Bezier interpolation

animationController.cpp

@@ -31,7 +31,7 @@ namespace vb01{
 
 				float ratio = (float)(max(0, currentFrame - pastFrame)) / (nextFrame - pastFrame);
 				Keyframe::Interpolation interp = pastKeyframe.interpolation;
-				float value = KeyframeChannel::interpolate(pastKeyframe.value, nextKeyframe.value, interp, ratio);
+				float value = KeyframeChannel::interpolate(pastKeyframe, nextKeyframe, ratio);
 				animatable->animate(value, keyframeChannel);
 			}
 		}

driver.cpp

@@ -22,7 +22,7 @@ namespace vb01{
 			ratio = 0;
 
 		Keyframe::Interpolation interp = pastKeyframe.interpolation;
-		float value = KeyframeChannel::interpolate(pastKeyframe.value, nextKeyframe.value, interp, ratio);
+		float value = KeyframeChannel::interpolate(pastKeyframe, nextKeyframe, ratio);
 		keyframeChannel.animatable->animate(value, keyframeChannel);
 	}
 

keyframeChannel.cpp

@@ -3,22 +3,34 @@
 using namespace std;
 
 namespace vb01{
-	float KeyframeChannel::interpolate(float pastValue, float nextValue, Keyframe::Interpolation mode, float ratio){
+	float KeyframeChannel::interpolate(Keyframe pastKeyframe, Keyframe nextKeyframe, float ratio){
 		float currentValue;
-		switch(mode){
+		switch(pastKeyframe.interpolation){
 			case Keyframe::CONSTANT:
-				currentValue = pastValue;
+				currentValue = pastKeyframe.value;
 				break;
 			case Keyframe::LINEAR:
-				currentValue = pastValue + (nextValue - pastValue) * ratio;
-				break;
 			case Keyframe::BEZIER:
-				currentValue = pastValue + (nextValue - pastValue) * ratio;
+				vector<float> points = vector<float>({pastKeyframe.value, pastKeyframe.rightHandleValue, nextKeyframe.leftHandleValue, nextKeyframe.value});
+				currentValue = interpolateBezier(points, ratio);
 				break;
 		}
 		return currentValue;
 	}
 
+	float KeyframeChannel::interpolateBezier(vector<float> points, float ratio){
+		int numPoints = points.size();
+		vector<float> newPoints;
+
+		for(int i = 0; i < numPoints - 1; i++)
+			newPoints.push_back(points[i] + (points[i + 1] - points[i]) * ratio);
+		
+		if(newPoints.size() >= 2)
+			return interpolateBezier(newPoints, ratio);
+		else
+			return newPoints[0];
+	}
+
 	KeyframeChannelType KeyframeChannel::getKeyframeChannelType(string typeString){
 		KeyframeChannelType type;
 		if(typeString == "pos_x")

keyframeChannel.h

@@ -26,7 +26,7 @@ namespace vb01{
 		struct Keyframe{
 			enum Interpolation{CONSTANT, LINEAR, BEZIER};
 
-			float value, frame;
+			float value, leftHandleValue, rightHandleValue, frame, leftHandleFrame, rightHandleFrame;
 			Interpolation interpolation;
 		};
 
@@ -34,8 +34,9 @@ namespace vb01{
 		Animatable *animatable = nullptr;
 		std::vector<Keyframe> keyframes;
 
+		static float interpolateBezier(std::vector<float>, float);
 		static KeyframeChannel::Type getKeyframeChannelType(std::string);
-		static float interpolate(float, float, Keyframe::Interpolation, float); 
+		static float interpolate(Keyframe, Keyframe, float); 
 		static Keyframe findKeyframe(float, KeyframeChannel, bool);
 		static void transform();
 	};

script.py

@@ -149,10 +149,12 @@ def getChannelType(channel):
 def readChannel(channel):
     channelType = getChannelType(channel)
 
-    for keyframe in channel.keyframe_points:
+    numKeyframes = len(channel.keyframe_points)
+    for i in range(numKeyframes):
+        keyframe = channel.keyframe_points[i]
         keyframeId = keyframe.co[0]
         interp = keyframe.interpolation
-        interpInt = - 1
+        interpInt = -1
 
         if interp == 'CONSTANT':
             interpInt = 0
@@ -163,9 +165,20 @@ def readChannel(channel):
 
         keyframeValue = keyframe.co[1]
         file.write(str(keyframeValue) + ' ' + str(keyframeId) + ' ' + str(interpInt))
-        if interp == 'BEZIER':
-            file.write(' ' + str(keyframe.handle_left.x) + ' ' + str(keyframe.handle_left.y) + ' ')
-            file.write(str(keyframe.handle_right.x) + ' ' + str(keyframe.handle_right.y) + ' ')
+
+        leftHandleValue = (keyframe.handle_left[1])
+        leftHandleFrame = (keyframe.handle_left[0])
+        rightHandleValue = (keyframe.handle_right[1])
+        rightHandleFrame = (keyframe.handle_right[0])
+        if interp != 'BEZIER':
+            rightHandleValue = keyframeValue
+            rightHandleFrame = keyframeId
+        if i > 0 and channel.keyframe_points[i - 1].interpolation != 'BEZIER':
+            leftHandleValue = keyframeValue
+            leftHandleFrame = keyframeId
+
+        file.write(' ' + str(leftHandleValue) + ' ' + str(leftHandleFrame) + ' ')
+        file.write(str(rightHandleValue) + ' ' + str(rightHandleFrame) + ' ')
         file.write('\n')
 
 def readDriver(channel, driverName):

vbModelReader.cpp

@@ -259,8 +259,12 @@ namespace vb01{
 
 			Keyframe keyframe;
 			keyframe.value = atof(keyframeData[0].c_str());
-			keyframe.frame = atoi(keyframeData[1].c_str());
+			keyframe.frame = atof(keyframeData[1].c_str());
 			keyframe.interpolation = (KeyframeInterpolation)atoi(keyframeData[2].c_str());
+			keyframe.leftHandleValue = atof(keyframeData[3].c_str());
+			keyframe.leftHandleFrame = atof(keyframeData[4].c_str());
+			keyframe.rightHandleValue = atof(keyframeData[5].c_str());
+			keyframe.rightHandleFrame = atof(keyframeData[6].c_str());
 			keyframeChannels[currentChannel].keyframes.push_back(keyframe);
 
 			numCurrentTypeKeyframes++;