Animation: shear left slider #106521

New operator for the slider tool in the Graph Editor.

It affects the value of selected keys linearly keeping the same relationship between them using the left key as anchor. The purpose is to keep the animation on the selected keys but matching the neigboring poses.

The tool I have used that inspired this slider is a lattice in the graph editor. So, imagine you have a simple lattice without subdivision affecting the selected keys (a bounding box), and then push the right side of the lattice up or down.

It uses the structure already created by @ChrisLend. The main functionality change is in 'keyframes_general.c', the rest for the most part just follows what he did.

New operator for the slider tool in the Graph Editor. It affects the value of selected keys linearly keeping the same relationship between them using the left key as anchor. The purpose is to keep the animation on the selected keys but matching the neigboring poses. The tool I have used that inspired this slider is a lattice in the graph editor. So, imagine you have a simple lattice without subdivision affecting the selected keys (a bounding box), and then push the right side of the lattice up or down. It uses the structure already created by @ChrisLend. The main functionality change is in 'keyframes_general.c', the rest for the most part just follows what he did.

shear_left_slider.gif

961 KiB

I see nothing wrong with it except a small typo :)
adding sybren as a reviewer for the final check

I see nothing wrong with it except a small typo :) adding sybren as a reviewer for the final check

I see you approved it, did you change the typo? don't know if I should publish the error correction and ask for a new review.

Well, I pushed the typo correction just in case.

I see you approved it, did you change the typo? don't know if I should publish the error correction and ask for a new review.

I didn't change anything, but if the changes are so super tiny, the way it is usually handled is that the reviewer accepts it with the note it should be changed. And right after the change it can be commited because it's already accepted :)

In this case wait for Sybren to look over it though

> I see you approved it, did you change the typo? don't know if I should publish the error correction and ask for a new review. I didn't change anything, but if the changes are so super tiny, the way it is usually handled is that the reviewer accepts it with the note it should be changed. And right after the change it can be commited because it's already accepted :) In this case wait for Sybren to look over it though

What are the future plans for this operator? Would it ever need to be able to sheer the other side as well?

  /* The factor goes from 0 to 1, but for this tool it needs to go from -1 to 1. */

Would it make sense to turn this into a bidirectional slider? That way the slider itself also goes from -100% to +100%, with a neutral 0% starting point (instead of 50%).

I'm also not 100% convinced by the "sheer left", but that might be a personal thing. Since it's the right-hand side of the selection area that is affected the most, wouldn't this be more of a "sheer right"?

What are the future plans for this operator? Would it ever need to be able to sheer the other side as well? ``` /* The factor goes from 0 to 1, but for this tool it needs to go from -1 to 1. */ ``` Would it make sense to turn this into a bidirectional slider? That way the slider itself also goes from -100% to +100%, with a neutral 0% starting point (instead of 50%). I'm also not 100% convinced by the "sheer left", but that might be a personal thing. Since it's the right-hand side of the selection area that is affected the most, wouldn't this be more of a "sheer right"?

What are the future plans for this operator? Would it ever need to be able to sheer the other side as well?
Would it make sense to turn this into a bidirectional slider? That way the slider itself also goes from -100% to +100%, with a neutral 0% starting point (instead of 50%).

I changed it to bidirectional and it worked. I need to revisit other sliders because I did this on some but didn't do what I was expecting. Must be something wrong I did.

I'm also not 100% convinced by the "sheer left", but that might be a personal thing. Since it's the right-hand side of the selection area that is affected the most, wouldn't this be more of a "sheer right"?

