# New Gump API
We are pleased to release a new API that is faster, allocates nearly zero memory, and still feels very similar to the original API. The API is broken into 3 types of gumps, dynamic, static with placeholders, and static without placeholders.
### Dynamic Gumps
These gumps will inherit `DynamicGump` and are meant for gumps that have a dynamic layout. This includes specifying dynamic arguments to HtmlLocalized entries.
## Static Gumps
Static gumps are those where the function to the build the layout is called only once and cached forever. They can optionally have placeholders. These placeholders allow the developer to specify the string values later, dynamically in a `BuildStrings` method on the gump. If a gump does not have any placeholders, the string entries will also be cached forever.
## Benchmarks
To make sure we were going in the right direction and not wasting time, we took copious benchmarks. Here are the final benchmarks for a really simple gump.
Note:
* The majority of creating a gump is compressing the layout and the strings. Compressing each section takes ~6,000ns (12us total).
```cs
| Method | Mean | Error | StdDev | Median | Ratio | RatioSD | Gen0 | Allocated | Alloc Ratio |
|------------------------------- |-------------:|-------------:|-------------:|-------------:|------:|--------:|-------:|----------:|------------:|
| OldGump | 13,308.29 ns | 1,059.695 ns | 1,883.608 ns | 14,330.72 ns | 1.000 | 0.00 | 0.1526 | 2400 B | 1.00 |
| DynamicLayoutGump | 13,357.86 ns | 129.144 ns | 226.185 ns | 13,323.60 ns | 1.029 | 0.17 | - | 48 B | 0.02 |
| StaticLayoutDynamicStringsGump | 6,653.10 ns | 81.815 ns | 143.292 ns | 6,617.45 ns | 0.514 | 0.09 | - | 40 B | 0.02 |
| StaticLayoutGump | 86.33 ns | 0.760 ns | 1.350 ns | 86.07 ns | 0.007 | 0.00 | 0.0020 | 32 B | 0.01 |
```
# Non-Breaking Changes
* All gump components in the core have been moved to `Gumps/Legacy`.
* All legacy gumps will still inherit `Gump`, which now inherits `BaseGump`
# Special Thanks
Thank you to @stefanomerotta for considerable contributions/benchmarking/testing to make this effort a reality! We collectively went through over 10 iterations, but it is finally ready.
### Summary
* Removes old gump packet support
* Removes support for v4 clients
* Removes `Unpack` flag and assumes it is always true.
* Removes StringToBuffer since this is built into .NET now.
> [!Note]
> View the file changes with white space off: https://github.com/modernuo/ModernUO/pull/1739/files?diff=split&w=1
### Summary
* Fixes spawner timer deserialization
* Adds a check for a null timer and allows the timer to get recreated
* Adds PotionKeg reverse lookup
* Heavily optimizes decimal serialize/deserialize
### Summary
- Fixes `[AdvancedSearch` being accessible by players 😱
- Adds `[GenCommands` to generate the same commands html page on https://muo.gg/commands.
- Fixes `[helpinfo` so all commands properly show up!
> [!WARNING]
> ### Developer Warning:
> Commands must now be registered in the `Configure` bootup phase.
> If a command is not registered early enough, it may not be available to systems like [helpinfo
> that cache their information.
> [!NOTE]
> ### Developer Note:
> Various commands related to generating content have been changed to _Developer_ and above access level.
### Screenshots
<img width="673" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/b105b5c9-5eb4-4ace-93ff-1bfb31e7132f">
<img width="547" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/e97487e8-47a5-4aa7-89cc-9fe3deda584d">
## Breaking Changes
* The Firewall and IP Limiter have been rewritten. Please read the notes carefully!
* `TcpServer.Instances` moved back to `NetState.Instances` - sorry - it was stupid to move it to begin with.
> [!Note]
> Sockets that fail the IP Limiter or Firewall will be immediately and forcibly disconnected.
> This means they will be stuck at "Verifying account..." if it was a real client.
### Summary
- Removes firewall wildcard support.
- Removes `AccessRestrictions`.
- Moves Firewall/IPLimiter to the core.
- Moves `TcpServer` to its own thread.
- Removes the `SocketConnect` and `SocketDisconnect` event sinks.
- Moves `Instances` back to `NetState.Instances`.
- Fixes a long standing bug with bad handling of duplicate listener addresses.
#### Firewall
The firewall has been completely rewritten. There is now an "Admin Firewall" which saves to the config file. Secondarily, there is an internal firewall used exclusively by the TcpServer while processing sockets. The Admin firewall mirrors it's additions/deletions to the internal firewall by adding requests to a queue.
> [!IMPORTANT]
> **Wildcard firewall entries, such as `X`, `*`, `?` are not allowed.**
> **Ranges in between IP classes or sextets are not allowed.**
> **Please make sure to use one of the following:**
> * IP Address - `192.168.1.1`
> * CIDR - `192.168.1.0/24`
> * Range - `192.168.1.1-192.168.1.100`
#### IP Limiter
The IP Limiter has been completely rewritten. The available configurations are:
```json
"ipLimiter.enable": "True",
"ipLimiter.maxConnectionsPerIP": 10,
"ipLimiter.clearConnectionAttemptsDuration": "00:00:00:10",
"ipLimiter.clearThrottledDuration": "00:00:02:00",
```
The IP Limiter is set up to prevent spamming connections from the same IP. Every time an IP connects, it is added to a connection list. After 10 attempts, the IP is added to the throttle list. To keep the system fast, the connection list is entirely wiped every 10 seconds, and the throttle list is entirely wiped every 2 minutes.
