1 files changed, 50 insertions, 0 deletions
diff --git a/bezier.cpp b/bezier.cpp
index 4e0cb5c..77aa18c 100644
--- a/bezier.cpp
+++ b/bezier.cpp
@@ -155,3 +155,53 @@ void Bezier_CubicCalcPoints(v2 p1, v2 p2, v2 p3, v2 p4, void *Data, uint32 *Incr
     void *Pointer = Data;
     Bezier_CubicCalcPointsCasteljauStep(Pointer, Increment, p1.x, p1.y, p2.x, p2.y, p3.x, p3.y, p4.x, p4.y, tess_tol, 0);
 }
+
+// These functions will become more generalized as shapes are added.
+
+static void
+Mask_AddPointToLine(mask *Mask, uint16 Index, v2 Pos)
+{
+    for (int i = Mask->NumberOfPoints - 1; i > Index; i--) {
+        Mask->Point[i+1] = Mask->Point[i];
+    }
+    mask_point *PointToAdd = &Mask->Point[Index+1];
+    PointToAdd->Pos = Pos;
+    Mask->NumberOfPoints++;
+}
+
+static void
+Mask_PushPoint(mask *Mask, v2 Pos)
+{
+    mask_point *PointToAdd = &Mask->Point[Mask->NumberOfPoints];
+    PointToAdd->Pos = Pos;
+    Mask->NumberOfPoints++;
+}
+
+static void
+Mask_AddPointToCurve(mask *Mask, uint16 Index, real32 ratio)
+{
+    mask_point *Point0 = &Mask->Point[Index];
+    mask_point *Point1 = &Mask->Point[Index+1];
+
+    v2 Point0_Pos_Right = Point0->Pos + Point0->TangentRight;
+    v2 Point1_Pos_Left = Point1->Pos + Point1->TangentLeft;
+    v2 Handle0_Half   = Line_RatioToPoint(Point0->Pos,      Point0_Pos_Right, ratio);
+    v2 Handle1_Half   = Line_RatioToPoint(Point1_Pos_Left,  Point1->Pos,      ratio);
+    v2 Top_Half       = Line_RatioToPoint(Point0_Pos_Right, Point1_Pos_Left,  ratio);
+    v2 NewHandleLeft  = Line_RatioToPoint(Handle0_Half,     Top_Half,         ratio);
+    v2 NewHandleRight = Line_RatioToPoint(Top_Half,         Handle1_Half,     ratio);
+    v2 NewPos         = Line_RatioToPoint(NewHandleLeft,    NewHandleRight,   ratio);
+
+    Point0->TangentRight = -(Point0->Pos - Handle0_Half);
+    Point1->TangentLeft  = -(Point1->Pos - Handle1_Half);
+
+    for (int i = Mask->NumberOfPoints - 1; i > Index; i--) {
+        Mask->Point[i+1] = Mask->Point[i];
+    }
+    mask_point *PointToAdd = &Mask->Point[Index+1];
+
+    PointToAdd->Pos = NewPos;
+    PointToAdd->TangentLeft  = -(NewPos - NewHandleLeft);
+    PointToAdd->TangentRight = -(NewPos - NewHandleRight);
+    Mask->NumberOfPoints++;
+}