Got the question if pekwm supported HiDPI display, or theme scaling more specifically, and as it did not I got excited about it and started implementing theme scaling for pekwm and its shipped tools.

A single scaling setting in the Screen section controls the scaling:

Screen {
    Scale = "2.0"
}

If the factor is an integer, pixels are scaled to 4, 9, 16 etc pixels without any scaling artifacts. It is possible to specify 1.5 but scaling result will not be as clean.

An example of what it looks like, using scale 2.0 on a standard DPI monitor together with bitmap fonts in the terminal:

What is scaled

• Values specified in pixels are multiplied with the factor when loaded from the configuration.
• Images are scaled at load time.
• Cairo fonts size is multiplied with the factor.
• Xft fonts is NOT multiplied with the factor, they adjust with DPI setting of your display.
• Bitmap fonts are rendered as is and then scaled (this is an area with much room for improvement performance wise)

Extras

In additions to just scaling the values on load, there is a new atom set on the root window _PEKWM_THEME_SCALE that is updated whenever the scale is changed causing pekwm_panel and pekwm_dialog to reload the theme and resize itself for the new scale.

Demo