Re: [Mlterm-dev-en] feature request: coloured transparency

[MINAMI H. <mi...@mi...>]

On Tue, Mar 01, 2005 at 04:10:53PM +0100, Christian Zoz wrote:
> Hi mlterm developer,
> 
> before i changed to mlterm i was using wterm. And i loved one feature
> of wterm very much: It was able to set the beckground to shaded
> transparency which was colored at the same time. I used different
> colours for different user/machine but could see the desktop picture
> shine through.
> wterm -bg blue -sh -tr
> 
> Is it possible to add such a feature to mlterm as well?

There are several possible implemantation of translucent color
background and each of thme have pros and cons.

- dumb method
  1) get root pixmap
  2) do color-blending
  3) set the result as a mlterm's background

  pro: any color can be specified for blending
  con: color-blending can be very very slow

- aterm's hack
  1) get root pixmap
  2) copy only part of color plane ( ex. copy only blue)
  3) set  the result as a mlterm's background
  
  pro: color-plane limited copy can be done on X server and be very fast.
  con: the color to specify must be one of R/G/B plus green/yellow/magenta

- use recent extensions for X
  1) set the background of mlterm's widnow to be half transparent.
  2) recuest xcompmger to do the right thing

  pro: it may be hardwere accererated and quite fast.
  con: require xrender / xcompose / xfix.

I'll consider to support one of them in mlterm 3.x.

For mlterm 2.9.x, you can set translucent image as a background.
i.e. if you set 1x1 blue half-transparent image(attached) as
 mlterm -p 1x1_blue.png

Note that the feature was implemented only to take fancy screenshots and 
not meant to be used for serious task. it makes window resizing sluggish
and non't update window background when the window is moved.

minami