brighten differs from pre v1

[Steve-Mcl]

Has the parameter value definition changed from Jimp 0.x to 1.x?

Expected Behavior

Brightness with a value of 0 should not affect image like it did in v0.x
Brightness with a value of 1 should fully lighten an image like it did in v0.x
Brightness with a value of -1 should fully darken an image like it did in v0.x
Brightness with a value of -0.5 should half darken an image like it did in v0.x
Brightness with a value of 0.5 should half lighten an image like it did in v0.x

Using Jimp V0.x (using Node-RED to simplify testing)

Current Behavior

Brightness with a value of 0 in v1.6 behaves differently - it darkens the image
Brightness with a value of 1 in v1.6 behaves differently - it has little affect on the image
Brightness with a value of -1 correctly fully darkens an image like it did in v0.x
Brightness with a value of -0.5 in v1.6 behaves differently - it FULLY darkens the image
Brightness with a value of 0.5 in v1.6 behaves differently - it half darkens the image

Failure Information (for bugs)

Steps to Reproduce

Demonstrating -0.5 brightness

1. load image
   1. 
2. invert
   1. 
3. apply brightness -0.5
   1. 

Demonstrating -0.0 brightness

1. load image
   1. 
2. invert
   1. 
3. apply brightness -0.0
   1. 

Demonstrating 1.0 brightness

1. load image
   1. 
2. invert
   1. 
3. apply brightness 1.0
   1. 

Context

• Jimp Version: 1.6.0
• Operating System: Win 11
• Node version: 18

Failure Logs

[Steve-Mcl]

Can anyone at least acknowledge there was a conscious decision to change how brightness function works or if it is a bug?

If it is a confirmed change, I can work around this safe in the knowledge it wont be changed.

If it turns out the brightness parameter has a regression that will be reverted, I dont want to introduce a latent bug in my code!

Anyone?

---

Pre V1:

image.brightness( val ); // adjust the brighness by a value -1 to +1

REF:

jimp/packages/jimp/README.md

Line 217 in a4a8d63

image.brightness( val ); // adjust the brighness by a value -1 to +1

This lines up with my expectation and experience.

Post V1:

brightness()
brightness(val): Jimp

Adjusts the brightness of the image

REF: https://jimp-dev.github.io/jimp/api/jimp/classes/jimp/#brightness

[andrewdolphin]

See breaking changes for v1.1.2, new behaviour is as expected

https://github.com/jimp-dev/jimp/releases/tag/v1.1.2

[Steve-Mcl]

See breaking changes for v1.1.2, new behaviour is as expected

https://github.com/jimp-dev/jimp/releases/tag/v1.1.2

Ok, thanks. I didn't find that since it was a patch version change

Do you not follow semver rules?