Resolve some quirks with (wield) item meshes for nodes (#15654)

src/client/content_mapblock.cpp

@@ -1781,11 +1781,3 @@ void MapblockMeshGenerator::generate()
 		drawNode();
 	}
 }
-
-void MapblockMeshGenerator::renderSingle(content_t node, u8 param2)
-{
-	cur_node.p = {0, 0, 0};
-	cur_node.n = MapNode(node, 0xff, param2);
-	cur_node.f = &nodedef->get(cur_node.n);
-	drawNode();
-}

src/client/content_mapblock.h

@@ -47,7 +47,6 @@ class MapblockMeshGenerator
 public:
 	MapblockMeshGenerator(MeshMakeData *input, MeshCollector *output);
 	void generate();
-	void renderSingle(content_t node, u8 param2 = 0x00);
 
 private:
 	MeshMakeData *const data;

src/client/mapblock_mesh.cpp

@@ -31,7 +31,9 @@ MeshMakeData::MeshMakeData(const NodeDefManager *ndef,
 	m_side_length(side_length),
 	m_mesh_grid(mesh_grid),
 	m_nodedef(ndef)
-{}
+{
+	assert(m_side_length > 0);
+}
 
 void MeshMakeData::fillBlockDataBegin(const v3s16 &blockpos)
 {
@@ -55,6 +57,24 @@ void MeshMakeData::fillBlockData(const v3s16 &bp, MapNode *data)
 	m_vmanip.copyFrom(data, data_area, v3s16(0,0,0), blockpos_nodes, data_size);
 }
 
+void MeshMakeData::fillSingleNode(MapNode data, MapNode padding)
+{
+	m_blockpos = {0, 0, 0};
+
+	m_vmanip.clear();
+	// area around 0,0,0 so that this positon has neighbors
+	const s16 sz = 3;
+	m_vmanip.addArea({v3s16(-sz), v3s16(sz)});
+
+	u32 count = m_vmanip.m_area.getVolume();
+	for (u32 i = 0; i < count; i++) {
+		m_vmanip.m_data[i] = padding;
+		m_vmanip.m_flags[i] &= ~VOXELFLAG_NO_DATA;
+	}
+
+	m_vmanip.setNodeNoEmerge({0, 0, 0}, data);
+}
+
 void MeshMakeData::setCrack(int crack_level, v3s16 crack_pos)
 {
 	if (crack_level >= 0)
@@ -628,6 +648,7 @@ MapBlockMesh::MapBlockMesh(Client *client, MeshMakeData *data, v3s16 camera_offs
 	MeshCollector collector(m_bounding_sphere_center, offset);
 
 	{
+		// Generate everything
 		MapblockMeshGenerator(data, &collector).generate();
 	}
 
@@ -940,21 +961,22 @@ video::SColor encode_light(u16 light, u8 emissive_light)
 
 u8 get_solid_sides(MeshMakeData *data)
 {
-	std::unordered_map<v3s16, u8> results;
 	v3s16 blockpos_nodes = data->m_blockpos * MAP_BLOCKSIZE;
 	const NodeDefManager *ndef = data->m_nodedef;
 
-	u8 result = 0x3F; // all sides solid;
+	const u16 side = data->m_side_length;
+	assert(data->m_vmanip.m_area.contains(blockpos_nodes + v3s16(side - 1)));
 
-	for (s16 i = 0; i < data->m_side_length && result != 0; i++)
-	for (s16 j = 0; j < data->m_side_length && result != 0; j++) {
+	u8 result = 0x3F; // all sides solid
+	for (s16 i = 0; i < side && result != 0; i++)
+	for (s16 j = 0; j < side && result != 0; j++) {
 		v3s16 positions[6] = {
 			v3s16(0, i, j),
-			v3s16(data->m_side_length - 1, i, j),
+			v3s16(side - 1, i, j),
 			v3s16(i, 0, j),
-			v3s16(i, data->m_side_length - 1, j),
+			v3s16(i, side - 1, j),
 			v3s16(i, j, 0),
-			v3s16(i, j, data->m_side_length - 1)
+			v3s16(i, j, side - 1)
 		};
 
 		for (u8 k = 0; k < 6; k++) {

src/client/mapblock_mesh.h

@@ -62,6 +62,11 @@ struct MeshMakeData
 	void fillBlockDataBegin(const v3s16 &blockpos);
 	void fillBlockData(const v3s16 &bp, MapNode *data);
 
+	/*
+		Prepare block data for rendering a single node located at (0,0,0).
+	*/
+	void fillSingleNode(MapNode data, MapNode padding = MapNode(CONTENT_AIR));
+
 	/*
 		Set the (node) position of a crack
 	*/