javadocs + default cause lazy + fix yo stuff

src/main/java/gregtech/api/metatileentity/multiblock/IMultiblockPart.java

@@ -13,6 +13,7 @@ public interface IMultiblockPart {
     /**
      * Gets how many multiblocks are currently using the part.
      */
+    // todo do a concrete impl
     default int getWallsharedCount() { return 1;}
 
     default boolean canPartShare(MultiblockControllerBase target, String substructureName) {

src/main/java/gregtech/api/metatileentity/multiblock/MultiblockControllerBase.java

@@ -11,7 +11,6 @@
 import gregtech.api.pattern.BlockWorldState;
 import gregtech.api.pattern.MultiblockShapeInfo;
 import gregtech.api.pattern.PatternMatchContext;
-import gregtech.api.pattern.StructureInfo;
 import gregtech.api.pattern.TraceabilityPredicate;
 import gregtech.api.pattern.pattern.IBlockPattern;
 import gregtech.api.pattern.pattern.PatternInfo;
@@ -147,6 +146,8 @@ private void validateStructurePatterns() {
         List<String> failures = new ArrayList<>();
 
         for (Object2ObjectMap.Entry<String, PatternInfo> pattern : structures.object2ObjectEntrySet()) {
+            if ("MAIN".equals(pattern.getKey())) continue;
+
             if (pattern.getValue().getPattern().legacyBuilderError()) {
                 failures.add(pattern.getKey());
             }
@@ -183,7 +184,6 @@ public void setUpwardsFacing(EnumFacing upwardsFacing) {
     }
 
     public boolean isFlipped() {
-        if (getSubstructure("MAIN") == null) return false;
         return getSubstructure("MAIN").isFlipped();
     }
 
@@ -368,19 +368,19 @@ protected Function<BlockPos, Integer> multiblockPartSorter() {
         return BlockPos::hashCode;
     }
 
-    public void checkStructurePattern() {
-        checkStructurePattern("MAIN");
-    }
-
     public void checkStructurePatterns() {
         for (String name : structures.keySet()) {
             checkStructurePattern(name);
         }
     }
 
+    public void checkStructurePattern() {
+        checkStructurePattern("MAIN");
+    }
+
     public void checkStructurePattern(String name) {
         PatternInfo pattern = getSubstructure(name);
-        if (pattern == null || !pattern.shouldUpdate) return;
+        if (!pattern.shouldUpdate) return;
 
         long time = System.nanoTime();
         PatternMatchContext context = pattern.getPattern().checkPatternFastAt(getWorld(), getPos(),
@@ -433,7 +433,7 @@ protected void formStructure(PatternMatchContext context, String name) {
         // form the main structure
         if ("MAIN".equals(name)) formStructure(context);
 
-        if (getSubstructure(name) != null) getSubstructure(name).setFormed(true);
+        getSubstructure(name).setFormed(true);
     }
 
     public void invalidateStructure() {
@@ -529,7 +529,7 @@ public void receiveCustomData(int dataId, PacketBuffer buf) {
                     pattern.setFormed(false);
                 }
             } else {
-                getSubstructure(name).setFormed(false);
+                getSubstructure(name).setFormed(buf.readBoolean());
             }
 
             if (!isStructureFormed()) {
@@ -554,6 +554,8 @@ public boolean isStructureFormed() {
     }
 
     public boolean isStructureFormed(String name) {
+        if (getWorld() == null) return false;
+
         return getSubstructure(name).isFormed();
     }
 
@@ -659,6 +661,8 @@ public List<PreviewBlockPattern> getBuildableShapes(@Nullable Object2IntMap<Stri
 
                 // only generate for the first pattern, if you have more than 1 pattern you better override this
                 defaultPattern = getSubstructure("MAIN").getPattern().getDefaultShape();
+
+                if (defaultPattern == null) return Collections.emptyList();
             }
 
             return Collections.singletonList(defaultPattern);

