fix(particlesys): Decouple creation of particle systems from game logic

GeneralsMD/Code/GameEngine/Include/Common/Geometry.h

@@ -171,8 +171,8 @@ class GeometryInfo : public Snapshot
 	/// get the 2d bounding box
 	void get2DBounds(const Coord3D& geomCenter, Real angle, Region2D& bounds	) const;
 
-	/// note that the pt is generated using game logic random, not game client random!
-	void makeRandomOffsetWithinFootprint(Coord3D& pt) const;
+	void makeGameLogicRandomOffsetWithinFootprint(Coord3D& pt) const;
+	void makeGameClientRandomOffsetWithinFootprint(Coord3D& pt) const;
 	void makeRandomOffsetOnPerimeter(Coord3D& pt) const; //Chooses a random point on the extent border.
 
 	void clipPointToFootprint(const Coord3D& geomCenter, Coord3D& ptToClip) const;

GeneralsMD/Code/GameEngine/Source/Common/System/Geometry.cpp

@@ -376,28 +376,37 @@ Bool GeometryInfo::isPointInFootprint(const Coord3D& geomCenter, const Coord3D&
 }
 
 //=============================================================================
-void GeometryInfo::makeRandomOffsetWithinFootprint(Coord3D& pt) const
+static void makeRandomOffsetWithinFootprint(
+	Real (*randomReal)(Real lo, Real hi),
+	GeometryType type,
+	Real majorRadius,
+	Real minorRadius,
+	Real boundingCircleRadius,
+	Coord3D& pt)
 {
-	switch(m_type)
+#if 1
+	(void)boundingCircleRadius;
+#endif
+	switch(type)
 	{
 		case GEOMETRY_SPHERE:
 		case GEOMETRY_CYLINDER:
 		{
 #if 1
 			// this is a better technique than the more obvious radius-and-angle
 			// one, below, because the latter tends to clump more towards the center.
-			Real maxDistSqr = sqr(m_majorRadius);
+			Real maxDistSqr = sqr(majorRadius);
 			Real distSqr;
 			do
 			{
-				pt.x = GameLogicRandomValueReal(-m_majorRadius, m_majorRadius);
-				pt.y = GameLogicRandomValueReal(-m_majorRadius, m_majorRadius);
+				pt.x = randomReal(-majorRadius, majorRadius);
+				pt.y = randomReal(-majorRadius, majorRadius);
 				pt.z = 0.0f;
 				distSqr = sqr(pt.x) + sqr(pt.y);
 			} while (distSqr > maxDistSqr);
 #else
-			Real radius = GameLogicRandomValueReal(0.0f, m_boundingCircleRadius);
-			Real angle = GameLogicRandomValueReal(-PI, PI);
+			Real radius = randomReal(0.0f, boundingCircleRadius);
+			Real angle = randomReal(-PI, PI);
 			pt.x = radius * Cos(angle);
 			pt.y = radius * Sin(angle);
 			pt.z = 0.0f;
@@ -407,14 +416,34 @@ void GeometryInfo::makeRandomOffsetWithinFootprint(Coord3D& pt) const
 
 		case GEOMETRY_BOX:
 		{
-			pt.x = GameLogicRandomValueReal(-m_majorRadius, m_majorRadius);
-			pt.y = GameLogicRandomValueReal(-m_minorRadius, m_minorRadius);
+			pt.x = randomReal(-majorRadius, majorRadius);
+			pt.y = randomReal(-minorRadius, minorRadius);
 			pt.z = 0.0f;
 			break;
 		}
 	};
 }
 
+static Real GameLogicGeometryRandomReal(Real lo, Real hi)
+{
+	return GameLogicRandomValueReal(lo, hi);
+}
+
+static Real GameClientGeometryRandomReal(Real lo, Real hi)
+{
+	return GameClientRandomValueReal(lo, hi);
+}
+
+void GeometryInfo::makeGameLogicRandomOffsetWithinFootprint(Coord3D& pt) const
+{
+	makeRandomOffsetWithinFootprint(GameLogicGeometryRandomReal, m_type, m_majorRadius, m_minorRadius, m_boundingCircleRadius, pt);
+}
+
+void GeometryInfo::makeGameClientRandomOffsetWithinFootprint(Coord3D& pt) const
+{
+	makeRandomOffsetWithinFootprint(GameClientGeometryRandomReal, m_type, m_majorRadius, m_minorRadius, m_boundingCircleRadius, pt);
+}
+
 //=============================================================================
 void GeometryInfo::makeRandomOffsetOnPerimeter(Coord3D& pt) const
 {

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Behavior/GenerateMinefieldBehavior.cpp

@@ -350,7 +350,7 @@ void GenerateMinefieldBehavior::placeMinesInFootprint(const GeometryInfo& geom,
 		Int maxRetry = 100;
 		do
 		{
-			geom.makeRandomOffsetWithinFootprint(pt);
+			geom.makeGameLogicRandomOffsetWithinFootprint(pt);
 			pt.x += target->x;
 			pt.y += target->y;
 			pt.z += target->z;

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Damage/TransitionDamageFX.cpp

@@ -253,7 +253,7 @@ void TransitionDamageFX::onDelete()
 /** Given an FXLoc info struct, return the effect position that we are supposed to use.
 	* The position is local to to the object */
 //-------------------------------------------------------------------------------------------------
-static Coord3D getLocalEffectPos( const FXLocInfo *locInfo, Drawable *draw )
+static Coord3D getLocalEffectPos( const FXLocInfo *locInfo, Drawable *draw, Bool useGameClientRandom = FALSE )
 {
 
