X-Git-Url: https://git.localhorst.tv/?a=blobdiff_plain;ds=sidebyside;f=src%2Fworld%2FBlockType.hpp;h=f1b887d3eabc56e998fd64917c8a661df9df52b9;hb=fda38181732e58537331c919dd699eaa830ead50;hp=3ca170a200ba65367ff604bfbada3645456714b1;hpb=1a8d4d31ef0a094ef6488127c5f873040151cb57;p=blank.git

diff --git a/src/world/BlockType.hpp b/src/world/BlockType.hpp
index 3ca170a..f1b887d 100644
--- a/src/world/BlockType.hpp
+++ b/src/world/BlockType.hpp
@@ -9,6 +9,7 @@
 #include "../model/Shape.hpp"
 
 #include <glm/glm.hpp>
+#include <limits>
 #include <vector>
 
 
@@ -58,20 +59,58 @@ struct BlockType {
 	// generation properties
 	/// whether to use this block in generation at all
 	bool generate;
+
 	// min/mid/max points for the respective properties
 	// should all be in the (-1,1) range
-	float min_solidity;
-	float mid_solidity;
-	float max_solidity;
-	float min_humidity;
-	float mid_humidity;
-	float max_humidity;
-	float min_temperature;
-	float mid_temperature;
-	float max_temperature;
-	float min_richness;
-	float mid_richness;
-	float max_richness;
+	class Distribution {
+
+	public:
+		Distribution(float min, float mid, float max)
+		: xmin(min), xmid(mid), xmax(max) { Update(); }
+
+		bool Valid(float x) const noexcept {
+			return x >= xmin && x <= xmax;
+		}
+		float Map(float x) const noexcept {
+			// previous algo as was used by Generator
+			//return 4.0f - ((x - xmid) * (x - xmid));
+
+			// linear mapping of [min,mid,max] to [-1,0,1]
+			x -= xmid;
+			x *= (x < 0) ? inv_neg : inv_pos;
+
+			// smoothing: x^4 - 2x^2 + 1
+			x *= x;
+			return x * x - 2.0f * x + 1.0f;
+		}
+
+		void Min(float m) noexcept { xmin = m; Update(); }
+		float Min() const noexcept { return xmin; }
+		void Mid(float m) noexcept { xmid = m; Update(); }
+		float Mid() const noexcept { return xmid; }
+		void Max(float m) noexcept { xmax = m; Update(); }
+		float Max() const noexcept { return xmax; }
+
+	private:
+		void Update() {
+			float abs_min = std::abs(xmin - xmid);
+			inv_neg = abs_min < std::numeric_limits<float>::epsilon() ? 0.0f : 1.0f / abs_min;
+			float abs_max = std::abs(xmax - xmid);
+			inv_pos = abs_max < std::numeric_limits<float>::epsilon() ? 0.0f : 1.0f / abs_max;
+		}
+
+		float xmin;
+		float xmid;
+		float xmax;
+		float inv_neg;
+		float inv_pos;
+
+	};
+
+	Distribution solidity;
+	Distribution humidity;
+	Distribution temperature;
+	Distribution richness;
 	/// commonness factor, random chance is multiplied by this
 	float commonness;