Seed-based noise and worldgen

src/worldgen.zig

@@ -0,0 +1,36 @@
+const std = @import("std");
+const math = @import("math.zig");
+
+const Vector2 = math.Vector2;
+
+const Noise = struct {
+    horizontal_scale: f32,
+    value_median: f32,
+    value_amplitude: f32,
+
+    pub fn sample(self: Noise, seed: u64, pos: Vector2) f32 {
+        return math.noise2(seed, pos.divScalar(self.horizontal_scale)) * self.value_amplitude + 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: Vector2) f32 {
+    const main = noise_main.sample(seed, pos);
+    const secondary = noise_secondary.sample(seed, pos);
+    return @round(main + secondary);
+}
+
+pub fn heightI(seed: u64, pos: Vector2) i32 {
+    return @intFromFloat(heightF(seed, pos));
+}