New icons for Gradient and GradientTexture resources

[gongpha]

These new icons will look consistent with another icon.

Old

New

Edit : Wait for #42855 to be merged first.

[akien-mga]

The GradientTexture icon looks good, but the Gradient icon is too similar to GradientTexture with the rectangular outline which only differs by a few pixels.

[Calinou]

Maybe GradientTexture's gradient could be flipped to be in the opposite direction?

[gongpha]

Sounds good, Or should Gradient's icon rotate like an old one ?

[gongpha]

Modified.

[Xrayez]

I'm not sure whether GradientTexture2D is going to be merged at all in Godot: #42855, but then I'm not sure what should be the icon for 2D texture, perhaps the old icon of GradientTexture should be the new icon for GradientTexture2D? 😃

In any case, that's something I'd like to implement in either case (in Goost), so worth to discuss the design in relation to 2D texture.

[gongpha]

@Xrayez When should the #42855 be merged ?

[Xrayez]

@gongpha godotengine/godot-proposals#1677 has to be officially approved first, technically could be merged right now, but there are other limitations which would be good to resolve to make it robust: #43015.

[gongpha]

@Xrayez Meanwhile, I made a local commit with GradientTexture2D's icon. I designed it to look different from GradientTexture. But I still use grey as an icon color like the original one. Because it doesn't associate with Node2D nodes.

However, I will sit here for #42855. When it ready, I will push them here. 🙂

[Xrayez]

@gongpha just letting you know that I've added GradientTexture2D in Goost with goostengine/goost#43, for now I'm just using the same GradientTexture icon in editor/icons/icon_gradient_texture_2d.svg, so feel free to contribute there as well. 🙂

Of course I'd still prefer #42855 to get merged too.

[gongpha]

@Xrayez I'm currently working on these icons. I read your commits in goostengine/goost#43. I saw that your changes include radial gradient and I'm still hesitating with these icons. You can help me pick one with the best fit for its purpose !

[Xrayez]

@gongpha thanks, I think the diagonal one is a good fit, this signifies that linear gradient can have arbitrary direction in 2D. The linear gradient is the default one so it's not necessary to have a radial icon displayed (many other types could be implemented in the future as well...)

[gongpha]

Current :

[Calinou]

I think the new icons are easy enough to distinguish from each other.

[akien-mga]

Thanks!

[akien-mga]

Cherry-picked for 3.4.