### Summary
- Removes old death packet that isn't used. Doubtful this causes issues with clients that are v4+.
- Removes duplicate incoming packets. Again, probably to fix some old client issues, doubtful it affects clients v4+.
- Fixes setting serials and entities in props/commands. Note: Disabled setting `Parent` since the new sector code has issues. We shouldn't rely on it anyway!
- Reverts a recent change to healthbars that should not have been made. Oops!
### Summary
TLDR - .NET Framework rounded TimeSpan (and some DateTime) methods to the nearest millisecond. This was actually _expected_ accidentally for parts of RunUO.
We are aiming to fix this and clean up some other bad assumptions.
Closes#1604
### Summary
.NET 8 supports Xoroshiro 256** off the shelf and added Shuffle. Switching to that implementation.
### Developer Notes
* Removed many convenience methods that weren't used.
### Summary
The BitArray class will be optimized over the next several years for various platforms/hardware and maintaining a duplicate for serialization is not practical. Removing the custom implementation. Recommend against using BitArray for serialization unless it is absolutely necessary.
### Summary
Modifying a ValueLinkList using one of the methods will bump the "version". This field is used by iterators (foreach loops) to determine if the link list was modified while iterating. The sector.Items (and in the future other lists), will no longer be safe to modify while iterating. The server will _CRASH_ if the ValueLinkList is modified.
Thanks to @stefanomerotta for help!
### Screenshots
<img width="588" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/83ee0b6e-ff4f-4768-9e29-84456e04b1ec">
### Summary
- Fixes usernames not being `Intern`ed
- Reverts methods related to getting accounts from returning `Account` to `IAccount`.
- Makes `IAccount` also `ISerializable`
- Adds `IGenericReader.ReadAccount()` and `IGenericWriter.Write(IAccount)` -> The read method supports the original serialization of username, and using `IAccount.Serial`. The write method only serializes the `Serial`.
- Exposes `ReadStringRaw()` to allow some advanced scenarios.
## Breaking Changes
Incoming packet registration signature has changed to:
```cs
delegate* void OnReceiveCallback(NetState state, SpanReader reader, int packetLength);
IncomingPackets.Register(int packetID, int length, bool ingame, OnReceiveCallback onReceive);
```
For example, an incoming packet handler signature would now look like this:
```cs
public static void SomeIncomingPacket(NetState state, SpanReader reader, int packetLength)
{
// Parse the data
}
```
## Summary
Updates the network Pipe class to use a mirrored memory technique. This technique involves mapping the same physical memory to two contiguous virtual memory spaces so the byte buffer appears duplicated. This allows writing to a double-sized array to wrap around without the need for the `CircularBuffer` classes.
In practice this allows us to use `Span<byte>` as if the buffer was a regular array.
### Bug Fixes
- [X] Fixes bad fixed length string parsing
### Summary
Container enumeration is in dire need of optimization. Thanks to @stefanomerotta for initiating this work with PR #1443. This PR handles a small part of what Stefan started. Also included are some bug fixes.
### Method Signatures
```cs
// Use with foreach without moving/deleting items
FindItemsByTypeEnumerator<T> FindItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use with foreach when moving/deleting items
QueuedItemsEnumerator<T> EnumerateItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use when iterating multiple times or queuing
PooledRefQueue<T> QueueItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use when iterating multiples times or manipulating elements without traversing
PooledRefList<T> ListItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
```
* `FindItemsByType<T>` has changed from returning `List<T>` to `FindItemsByTypeEnumerator<T>` - This method is not safe to use in situations where an item may get consumed, deleted, or moved.
* `EnumerateItemsByType<T>` was added as a safe way to iterate and manipulate items.
* **Note**: EnumerateItemsByType will _completely traverse the container_ before iteration starts because it uses `QueueItemsByType` under the hood.
* `QueueItemsByType<T>` and `ListItemsByType<T>` was added to return a queue or list of items to iterate multiple times and manipulate the items. This isn't the most efficient since it uses a predicate and can result in 2 or 3 total iterations unnecessarily.
### Bug Fixes
- [X] Fishing had an error in the random check that may have caused slight bias.
### Summary
- Removes Fastwalk system
- Removed the following settings:
- `movement.enableFastWalkPrevention`
- `movement.fastwalkExemptionLevel`
- Adds movement throttle system.
- Adds the following settings:
- `movement.throttleReset` - Default value is `1000` (1 second).
- `movement.throttleThreshold` - Default value is `400` (400ms).
### Movement Throttling
This new system will trigger if a player requests 400ms (configurable) worth of movements quicker than wall clock time. When this happens, the player is throttled (all incoming packets to the server are halted) until wall clock time catches up with the requests. Upon each throttle, the player receives enough credit to handle up to 400ms of "lag" as a grace/catch-up.
### Developer Notes
We use two throttle queues to prevent an infinite loop.
### Summary
- Adds KR/EC client versions to ClientVersion
- Adds distinction for enhanced versions in the page queue
- Adds KR Expansion flags
- Adds ProtocolChange enum support
- Adds missing Moongate checks for TerMur
- Adds better message for why a client version is not supported, and which ones are supported.
