Minestom/src/main/java/net/minestom/server/collision/BoundingBox.java

279 lines
9.9 KiB
Java

package net.minestom.server.collision;
import net.minestom.server.coordinate.Point;
import net.minestom.server.coordinate.Pos;
import net.minestom.server.coordinate.Vec;
import net.minestom.server.entity.Entity;
import org.jetbrains.annotations.ApiStatus;
import org.jetbrains.annotations.NotNull;
import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.stream.Stream;
/**
* See https://wiki.vg/Entity_metadata#Mobs_2
*/
public final class BoundingBox implements Shape {
private final double width, height, depth;
private final Point offset;
private Map<Vec, Vec[]> faces;
BoundingBox(double width, double height, double depth, Point offset) {
this.width = width;
this.height = height;
this.depth = depth;
this.offset = offset;
}
public BoundingBox(double width, double height, double depth) {
this(width, height, depth, new Vec(-width / 2, 0, -depth / 2));
}
@Override
@ApiStatus.Experimental
public boolean intersectBox(@NotNull Point positionRelative, @NotNull BoundingBox boundingBox) {
return (minX() + positionRelative.x() <= boundingBox.maxX() && maxX() + positionRelative.x() >= boundingBox.minX()) &&
(minY() + positionRelative.y() <= boundingBox.maxY() && maxY() + positionRelative.y() >= boundingBox.minY()) &&
(minZ() + positionRelative.z() <= boundingBox.maxZ() && maxZ() + positionRelative.z() >= boundingBox.minZ());
}
@Override
@ApiStatus.Experimental
public boolean intersectBoxSwept(@NotNull Point rayStart, @NotNull Point rayDirection, @NotNull Point shapePos, @NotNull BoundingBox moving, @NotNull SweepResult finalResult) {
final boolean isHit = RayUtils.BoundingBoxIntersectionCheck(
moving, rayStart, rayDirection,
this,
shapePos
);
if (!isHit) return false;
SweepResult tempResult = new SweepResult(1, 0, 0, 0, null);
// Longer check to get result of collision
RayUtils.SweptAABB(moving, rayStart, rayDirection, this, shapePos, tempResult);
// Update final result if the temp result collision is sooner than the current final result
if (tempResult.res < finalResult.res) {
finalResult.res = tempResult.res;
finalResult.normalX = tempResult.normalX;
finalResult.normalY = tempResult.normalY;
finalResult.normalZ = tempResult.normalZ;
finalResult.collidedShapePosition = shapePos;
finalResult.collidedShape = this;
finalResult.blockType = null;
}
return true;
}
/**
* Used to know if this {@link BoundingBox} intersects with the bounding box of an entity.
*
* @param entity the entity to check the bounding box
* @return true if this bounding box intersects with the entity, false otherwise
*/
@ApiStatus.Experimental
public boolean intersectEntity(@NotNull Point src, @NotNull Entity entity) {
return intersectBox(src.sub(entity.getPosition()), entity.getBoundingBox());
}
@ApiStatus.Experimental
public boolean boundingBoxRayIntersectionCheck(Vec start, Vec direction, Pos position) {
return RayUtils.BoundingBoxRayIntersectionCheck(start, direction, this, position);
}
@Override
public @NotNull Point relativeStart() {
return offset;
}
@Override
public @NotNull Point relativeEnd() {
return offset.add(width, height, depth);
}
@Override
public String toString() {
String result = "BoundingBox";
result += "\n";
result += "[" + minX() + " : " + maxX() + "]";
result += "\n";
result += "[" + minY() + " : " + maxY() + "]";
result += "\n";
result += "[" + minZ() + " : " + maxZ() + "]";
return result;
}
/**
* Creates a new {@link BoundingBox} linked to the same {@link Entity} with expanded size.
*
* @param x the X offset
* @param y the Y offset
* @param z the Z offset
* @return a new {@link BoundingBox} expanded
*/
public @NotNull BoundingBox expand(double x, double y, double z) {
return new BoundingBox(this.width + x, this.height + y, this.depth + z);
}
/**
* Creates a new {@link BoundingBox} linked to the same {@link Entity} with contracted size.