src/main/java/gregtech/api/pattern/pattern/BlockPattern.java

@@ -101,15 +101,11 @@ private void legacyStartOffset(char center) {
         for (int aisleI = 0; aisleI < dimensions[0]; aisleI++) {
             int[] result = aisles[aisleI].firstInstanceOf(center);
             if (result != null) {
-                // the ordinal() / 2 is so that each relative offset gets put into the correct startOffset
-
-                // when legacyStartOffset() is called, aisles have been reversed, so don't reverse it manually here
-                // the scuffed ternary is so that if the structure dir is the second thing, then don't reverse it
-                startOffset[structureDir[0].ordinal() / 2] = aisleI * (structureDir[0].ordinal() % 2 == 0 ? -1 : 1);
-                startOffset[structureDir[1].ordinal() / 2] = (dimensions[1] - 1 - result[0]) *
-                        (structureDir[1].ordinal() % 2 == 0 ? -1 : 1);
-                startOffset[structureDir[2].ordinal() / 2] = (dimensions[2] - 1 - result[1]) *
-                        (structureDir[2].ordinal() % 2 == 0 ? -1 : 1);
+                // structure starts at aisle 0, string 0, char 0, think about it
+                // so relative to the controller we need to offset by this to get to the start
+                moveStartOffset(structureDir[0], -aisleI);
+                moveStartOffset(structureDir[1], -result[0]);
+                moveStartOffset(structureDir[2], -result[1]);
                 return;
             }
         }
@@ -256,7 +252,7 @@ public boolean checkAisle(GreggyBlockPos controllerPos, EnumFacing frontFacing,
                             !(te instanceof IGregTechTileEntity gtTe) || gtTe.isValid() ? te : null, predicate));
                 }
 
-                GTLog.logger.info("Checked pos at " + charPos + " with flip " + flip);
+//                GTLog.logger.info("Checked pos at " + charPos + " with flip " + flip);
 
                 boolean result = predicate.test(worldState, info, globalCount, layerCount);
                 if (!result) return false;

src/main/java/gregtech/api/pattern/pattern/ExpandablePattern.java

@@ -39,6 +39,12 @@ public class ExpandablePattern implements IBlockPattern {
     protected final Long2ObjectMap<BlockInfo> cache = new Long2ObjectOpenHashMap<>();
     protected final Object2IntMap<TraceabilityPredicate.SimplePredicate> globalCount = new Object2IntOpenHashMap<>();
 
+    /**
+     * New expandable pattern normally you would use {@link FactoryExpandablePattern} instead.
+     * @param boundsFunction A function to supply bounds, order in the way .values() are ordered in RelativeDirection.
+     * @param predicateFunction Given a pos and bounds(the one you just passed in, not mutated), return a predicate. The pos is offset as explained in the builder method.
+     * @param directions The structure directions, explained in the builder method.
+     */
     public ExpandablePattern(@NotNull QuadFunction<World, GreggyBlockPos, EnumFacing, EnumFacing, int[]> boundsFunction,
                              @NotNull BiFunction<GreggyBlockPos, int[], TraceabilityPredicate> predicateFunction,
                              @NotNull RelativeDirection[] directions) {
@@ -157,6 +163,7 @@ public boolean checkPatternAt(World world, BlockPos centerPos, EnumFacing frontF
 
     @Override
     public PreviewBlockPattern getDefaultShape() {
+        // todo undo
         return null;
     }
 

src/main/java/gregtech/api/pattern/pattern/FactoryExpandablePattern.java

@@ -41,20 +41,38 @@ private FactoryExpandablePattern(RelativeDirection aisleDir, RelativeDirection s
         if (flags != 0x7) throw new IllegalArgumentException("Must have 3 different axes!");
     }
 
+    /**
+     * Starts a new builder using the provided directions.
+     */
     public static FactoryExpandablePattern start(RelativeDirection aisleDir, RelativeDirection stringDir,
                                                  RelativeDirection charDir) {
         return new FactoryExpandablePattern(aisleDir, stringDir, charDir);
     }
 
+    /**
+     * Same as calling {@link FactoryExpandablePattern#start(RelativeDirection, RelativeDirection, RelativeDirection)} with BACK, UP, RIGHT
+     */
     public static FactoryExpandablePattern start() {
         return new FactoryExpandablePattern(RelativeDirection.BACK, RelativeDirection.UP, RelativeDirection.RIGHT);
     }
 
+    /**
+     * This supplies the bounds function. The inputs are: World, controller pos, front facing, up facing. The returned array
+     * is an int array of length 6, with how much to extend the multiblock in each direction. The order of the directions is the same
+     * as the ordinal of the enum.
+     */
     public FactoryExpandablePattern boundsFunction(QuadFunction<World, GreggyBlockPos, EnumFacing, EnumFacing, int[]> function) {
         this.boundsFunction = function;
         return this;
     }
 
+    /**
+     * This supplies the predicate from offset pos and the bounds, which is not mutated. The pos is offset so that the controller
+     * is at the origin(0, 0, 0). The 3 axes are positive towards the way structure direction is handled. The pos starts as usual,
+     * which means it will always be in octant 7. It then ends in octant 1, in the opposite corner to the start corner in the cube specified by the bounding box.
+     * The pos travels as expected from the structure direction, traveling first in charDir, then upon going out of bounds once in stringDir and resetting
+     * its charDir pos. Same happens when stringDir goes out of bounds and reset, then aisleDir is incremented.
+     */
     public FactoryExpandablePattern predicateFunction(BiFunction<GreggyBlockPos, int[], TraceabilityPredicate> function) {
         this.predicateFunction = function;
         return this;