cool vine and ladder descending, fixes #159

src/main/java/baritone/pathing/calc/AStarPathFinder.java

@@ -121,7 +121,7 @@ public final class AStarPathFinder extends AbstractNodeCostSearch implements Hel
                 if (actionCost >= ActionCosts.COST_INF) {
                     continue;
                 }
-                if (actionCost <= 0) {
+                if (actionCost <= 0 || Double.isNaN(actionCost)) {
                     throw new IllegalStateException(moves + " calculated implausible cost " + actionCost);
                 }
                 if (moves.dynamicXZ && !worldBorder.entirelyContains(res.x, res.z)) { // see issue #218

src/main/java/baritone/pathing/calc/PathNode.java

@@ -73,6 +73,9 @@ public final class PathNode {
         this.previous = null;
         this.cost = ActionCosts.COST_INF;
         this.estimatedCostToGoal = goal.heuristic(x, y, z);
+        if (Double.isNaN(estimatedCostToGoal)) {
+            throw new IllegalStateException(goal + " calculated implausible heuristic");
+        }
         this.isOpen = false;
         this.x = x;
         this.y = y;

src/main/java/baritone/pathing/movement/movements/MovementDescend.java

@@ -115,66 +115,84 @@ public class MovementDescend extends Movement {
         res.cost = totalCost;
     }
 
-    public static void dynamicFallCost(CalculationContext context, int x, int y, int z, int destX, int destZ, double frontBreak, IBlockState below, MutableMoveResult res) {
+    public static boolean dynamicFallCost(CalculationContext context, int x, int y, int z, int destX, int destZ, double frontBreak, IBlockState below, MutableMoveResult res) {
         if (frontBreak != 0 && context.get(destX, y + 2, destZ).getBlock() instanceof BlockFalling) {
             // if frontBreak is 0 we can actually get through this without updating the falling block and making it actually fall
             // but if frontBreak is nonzero, we're breaking blocks in front, so don't let anything fall through this column,
             // and potentially replace the water we're going to fall into
-            return;
+            return false;
         }
         if (!MovementHelper.canWalkThrough(context.bsi(), destX, y - 2, destZ, below) && below.getBlock() != Blocks.WATER) {
-            return;
+            return false;
         }
+        double costSoFar = 0;
+        int effectiveStartHeight = y;
         for (int fallHeight = 3; true; fallHeight++) {
             int newY = y - fallHeight;
             if (newY < 0) {
                 // when pathing in the end, where you could plausibly fall into the void
                 // this check prevents it from getting the block at y=-1 and crashing
-                return;
+                return false;
             }
             IBlockState ontoBlock = context.get(destX, newY, destZ);
-            double tentativeCost = WALK_OFF_BLOCK_COST + FALL_N_BLOCKS_COST[fallHeight] + frontBreak;
+            int unprotectedFallHeight = fallHeight - (y - effectiveStartHeight); // equal to fallHeight - y + effectiveFallHeight, which is equal to -newY + effectiveFallHeight, which is equal to effectiveFallHeight - newY
-            if (ontoBlock.getBlock() == Blocks.WATER && !MovementHelper.isFlowing(ontoBlock) && context.getBlock(destX, newY + 1, destZ) != Blocks.WATERLILY) { // TODO flowing check required here?
+            double tentativeCost = WALK_OFF_BLOCK_COST + FALL_N_BLOCKS_COST[unprotectedFallHeight] + frontBreak + costSoFar;
+            if (ontoBlock.getBlock() == Blocks.WATER && context.getBlock(destX, newY + 1, destZ) != Blocks.WATERLILY) {