 	DEBUG_ASSERTCRASH( locInfo, ("getLocalEffectPos: locInfo is null") );
@@ -290,7 +290,7 @@ static Coord3D getLocalEffectPos( const FXLocInfo *locInfo, Drawable *draw )
 				return locInfo->loc;
 
 			// pick one of the bone positions
-			Int pick = GameLogicRandomValue( 0, boneCount - 1 );
+			Int pick = useGameClientRandom ? GameClientRandomValue( 0, boneCount - 1 ) : GameLogicRandomValue( 0, boneCount - 1 );
 			return positions[ pick ];
 
 		}
@@ -394,7 +394,7 @@ void TransitionDamageFX::onBodyDamageStateChange( const DamageInfo* damageInfo,
 					{
 
 						// get the what is the position we're going to played the effect at
-						pos = getLocalEffectPos( &modData->m_particleSystem[ newState ][ i ].locInfo, draw );
+						pos = getLocalEffectPos( &modData->m_particleSystem[ newState ][ i ].locInfo, draw, TRUE );
 
 						//
 						// set position on system given any bone position provided, the bone position is
@@ -412,10 +412,29 @@ void TransitionDamageFX::onBodyDamageStateChange( const DamageInfo* damageInfo,
 
 					}
 
+#if RETAIL_COMPATIBLE_CRC
+					// TheSuperHackers @fix stephanmeesters 18/05/2026 Fix issue where the creation of a certain particle system
+					// would influence game logic CRC due to the incorrect usage of game logic RNG. This code block is required to
+					// forward the game logic RNG and keep things consistent.
+					if ( pSystem )
+					{
+						const FXLocInfo* locInfo = &modData->m_particleSystem[newState][i].locInfo;
+						if( locInfo->locType == FX_DAMAGE_LOC_TYPE_BONE && locInfo->randomBone && draw )
+						{
+							const Int MAX_BONES = 32;
+							Coord3D positions[ MAX_BONES ];
+							Int boneCount = draw->getPristineBonePositions( locInfo->boneName.str(), 1, positions, nullptr, MAX_BONES );
+							if( boneCount > 0 )
+							{
+								static_cast<void>(GameLogicRandomValue( 0, boneCount - 1 ));
+							}
+						}
+					}
+#endif
+
 				}
 
 			}
-
 		}
 
 	}

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Update/EMPUpdate.cpp

@@ -310,8 +310,8 @@ void EMPUpdate::doDisableAttack()
 						if (sys)
 						{
 							Coord3D offs = {0,0,0};
-							curVictim->getGeometryInfo().makeRandomOffsetWithinFootprint( offs );
-							offs.z = GameLogicRandomValue(3, victimHeight);
+							curVictim->getGeometryInfo().makeGameClientRandomOffsetWithinFootprint( offs );
+							offs.z = GameClientRandomValue(3, victimHeight);
 
 							//This puts all the sparks within a quadrahemicycloid (rectangular dome) volume
 							//The same shape as a four cornered camping dome tent, for those with less Greek
@@ -328,12 +328,25 @@ void EMPUpdate::doDisableAttack()
 							sys->attachToObject(curVictim);
 							sys->setPosition( &offs );
 							sys->setSystemLifetime(MAX(0, data->m_disabledDuration - 30));
-							sys->setInitialDelay(GameLogicRandomValue(1,100));
+							sys->setInitialDelay(GameClientRandomValue(1,100));
 						}
+
+#if RETAIL_COMPATIBLE_CRC
+						// TheSuperHackers @fix stephanmeesters 18/05/2026 Fix issue where the creation of a certain particle system
+						// would influence game logic CRC due to the incorrect usage of game logic RNG. This code block is required to
+						// forward the game logic RNG and keep things consistent.
+						if (sys)
+						{
+							Coord3D offs = { 0,0,0 };
+							curVictim->getGeometryInfo().makeGameLogicRandomOffsetWithinFootprint(offs);
+							static_cast<void>(GameLogicRandomValue(0, 1));
+							static_cast<void>(GameLogicRandomValue(0, 1));
+						}
+#endif
 					}
 				}
-			}
 
+			}
 		}
 	}
 

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Update/SpecialAbilityUpdate.cpp

@@ -1404,13 +1404,24 @@ void SpecialAbilityUpdate::triggerAbilityEffect()
           if (sys)
           {
             Coord3D offs = {0,0,0};
-            target->getGeometryInfo().makeRandomOffsetWithinFootprint( offs );
+            target->getGeometryInfo().makeGameClientRandomOffsetWithinFootprint( offs );
 
             sys->attachToObject(target);
             sys->setPosition( &offs );
             sys->setSystemLifetime( data->m_effectDuration * durationInterleaveFactor ); //lifetime of the system, not the particles
 
           }
+
+#if RETAIL_COMPATIBLE_CRC
+          // TheSuperHackers @fix stephanmeesters 18/05/2026 Fix issue where the creation of a certain particle system
+          // would influence game logic CRC due to the incorrect usage of game logic RNG. This code block is required to
+          // forward the game logic RNG and keep things consistent.
+          if (sys)
+          {
+            Coord3D offs = { 0,0,0 };
+            target->getGeometryInfo().makeGameLogicRandomOffsetWithinFootprint(offs);
+          }
+#endif
         }
       }
       break;