0001770: Specifying custom Zxx macro configurations to do High pass filter (f0f002xx) cuts at random filter frequencies - OpenMPT Issue Tracker

ID	Project	Category	View Status	Date Submitted	Last Update

0001770	OpenMPT	libopenmpt	public	2024-04-02 21:37	2024-04-02 21:53

Reporter	Yalek0391	Assigned To
Priority	normal	Severity	minor	Reproducibility	always
Status	closed	Resolution	no change required
Platform	x64	OS	Windows	OS Version	11

Summary	0001770: Specifying custom Zxx macro configurations to do High pass filter (f0f002xx) cuts at random filter frequencies
Description	This occurs in the most recent versions of openMPT, whereas I set filter mode for high pass filter does not produce a smooth transition say for scrolling a high pass filter (having a series of rows say for 128 total for reserving the z80-zff macro), it is not smooth like it should be. LIke, the filter jumps immediately from a standalone filter to suddenly enabling the filter at z90 or something with a very noticable change, instead of a gradual change like "set filter cutoff" does. It does it again with z96 or zb0 with an even higher range, which means I would probably have to put \xx which stinks...Unsure though if it does do any change to the result... Granted I was doing this on an MPTM module with a couple patterns, and instruments with these filters enabled... I am not sure if it affects all the other module formats related to IT. I have not tested this on 1.31.06.
Steps To Reproduce	Create an OpenMPT Module (maybe IT if it is also affected). Import samples. make the instrument envelopes. Modify the ZXX macro config (windows) in View->Zxx macro configuration. Choose Fixed macro Z80-ZFF from the dropdown and enable that exact filter (high pass/f0f002xx). See if you notice any difference with the newly customized filters vs the default z00-z80's f0f000xx.
Tags	No tags attached.

Has the bug occurred in previous versions?	yes
Tested code revision (in case you know it)

Saga Musix 2024-04-02 21:45 administrator ~0005905	I believe you are confusing MIDI macro presets "Z80-ZFF controls resonance" and "Z80-ZFF controls filter mode". The latter changes the current filter mode from lowpass to highpass if the parameter is Z90 or above, while switching back from highpass to lowpass if the value is between Z80 and Z8F. There is no such thing as smooth transition between lowpass and highpass filters (this is not a z-plane filter after all ;). It is expected that this change is immediate and harsh, it's not something you would typically use in the middle of an already playing note. After switching on the highpass filter with Z90, you can then control it with Z00-Z7F commands.

Yalek0391 2024-04-02 21:51 reporter ~0005906	appreciate this explanation. I thought there was something to work around this issue. Thanks saga!!

Date Modified	Username	Field	Change
2024-04-02 21:37	Yalek0391	New Issue
2024-04-02 21:45	Saga Musix	Note Added: 0005905
2024-04-02 21:50	Saga Musix	Severity	major => minor
2024-04-02 21:51	Yalek0391	Note Added: 0005906
2024-04-02 21:53	Saga Musix	Status	new => closed
2024-04-02 21:53	Saga Musix	Resolution	open => no change required