trying to re-implement chunk_manager

src/generation/simple_heightmap.rs

@@ -0,0 +1,79 @@
+use fastnoise_lite::{FastNoiseLite, FractalType};
+use godot::{classes::class_macros::private::virtuals::Os::Vector3i, global::pow};
+
+use crate::{chunk::ChunkColumn, generation::generator::SurfaceGenerator};
+
+pub struct SimpleSurfaceGenerator {
+    noise: FastNoiseLite,
+    surface_height: u32,
+    chunk_size: Vector3i,
+}
+
+impl SimpleSurfaceGenerator {
+    pub fn new(seed: i32, frequency: f32, surface_height: u32, chunk_size: Vector3i) -> Self {
+        let mut noise = FastNoiseLite::new();
+        noise.frequency = frequency;
+        noise.noise_type = fastnoise_lite::NoiseType::OpenSimplex2;
+        noise.seed = seed;
+        noise.set_fractal_type(Some(FractalType::Ridged));
+        noise.set_fractal_octaves(Some(4));
+        Self {
+            noise,
+            surface_height,
+            chunk_size,
+        }
+    }
+
+    #[inline]
+    pub fn normalize_value(value: f32) -> f32 {
+        (value + 1.0) * 0.5 // [0, value]
+    }
+}
+
+impl SurfaceGenerator for SimpleSurfaceGenerator {
+    fn generate(&self, column: &mut ChunkColumn) {
+        let size_x = self.chunk_size.x;
+        let size_z = self.chunk_size.z;
+
+        let base_x = column.world_position.0 * size_x;
+        let base_z = column.world_position.1 * size_z;
+
+        let freq = 1.0 / 32.0;
+
+        let column_height = self.chunk_size.y * self.surface_height as i32;
+
+        for x in 0..self.chunk_size.x {
+            for z in 0..self.chunk_size.z {
+                // world coordinates of this column
+                let world_x = base_x + x;
+                let world_z = base_z + z;
+
+                let noise = self
+                    .noise
+                    .get_noise_2d(world_x as f32 * freq, world_z as f32 * freq);
+
+                let noise = Self::normalize_value(noise);
+
+                let height = (noise.powi(2) * column_height as f32) as i32;
+
+                for y in 1..=height {
+                    column.set_voxel(Vector3i::new(world_x, y, world_z), true);
+                }
+            }
+        }
+    }
+    fn sample_voxel(&self, pos: Vector3i) -> bool {
+        let freq = 1.0 / 32.0;
+
+        let noise = self
+            .noise
+            .get_noise_2d(pos.x as f32 * freq, pos.z as f32 * freq);
+
+        let noise = Self::normalize_value(noise);
+
+        let column_height = self.chunk_size.y * self.surface_height as i32;
+        let height = (noise.powi(2) * column_height as f32) as i32;
+
+        pos.y <= height
+    }
+}