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Writing a BPF-like editor with ruler between 0 and 1

OpenMusic
#1

Hi,

I am writing an OM library that requires a BPF-like editor class, but with a vertical ruler ranging from 0 to 1. Following the BPF I set the range like this:

(defmethod init-coor-system ((self my-panel))  
  (set-ranges self '(0 10) '(0 1))  
  (redraw-rulers self)  
  (om-invalidate-view self))

This doesn’t give me any steps on the ruler between 0 and 1, however (see the attached screenshot). From other OM editors (like the Maquette) I know that it’s possible to achieve this, but I’m obviously missing some setting. I tried defining the ruler like this:

(om-make-view 'ruler   
              :axe 'y  
              :zoom 1000  
              :minzoom 0.001  
              :assoc-view panel  
              :position (om-make-point 0 0)  
              :size (om-make-point 25 (- (h self) 25)))

But that doesn’t give me what I want either. I’ve dug deep into the code, but can’t seem to figure this one out. Any pointers would be greatly appreciated.

Many thanks,
Chris

editor.png

#2

Hi Chris

BPF editors in OM (and BPF objects in general) internally deal only with integer values.
This means that when a BPF has 2 decimals precision and ranges from 0 to 1, it “internally” ranges from 0 to 100.

If the “real” (internal) range is [0 1] then there is no step in between.

So I think what you should do is set the ruler ranges according to your decimals precision (0 10^decimals)

I hope this helps,

Jean

#3

Ah, I understand now. My mental picture of how the BPF works internally was incorrect. Thanks for your help Jean!

Best,
Chris