static void InjectSaveHook()
{
var saveWorld = typeDef_WorldFile.GetMethod("saveWorld", MethodFlags.Public | MethodFlags.Static, typeSys.Boolean, typeSys.Boolean);
var swb = saveWorld.Body;
var swbproc = swb.GetILProcessor();
MethodDefinition invokeSaveWorld;
var saveWorldDel = context.CreateDelegate("Terraria.PrismInjections", "WorldFile_OnSaveWorldDel", typeSys.Void, out invokeSaveWorld, typeSys.Boolean);
var onSaveWorld = new FieldDefinition("P_OnSaveWorld", FieldAttributes.Public | FieldAttributes.Static, saveWorldDel);
typeDef_WorldFile.Fields.Add(onSaveWorld);
OpCode[] toFind =
{
OpCodes.Ldloc_S,
OpCodes.Call,
OpCodes.Leave_S
};
Instruction[] toInject =
{
Instruction.Create(OpCodes.Ldsfld, onSaveWorld),
Instruction.Create(OpCodes.Ldarg_0),
Instruction.Create(OpCodes.Callvirt, invokeSaveWorld)
};
var instr = swb.FindInstrSeqStart(toFind).Next.Next;
for (int i = 0; i < toInject.Length; i++)
{
swbproc.InsertBefore(instr, toInject[i]);
}
}
static void InsertSaveLoadHooks()
{
TypeDefinition typeDef_PlayerFileData = memRes.GetType("Terraria.IO.PlayerFileData");
#region SavePlayer
{
var savePlayer = typeDef_Player.GetMethod("SavePlayer");
MethodDefinition invokeSavePlayer;
var onSavePlayerDel = context.CreateDelegate("Terraria.PrismInjections", "Player_OnSavePlayerDel", typeSys.Void, out invokeSavePlayer, typeDef_PlayerFileData);
var onSavePlayer = new FieldDefinition("P_OnSavePlayer", FieldAttributes.Public | FieldAttributes.Static, onSavePlayerDel);
typeDef_Player.Fields.Add(onSavePlayer);
var spb = savePlayer.Body;
var spproc = spb.GetILProcessor();
spproc.Remove(spb.Instructions.Last());
spproc.Emit(OpCodes.Ldsfld, onSavePlayer);
spproc.Emit(OpCodes.Ldarg_0);
spproc.Emit(OpCodes.Callvirt, invokeSavePlayer);
spproc.Emit(OpCodes.Ret);
}
#endregion
#region LoadPlayer
{
// Insert load hook near end of LoadPlayer
var loadPlayer = typeDef_Player.GetMethod("LoadPlayer", MethodFlags.Public | MethodFlags.Static, typeSys.String, typeSys.Boolean);
MethodDefinition invokeLoadPlayer;
var onLoadPlayerDel = context.CreateDelegate("Terraria.PrismInjections", "Player_OnLoadPlayerDel", typeSys.Void, out invokeLoadPlayer, typeDef_Player, typeSys.String);
var onLoadPlayer = new FieldDefinition("P_OnLoadPlayer", FieldAttributes.Public | FieldAttributes.Static, onLoadPlayerDel);
typeDef_Player.Fields.Add(onLoadPlayer);
var lpb = loadPlayer.Body;
var lpproc = lpb.GetILProcessor();
var ldPlayerLoc = TerrariaPatcher.Platform == Platform.Windows ? OpCodes.Ldloc_1 : OpCodes.Ldloc_2;
// player.skinVariant = (int)MathHelper.Clamp((float)player.skinVariant, 0f, 7f);
OpCode[] toFind =
{
ldPlayerLoc, // player (for the stfld instruction at the end)
ldPlayerLoc,
OpCodes.Ldfld, // player.skinVariant
OpCodes.Conv_R4, // (float)^
OpCodes.Ldc_R4,
OpCodes.Ldc_R4,
OpCodes.Call, // MathHelper.Clamp(^, 0f, 7f)
OpCodes.Conv_I4, // (int)^
OpCodes.Stfld // ^^.skinVariant = ^
};
Instruction[] toInject =
{
Instruction.Create(OpCodes.Ldsfld, onLoadPlayer),
Instruction.Create(OpCodes.Ldloc_1),
Instruction.Create(OpCodes.Ldarg_0),
Instruction.Create(OpCodes.Callvirt, invokeLoadPlayer)
};
var first = lpb.FindInstrSeqStart(toFind);
foreach (var i in toInject)
{
lpproc.InsertBefore(first, i);
}
// rewire the if before it to end at the injected instructions instead of the code we looked for
foreach (var i in lpb.Instructions)
{
if (i.Operand == first)
{
i.Operand = toInject[0];
}
}
// not rewiring the if will lead to invalid IL, because the target instruction won't exist (because we're removing it here)
lpproc.RemoveInstructions(first, toFind.Length); // remove the limitation while we're at it
