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Cubic interpolation for gradients

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I found this to be equally frustrating in Photoshop and Illustrator - Photoshop's senior developer considers this to be a non-issue, ridiculously enough!


Please observe these two identical gradients in Photoline:


A typical three stop radial gradient: white, #3a3e61, white.


The left version (linear) is what we get in Photoshop, Illustrator, Affinity Designer, and other applications. The right one is the same gradient, but that gradient is set to a cubic interpolation in Photoline. Notice the soft transition between the center colour stop and the outer two stops.


Please consider an option in your gradient editor to assign a cubic interpolation - it makes a huge difference when creating smooth blends with gradients.


Also, I found gradient editing to be a bit painful in Affinity Designer - not as painful as Illustrator or (Gods forbid) Photoshop, but Photoline's gradient editor options are user friendlier and more efficient:


1) colours can be picked by right-mouse clicking a stop, or double-clicking a stop;

2) the eliptical and circular gradients are combined in one gradient tool widget in the view;

3) all properties of the gradient can be directly accessed by right-mouse clicking the widget;

4) gradients can be repeated and mirror repeated;

5) starting point and end points can be consistently moved individually, and holding down ALT allows for moving the entire gradient (this works similarly in AD, but is a bit inconsistent depending on the chosen gradient type - for example it is not possible to move the center point of a radial/elliptical gradient in AD separately from the outer stop - both move).


The conical gradient is nice to have, though, in AD. And nice to see that AD allow for snapping as well (Photoline's gradients also snap to geometry, and so on) - although in Photoline an arbitrary point of the gradient can be snapped as well.


At the very least consider implementing cubic interpolation for gradients in AD. Designers will thank you for this :-)

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No, it is definitely not what I meant.


Instead of duplicating this discussion here, please refer to



Affinity is actually mentioned in that thread as well :-)


Gimp and Krita (while I dislike their gradient editors) even offer five different gradient interpolations, and each gradient segment is individually controllable in regards to the interpolation.


Try it out for yourself in Photoline, Krita, and Gimp.

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Yeah, it's one reason why PL is my main image editor...


I remember that and a couple other threads with Chris. The take away from those threads, to me, is it is possible to be accurate (hit the color stops precisely) but still not be a pleasant blend artistically. And I would rather be artistically pleasing.

My computer is a nothing-special Toshiba laptop with unremarkable specs running Windows 10 64-bit.

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Agreed. It is very quick and easy to arrive at beautiful looking multi-stop gradients in 16bpc mode in Photoline in cubic gradient mode - while in Affinity Designer it is just somewhat awkward, and often required multiple stops to fix things.


I truly hope the developers will at least consider additional gradient stop interpolations.

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Sounds to me like "blend curves". That is, how fast one color mixes to another. Linear mix clearly is not always very useful.

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