Add Catmull-Rom spline interpolator to simplepathing

src/main/java/com/replaymod/simplepathing/InterpolatorType.java

@@ -1,5 +1,6 @@
 package com.replaymod.simplepathing;
 
+import com.replaymod.replaystudio.pathing.interpolation.CatmullRomSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.CubicSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.Interpolator;
 import com.replaymod.replaystudio.pathing.interpolation.LinearInterpolator;
@@ -11,6 +12,7 @@ import java.util.function.Supplier;
 @AllArgsConstructor
 public enum InterpolatorType {
     DEFAULT("default", null, null),
+    CATMULL_ROM("catmullrom", CatmullRomSplineInterpolator.class, () -> new CatmullRomSplineInterpolator(0.5)),
     CUBIC("cubic", CubicSplineInterpolator.class, CubicSplineInterpolator::new),
     LINEAR("linear", LinearInterpolator.class, LinearInterpolator::new);
 
@@ -34,7 +36,7 @@ public enum InterpolatorType {
         for (InterpolatorType t : values()) {
             if (t.getI18nName().equals(string)) return t;
         }
-        return CUBIC; //the default
+        return CATMULL_ROM; //the default
     }
 
     public static InterpolatorType fromClass(Class<? extends Interpolator> cls) {

src/main/java/com/replaymod/simplepathing/SPTimeline.java

@@ -2,6 +2,8 @@ package com.replaymod.simplepathing;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.Iterables;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonWriter;
 import com.replaymod.pathing.properties.CameraProperties;
@@ -14,6 +16,7 @@ import com.replaymod.replaystudio.pathing.change.CombinedChange;
 import com.replaymod.replaystudio.pathing.change.SetInterpolator;
 import com.replaymod.replaystudio.pathing.change.UpdateKeyframeProperties;
 import com.replaymod.replaystudio.pathing.impl.TimelineImpl;
+import com.replaymod.replaystudio.pathing.interpolation.CatmullRomSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.CubicSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.Interpolator;
 import com.replaymod.replaystudio.pathing.interpolation.LinearInterpolator;
@@ -68,7 +71,7 @@ public class SPTimeline implements PathingRegistry {
 
     @Getter
     private EntityPositionTracker entityTracker;
-    private InterpolatorType defaultInterpolatorType = InterpolatorType.CUBIC;
+    private InterpolatorType defaultInterpolatorType = InterpolatorType.fromString("invalid string returns default");
 
     public SPTimeline() {
         this(createInitialTimeline());
@@ -573,6 +576,11 @@ public class SPTimeline implements PathingRegistry {
             writer.value("linear");
         } else if (interpolator instanceof CubicSplineInterpolator) {
             writer.value("cubic-spline");
+        } else if (interpolator instanceof CatmullRomSplineInterpolator) {
+            writer.beginObject();
+            writer.name("type").value("catmull-rom-spline");
+            writer.name("alpha").value(((CatmullRomSplineInterpolator) interpolator).getAlpha());
+            writer.endObject();
         } else {
             throw new IOException("Unknown interpolator type: " + interpolator);
         }
@@ -580,12 +588,30 @@ public class SPTimeline implements PathingRegistry {
 
     @Override
     public Interpolator deserializeInterpolator(JsonReader reader) throws IOException {
-        String type = reader.nextString();
+        String type;
+        JsonObject args;
+        switch (reader.peek()) {
+            case STRING:
+                type = reader.nextString();
+                args = null;
+                break;
+            case BEGIN_OBJECT:
+                args = new JsonParser().parse(reader).getAsJsonObject();
+                type = args.get("type").getAsString();
+                break;
+            default:
+                throw new IOException("Unexpected token: " + reader.peek());
+        }
         switch (type) {
             case "linear":
                 return new LinearInterpolator();
             case "cubic-spline":
                 return new CubicSplineInterpolator();
+            case "catmull-rom-spline":
+                if (args == null || !args.has("alpha")) {
+                    throw new IOException("Missing alpha value for catmull-rom-spline.");
+                }
+                return new CatmullRomSplineInterpolator(args.get("alpha").getAsDouble());
             default:
                 throw new IOException("Unknown interpolation type: " + type);
 

src/main/java/com/replaymod/simplepathing/gui/GuiEditKeyframe.java

@@ -5,6 +5,7 @@ import com.replaymod.pathing.properties.TimestampProperty;
 import com.replaymod.replay.ReplayModReplay;
 import com.replaymod.replaystudio.pathing.change.Change;
 import com.replaymod.replaystudio.pathing.change.CombinedChange;
+import com.replaymod.replaystudio.pathing.interpolation.CatmullRomSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.CubicSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.Interpolator;
 import com.replaymod.replaystudio.pathing.interpolation.LinearInterpolator;
@@ -317,6 +318,9 @@ public abstract class GuiEditKeyframe<T extends GuiEditKeyframe<T>> extends Abst
                 removeElement(this.settingsPanel);
 
                 switch (getInterpolatorTypeNoDefault(type)) {
+                    case CATMULL_ROM:
+                        settingsPanel = new CatmullRomSettingsPanel();
+                        break;
                     case CUBIC:
                         settingsPanel = new CubicSettingsPanel();
                         break;
@@ -353,6 +357,33 @@ public abstract class GuiEditKeyframe<T extends GuiEditKeyframe<T>> extends Abst
                 public abstract I createInterpolator();
             }
 
