0 is not of type DOUBLE-FLOAT in make-level-bar about cl-gtk4 HOT 4 CLOSED

In Common Lisp, single-precision floating-point is the default, so both 0.0 and 0s0 represent single-precision floating-point numbers. To use double-precision floating-point, you need to write it as 0d0. Therefore, your code should be modified as follows:

(let ((level-bar-widget (gtk:make-level-bar :min-value 0d0 :max-value 4d0)))
  (setf (gtk:level-bar-mode level-bar-widget) gtk:+level-bar-mode-discrete+)
  (setf (gtk:level-bar-value level-bar-widget) 2d0)
  (gtk:box-append box level-bar-widget))

from cl-gtk4.

Aha, so maybe I'm doing this wrong but what if the data in the code is an integer? I'm trying to draw the HP a unit has remaining and I had thought that a discrete-mode level-bar from 0 to unit/max-hp, with the value set to unit/current-hp would be the best way to do that. But you can't lose half a hitpoint, so I'm keeping it internally as an int.

Is there another widget that would be better for this? I had originally considered making a drawing-area and drawing filled and emptied circles to mark of hits, but then I found the level bar.

from cl-gtk4.

I went ahead and just used either 0d0 or (float (num/accessor obj) 0d0) and it is working. So I'll just run with that for now since looking through the widget gallery didn't give me any more inspiration.

from cl-gtk4.

Many functions in GTK accept double-precision floating-point numbers as parameters. You can also use (coerce 123 'double-float) to achieve the same effect. You don't have to worry about the range of values because double-precision floating-point numbers can represent a much larger range than the commonly used int in C or Java.

from cl-gtk4.