                 // lilypads are canWalkThrough, but we can't end a fall that should be broken by water if it's covered by a lilypad
                 // however, don't return impossible in the lilypad scenario, because we could still jump right on it (water that's below a lilypad is canWalkOn so it works)
                 if (context.assumeWalkOnWater()) {
-                    return; // TODO fix
+                    return false; // TODO fix
+                }
+                if (MovementHelper.isFlowing(ontoBlock)) {
+                    return false; // TODO flowing check required here?
+                }
+                if (!MovementHelper.canWalkOn(context.bsi(), destX, newY - 1, destZ)) {
+                    // we could punch right through the water into something else
+                    return false;
                 }
                 // found a fall into water
                 res.x = destX;
                 res.y = newY;
                 res.z = destZ;
                 res.cost = tentativeCost;// TODO incorporate water swim up cost?
-                return;
+                return false;
             }
             if (ontoBlock.getBlock() == Blocks.FLOWING_WATER) {
-                return;
+                return false;
+            }
+            if (unprotectedFallHeight <= 11 && (ontoBlock.getBlock() == Blocks.VINE || ontoBlock.getBlock() == Blocks.LADDER)) {
+                // if fall height is greater than or equal to 11, we don't actually grab on to vines or ladders. the more you know
+                // this effectively "resets" our falling speed
+                costSoFar += FALL_N_BLOCKS_COST[unprotectedFallHeight - 1];// we fall until the top of this block (not including this block)
+                costSoFar += LADDER_DOWN_ONE_COST;
+                effectiveStartHeight = newY;
+                continue;
             }
             if (MovementHelper.canWalkThrough(context.bsi(), destX, newY, destZ, ontoBlock)) {
                 continue;
             }
             if (!MovementHelper.canWalkOn(context.bsi(), destX, newY, destZ, ontoBlock)) {
-                return;
+                return false;
             }
             if (MovementHelper.isBottomSlab(ontoBlock)) {
-                return; // falling onto a half slab is really glitchy, and can cause more fall damage than we'd expect
+                return false; // falling onto a half slab is really glitchy, and can cause more fall damage than we'd expect
             }
-            if (context.hasWaterBucket() && fallHeight <= context.maxFallHeightBucket() + 1) {
+            if (context.hasWaterBucket() && unprotectedFallHeight <= context.maxFallHeightBucket() + 1) {
                 res.x = destX;
                 res.y = newY + 1;// this is the block we're falling onto, so dest is +1
                 res.z = destZ;
                 res.cost = tentativeCost + context.placeBlockCost();
-                return;
+                return true;
             }
-            if (fallHeight <= context.maxFallHeightNoWater() + 1) {
+            if (unprotectedFallHeight <= context.maxFallHeightNoWater() + 1) {
                 // fallHeight = 4 means onto.up() is 3 blocks down, which is the max
                 res.x = destX;
                 res.y = newY + 1;
                 res.z = destZ;
                 res.cost = tentativeCost;
-                return;
+                return false;
             } else {
-                return;
+                return false;
             }
         }
     }

