# Objective
Add interpolation in HSL and HSV colour spaces for UI gradients.
## Solution
Added new variants to `InterpolationColorSpace`: `Hsl`, `HslLong`,
`Hsv`, and `HsvLong`, along with mix functions to the `gradients` shader
for each of them.
#### Limitations
* Didn't include increasing and decreasing path support, it's not
essential and can be done in a follow up if someone feels like it.
* The colour conversions should really be performed before the colours
are sent to the shader but it would need more changes and performance is
good enough for now.
## Testing
```cargo run --example gradients```
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