}
#endregion
}
static void ReplaceSoundHitCalls()
{
#region ReflectProjectile
{ // introduce a new scope level here so variables can be reused in the StrikeNPC part
var reflectProjectile = typeDef_NPC.GetMethod("ReflectProjectile");
// first statement in the method is "Main.PlaySound(...);"
// instruction after the "call Main.PlaySound" is a ldc.i4.0 (first one in the method)
MethodDefinition invokeSoundHit;
var onReflProjSoundHit = context.CreateDelegate("Terraria.PrismInjections", "NPC_ReflectProjectile_PlaySoundHitDel", typeSys.Void, out invokeSoundHit, typeDef_NPC, typeSys.Int32);
var reflectProjectile_PlaySoundHit = new FieldDefinition("P_ReflectProjectile_PlaySoundHit", FieldAttributes.Public | FieldAttributes.Static, onReflProjSoundHit);
typeDef_NPC.Fields.Add(reflectProjectile_PlaySoundHit);
var rpproc = reflectProjectile.Body.GetILProcessor();
rpproc.RemoveInstructions(reflectProjectile.Body.Instructions.TakeWhile(i => i.OpCode.Code != Code.Ldc_I4_0).ToArray() /* must enumerate this already, invalidoperation will be thrown otherwise */);
var first = reflectProjectile.Body.Instructions[0];
rpproc.InsertBefore(first, Instruction.Create(OpCodes.Ldsfld, reflectProjectile_PlaySoundHit));
rpproc.EmitWrapperCall(invokeSoundHit, first);
}
#endregion
#region StrikeNPC
{
var strikeNpc = typeDef_NPC.GetMethod("StrikeNPC");
MethodDefinition invokeSoundHit;
var onStrikeNpcSoundHit = context.CreateDelegate("Terraria.PrismInjections", "NPC_StrikeNPC_PlaySoundHitDel", typeSys.Void, out invokeSoundHit,
typeDef_NPC, typeSys.Int32, typeSys.Single, typeSys.Int32, typeSys.Boolean, typeSys.Boolean, typeSys.Boolean);
var strikeNpc_PlaySoundHit = new FieldDefinition("P_StrikeNPC_PlaySoundHit", FieldAttributes.Public | FieldAttributes.Static, onStrikeNpcSoundHit);
typeDef_NPC.Fields.Add(strikeNpc_PlaySoundHit);
var snb = strikeNpc.Body;
var snproc = snb.GetILProcessor();
OpCode[] toRem =
{
OpCodes.Ldarg_0,
OpCodes.Ldfld, // NPC.soundHit
OpCodes.Ldc_I4_0,
OpCodes.Ble_S, // <after the call>
OpCodes.Ldc_I4_3, // soundHit ID
OpCodes.Ldarg_0,
OpCodes.Ldflda, // Entity.position
OpCodes.Ldfld, // Vector2.X
OpCodes.Conv_I4,
OpCodes.Ldarg_0,
OpCodes.Ldflda, // Entity.position
OpCodes.Ldfld, // Vector2.X
OpCodes.Conv_I4,
OpCodes.Ldarg_0,
OpCodes.Ldfld, // NPC.soundHit
OpCodes.Call // Main.PlaySound(int, int, int, int)
};
var instrs = snb.FindInstrSeqStart(toRem);
instrs = snproc.RemoveInstructions(instrs, toRem.Length);
snproc.InsertBefore(instrs, Instruction.Create(OpCodes.Ldsfld, strikeNpc_PlaySoundHit));
snproc.EmitWrapperCall(invokeSoundHit, instrs);
}
#endregion
}
/// <summary>
/// Wraps a method using a fancy delegate. Replaces all references of the method with the wrapped one and creates an "On[MethodName]" hook which passes the method's parent type followed by the type parameters of the original method.
/// </summary>
/// <param name="context">The current Cecil context.</param>
/// <param name="delegateNS">The namespace of the delegate type to create.</param>
/// <param name="delegateTypeName">The name of the delegate type to create.</param>
/// <param name="origMethod">The method to wrap.</param>
public static void Wrap(this MethodDefinition origMethod, CecilContext context, string delegateNS, string delegateTypeName, string fieldName)
{
MethodDefinition invokeDelegate;
SingletonTRArr[0] = origMethod.DeclaringType;
//If anyone knows a better way to insert one element at the beginning of an array and scoot
//all the other elements down one index then go ahead and do it lol. I dunno how2array.