That is my instinct too, but every tool on the slider uses left or right based on where the reference point is. For example Scale left feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it.

``` What are the future plans for this operator? Would it ever need to be able to sheer the other side as well? Would it make sense to turn this into a bidirectional slider? That way the slider itself also goes from -100% to +100%, with a neutral 0% starting point (instead of 50%). ``` I changed it to bidirectional and it worked. I need to revisit other sliders because I did this on some but didn't do what I was expecting. Must be something wrong I did. ``` I'm also not 100% convinced by the "sheer left", but that might be a personal thing. Since it's the right-hand side of the selection area that is affected the most, wouldn't this be more of a "sheer right"? ``` That is my instinct too, but every tool on the slider uses `left` or `right` based on where the reference point is. For example `Scale left` feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it.

That is my instinct too, but every tool on the slider uses left or right based on where the reference point is. For example Scale left feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it.

I think this should be discussed in the A&R meeting, there is no clear right or wrong to it

> That is my instinct too, but every tool on the slider uses `left` or `right` based on where the reference point is. For example `Scale left` feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it. > I think this should be discussed in the A&R meeting, there is no clear right or wrong to it

I changed it to bidirectional and it worked. I need to revisit other sliders because I did this on some but didn't do what I was expecting. Must be something wrong I did.

It should expand the slider's range from [0, 1] to [-1, 1], nothing more. Of course the code has to change as well, since the 'neutral' point changes from 0.5 to 0.0 and the range of the sider becomes twice a large.

That is my instinct too, but every tool on the slider uses left or right based on where the reference point is. For example Scale left feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it.

I've put it on the module meeting agenda as @ChrisLend suggested 👍

Also, if there is going to be a "shear right" operator as well, I think the code would need some changes to avoid future code duplication. Some of the functions would need to be renamed to no longer have left in their name (like shear_left_fcurve_segment). The operator can get an extra parameter to indicate the left/right side (probably a two-value enum is best), which is then passed down to the shearing functions.

@AresDeveaux would you need/want some help with this restructuring?

> I changed it to bidirectional and it worked. I need to revisit other sliders because I did this on some but didn't do what I was expecting. Must be something wrong I did. It should expand the slider's range from `[0, 1]` to `[-1, 1]`, nothing more. Of course the code has to change as well, since the 'neutral' point changes from `0.5` to `0.0` and the range of the sider becomes twice a large. > That is my instinct too, but every tool on the slider uses `left` or `right` based on where the reference point is. For example `Scale left` feels the same as this one, scale toward the right side of the selected keys because uses the left neighboring pose as a reference. The naming convention came from how it is in similar tools in the industry but let me know if I should change it. I've put it on the module meeting agenda as @ChrisLend suggested :+1: Also, if there is going to be a "shear right" operator as well, I think the code would need some changes to avoid future code duplication. Some of the functions would need to be renamed to no longer have `left` in their name (like `shear_left_fcurve_segment`). The operator can get an extra parameter to indicate the left/right side (probably a two-value enum is best), which is then passed down to the shearing functions. @AresDeveaux would you need/want some help with this restructuring?

small thing about the factor soft minimum
no need to re-review from my side after that change

small thing about the factor soft minimum no need to re-review from my side after that change

Also, if there is going to be a "shear right" operator as well, I think the code would need some changes to avoid future code duplication. Some of the functions would need to be renamed to no longer have left in their name (like shear_left_fcurve_segment). The operator can get an extra parameter to indicate the left/right side (probably a two-value enum is best), which is then passed down to the shearing functions.

@AresDeveaux would you need/want some help with this restructuring?

hey @dr.sybren , I think I might need some help with that. The function modification is something I could do, but I'm not sure I know how to add a parameter to an operator in Blender.

``` Also, if there is going to be a "shear right" operator as well, I think the code would need some changes to avoid future code duplication. Some of the functions would need to be renamed to no longer have left in their name (like shear_left_fcurve_segment). The operator can get an extra parameter to indicate the left/right side (probably a two-value enum is best), which is then passed down to the shearing functions. @AresDeveaux would you need/want some help with this restructuring? ``` hey @dr.sybren , I think I might need some help with that. The function modification is something I could do, but I'm not sure I know how to add a parameter to an operator in Blender.

The same will need to be done with "Scale left", 'Scale right" and "Scale average" then.

You can check the Graph_OT_decimate operator for an example on how an enum property is added.
line 528 in graph_slider_ops.c

You can check the `Graph_OT_decimate` operator for an example on how an enum property is added. line 528 in `graph_slider_ops.c`

Landed in #111735: Animation: Shear operator for Graph Editor

Landed in [#111735: Animation: Shear operator for Graph Editor](https://projects.blender.org/blender/blender/pulls/111735)

 @ -1063,0 +1163,4 @@
   ot->name = "Shear Left Keyframes";
   ot->idname = "GRAPH_OT_shear_left";
   ot->description =
       "Affects the value of the keys linealy keeping the same \n\

 @ -1063,0 +1184,4 @@
                        FLT_MAX,
                        "Curve Bend",
                        "Control the bend of the curve",
 .0f,

Animation: shear left slider #106521

Reviewers

Pull request closed

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Animation: shear left slider #106521

Reviewers

Pull request closed