From 4fcd000e20a26120349184cb9d40342b7876e6b8 Mon Sep 17 00:00:00 2001
From: rubenwardy <rw@rubenwardy.com>
Date: Thu, 21 Jan 2021 19:08:06 +0000
Subject: [PATCH] MgOre: Fix invalid field polymorphism (#10846)

---
 src/mapgen/mg_ore.h             | 47 ++++++++++++++-------------------
 src/script/lua_api/l_mapgen.cpp |  2 +-
 2 files changed, 21 insertions(+), 28 deletions(-)

diff --git a/src/mapgen/mg_ore.h b/src/mapgen/mg_ore.h
index 76420fab4..a58fa9bfe 100644
--- a/src/mapgen/mg_ore.h
+++ b/src/mapgen/mg_ore.h
@@ -52,7 +52,7 @@ extern FlagDesc flagdesc_ore[];
 
 class Ore : public ObjDef, public NodeResolver {
 public:
-	static const bool NEEDS_NOISE = false;
+	const bool needs_noise;
 
 	content_t c_ore;                  // the node to place
 	std::vector<content_t> c_wherein; // the nodes to be placed in
@@ -68,7 +68,7 @@ public:
 	Noise *noise = nullptr;
 	std::unordered_set<biome_t> biomes;
 
-	Ore() = default;;
+	explicit Ore(bool needs_noise): needs_noise(needs_noise) {}
 	virtual ~Ore();
 
 	virtual void resolveNodeNames();
@@ -83,17 +83,17 @@ protected:
 
 class OreScatter : public Ore {
 public:
-	static const bool NEEDS_NOISE = false;
+	OreScatter() : Ore(false) {}
 
 	ObjDef *clone() const;
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OreSheet : public Ore {
 public:
-	static const bool NEEDS_NOISE = true;
+	OreSheet() : Ore(true) {}
 
 	ObjDef *clone() const;
 
@@ -101,14 +101,12 @@ public:
 	u16 column_height_max;
 	float column_midpoint_factor;
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OrePuff : public Ore {
 public:
-	static const bool NEEDS_NOISE = true;
-
 	ObjDef *clone() const;
 
 	NoiseParams np_puff_top;
@@ -116,55 +114,50 @@ public:
 	Noise *noise_puff_top = nullptr;
 	Noise *noise_puff_bottom = nullptr;
 
-	OrePuff() = default;
+	OrePuff() : Ore(true) {}
 	virtual ~OrePuff();
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OreBlob : public Ore {
 public:
-	static const bool NEEDS_NOISE = true;
-
 	ObjDef *clone() const;
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	OreBlob() : Ore(true) {}
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OreVein : public Ore {
 public:
-	static const bool NEEDS_NOISE = true;
-
 	ObjDef *clone() const;
 
 	float random_factor;
 	Noise *noise2 = nullptr;
 	int sizey_prev = 0;
 
-	OreVein() = default;
+	OreVein() : Ore(true) {}
 	virtual ~OreVein();
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OreStratum : public Ore {
 public:
-	static const bool NEEDS_NOISE = false;
-
 	ObjDef *clone() const;
 
 	NoiseParams np_stratum_thickness;
 	Noise *noise_stratum_thickness = nullptr;
 	u16 stratum_thickness;
 
-	OreStratum() = default;
+	OreStratum() : Ore(false) {}
 	virtual ~OreStratum();
 
-	virtual void generate(MMVManip *vm, int mapseed, u32 blockseed,
-		v3s16 nmin, v3s16 nmax, biome_t *biomemap);
+	void generate(MMVManip *vm, int mapseed, u32 blockseed,
+			v3s16 nmin, v3s16 nmax, biome_t *biomemap) override;
 };
 
 class OreManager : public ObjDefManager {
diff --git a/src/script/lua_api/l_mapgen.cpp b/src/script/lua_api/l_mapgen.cpp
index 498859f14..fad08e1f6 100644
--- a/src/script/lua_api/l_mapgen.cpp
+++ b/src/script/lua_api/l_mapgen.cpp
@@ -1335,7 +1335,7 @@ int ModApiMapgen::l_register_ore(lua_State *L)
 	lua_getfield(L, index, "noise_params");
 	if (read_noiseparams(L, -1, &ore->np)) {
 		ore->flags |= OREFLAG_USE_NOISE;
-	} else if (ore->NEEDS_NOISE) {
+	} else if (ore->needs_noise) {
 		errorstream << "register_ore: specified ore type requires valid "
 			"'noise_params' parameter" << std::endl;
 		delete ore;