Add a hanging plant rotation mode (#1742)

Mostly fixes #1030 
It is currently not possible to make the whole vine break when the
support is removed as far as I can tell, but it works well otherwise.

assets/cubyz/blocks/vine/_defaults.zig.zon

@@ -0,0 +1,17 @@
+.{
+	.tags = .{.cuttable},
+	.blockHealth = 0.3,
+	.drops = .{
+		.{.items = .{.auto}},
+	},
+	.degradable = true,
+	.viewThrough = true,
+	.absorbedLight = 0x000000,
+	.collide = false,
+	.model = {
+		.top = "cubyz:cross",
+		.bottom = "cubyz:cross_with_texture_1",
+	}
+	.rotation = "cubyz:hanging",
+	.lodReplacement = "cubyz:air",
+}

assets/cubyz/blocks/vine/mahogany.zig.zon

@@ -0,0 +1,7 @@
+.{
+	.texture0 = "cubyz:vine/mahogany/top",
+	.texture1 = "cubyz:vine/mahogany/bottom",
+	.item = .{
+		.texture = "vine/mahogany.png",
+	},
+}

assets/cubyz/blocks/vine/willow.zig.zon

@@ -0,0 +1,7 @@
+.{
+	.texture0 = "cubyz:vine/willow/top",
+	.texture1 = "cubyz:vine/willow/bottom",
+	.item = .{
+		.texture = "vine/willow.png",
+	},
+}

assets/cubyz/models/cross_with_texture_1.obj

@@ -0,0 +1,20 @@
+v 1 1 0
+v 1 1 1
+v 0 0 0
+v 0 0 1
+v 0 1 0
+v 0 1 1
+v 1 0 0
+v 1 0 1
+vt 0.25 0
+vt 0.25 0.25
+vt 0.5 0
+vt 0.5 0.25
+vn -0.70703125 0.70703125 0
+vn 0.70703125 -0.70703125 0
+vn -0.70703125 -0.70703125 0
+vn 0.70703125 0.70703125 0
+f 2/2/1 1/1/1 3/3/1 4/4/1
+f 4/2/2 3/1/2 1/3/2 2/4/2
+f 6/2/3 5/1/3 7/3/3 8/4/3
+f 8/2/4 7/1/4 5/3/4 6/4/4

mods/cubyz/rotation/hanging.zig

@@ -0,0 +1,59 @@
+const std = @import("std");
+
+const main = @import("main");
+const blocks = main.blocks;
+const Block = blocks.Block;
+const Neighbor = main.chunk.Neighbor;
+const ModelIndex = main.models.ModelIndex;
+const rotation = main.rotation;
+const RotationMode = rotation.RotationMode;
+const vec = main.vec;
+const Vec3f = vec.Vec3f;
+const Vec3i = vec.Vec3i;
+const ZonElement = main.ZonElement;
+
+pub const dependsOnNeighbors = true;
+
+fn transform(_: *main.models.QuadInfo) void {}
+
+pub fn init() void {}
+pub fn deinit() void {}
+pub fn reset() void {}
+
+pub fn createBlockModel(_: Block, _: *u16, zon: ZonElement) ModelIndex {
+	const topModelIndex = main.models.getModelIndex(zon.get([]const u8, "top", "cubyz:cube"));
+	const bottomModelIndex = main.models.getModelIndex(zon.get([]const u8, "bottom", "cubyz:cube"));
+
+	const modelIndex = topModelIndex.model().transformModel(transform, .{});
+	_ = bottomModelIndex.model().transformModel(transform, .{});
+	return modelIndex;
+}
+
+pub fn model(block: Block) ModelIndex {
+	return blocks.meshes.modelIndexStart(block).add(block.data%2);
+}
+
+pub fn generateData(_: *main.game.World, _: Vec3i, _: Vec3f, _: Vec3f, _: Vec3i, neighbor: ?Neighbor, currentData: *Block, neighborBlock: Block, blockPlacing: bool) bool {
+	const sameBlock = neighborBlock.typ == currentData.typ;
+	if(blockPlacing) {
+		if(neighbor != Neighbor.dirUp) return false;
+		if(!sameBlock) {
+			const neighborModel = neighborBlock.mode().model(neighborBlock).model();
+			const support = !neighborBlock.replacable() and neighborModel.neighborFacingQuads[Neighbor.dirDown.toInt()].len != 0;
+			if(!support) return false;
+		}
+		currentData.data = 1;
+		return true;
+	}
+	return false;
+}
+
+pub fn updateData(block: *Block, neighbor: Neighbor, neighborBlock: Block) bool {
+	if(neighbor != .dirDown) return false;
+
+	const newData: u16 = if(neighborBlock.typ == block.typ) 0 else 1;
+
+	if(newData == block.data) return false;
+	block.data = newData;
+	return true;
+}