+            public class CatmullRomSettingsPanel extends SettingsPanel<CatmullRomSplineInterpolator, CatmullRomSettingsPanel> {
+                public final GuiLabel alphaLabel = new GuiLabel().setColor(Colors.BLACK)
+                        .setI18nText("replaymod.gui.editkeyframe.interpolator.catmullrom.alpha");
+                public final GuiNumberField alphaField = new GuiNumberField().setSize(100, 20).setPrecision(5)
+                        .setMinValue(0).setValidateOnFocusChange(true);
+
+                {
+                    setLayout(new HorizontalLayout(HorizontalLayout.Alignment.CENTER));
+                    addElements(new HorizontalLayout.Data(0.5), alphaLabel, alphaField);
+                }
+
+                @Override
+                public void loadSettings(CatmullRomSplineInterpolator interpolator) {
+                    alphaField.setValue(interpolator.getAlpha());
+                }
+
+                @Override
+                public CatmullRomSplineInterpolator createInterpolator() {
+                    return new CatmullRomSplineInterpolator(alphaField.getDouble());
+                }
+
+                @Override
+                protected CatmullRomSettingsPanel getThis() {
+                    return this;
+                }
+            }
+
             public class CubicSettingsPanel extends SettingsPanel<CubicSplineInterpolator, CubicSettingsPanel> {
 
                 @Override

src/main/resources/assets/replaymod/lang/en_US.lang

@@ -292,6 +292,7 @@ replaymod.gui.settings.title=Replay Mod Settings
 
 replaymod.gui.settings.interpolation.linear=Linear
 replaymod.gui.settings.interpolation.cubic=Cubic
+replaymod.gui.settings.interpolation.catmullrom=Catmull Rom
 
 replaymod.gui.settings.bitrate=Video Bitrate
 replaymod.gui.settings.framerate=Video Framerate
@@ -376,6 +377,9 @@ replaymod.gui.editkeyframe.spec.method.shoulder.smoothness=Path Smoothness
 replaymod.gui.editkeyframe.interpolator=Interpolator
 replaymod.gui.editkeyframe.interpolator.default.name=Default Interpolator
 replaymod.gui.editkeyframe.interpolator.default.desc=Uses the default interpolator defined in the Replay Mod Settings.
+replaymod.gui.editkeyframe.interpolator.catmullrom.name=Catmull Rom Spline Interpolator
+replaymod.gui.editkeyframe.interpolator.catmullrom.desc=Calculates a catmull rom spline with customizable alpha value for precise tightness and smoothness of the camera path.
+replaymod.gui.editkeyframe.interpolator.catmullrom.alpha=Alpha:
 replaymod.gui.editkeyframe.interpolator.cubic.name=Cubic Spline Interpolator
 replaymod.gui.editkeyframe.interpolator.cubic.desc=Calculates a cubic equation matrix for all points for a smooth camera path.
 replaymod.gui.editkeyframe.interpolator.linear.name=Linear Interpolator

src/test/java/com/replaymod/simplepathing/SPTimelineTest.java

@@ -5,6 +5,7 @@ import com.replaymod.pathing.properties.CameraProperties;
 import com.replaymod.pathing.properties.SpectatorProperty;
 import com.replaymod.pathing.properties.TimestampProperty;
 import com.replaymod.replaystudio.pathing.change.Change;
+import com.replaymod.replaystudio.pathing.interpolation.CatmullRomSplineInterpolator;
 import com.replaymod.replaystudio.pathing.interpolation.Interpolator;
 import com.replaymod.replaystudio.pathing.interpolation.LinearInterpolator;
 import com.replaymod.replaystudio.pathing.path.Keyframe;
@@ -510,6 +511,37 @@ public class SPTimelineTest {
         assertValidInterpolators(SPPath.POSITION, 4);
     }
 
+    @Test(expected = IllegalArgumentException.class)
+    public void testSetDefaultInterpolatorDifferentType() {
+        addPosition(0, 0);
+        addPosition(1, 1);
+        impl.setDefaultInterpolator(new CatmullRomSplineInterpolator(42));
+    }
+
+    @Test
+    public void testSetDefaultInterpolatorSameType() {
+        impl.setDefaultInterpolatorType(InterpolatorType.CATMULL_ROM);
+        addPosition(0, 0);
+        addSpectator(1, 1);
+        addSpectator(2, 2);
+        addPosition(3, 3);
+        addPosition(4, 3);
+        impl.setDefaultInterpolator(new CatmullRomSplineInterpolator(42));
+        assertValidInterpolators(SPPath.POSITION, 3);
+        assertIsCatmullRom(0, 42);
+        assertIsCatmullRom(2, 42);
+        assertIsCatmullRom(3, 42);
+    }
+
+    private void assertIsCatmullRom(int index, double alpha) {
+        String str = prettyPrintInterpolators(impl, SPPath.POSITION);
+        Interpolator interpolator = Iterables.get(impl.getPositionPath().getSegments(), index).getInterpolator();
+        assertTrue("Expected segment " + index + " to be catmull rom interpolator: " + str,
+                 interpolator instanceof CatmullRomSplineInterpolator);
+        assertTrue("Expected interpolator of segment segment " + index + " to have alpha " + alpha + ": " + str,
+                ((CatmullRomSplineInterpolator) interpolator).getAlpha() == 42);
+    }
+
     private void addPosition(int time, int expectedNumberOfInterpolators) {
         impl.addPositionKeyframe(time, 1, 2, 3, 4, 5, 6, -1);
         assertNotNull(impl.getKeyframe(SPPath.POSITION, time));