var delegateArgs = (origMethod.IsStatic ? EmptyTRArr : SingletonTRArr).Concat(origMethod.Parameters.Select(p => p.ParameterType)).ToArray();
var newDelegateType = context.CreateDelegate(delegateNS, delegateTypeName, origMethod.ReturnType, out invokeDelegate, delegateArgs);
var newMethod = origMethod.ReplaceAndHook(invokeDelegate, origMethod, fieldName);
origMethod.ReplaceAllMethodRefs(newMethod, context);
}
static void AddOnUpdateKeyboardHook()
{
OpCode[] search =
{
OpCodes.Call, //IL_27a6: call valuetype [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Input.KeyboardState Microsoft.Xna.Framework.Input.Keyboard::GetState()
OpCodes.Stsfld, //IL_27ab: stsfld valuetype [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Input.KeyboardState Terraria.Main::keyState
OpCodes.Ldsfld, //IL_27b0: ldsfld bool Terraria.Main::editSign
OpCodes.Brfalse_S, //IL_27b5: brfalse.s IL_27bd
OpCodes.Ldc_I4_0, //IL_27b7: ldc.i4.0
OpCodes.Stsfld, //IL_27b8: stsfld bool Terraria.Main::chatMode
OpCodes.Ldsfld, //IL_27bd: ldsfld bool Terraria.Main::chatMode
OpCodes.Brtrue_S, //IL_27c2: brtrue.s IL_27cf
OpCodes.Ldc_I4_0, //IL_27c4: ldc.i4.0
OpCodes.Stsfld, //IL_27c5: stsfld int32 Terraria.Main::startChatLine
OpCodes.Br, //IL_27ca: br IL_2a83
OpCodes.Ldsfld, //IL_27cf: ldsfld int32 Terraria.Main::screenHeight
OpCodes.Ldc_I4_3, //IL_27d4: ldc.i4.3
OpCodes.Div, //IL_27d5: div
OpCodes.Conv_R4, //IL_27d6: conv.r4
OpCodes.Ldsfld, //IL_27d7: ldsfld class [Microsoft.Xna.Framework.Graphics]Microsoft.Xna.Framework.Graphics.SpriteFont Terraria.Main::fontMouseText
OpCodes.Ldstr, //IL_27dc: ldstr "1"
OpCodes.Callvirt, //IL_27e1: callvirt instance valuetype [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Vector2 [Microsoft.Xna.Framework.Graphics]Microsoft.Xna.Framework.Graphics.SpriteFont::MeasureString(string)
TerrariaPatcher.Platform == Platform.Windows ? OpCodes.Endfinally : OpCodes.Stloc_S,
TerrariaPatcher.Platform == Platform.Windows ? OpCodes.Endfinally : OpCodes.Ldloca_S,
OpCodes.Ldfld, //IL_27e6: ldfld float32 [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Vector2::Y
OpCodes.Div, //IL_27eb: div
OpCodes.Conv_I4, //IL_27ec: conv.i4
OpCodes.Ldc_I4_1, //IL_27ed: ldc.i4.1
OpCodes.Sub, //IL_27ee: sub
OpCodes.Stsfld, //IL_27ef: stsfld int32 Terraria.Main::showCount
OpCodes.Ldsflda, //IL_27f4: ldsflda valuetype [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Input.KeyboardState Terraria.Main::keyState
OpCodes.Ldc_I4_S, //IL_27f9: ldc.i4.s 38
OpCodes.Call, //IL_27fb: call instance bool [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Input.KeyboardState::IsKeyDown(valuetype [Microsoft.Xna.Framework]Microsoft.Xna.Framework.Input.Keys)
OpCodes.Brfalse_S, //IL_2800: brfalse.s IL_2864
};
search = search.Where(o => o.Code != Code.Endfinally).ToArray();
var mainUpdate = typeDef_Main.GetMethod("Update");
var mainUpdateBody = mainUpdate.Body;
var first = mainUpdateBody.FindInstrSeqStart(search);
if (!(first != null && (first = first.Next) != null && (first = first.Next) != null))
{
Console.Error.WriteLine("Couldn't find instructions for MainPatcher::AddOnUpdateKeyboardHook()");
}
//public virtual void P_OnUpdateInputHook() { }
MethodDefinition invokeOnUpdateKeyboardHook;
var onUpdateKeyboardDelType = context.CreateDelegate("Terraria.PrismInjections", "Main_Update_OnUpdateKeyboardDel", typeSys.Void, out invokeOnUpdateKeyboardHook, typeDef_Main, mainUpdate.Parameters[0].ParameterType /* HAH I WIN, XNA */);
var onUpdateKeyboardDelField = new FieldDefinition("P_Main_Update_OnUpdateKeyboard", FieldAttributes.Public | FieldAttributes.Static, onUpdateKeyboardDelType);
typeDef_Main.Fields.Add(onUpdateKeyboardDelField);
var mainUpdateProc = mainUpdateBody.GetILProcessor();
mainUpdateProc.InsertBefore(first, Instruction.Create(OpCodes.Ldsfld, onUpdateKeyboardDelField));
mainUpdateProc.EmitWrapperCall(invokeOnUpdateKeyboardHook, first);
//mainUpdateProc.InsertBefore(first, Instruction.Create(OpCodes.Call, invokeOnUpdateKeyboardHook));
}