const std = @import("std");

const math = @import("math.zig");
const vm = @import("vecmath");

const Noise = struct {
    horizontal_scale: f32,
    value_median: f32,
    value_amplitude: f32,

    pub fn sample(self: Noise, seed: u64, pos: vm.Vector2) f32 {
        return math.noise2(seed, pos.divScalar(self.horizontal_scale)) * self.value_amplitude + self.value_median;
    }

    pub fn samplev(self: Noise, seed: u64, pos: vm.Vector2x8) vm.f32x8 {
        return math.noise2x8(seed, pos.divScalarSingle(self.horizontal_scale)) * vm.ps(self.value_amplitude) + vm.ps(self.value_median);
    }
};

const noise_main: Noise = .{
    .horizontal_scale = 80,
    .value_median = 7,
    .value_amplitude = 5,
};

const noise_secondary: Noise = .{
    .horizontal_scale = 15,
    .value_median = 0,
    .value_amplitude = 0.5,
};

pub fn heightF(seed: u64, pos: vm.Vector2) f32 {
    const main = noise_main.sample(seed, pos);
    const secondary = noise_secondary.sample(seed, pos);
    return @round(main + secondary);
}

pub fn heightFv(seed: u64, pos: vm.Vector2x8) vm.f32x8 {
    const main = noise_main.samplev(seed, pos);
    const secondary = noise_secondary.samplev(seed, pos);
    return @round(main + secondary);
}

pub fn heightI(seed: u64, pos: vm.Vector2) i32 {
    return @intFromFloat(heightF(seed, pos));
}

pub fn heightIv(seed: u64, pos: vm.Vector2x8) vm.i32x8 {
    return @intFromFloat(heightFv(seed, pos));
}