Move bicubic point interpolation logic to SplineCurve

Originally committed to SVN as r6592.

aegisub/src/spline.cpp

@@ -196,24 +196,6 @@ void Spline::MovePoint(iterator curve,int point,Vector2D pos) {
 	}
 }
 
-static int render_bicubic(Spline::iterator cur, std::vector<float> &points) {
-	int len = int(
-		(cur->p2 - cur->p1).Len() +
-		(cur->p3 - cur->p2).Len() +
-		(cur->p4 - cur->p3).Len());
-	int steps = len/8;
-
-	for (int i = 0; i <= steps; ++i) {
-		// Get t and t-1 (u)
-		float t = i / float(steps);
-		Vector2D p = cur->GetPoint(t);
-		points.push_back(p.X());
-		points.push_back(p.Y());
-	}
-
-	return steps + 1;
-}
-
 void Spline::GetPointList(std::vector<float>& points, std::vector<int>& first, std::vector<int>& count) {
 	points.clear();
 	first.clear();
@@ -224,30 +206,15 @@ void Spline::GetPointList(std::vector<float>& points, std::vector<int>& first, s
 
 	// Generate points for each curve
 	for (iterator cur = begin(); cur != end(); ++cur) {
-		switch (cur->type) {
-			case SplineCurve::POINT:
-				if (curCount > 0)
-					count.push_back(curCount);
+		if (cur->type == SplineCurve::POINT) {
+			if (curCount > 0)
+				count.push_back(curCount);
 
-				// start new path
-				first.push_back(points.size() / 2);
-				points.push_back(cur->p1.X());
-				points.push_back(cur->p1.Y());
-				curCount = 1;
-				break;
-
-			case SplineCurve::LINE:
-				points.push_back(cur->p2.X());
-				points.push_back(cur->p2.Y());
-				++curCount;
-				break;
-
-			case SplineCurve::BICUBIC:
-				curCount += render_bicubic(cur, points);
-				break;
-
-			default: break;
+			// start new path
+			first.push_back(points.size() / 2);
+			curCount = 0;
 		}
+		curCount += cur->GetPoints(points);
 	}
 
 	count.push_back(curCount);
@@ -265,7 +232,7 @@ void Spline::GetPointList(std::vector<float> &points, iterator curve) {
 			break;
 
 		case SplineCurve::BICUBIC:
-			render_bicubic(curve, points);
+			curve->GetPoints(points);
 			break;
 
 		default: break;

aegisub/src/spline_curve.cpp

@@ -169,3 +169,38 @@ float SplineCurve::GetClosestSegmentDistance(Vector2D pt1, Vector2D pt2, Vector2
 	float t = GetClosestSegmentPart(pt1, pt2, pt3);
 	return (pt1 * (1.f - t) + pt2 * t - pt3).Len();
 }
+
+int SplineCurve::GetPoints(std::vector<float> &points) const {
+	switch (type) {
+		case POINT:
+			points.push_back(p1.X());
+			points.push_back(p1.Y());
+			return 1;
+
+		case LINE:
+			points.push_back(p2.X());
+			points.push_back(p2.Y());
+			return 1;
+
+		case BICUBIC: {
+			int len = int(
+				(p2 - p1).Len() +
+				(p3 - p2).Len() +
+				(p4 - p3).Len());
+			int steps = len/8;
+
+			for (int i = 0; i <= steps; ++i) {
+				// Get t and t-1 (u)
+				float t = i / float(steps);
+				Vector2D p = GetPoint(t);
+				points.push_back(p.X());
+				points.push_back(p.Y());
+			}
+
+			return steps + 1;
+		}
+
+		default:
+			return 0;
+	}
+}

aegisub/src/spline_curve.h

@@ -36,6 +36,10 @@
 
 #include "vector2d.h"
 
+#ifndef AGI_PRE
+#include <vector>
+#endif
+
 /// DOCME
 /// @class SplineCurve
 /// @brief DOCME
@@ -83,4 +87,9 @@ public:
 	float GetClosestParam(Vector2D ref) const;
 	/// Get distance from ref to the closest point on the curve
 	float GetQuickDistance(Vector2D ref) const;
+
+	/// Get the coordinates of each point on this curve
+	/// @param[out] points Vector to add points to
+	/// @return Number of points in the curve
+	int GetPoints(std::vector<float> &points) const;
 };