*
* @param x the X offset
* @param y the Y offset
* @param z the Z offset
* @return a new bounding box contracted
*/
public @NotNull BoundingBox contract(double x, double y, double z) {
return new BoundingBox(this.width - x, this.height - y, this.depth - z);
}
public double width() {
return width;
}
public double height() {
return height;
}
public double depth() {
return depth;
}
@NotNull Map<Vec, Vec[]> faces() {
Map<Vec, Vec[]> faces = this.faces;
if (faces == null) {
this.faces = faces = retrieveFaces();
}
return faces;
}
public double minX() {
return relativeStart().x();
}
public double maxX() {
return relativeEnd().x();
}
public double minY() {
return relativeStart().y();
}
public double maxY() {
return relativeEnd().y();
}
public double minZ() {
return relativeStart().z();
}
public double maxZ() {
return relativeEnd().z();
}
private Vec[] buildSet(Collection<Vec> a) {
return a.toArray(Vec[]::new);
}
private Vec[] buildSet(Collection<Vec> a, Collection<Vec> b) {
Set<Vec> allFaces = new HashSet<>();
Stream.of(a, b).forEach(allFaces::addAll);
return allFaces.toArray(Vec[]::new);
}
private Vec[] buildSet(Collection<Vec> a, Collection<Vec> b, Collection<Vec> c) {
Set<Vec> allFaces = new HashSet<>();
Stream.of(a, b, c).forEach(allFaces::addAll);
return allFaces.toArray(Vec[]::new);
}
private Map<Vec, Vec[]> retrieveFaces() {
double minX = minX();
double maxX = maxX();
double minY = minY();
double maxY = maxY();
double minZ = minZ();
double maxZ = maxZ();
// Calculate steppings for each axis
// Start at minimum, increase by step size until we reach maximum
// This is done to catch all blocks that are part of that axis
// Since this stops before max point is reached, we add the max point after
final List<Double> stepsX = IntStream.rangeClosed(0, (int) ((maxX - minX))).mapToDouble(x -> x + minX).boxed().collect(Collectors.toCollection(ArrayList<Double>::new));
final List<Double> stepsY = IntStream.rangeClosed(0, (int) ((maxY - minY))).mapToDouble(x -> x + minY).boxed().collect(Collectors.toCollection(ArrayList<Double>::new));
final List<Double> stepsZ = IntStream.rangeClosed(0, (int) ((maxZ - minZ))).mapToDouble(x -> x + minZ).boxed().collect(Collectors.toCollection(ArrayList<Double>::new));
stepsX.add(maxX);
stepsY.add(maxY);
stepsZ.add(maxZ);
final Set<Vec> bottom = new HashSet<>();
final Set<Vec> top = new HashSet<>();
final Set<Vec> left = new HashSet<>();
final Set<Vec> right = new HashSet<>();
final Set<Vec> front = new HashSet<>();
final Set<Vec> back = new HashSet<>();
CartesianProduct.product(stepsX, stepsY).forEach(cross -> {
double i = (double) ((List<?>) cross).get(0);
double j = (double) ((List<?>) cross).get(1);
front.add(new Vec(i, j, minZ));
back.add(new Vec(i, j, maxZ));
});
CartesianProduct.product(stepsY, stepsZ).forEach(cross -> {
double j = (double) ((List<?>) cross).get(0);
double k = (double) ((List<?>) cross).get(1);
left.add(new Vec(minX, j, k));
right.add(new Vec(maxX, j, k));
});
CartesianProduct.product(stepsX, stepsZ).forEach(cross -> {
double i = (double) ((List<?>) cross).get(0);
double k = (double) ((List<?>) cross).get(1);
bottom.add(new Vec(i, minY, k));
top.add(new Vec(i, maxY, k));
});
// X -1 left | 1 right
// Y -1 bottom | 1 top
// Z -1 front | 1 back
var query = new HashMap<Vec, Vec[]>();
query.put(new Vec(0, 0, 0), new Vec[0]);
query.put(new Vec(-1, 0, 0), buildSet(left));
query.put(new Vec(1, 0, 0), buildSet(right));
query.put(new Vec(0, -1, 0), buildSet(bottom));
query.put(new Vec(0, 1, 0), buildSet(top));
query.put(new Vec(0, 0, -1), buildSet(front));
query.put(new Vec(0, 0, 1), buildSet(back));
query.put(new Vec(0, -1, -1), buildSet(bottom, front));
query.put(new Vec(0, -1, 1), buildSet(bottom, back));
query.put(new Vec(0, 1, -1), buildSet(top, front));
query.put(new Vec(0, 1, 1), buildSet(top, back));
query.put(new Vec(-1, -1, 0), buildSet(left, bottom));
query.put(new Vec(-1, 1, 0), buildSet(left, top));
query.put(new Vec(1, -1, 0), buildSet(right, bottom));
query.put(new Vec(1, 1, 0), buildSet(right, top));
query.put(new Vec(-1, 0, -1), buildSet(left, front));
query.put(new Vec(-1, 0, 1), buildSet(left, back));
query.put(new Vec(1, 0, -1), buildSet(right, front));
query.put(new Vec(1, 0, 1), buildSet(right, back));
query.put(new Vec(1, 1, 1), buildSet(right, top, back));
query.put(new Vec(1, 1, -1), buildSet(right, top, front));
query.put(new Vec(1, -1, 1), buildSet(right, bottom, back));
query.put(new Vec(1, -1, -1), buildSet(right, bottom, front));
query.put(new Vec(-1, 1, 1), buildSet(left, top, back));
query.put(new Vec(-1, 1, -1), buildSet(left, top, front));
query.put(new Vec(-1, -1, 1), buildSet(left, bottom, back));
query.put(new Vec(-1, -1, -1), buildSet(left, bottom, front));
return query;
}
}