Skip to content

BlockCollisionChanges: Add 1.21.5+ support (ladders) #93

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
florianreuth merged 1 commit into from
Jul 27, 2025
Merged

BlockCollisionChanges: Add 1.21.5+ support (ladders) #93

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
59 changes: 43 additions & 16 deletions src/main/java/com/viaversion/viarewind/legacysupport/feature/BlockCollisionChanges.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -25,6 +25,7 @@
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

Expand Down Expand Up @@ -56,22 +57,48 @@ public static void fixCarpet(final Logger logger, final ProtocolVersion serverVe

public static void fixLadder(final Logger logger, final ProtocolVersion serverVersion) {
try {
final boolean pre1_12_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_12_2);
final boolean pre1_13_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_13_2);
final boolean pre1_16_4 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_16_4);
final boolean pre1_20_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_20_2);

final Class<?> blockLadderClass = getNMSBlockClass("BlockLadder");

final Field boundingBoxEastField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "b" : pre1_13_2 ? "c" : pre1_16_4 ? "c" : pre1_20_2 ? "d" : "e");
final Field boundingBoxWestField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "c" : pre1_13_2 ? "o" : pre1_16_4 ? "d" : pre1_20_2 ? "e" : "f");
final Field boundingBoxSouthField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "d" : pre1_13_2 ? "p" : pre1_16_4 ? "e" : pre1_20_2 ? "f" : "g");
final Field boundingBoxNorthField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "e" : pre1_13_2 ? "q" : pre1_16_4 ? "f" : pre1_20_2 ? "g" : "h");

setBoundingBox(boundingBoxEastField.get(null), 0.0D, 0.0D, 0.0D, 0.125D, 1.0D, 1.0D);
setBoundingBox(boundingBoxWestField.get(null), 0.875D, 0.0D, 0.0D, 1.0D, 1.0D, 1.0D);
setBoundingBox(boundingBoxSouthField.get(null), 0.0D, 0.0D, 0.0D, 1.0D, 1.0D, 0.125D);
setBoundingBox(boundingBoxNorthField.get(null), 0.0D, 0.0D, 0.875D, 1.0D, 1.0D, 1.0D);
if(serverVersion.newerThanOrEqualTo(ProtocolVersion.v1_20_5))
{
final Class<?> blockLadderClass = getNMSBlockClass("BlockLadder");
final Field shapesField = getFieldAccessible(blockLadderClass, "d"); // SHAPES field
shapesField.setAccessible(true);

Class<?> blockClass = Class.forName("net.minecraft.world.level.block.Block");
Method boxZMethod = blockClass.getDeclaredMethod("boxZ", double.class, double.class, double.class);
boxZMethod.setAccessible(true);
Object voxelShape = boxZMethod.invoke(null, 16.0, 14.0, 16.0);

Class<?> shapesClass = Class.forName("net.minecraft.world.phys.shapes.Shapes");
Class<?> voxelShapeInterface = Class.forName("net.minecraft.world.phys.shapes.VoxelShape");
Method rotateHorizontalMethod = shapesClass.getDeclaredMethod("rotateHorizontal", voxelShapeInterface);
rotateHorizontalMethod.setAccessible(true);
@SuppressWarnings("unchecked")
Map<Object, Object> rotatedMap = (Map<Object, Object>) rotateHorizontalMethod.invoke(null, voxelShape);

@SuppressWarnings("unchecked")
Map<Object, Object> shapes = (Map<Object, Object>) shapesField.get(null);
shapes.clear();
shapes.putAll(rotatedMap);
}
else
{
final boolean pre1_12_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_12_2);
final boolean pre1_13_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_13_2);
final boolean pre1_16_4 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_16_4);
final boolean pre1_20_2 = serverVersion.olderThanOrEqualTo(ProtocolVersion.v1_20_2);

final Class<?> blockLadderClass = getNMSBlockClass("BlockLadder");

final Field boundingBoxEastField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "b" : pre1_13_2 ? "c" : pre1_16_4 ? "c" : pre1_20_2 ? "d" : "e");
final Field boundingBoxWestField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "c" : pre1_13_2 ? "o" : pre1_16_4 ? "d" : pre1_20_2 ? "e" : "f");
final Field boundingBoxSouthField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "d" : pre1_13_2 ? "p" : pre1_16_4 ? "e" : pre1_20_2 ? "f" : "g");
final Field boundingBoxNorthField = getFieldAccessible(blockLadderClass, pre1_12_2 ? "e" : pre1_13_2 ? "q" : pre1_16_4 ? "f" : pre1_20_2 ? "g" : "h");

setBoundingBox(boundingBoxEastField.get(null), 0.0D, 0.0D, 0.0D, 0.125D, 1.0D, 1.0D);
setBoundingBox(boundingBoxWestField.get(null), 0.875D, 0.0D, 0.0D, 1.0D, 1.0D, 1.0D);
setBoundingBox(boundingBoxSouthField.get(null), 0.0D, 0.0D, 0.0D, 1.0D, 1.0D, 0.125D);
setBoundingBox(boundingBoxNorthField.get(null), 0.0D, 0.0D, 0.875D, 1.0D, 1.0D, 1.0D);
}
} catch (Exception ex) {
logger.log(Level.SEVERE, "Could not fix ladder bounding box.", ex);
}
Expand Down