[needs testing] Fix linear actuator offset logic and fix clamps to be of more logical value

src/main/java/com/simibubi/create/content/contraptions/ContraptionCollider.java

@@ -14,7 +14,6 @@
 import org.apache.commons.lang3.mutable.MutableObject;
 import org.apache.commons.lang3.tuple.MutablePair;
 
-import com.simibubi.create.AllBlocks;
 import com.simibubi.create.AllPackets;
 import com.simibubi.create.api.behaviour.interaction.MovingInteractionBehaviour;
 import com.simibubi.create.api.behaviour.movement.MovementBehaviour;
@@ -701,7 +700,6 @@ public static boolean collideBlocks(AbstractContraptionEntity contraptionEntity)
 		TranslatingContraption contraption = (TranslatingContraption) contraptionEntity.getContraption();
 		AABB bounds = contraptionEntity.getBoundingBox();
 		Vec3 position = contraptionEntity.position();
-		BlockPos gridPos = BlockPos.containing(position);
 
 		if (contraption == null)
 			return false;
@@ -713,8 +711,13 @@ public static boolean collideBlocks(AbstractContraptionEntity contraptionEntity)
 		Direction movementDirection = Direction.getNearest(motion.x, motion.y, motion.z);
 
 		// Blocks in the world
-		if (movementDirection.getAxisDirection() == AxisDirection.POSITIVE)
-			gridPos = gridPos.relative(movementDirection);
+		if (movementDirection.getAxisDirection() == AxisDirection.POSITIVE) {
+			Axis ax = movementDirection.getAxis();
+			position = position.with(ax, Math.ceil(position.get(ax)));
+		}
+
+		BlockPos gridPos = BlockPos.containing(position);
+
 		if (isCollidingWithWorld(world, contraption, gridPos, movementDirection))
 			return true;
 
@@ -766,29 +769,32 @@ public static boolean isCollidingWithWorld(Level world, TranslatingContraption c
 			boolean emptyCollider = collidedState.getCollisionShape(world, pos)
 				.isEmpty();
 
+			if (emptyCollider) continue;
+
 			if (collidedState.getBlock() instanceof CocoaBlock)
 				continue;
 
 			MovementBehaviour movementBehaviour = MovementBehaviour.REGISTRY.get(blockInfo.state());
 			if (movementBehaviour != null) {
 				if (movementBehaviour instanceof BlockBreakingMovementBehaviour behaviour) {
-					if (!behaviour.canBreak(world, colliderPos, collidedState) && !emptyCollider)
+					if (!behaviour.canBreak(world, colliderPos, collidedState))
 						return true;
 					continue;
 				}
 				if (movementBehaviour instanceof HarvesterMovementBehaviour harvesterMovementBehaviour) {
 					if (!harvesterMovementBehaviour.isValidCrop(world, colliderPos, collidedState)
-						&& !harvesterMovementBehaviour.isValidOther(world, colliderPos, collidedState)
-						&& !emptyCollider)
+						&& !harvesterMovementBehaviour.isValidOther(world, colliderPos, collidedState))
 						return true;
 					continue;
 				}
 			}
 
-			if (AllBlocks.PULLEY_MAGNET.has(collidedState) && pos.equals(BlockPos.ZERO)
-				&& movementDirection == Direction.UP)
-				continue;
-			if (!collidedState.canBeReplaced() && !emptyCollider) {
+			// This case exists for the mechanical piston, because it intersects with its own contraption
+			if (contraption.entity instanceof ControlledContraptionEntity cce) {
+				if (cce.controllerPos.equals(colliderPos)) continue;
+			}
+
+			if (!collidedState.canBeReplaced()) {
 				return true;
 			}
 

src/main/java/com/simibubi/create/content/contraptions/gantry/GantryContraptionEntity.java

@@ -69,16 +69,19 @@ protected void tickContraption() {
 		tickActors();
 		Vec3 movementVec = getDeltaMovement();
 
-		if (ContraptionCollider.collideBlocks(this)) {
-			if (!level().isClientSide)
-				disassemble();
-			return;
-		}
-
 		if (!isStalled() && tickCount > 2) {
 			if (sequencedOffsetLimit >= 0)
 				movementVec = VecHelper.clampComponentWise(movementVec, (float) sequencedOffsetLimit);
+
 			move(movementVec.x, movementVec.y, movementVec.z);
+			if (ContraptionCollider.collideBlocks(this)) {
+				move(-movementVec.x, -movementVec.y, -movementVec.z);
+
+				if (!level().isClientSide)
+					disassemble();
+				return;
+			}
+
 			if (sequencedOffsetLimit > 0)
 				sequencedOffsetLimit = Math.max(0, sequencedOffsetLimit - movementVec.length());
 		}

src/main/java/com/simibubi/create/content/contraptions/piston/LinearActuatorBlockEntity.java

