maiden stone
I couldn't figure out how to create a usable variable value and there are no example around either.
import "core:math/fixed"
Fixed :: fixed.Fixed16_16
Vec2Fixed :: [2]Fixed
main :: proc() {
vec2 := Vec2Fixed {
???,
???,
}
}
ocean hill
You can initialize it from an f64 with init_from_f64:
vec2: Vec2Fixed
fixed.init_from_f64(&vec2[0], 1.25)
fixed.init_from_f64(&vec2[1], 2.75)
Or from an integer with init_from_parts by passing a fraction of 0
vec2: Vec2Fixed
fixed.init_from_parts(&vec2[0], 123, 0)
fixed.init_from_parts(&vec2[1], 234, 0)
For the fraction parameter of init_from_parts, it's an integer value that's basically the fractional part multiplied by 1 << Fraction_Width (which is equivalent to 2^Fraction_Width):
vec2: Vec2Fixed
fixed.init_from_parts(&vec2[0], 1, 16384) // 1.25
fixed.init_from_parts(&vec2[1], 2, 49152) // 2.75
// you can also multiply a float constant, and the compiler will allow it *if* it can be represented exactly
fixed.init_from_parts(&vec2[0], 1, 0.25 * (1 << 16)) // also 1.25
fixed.init_from_parts(&vec2[1], 2, 0.75 * (1 << 16)) // also 2.75
//fixed.init_from_parts(&vec2[1], 3, 0.1 * (1 << 16)) // error: would truncate
Alternatively, it's just a struct so you can set the backing value directly:
vec2 := Vec2Fixed {
{65536 + 16384}, // 1.25
{2.75 * (1 << 16)}, // 2.75, as above must be exact for the compiler to allow this
}