src/main/java/baritone/pathing/movement/movements/MovementFall.java

@@ -17,7 +17,6 @@
 
 package baritone.pathing.movement.movements;
 
-import baritone.Baritone;
 import baritone.api.IBaritone;
 import baritone.api.pathing.movement.MovementStatus;
 import baritone.api.utils.BetterBlockPos;
@@ -31,12 +30,19 @@ import baritone.pathing.movement.MovementHelper;
 import baritone.pathing.movement.MovementState;
 import baritone.pathing.movement.MovementState.MovementTarget;
 import baritone.utils.pathing.MutableMoveResult;
+import net.minecraft.block.BlockLadder;
+import net.minecraft.block.state.IBlockState;
 import net.minecraft.entity.player.InventoryPlayer;
+import net.minecraft.init.Blocks;
 import net.minecraft.init.Items;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.RayTraceResult;
 import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.Vec3i;
+
+import java.util.Optional;
 
 public class MovementFall extends Movement {
 
@@ -57,6 +63,12 @@ public class MovementFall extends Movement {
         return result.cost;
     }
 
+    private boolean willPlaceBucket() {
+        CalculationContext context = new CalculationContext(baritone);
+        MutableMoveResult result = new MutableMoveResult();
+        return MovementDescend.dynamicFallCost(context, src.x, src.y, src.z, dest.x, dest.z, 0, context.get(dest.x, src.y - 2, dest.z), result);
+    }
+
     @Override
     public MovementState updateState(MovementState state) {
         super.updateState(state);
@@ -67,7 +79,7 @@ public class MovementFall extends Movement {
         BlockPos playerFeet = ctx.playerFeet();
         Rotation toDest = RotationUtils.calcRotationFromVec3d(ctx.playerHead(), VecUtils.getBlockPosCenter(dest));
         Rotation targetRotation = null;
-        if (!MovementHelper.isWater(ctx, dest) && src.getY() - dest.getY() > Baritone.settings().maxFallHeightNoWater.get() && !playerFeet.equals(dest)) {
+        if (!MovementHelper.isWater(ctx, dest) && willPlaceBucket() && !playerFeet.equals(dest)) {
             if (!InventoryPlayer.isHotbar(ctx.player().inventory.getSlotFor(STACK_BUCKET_WATER)) || ctx.world().provider.isNether()) {
                 return state.setStatus(MovementStatus.UNREACHABLE);
             }
@@ -78,7 +90,7 @@ public class MovementFall extends Movement {
                 targetRotation = new Rotation(toDest.getYaw(), 90.0F);
 
                 RayTraceResult trace = ctx.objectMouseOver();
-                if (trace != null && trace.typeOfHit == RayTraceResult.Type.BLOCK && ctx.player().rotationPitch > 89.0F) {
+                if (trace != null && trace.typeOfHit == RayTraceResult.Type.BLOCK && (trace.getBlockPos().equals(dest) || trace.getBlockPos().equals(dest.down()))) {
                     state.setInput(Input.CLICK_RIGHT, true);
                 }
             }
@@ -107,12 +119,40 @@ public class MovementFall extends Movement {
             }
         }
         Vec3d destCenter = VecUtils.getBlockPosCenter(dest); // we are moving to the 0.5 center not the edge (like if we were falling on a ladder)
-        if (Math.abs(ctx.player().posX - destCenter.x) > 0.15 || Math.abs(ctx.player().posZ - destCenter.z) > 0.15) {
+        if (Math.abs(ctx.player().posX + ctx.player().motionX - destCenter.x) > 0.1 || Math.abs(ctx.player().posZ + ctx.player().motionZ - destCenter.z) > 0.1) {
+            if (!ctx.player().onGround && Math.abs(ctx.player().motionY) > 0.4) {
+                state.setInput(Input.SNEAK, true);
+            }
             state.setInput(Input.MOVE_FORWARD, true);
         }
+        Vec3i avoid = Optional.ofNullable(avoid()).map(EnumFacing::getDirectionVec).orElse(null);
+        if (avoid == null) {
+            avoid = src.subtract(dest);
+        } else {
+            double dist = Math.abs(avoid.getX() * (destCenter.x - avoid.getX() / 2.0 - ctx.player().posX)) + Math.abs(avoid.getZ() * (destCenter.z - avoid.getZ() / 2.0 - ctx.player().posZ));
+            if (dist < 0.6) {
+                state.setInput(Input.MOVE_FORWARD, true);
+            } else {
+                state.setInput(Input.SNEAK, false);
+            }
+        }
+        if (targetRotation == null) {
+            Vec3d destCenterOffset = new Vec3d(destCenter.x + 0.125 * avoid.getX(), destCenter.y, destCenter.z + 0.125 * avoid.getZ());
+            state.setTarget(new MovementTarget(RotationUtils.calcRotationFromVec3d(ctx.playerHead(), destCenterOffset), false));
+        }
         return state;
     }
 
+    private EnumFacing avoid() {
+        for (int i = 0; i < 15; i++) {
+            IBlockState state = ctx.world().getBlockState(ctx.playerFeet().down(i));
+            if (state.getBlock() == Blocks.LADDER) {
+                return state.getValue(BlockLadder.FACING);
+            }
+        }
+        return null;
+    }
+
     @Override
     public boolean safeToCancel(MovementState state) {
         // if we haven't started walking off the edge yet, or if we're in the process of breaking blocks before doing the fall