@@ -289,7 +289,7 @@ protected void tryDisassemble() {
 			return;
 		}
 		int initial = getInitialOffset();
-		if ((int) (offset + .5f) != initial && getMovementMode() == MovementMode.MOVE_PLACE_RETURNED) {
+		if (getMovementMode() == MovementMode.MOVE_PLACE_RETURNED && getGridOffset(offset) != initial) {
 			waitingForSpeedChange = true;
 			return;
 		}
@@ -319,7 +319,7 @@ protected void collided() {
 			waitingForSpeedChange = true;
 			return;
 		}
-		offset = getGridOffset(offset - getMovementSpeed());
+
 		resetContraptionToOffset();
 		tryDisassemble();
 	}
@@ -336,7 +336,7 @@ protected void resetContraptionToOffset() {
 	}
 
 	public float getMovementSpeed() {
-		float movementSpeed = Mth.clamp(convertToLinear(getSpeed()), -.49f, .49f) + clientOffsetDiff / 2f;
+		float movementSpeed = Mth.clamp(convertToLinear(getSpeed()), -1, 1) + clientOffsetDiff / 2f;
 		if (level.isClientSide)
 			movementSpeed *= ServerSpeedProvider.get();
 		if (sequencedOffsetLimit >= 0)

src/main/java/com/simibubi/create/content/contraptions/piston/MechanicalPistonBlockEntity.java

@@ -15,6 +15,7 @@
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.Direction.Axis;
+import net.minecraft.core.HolderLookup;
 import net.minecraft.core.Direction.AxisDirection;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.util.Mth;
@@ -25,7 +26,6 @@
 
 public class MechanicalPistonBlockEntity extends LinearActuatorBlockEntity {
 
-	protected boolean hadCollisionWithOtherPiston;
 	protected int extensionLength;
 
 	public MechanicalPistonBlockEntity(BlockEntityType<?> type, BlockPos pos, BlockState state) {
@@ -52,26 +52,15 @@ public void assemble() throws AssemblyException {
 
 		Direction direction = getBlockState().getValue(BlockStateProperties.FACING);
 
-		// Collect Construct
+		// Assemble contraption first (getMovementSpeed may already exist)
 		PistonContraption contraption = new PistonContraption(direction, getMovementSpeed() < 0);
 		if (!contraption.assemble(level, worldPosition))
 			return;
 
-		Direction positive = Direction.get(AxisDirection.POSITIVE, direction.getAxis());
-		Direction movementDirection =
-			getSpeed() > 0 ^ direction.getAxis() != Axis.Z ? positive : positive.getOpposite();
-
-		BlockPos anchor = contraption.anchor.relative(direction, contraption.initialExtensionProgress);
-		if (ContraptionCollider.isCollidingWithWorld(level, contraption, anchor.relative(movementDirection),
-			movementDirection))
-			return;
-
-		// Check if not at limit already
 		extensionLength = contraption.extensionLength;
-		float resultingOffset = contraption.initialExtensionProgress + Math.signum(getMovementSpeed()) * .5f;
-		if (resultingOffset <= 0 || resultingOffset >= extensionLength) {
-			return;
-		}
+
+		// If piston cannot move, do not assemble
+		if (getMovementSpeed() == 0) return;
 
 		// Run
 		running = true;
@@ -87,7 +76,7 @@ public void assemble() throws AssemblyException {
 		level.addFreshEntity(movedContraption);
 
 		AllSoundEvents.CONTRAPTION_ASSEMBLE.playOnServer(level, worldPosition);
-		
+
 		if (contraption.containsBlockBreakers())
 			award(AllAdvancements.CONTRAPTION_ACTORS);
 	}
@@ -122,7 +111,7 @@ protected void collided() {
 
 	@Override
 	public float getMovementSpeed() {
-		float movementSpeed = Mth.clamp(convertToLinear(getSpeed()), -.49f, .49f);
+		float movementSpeed = Mth.clamp(convertToLinear(getSpeed()), -1, 1);
 		if (level.isClientSide)
 			movementSpeed *= ServerSpeedProvider.get();
 		Direction pistonDirection = getBlockState().getValue(BlockStateProperties.FACING);

src/main/java/com/simibubi/create/content/kinetics/gantry/GantryShaftBlockEntity.java

@@ -104,7 +104,7 @@ public float getPinionMovementSpeed() {
 		BlockState blockState = getBlockState();
 		if (!AllBlocks.GANTRY_SHAFT.has(blockState))
 			return 0;
-		return Mth.clamp(convertToLinear(-getSpeed()), -.49f, .49f);
+		return Mth.clamp(convertToLinear(-getSpeed()), -1, 1);
 	}
 
 	@Override