From 5845da7ca9439fbfb923dce13c04c7fb745fb93e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Krzysztof=20Wi=C5=9Bniewski?= <argmaster.world@gmail.com>
Date: Sat, 22 Mar 2025 19:33:53 +0100
Subject: [PATCH] Add `/rotate` command (#1225)

* Revert "Remove rotate command"

This reverts commit 3a84e03d158e5cc038ae3e936384c348431a9ac4.

* Fix stair rotation

* Add rotate fn to Blueprint

* Apply suggestions from code review

Co-authored-by: IntegratedQuantum <43880493+IntegratedQuantum@users.noreply.github.com>

* Replace cos sin with switch

* Add angle parameter to /rotate

* Update src/blueprint.zig

* Apply review suggestions

* Fix formatting issues

* Update src/rotation.zig

---------

Co-authored-by: IntegratedQuantum <43880493+IntegratedQuantum@users.noreply.github.com>
---
 src/blueprint.zig                       | 28 +++++++++++++++++++++++++
 src/rotation.zig                        |  4 ++--
 src/server/command/_list.zig            |  1 +
 src/server/command/worldedit/rotate.zig | 28 +++++++++++++++++++++++++
 4 files changed, 59 insertions(+), 2 deletions(-)
 create mode 100644 src/server/command/worldedit/rotate.zig

diff --git a/src/blueprint.zig b/src/blueprint.zig
index 25daff04..28bcd745 100644
--- a/src/blueprint.zig
+++ b/src/blueprint.zig
@@ -10,6 +10,8 @@ const Array3D = main.utils.Array3D;
 const Block = main.blocks.Block;
 const NeverFailingAllocator = main.heap.NeverFailingAllocator;
 const User = main.server.User;
+const ServerChunk = main.chunk.ServerChunk;
+const Degrees = main.rotation.Degrees;
 
 const GameIdToBlueprintIdMapType = std.AutoHashMap(u16, u16);
 const BlockIdSizeType = u32;
@@ -36,6 +38,32 @@ pub const Blueprint = struct {
 	pub fn clone(self: *Blueprint, allocator: NeverFailingAllocator) Blueprint {
 		return .{.blocks = self.blocks.clone(allocator)};
 	}
+	pub fn rotateZ(self: Blueprint, allocator: NeverFailingAllocator, angle: Degrees) Blueprint {
+		var new = Blueprint{
+			.blocks = switch(angle) {
+				.@"0", .@"180" => .init(allocator, self.blocks.width, self.blocks.depth, self.blocks.height),
+				.@"90", .@"270" => .init(allocator, self.blocks.depth, self.blocks.width, self.blocks.height),
+			},
+		};
+
+		for(0..self.blocks.width) |xOld| {
+			for(0..self.blocks.depth) |yOld| {
+				const xNew, const yNew = switch(angle) {
+					.@"0" => .{xOld, yOld},
+					.@"90" => .{new.blocks.width - yOld - 1, xOld},
+					.@"180" => .{new.blocks.width - xOld - 1, new.blocks.depth - yOld - 1},
+					.@"270" => .{yOld, new.blocks.depth - xOld - 1},
+				};
+
+				for(0..self.blocks.height) |z| {
+					const block = self.blocks.get(xOld, yOld, z);
+					new.blocks.set(xNew, yNew, z, block.rotateZ(angle));
+				}
+			}
+		}
+		return new;
+	}
+
 	const CaptureResult = union(enum) {
 		success: Blueprint,
 		failure: struct {pos: Vec3i, message: []const u8},
diff --git a/src/rotation.zig b/src/rotation.zig
index e1958cec..acafccc2 100644
--- a/src/rotation.zig
+++ b/src/rotation.zig
@@ -806,7 +806,7 @@ pub const RotationModes = struct {
 			comptime var rotationTable: [4][256]u8 = undefined;
 			comptime for(0..4) |a| {
 				for(0..256) |old| {
-					var new: u8 = 0;
+					var new: u8 = 0b11_11_11_11;
 
 					for(0..2) |i| for(0..2) |j| for(0..2) |k| {
 						const sin: f32 = @sin((std.math.pi/2.0)*@as(f32, @floatFromInt(a)));
@@ -819,7 +819,7 @@ pub const RotationModes = struct {
 						const rY = @intFromBool(x*sin + y*cos > 0);
 
 						if(hasSubBlock(@intCast(old), @intCast(i), @intCast(j), @intCast(k))) {
-							new |= subBlockMask(rX, rY, @intCast(k));
+							new &= ~subBlockMask(rX, rY, @intCast(k));
 						}
 					};
 					rotationTable[a][old] = new;
diff --git a/src/server/command/_list.zig b/src/server/command/_list.zig
index afee7f90..9b5646ca 100644
--- a/src/server/command/_list.zig
+++ b/src/server/command/_list.zig
@@ -12,3 +12,4 @@ pub const deselect = @import("worldedit/deselect.zig");
 pub const copy = @import("worldedit/copy.zig");
 pub const paste = @import("worldedit/paste.zig");
 pub const blueprint = @import("worldedit/blueprint.zig");
+pub const rotate = @import("worldedit/rotate.zig");
diff --git a/src/server/command/worldedit/rotate.zig b/src/server/command/worldedit/rotate.zig
new file mode 100644
index 00000000..f508b57a
--- /dev/null
+++ b/src/server/command/worldedit/rotate.zig
@@ -0,0 +1,28 @@
+const std = @import("std");
+
+const main = @import("root");
+const User = main.server.User;
+const Degrees = main.rotation.Degrees;
+
+pub const description = "rotate clipboard content around Z axis counterclockwise.";
+pub const usage =
+	\\/rotate
+	\\/rotate <0/90/180/270>
+;
+
+pub fn execute(args: []const u8, source: *User) void {
+	var angle: Degrees = .@"90";
+	if(args.len != 0) {
+		angle = std.meta.stringToEnum(Degrees, args) orelse {
+			source.sendMessage("#ff0000Error: Invalid angle '{s}'. Use 0, 90, 180 or 270.", .{args});
+			return;
+		};
+	}
+	if(source.worldEditData.clipboard == null) {
+		source.sendMessage("#ff0000Error: No clipboard content to rotate.", .{});
+		return;
+	}
+	const current = source.worldEditData.clipboard.?;
+	defer current.deinit(main.globalAllocator);
+	source.worldEditData.clipboard = current.rotateZ(main.globalAllocator, angle);
+}