> 
> Ideally, what I'd love to have is a mode that implements a grid-like layout, where each character occupies an exact multiple of the base character width, regardless of which font it comes from.
> 
> Deciding what this multiple should be for each character could be done in various ways; for my purposes (and for OP's case as well, I think), it would be enough to use one cell for halfwidth characters, two for fullwidth characters, and add a few exceptions for things like TAB and zero-width spaces (I'm using the terms fullwidth and halfwidth in the sense of https://www.unicode.org/reports/tr11/ <https://www.unicode.org/reports/tr11/>).
> 

Clément expressed the idea better than I could have. However, I’d like to see it as a face attribute instead of a mode. (Because I want to align my org table). Maybe there could be a face attribute (:grid WIDTH) that instructs the display engine to pad each glyph to have width that is a multiple of WIDTH in pixel, and if WIDTH is t, default to “base character width”?

I remembered that ‘window-width’ gives width in char widths and had a look at its source. It knows the character width from FRAME_COLUMN_WIDTH; the comment says the value currently equals to the average width of the default font of the frame. I think this value can be used as the “base character width”.

Yuan