon Scale Mail made from metallic dragon scales?

The heat metal spell can target "a manufactured metal object", including "a suit of heavy or medium metal armor".

A suit of Dragon Scale Mail is clearly a manufactured object, but if it’s made from metallic dragon scales, is it metal, and thus a valid target? Are bronze dragon scales actually made of bronze, or are they just colored like that?

I’m just assuming chromatic dragon scales are inarguably organic.

Finding the smallest number that scales a set of irrational numbers to integers

Say we have a set $ S$ of $ n$ irrational numbers $ \left\{a_1, …, a_n\right\}$ .

Are there any known algorithms that can determine a scaling factor $ s \in \mathcal{R}$ such that $ s * a_i \in \mathcal{N} \;\forall a_i \in S$ , assuming that such factor exists? If multiple exist, how about the smallest one?

Moreover, I wonder, under what input conditions could one assume that an algorithm for this problem can’t (or can) return a valid scaling factor?

If no known algorithms to this problem exist, are there any known classes of “scaling algorithms” that may solve a similar problems?

Defining colour themes of gradient scales: should I use hex or RGBA?

I’m relatively new to CSS. I’m trying to figure out why my UX team sometimes defines colours with hex codes and sometimes uses RGBA.

Context: We build highly technical, management web apps. All of our web apps have a white background and don’t tend to layer elements (e.g., not marketing images as backdrops). Some of the designers feel RGBA helps control colour contrast ratios. Some designers just prefer using RGBA over hex. Some designers use hex. No one has given me a clear reason for their choice. I’d like to know the pros and cons of each technique and in which situations one method is better than the other because I’m building a colour theming solution for our core framework. We want gradient scales for each of our primary and secondary colours. There’s no current requirement for transparency, but I suppose one day there could be.

I came across a related UX SE post: Why isn't primary text full opacity? Answers talk about RGBA helping to enforce standard use of colour. That is, if you start with an RGB colour and use the alpha value to adjust light/dark, you could ensure a consistent colour gradient scale. (Note: That post has a good image showing a colour scale using hex and then the equivalent alpha value beside it:

But then what happens when you have HTML elements overlapping and you don’t want to them to appear partially transparent and yet want to use the appropriate colour? Do you use an equivalent RGB with alpha 1 or a hex code?

As for the contrast ratio theory, here’s what one UX designer told me: RGBA color always maintains the same level of contrast from whatever it’s placed on. If you put an #AAA body text on an #FFF background, versus if you put it on a #EEE background, the #AAA text will look lighter on the #EEE background. But if you put rgba(0,0,0,0.33) on an #FFF vs #EEE background, the text will always have a 33% darker contrast on both. Is that true? Using a contrast ratio calculator ( rgba(0,0,0,0.33) on #FFF has a 2.3 ratio whereas rgba(0,0,0,0.33) on #EEE has a 2.26 ratio. Close, but not identical. #DDD goes down to 2.23.

Material UI Color Palettes seems to use hex codes (see ), but I’ve seen other writing to suggest at times Material UI uses RGBA sometimes. Not that Material UI is always right. 🙂

So again, I’m looking for the pros and cons of hex values vs. RGBA values and when it’s best to use which.

Different Scales for different 4K and FHD displays, in X11 and Wayland

I want to configure different scales for my 4K monitor and the FHD, but it looks an impossible challenge.

Next my different tests and conclusions. A lot of things are not working, so I need what to try to fix first. Could you advise me about which path to take to get it working?

One important note: 30Hz is not enough refresh ratio. After a few hours, my eyes are killing me.


  • BUG? Thunderbolt 3 cannot handle 4K higher than 30Hz.
  • BUG? HDMI is not working in Wayland. The monitor detects the connection but goes to sleep mode (No signal. Entering in power saving mode).
  • BUG? In X11 the Scale option is shared between all displays.
  • Fact: Display management is the worst parts of Linux.


  • SO -> Ubuntu 18.04.2 LTS
  • Drivers -> Nvidia 390.116
  • Laptop -> Dell G5 15
  • 4K -> LG27UD68P-B
  • FHD -> HP 2311x
  • Video -> GeForce GTX 1060 with Max-Q Design/PCIe/SSE2
  • Video lspci -> NVIDIA Corporation GP106M [GeForce GTX 1060 Mobile]
  • Thunderbolt 3 -> Intel Corporation JHL6340
  • Thunderbolt 3 to HDMI adapter ->

Test 1

  • X11
  • 1 shared Scale option
| Connector   | Display   | Resolution | Hz  | | ----------- | --------- | ---------- | --- | | Built-in    | Built-in  | 1920x1080  | 120 | | HDMI        | 4K        | 3840x2160  | 60  | | Thunderbolt | FHD       | 1920x1080  | 60  | 

Test 2

  • X11
  • 1 shared Scale option
| Connector   | Display   | Resolution | Hz  | | ----------- | --------- | ---------- | --- | | Built-in    | Built-in  | 1920x1080  | 120 | | HDMI        | FHD       | 1920x1080  | 60  | | Thunderbolt | 4K        | 3840x2160  | 30  | 

Test 3

  • Wayland
  • HDMI does not work
  • 2 shared Scale options
| Connector   | Display   | Resolution | Hz  | | ----------- | --------- | ---------- | --- | | Built-in    | Built-in  | 1920x1080  | 60  | | HDMI        | NO SIGNAL |            |     | | Thunderbolt | FHD       | 1920x1080  | 60  | 

Test 4

  • Wayland
  • HDMI does not work
  • 2 shared Scale options but 4K is not scaling 🙂
| Connector   | Display   | Resolution | Hz  | | ----------- | --------- | ---------- | --- | | Built-in    | Built-in  | 1920x1080  | 60  | | HDMI        | NO SIGNAL |            |     | | Thunderbolt | 4K        | 3840x2160  | 30  | 

Display only scales correctly when I boot via recovery mode

I’m running ubuntu 18.10, with i3 as my window manager. I switched to lightdm recently and my UI doesn’t scale correctly (screen is 1440×2560). I’ve tried most of the fixes I see online, like setting dpi manually with xrandr --dpi 192, which seems to make no difference; the entire UI is far too big.

However, if at boot time I select recovery mode, and then immediately select the “continue boot” option instead of actually using any of the recovery options, then the display scales normally.

Any idea why this might be? I’d like to be able to boot normally.

Are there standards for 5 star rating scales of photos?

I’m preparing to go through thousands of photos and organize them and part of that is to give each one a rating of 1 to 5 stars. This has me wondering, has anyone developed a set of recommended standards for what qualifies a photo as 5 stars, 4 stars, etc. I’m looking for something that will make rating the images less subjective and give me specific photographic qualities to look for to reduce the effect of rating skew.

As an example that I just made up now, something like this:

  • 5 stars – Photo has perfect or near perfect sharpness of the subject, subject composition is as intended, light levels are perfect.
  • 4 stars – Photo composition is good, but sharpness or light levels are a bit less than perfect. Post processing may correct flaws.
  • 3 stars – Sharpness or light levels are good, but photo composition is not as intended.
  • 2 stars – photo is too blurry or light levels are . Cannot be corrected
  • 1 stars – photo is very blurred and/or has poor light levels. Cannot be corrected.

Ideally this would help me later find photos that could be corrected with additional post processing or future technologies such as advanced blur correction. I realize I could also tag such images as slightly blurry. Maybe there is a tagging standard? When I searched for these things online all I could find is how to use a 5 star rating system in a specific piece of software or how to implement one on your website, etc.