View Issue Details

IDProjectCategoryView StatusLast Update
0007788ardourbugspublic2020-04-19 20:18
Reporterjpcima Assigned Tox42  
PrioritynormalSeverityminorReproducibilityalways
Status closedResolutionfixed 
PlatformLinuxOSArch x86_64OS Versionunknown
Product Version5.12 
Summary0007788: Slider reacting strangely to LV2 property epp:rangeSteps
DescriptionWhen epp:rangeSteps is set on a control parameter, the slider in the generic UI reacts in stuttery manner, as if it resists to the mouse movement.

It was discovered while hosting a LV2 plugin built with faust2lv2.
https://www.youtube.com/watch?v=hKRucqEz-sA

The faust generator emits the epp:rangeSteps property for its controls.
Steps To ReproduceIt can be reproduced with a very simple faust program, such as the one attached
Build it with faust2lv2, and manipulate the slider in the generic UI to observe the problem.

The faust compiler was the version 2.15.11.
Tagslv2

Activities

jpcima

2019-08-17 15:44

reporter  

volume.dsp (94 bytes)   
process = *(gain) with {
    gain = hslider("[1] Gain [unit:dB]", 0.0, -60.0, +20.0, 1.0);
};
volume.dsp (94 bytes)   

jpcima

2019-08-17 15:56

reporter   ~0020725

attached: a LV2 manifest generated from the example faust file
volume.ttl (1,313 bytes)   
@prefix doap:  <http://usefulinc.com/ns/doap#> .
@prefix foaf:  <http://xmlns.com/foaf/0.1/> .
@prefix lv2:   <http://lv2plug.in/ns/lv2core#> .
@prefix ui:    <http://lv2plug.in/ns/extensions/ui#> .
@prefix epp:   <http://lv2plug.in/ns/ext/port-props#> .
@prefix atom:  <http://lv2plug.in/ns/ext/atom#> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs:  <http://www.w3.org/2000/01/rdf-schema#> .
@prefix units: <http://lv2plug.in/ns/extensions/units#> .
<https://faustlv2.bitbucket.io/volume>
       a lv2:Plugin ;
       doap:name "volume" ;
       lv2:binary <volume.so> ;
       lv2:optionalFeature epp:supportsStrictBounds ;
       lv2:optionalFeature lv2:hardRtCapable ;
    lv2:port [
	a lv2:InputPort ;
	a lv2:ControlPort ;
	lv2:index 0 ;
	lv2:symbol "Gain_0" ;
	lv2:name "Gain" ;
        lv2:portProperty epp:hasStrictBounds ;
        epp:rangeSteps 80 ;
	lv2:default 0 ;
	lv2:minimum -60 ;
	lv2:maximum 20 ;
	units:unit [
            a            units:Unit ;
            units:name   "dB" ;
            units:symbol "dB" ;
            units:render "%f dB"
	] ;
    ] , [
	a lv2:InputPort ;
	a lv2:AudioPort ;
	lv2:index 1 ;
	lv2:symbol "in0" ;
	lv2:name "in0" ;
    ] , [
	a lv2:OutputPort ;
	a lv2:AudioPort ;
	lv2:index 2 ;
	lv2:symbol "out0" ;
	lv2:name "out0" ;
    ]
.
volume.ttl (1,313 bytes)   

x42

2019-08-17 15:58

administrator   ~0020726

Likely already fixed in ardour git since https://github.com/Ardour/ardour/commit/0e79253412af587eb6cd8f3f72b841f5517dd47c
Commits before and after are related 14517e13ecb16051 (range step rounding) and 9cf9833a93f5af0 (log-scale + spinboxes).

jpcima

2019-08-17 17:40

reporter   ~0020727

I confirm that Ardour 5.12 + the commit 0e79253 has fixed the problem. The slider movement is smooth.
The commit diff did not apply directly on 5.12 source, but was fine with minor editing.

x42

2019-08-17 17:47

administrator   ~0020728

Thanks for testing. marking as resolved

system

2020-04-19 20:18

developer   ~0023800

Issue has been closed automatically, by Trigger Close Plugin.
Feel free to re-open with additional information if you think the issue is not resolved.

Issue History

Date Modified Username Field Change
2019-08-17 15:44 jpcima New Issue
2019-08-17 15:44 jpcima Tag Attached: lv2
2019-08-17 15:44 jpcima File Added: volume.dsp
2019-08-17 15:56 jpcima File Added: volume.ttl
2019-08-17 15:56 jpcima Note Added: 0020725
2019-08-17 15:58 x42 Note Added: 0020726
2019-08-17 17:40 jpcima Note Added: 0020727
2019-08-17 17:47 x42 Assigned To => x42
2019-08-17 17:47 x42 Status new => resolved
2019-08-17 17:47 x42 Resolution open => fixed
2019-08-17 17:47 x42 Note Added: 0020728
2020-04-19 20:18 system Note Added: 0023800
2020-04-19 20:18 system Status resolved => closed