Whether to add .0 on CGFloat parameter

Years ago, Apple tutorial included .0 when initializing CGFloat. However, this pattern has since been removed.

CardView(scrum: scrum)
            .background(scrum.theme.mainColor)
            .previewLayout(.fixed(width: 400, height: 60))

So, I tested the performance difference between the two cases.

import CoreGraphics

let start = CFAbsoluteTimeGetCurrent()
for _ in 0..<1_000_000 {
    let _ = CGFloat(10) * 2.5
}
let end = CFAbsoluteTimeGetCurrent()
print("Without .0: \(end - start)")

let start2 = CFAbsoluteTimeGetCurrent()
for _ in 0..<1_000_000 {
    let _ = CGFloat(10.0) * 2.5
}
let end2 = CFAbsoluteTimeGetCurrent()
print("With .0: \(end2 - start2)")

Result

Without .0: 0.1854790449142456
With .0: 0.1740100383758545

The difference was 0.01 seconds over one million times iterations.

For reference,

10 -> the value is converted from Int to CGFloat
10.0 -> from Double to CGFloat

Conclusion

I decided to follow Apple’s updated tutorial style and omit .0 because the performance difference is negligible.