starting procedural generation

Cargo.toml

@@ -4,3 +4,4 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+noise = "0.9.0"

TODO.md

@@ -0,0 +1,69 @@
+# TODO List for a Minecraft-Like Terrain Generator in Rust
+
+## 1. Define Objectives and Requirements
+- **Features:**
+  - Global terrain generation (overall elevation)
+  - Local detail (surface variations)
+  - Biome transitions and optionally cave systems
+- **Technical Constraints:**
+  - Chunk dimensions (e.g., 16×16 blocks horizontally with a fixed vertical height)
+  - Memory management (chunk caching, on-demand generation)
+  - Server integration (protocol, networking, etc.)
+- **Output Format:**
+  - How to represent the world (e.g., a 3D array of block types)
+  - Block types (Air, Grass, Dirt, Stone, Water, etc.)
+
+## 2. Research and Select Noise Algorithms
+- Study noise algorithms such as Perlin and Simplex.
+- Understand Fractal Brownian Motion (fBm) to combine multiple octaves.
+- Define parameters like frequency, amplitude, persistence, number of octaves, and scaling factors.
+
+## 3. Set Up Your Rust Project
+- Create a new project with Cargo.
+- Add necessary dependencies in `Cargo.toml` (e.g., the `noise` crate).
+- Set up version control (Git).
+
+## 4. Implement Basic Noise Generation
+- Write a simple prototype to generate noise values.
+- Use a scaling factor to avoid sampling only on integer coordinates.
+- Test with a fixed seed for reproducibility.
+
+## 5. Implement Fractal Brownian Motion (fBm)
+- Create a function to combine multiple noise octaves.
+- Adjust parameters (octaves, persistence, etc.) and test the results.
+
+## 6. Map Noise to Terrain Height
+- Convert normalized noise values (e.g., from -1 to 1) to block heights.
+- Define a mapping strategy (for example, scaling to a maximum height).
+
+## 7. Design the Chunk Data Structure
+- Decide on chunk dimensions (e.g., 16×16×128).
+- Create a simple structure to represent blocks (using enums or similar).
+
+## 8. Generate Chunks Based on Noise
+- For each (x, z) coordinate in a chunk:
+  - Calculate the noise value.
+  - Map it to a terrain height.
+  - Fill in blocks based on the height (e.g., surface, sub-surface, stone).
+- Keep the code modular and avoid overcomplicating early on.
+
+## 9. Test and Visualize the Generated Terrain
+- Write unit tests for noise functions and terrain mapping.
+- Create a simple visualization (e.g., a 2D height map printed to the console or exporting data for external tools).
+- Verify that parameter adjustments produce the expected variations.
+
+## 10. Integrate the Generator into Your Server Architecture
+- Implement on-demand chunk generation as the player moves.
+- Cache generated chunks (in memory or on disk) to avoid re-computation.
+- Consider multithreading or asynchronous processing for parallel generation.
+
+## 11. Optimize and Refine
+- Profile the terrain generation for performance bottlenecks.
+- Fine-tune noise parameters and mapping logic.
+- Plan future enhancements (biomes, caves, advanced block types).
+
+## 12. Document and Maintain the Codebase
+- Document your functions, parameters, and overall architecture.
+- Use version control to track changes and manage iterative improvements.
+- Keep your code modular for easy future enhancements.
+

src/main.rs

@@ -1,3 +1,80 @@
-fn main() {
-    println!("Hello, world!");
+// Example Code
+
+use noise::{NoiseFn, Perlin};
+#[derive(Debug, Clone, Copy)]
+enum BlockType {
+    Air,
+    Grass,
+    Dirt,
+    Stone,
+    Water,
+}
+const CHUNK_SIZE: usize = 16;
+const CHUNK_HEIGHT: usize = 128;
+
+type Chunk = Vec<Vec<Vec<BlockType>>>;
+
+fn main() {
+    let perlin = Perlin::new(42);
+    let scale = 0.1;
+    let x = 10.0 * scale;
+    let y = 20.0 * scale;
+    let noise_value = perlin.get([x, y]);
+    println!("Noise value: {}", noise_value);
+}
+fn fbm(perlin: &Perlin, x: f64, y: f64, octaves: u32, persistence: f64) -> f64 {
+    let mut total = 0.0;
+    let mut amplitude = 1.0;
+    let mut frequency = 1.0;
+    let mut max_value = 0.0;
+
+    for _ in 0..octaves {
+        total += perlin.get([x * frequency, y * frequency]) * amplitude;
+        max_value += amplitude;
+        amplitude *= persistence;
+        frequency *= 2.0;
+    }
+    total / max_value
+}
+
+fn map_noise_to_height(noise_value: f64) -> usize {
+    let normalized = (noise_value + 1.0) / 2.0; // map from [-1, 1] to [0, 1]
+    let max_height = 128;
+    (normalized * max_height as f64) as usize
+}
+fn generate_chunk(perlin: &Perlin, chunk_x: i32, chunk_z: i32) -> Chunk {
+    let mut chunk = vec![vec![vec![BlockType::Air; CHUNK_HEIGHT]; CHUNK_SIZE]; CHUNK_SIZE];
+    let scale = 0.1;
+
+    for local_x in 0..CHUNK_SIZE {
+        for local_z in 0..CHUNK_SIZE {
+            let world_x = chunk_x * CHUNK_SIZE as i32 + local_x as i32;
+            let world_z = chunk_z * CHUNK_SIZE as i32 + local_z as i32;
+            let noise_value = fbm(
+                perlin,
+                world_x as f64 * scale,
+                world_z as f64 * scale,
+                4,
+                0.5,
+            );
+            let height = map_noise_to_height(noise_value);
+
+            for y in 0..CHUNK_HEIGHT {
+                if y > height {
+                    chunk[local_x][local_z][y] = if y < 64 {
+                        BlockType::Water
+                    } else {
+                        BlockType::Air
+                    };
+                } else if y == height {
+                    chunk[local_x][local_z][y] = BlockType::Grass;
+                } else if y > height.saturating_sub(3) {
+                    chunk[local_x][local_z][y] = BlockType::Dirt;
+                } else {
+                    chunk[local_x][local_z][y] = BlockType::Stone;
+                }
+            }
+        }
+    }
+    chunk
 }