From 910f21b9b9d4cc0af22094668e1dbf4a2c627ac6 Mon Sep 17 00:00:00 2001
From: Namonay <thek7995@gmail.com>
Date: Fri, 23 May 2025 23:48:17 +0200
Subject: [PATCH] added base of procedural generation

---
 Application/Noise.cpp | 86 ++++++++++++++++++++++++++++++++++++++++++-
 Application/Noise.h   | 14 ++++++-
 2 files changed, 96 insertions(+), 4 deletions(-)

diff --git a/Application/Noise.cpp b/Application/Noise.cpp
index e20c82a..13c05c1 100644
--- a/Application/Noise.cpp
+++ b/Application/Noise.cpp
@@ -1,13 +1,95 @@
 #include <Noise.h>
 #include <Block.h>
+#include <cstdint>
+#include <random>
+
+Noise::Noise(const std::uint32_t seed): seed(std::mt19937(seed))
+{
+	InitPermutation();
+}
+
+void Noise::InitPermutation(void)
+{
+	std::array<int, 256> permutations;
+
+	for (int i = 0; i < 256; ++i)
+		permutations[i] = i;
+	std::shuffle(permutations.begin(), permutations.end(), seed);
+	for (int i = 0; i < 256; ++i) 
+	{
+		this->perms[i] = permutations[i];
+		this->perms[i + 256] = permutations[i];
+	}
+	for (int val: this->perms)
+	{
+		std::cout << val << " ";
+	}
+	std::cout << std::endl;
+	std::cout << perlin2D(0, 0) << std::endl;
+	std::cout << perlin2D(20, 20) << std::endl;
+	std::cout << perlin2D(150, 150) << std::endl;
+	std::cout << perlin2D(0.078f, 0.4f) << std::endl;
+
+}
+
+float Noise::fade(float t)
+{
+
+	return t * t * t * (t * (t * 6 - 15) + 10);
+}
+
+float Noise::lerp(float a, float b, float t)
+{
+	return (a + t * (b - a));
+}
+
+float Noise::grad(int hash, float x, float y) 
+{
+    int h = hash & 7; 
+    float u = h < 4 ? x : y;
+    float v = h < 4 ? y : x;
+
+    return ((h & 1) ? -u : u) + ((h & 2) ? -v : v);
+}
+
+int Noise::perlin2D(int x, int y) {
+    float scaledX = static_cast<float>(x) * 0.01f;
+    float scaledY = static_cast<float>(y) * 0.01f;
+    return floor(perlin2D(scaledX, scaledY) * 255.0f);
+}
+
+float Noise::perlin2D(float x, float y) {
+    int xi = (int)floor(x) & 255;
+    int yi = (int)floor(y) & 255;
+
+    float xf = x - floor(x);
+    float yf = y - floor(y);
+
+    float u = fade(xf);
+    float v = fade(yf);
+
+    int aa = perms[perms[xi] + yi];
+    int ab = perms[perms[xi] + yi + 1];
+    int ba = perms[perms[xi + 1] + yi];
+    int bb = perms[perms[xi + 1] + yi + 1];
+
+    float x1 = lerp(grad(aa, xf,     yf),
+                    grad(ba, xf - 1, yf), u);
+    float x2 = lerp(grad(ab, xf,     yf - 1),
+                    grad(bb, xf - 1, yf - 1), u);
+
+    return (lerp(x1, x2, v) + 1.0f) / 2.0f; // Normalize to [0, 1]
+}
 
 [[nodiscard]] std::array<std::uint32_t, CHUNK_SIZE.y> Noise::GetHeight(Scop::Vec2i pos)
 {
 	std::array<std::uint32_t, CHUNK_SIZE.y> data;
 	std::memset(data.data(), static_cast<std::uint32_t>(BlockType::Air), data.size() * sizeof(std::uint32_t));
 
-	std::uint32_t height = std::abs(std::sin((float)pos.x / 20.0f) * std::cos((float)pos.y / 20.0f) * 60.0f) + 1;
-
+	
+	//std::uint32_t height = std::abs(std::sin((float)pos.x / 20.0f) * std::cos((float)pos.y / 20.0f) * 60.0f) + 1;
+	
+	std::uint32_t height = perlin2D(pos.x, pos.y); 
 	// Must not exceed CHUNK_SIZE.y
 	for(std::uint32_t y = 0; y < std::min(height, CHUNK_SIZE.y); y++)
 	{
diff --git a/Application/Noise.h b/Application/Noise.h
index 64da228..b1ae656 100644
--- a/Application/Noise.h
+++ b/Application/Noise.h
@@ -4,17 +4,27 @@
 #include <ScopMaths.h>
 
 #include <Chunk.h>
+#include <array>
+#include <random>
 
+#define NOISE_SIZE 512
 class Noise
 {
 	public:
-		Noise() = default;
+		Noise(const std::uint32_t seed = 42);
 
 		[[nodiscard]] std::array<std::uint32_t, CHUNK_SIZE.y> GetHeight(Scop::Vec2i pos);
-
+		float perlin2D(float x, float y);
+		int perlin2D(int x, int y);
 		~Noise() = default;
 
 	private:
+		std::mt19937 seed;
+		std::array<int, NOISE_SIZE> perms;
+		void InitPermutation(void);
+		float fade(float t);
+		float lerp(float a, float b, float t);
+		float grad(int hash, float x, float y);
 };
 
 #endif