bug#21415: 25.0.50; Emacs Trunk -- pixelwise width/height for x-create-frame

[martin rudalics]

> I am trying to do three things:
>
> (1) efficiently create a new frame that is exact as to pixelwise
> width/height so that `(set-frame-size FRAME WIDTH PIXELWISE)` is not
> needed after each new frame is created;

Interesting.  This is the first time someone asks for this.  Do you have
a particular use case?

> (2) pass a pixelwise argument to `x-create-frame` that would resolve
> the first goal [?];

We'd need a ‘pixel-width’ and a ‘pixel-height’ frame parameter.  When
any of these is present, it would be used instead of the ‘width’ and
‘height’ parameters.  Alternatively, we could interpret floating point
values of ‘width’ and ‘height’ specially.

> (3) avoid intermittent visual flickering of the entire frame that is
> caused by a frame creation at the default size of `(width . 80)
> (height . 35)` followed immediately by programmatically enlarging the
> frame substantially with `set-frame-size` using the pixelwise
> argument.  [The intermittent visual flickering can be avoided by
> setting the `mode-line-format` to `nil`; however, the default
> `mode-line-format` causes/contributes to the visual flickering.]
> [This did not happen with the Emacs Trunk from last year, but happens
> now intermittently with a current version.]

Could you try bisecting to find out when this started?

martin