/*
* Copyright 2013 MovingBlocks
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.terasology.math;
import com.google.common.base.Objects;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import gnu.trove.map.TByteObjectMap;
import gnu.trove.map.hash.TByteObjectHashMap;
import org.terasology.math.geom.Quat4f;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Rotation provides easy access to 90 degree increments of rotations - intended for block-related rotations.
* <br><br>
* Uses the fly weight pattern to cache the 64 combinations of rotation.
* Note (Marcin Sciesinski): there are actually only 24 possible combinations, the remaining 40 are just duplicates
*
*/
public final class Rotation {
private static final TByteObjectMap<Rotation> ALL_ROTATIONS;
private static final TByteObjectMap<Rotation> NORMALIZED_ROTATIONS;
private static final ImmutableList<Rotation> HORIZONTAL_ROTATIONS;
private static final Map<Rotation, Rotation> REVERSE_ROTATIONS_MAP;
private Yaw yaw;
private Pitch pitch;
private Roll roll;
private Rotation(Yaw yaw, Pitch pitch, Roll roll) {
this.pitch = pitch;
this.yaw = yaw;
this.roll = roll;
}
public static Rotation none() {
return ALL_ROTATIONS.get(indexFor(Yaw.NONE, Pitch.NONE, Roll.NONE));
}
public static Rotation rotate(Pitch pitch) {
return ALL_ROTATIONS.get(indexFor(Yaw.NONE, pitch, Roll.NONE));
}
public static Rotation rotate(Yaw yaw) {
return ALL_ROTATIONS.get(indexFor(yaw, Pitch.NONE, Roll.NONE));
}
public static Rotation rotate(Roll roll) {
return ALL_ROTATIONS.get(indexFor(Yaw.NONE, Pitch.NONE, roll));
}
public static Rotation rotate(Yaw yaw, Pitch pitch) {
return ALL_ROTATIONS.get(indexFor(yaw, pitch, Roll.NONE));
}
public static Rotation rotate(Pitch pitch, Roll roll) {
return ALL_ROTATIONS.get(indexFor(Yaw.NONE, pitch, roll));
}
public static Rotation rotate(Yaw yaw, Roll roll) {
return ALL_ROTATIONS.get(indexFor(yaw, Pitch.NONE, roll));
}
public static Rotation rotate(Yaw yaw, Pitch pitch, Roll roll) {
return ALL_ROTATIONS.get(indexFor(yaw, pitch, roll));
}
/**
* Finds a reverse rotation to the specified one. Any side transformed by the rotation passed as a parameter, when
* passed to the returned rotation will return the original Side.
*
* @param rotation Rotation to find reverse rotation to.
*
* @return Reverse rotation to the specified one.
*/
public static Rotation findReverse(Rotation rotation) {
Preconditions.checkNotNull(rotation);
return REVERSE_ROTATIONS_MAP.get(rotation);
}
public static List<Rotation> horizontalRotations() {
return HORIZONTAL_ROTATIONS;
}
static {
ALL_ROTATIONS = new TByteObjectHashMap<>();
NORMALIZED_ROTATIONS = new TByteObjectHashMap<>();
for (Pitch pitch : Pitch.values()) {
for (Yaw yaw : Yaw.values()) {
for (Roll roll : Roll.values()) {
Rotation rotation = new Rotation(yaw, pitch, roll);
ALL_ROTATIONS.put(indexFor(yaw, pitch, roll), new Rotation(yaw, pitch, roll));
Byte duplicateIndex = findDuplicateRotation(rotation);
if (duplicateIndex == null) {
NORMALIZED_ROTATIONS.put(indexFor(yaw, pitch, roll), rotation);
}
}
}
}
HORIZONTAL_ROTATIONS = ImmutableList.of(
ALL_ROTATIONS.get(indexFor(Yaw.NONE, Pitch.NONE, Roll.NONE)),
ALL_ROTATIONS.get(indexFor(Yaw.CLOCKWISE_90, Pitch.NONE, Roll.NONE)),
ALL_ROTATIONS.get(indexFor(Yaw.CLOCKWISE_180, Pitch.NONE, Roll.NONE)),
ALL_ROTATIONS.get(indexFor(Yaw.CLOCKWISE_270, Pitch.NONE, Roll.NONE)));
REVERSE_ROTATIONS_MAP = new HashMap<>();
for (Rotation rotation : ALL_ROTATIONS.valueCollection()) {
Rotation reverse = findReverseInternal(rotation);
REVERSE_ROTATIONS_MAP.put(rotation, reverse);
}
}
private static Rotation findReverseInternal(Rotation rotation) {
Side frontResult = rotation.rotate(Side.FRONT);
Side topResult = rotation.rotate(Side.TOP);
for (Rotation possibility : values()) {
if (possibility.rotate(frontResult) == Side.FRONT
&& possibility.rotate(topResult) == Side.TOP) {
return possibility;
}
}
throw new RuntimeException("Unable to find reverse rotation");
}
private static Byte findDuplicateRotation(Rotation rotation) {
Side frontResult = rotation.rotate(Side.FRONT);
Side topResult = rotation.rotate(Side.TOP);
byte[] result = new byte[]{127};
NORMALIZED_ROTATIONS.forEachEntry(
(a, b) -> {
if (b.rotate(Side.FRONT) == frontResult
&& b.rotate(Side.TOP) == topResult) {
result[0] = a;
return false;
}
return true;
});
if (result[0] != 127) {
return result[0];
} else {
return null;
}
}
private static byte indexFor(Yaw yaw, Pitch pitch, Roll roll) {
return (byte) ((yaw.getIndex() << 4) + (pitch.getIndex() << 2) + roll.getIndex());
}
public Yaw getYaw() {
return yaw;
}
public Pitch getPitch() {
return pitch;
}
public Roll getRoll() {
return roll;
}
public Quat4f getQuat4f() {
Quat4f rotation = new Quat4f(yaw.getRadians(), pitch.getRadians(), roll.getRadians());
rotation.normalize();
return rotation;
}
public Side rotate(Side side) {
Side result = side;
result = result.rollClockwise(roll.getIncrements());
result = result.pitchClockwise(pitch.getIncrements());
result = result.yawClockwise(yaw.getIncrements());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj instanceof Rotation) {
Rotation other = (Rotation) obj;
return yaw == other.yaw && pitch == other.pitch && roll == other.roll;
}
return false;
}
@Override
public int hashCode() {
return Objects.hashCode(yaw, pitch, roll);
}
/**
* Returns all possible rotations for each yaw, pitch & roll combination, including duplicates.
*
* @return All possible rotations for each yaw, pitch & roll combination.
*/
public static Iterable<Rotation> allValues() {
return ALL_ROTATIONS.valueCollection();
}
/**
* Returns only unique rotations, in respect to transformations, rather than in respect to yaw, pitch & roll.
*
* @return Unique rotations, in respect to transformations.
*/
public static Iterable<Rotation> values() {
return NORMALIZED_ROTATIONS.valueCollection();
}
}