From 960c90988e0eabb2af9f00ea7701c1f41abd8817 Mon Sep 17 00:00:00 2001
From: Soeren Peters <peters@irmb.tu-bs.de>
Date: Wed, 19 Jan 2022 11:57:49 +0100
Subject: [PATCH] Add bezier solution with bernstein polynom.
---
README.md | 12 +++++++-
.../java/irmb/flowsim/model/BezierCurve.java | 22 ++++++++++----
.../view/graphics/PaintableBezierCurve.java | 29 +++++++++++++++++--
3 files changed, 54 insertions(+), 9 deletions(-)
diff --git a/README.md b/README.md
index 77cc73a..68b240f 100644
--- a/README.md
+++ b/README.md
@@ -64,4 +64,14 @@ Compared to the last exercise, we now have the following folder filled with clas
The task is implement BuildObjectMouseStrategy and MoveMouseStrategy.
### Expected behavior:
-Shapes can be painted via the menu or the toolbar. Additionally, the shapes can be moved via the mouse, the window can be panned and zoomed. A right click should remove the shape.
\ No newline at end of file
+Shapes can be painted via the menu or the toolbar. Additionally, the shapes can be moved via the mouse, the window can be panned and zoomed. A right click should remove the shape.
+
+## Exercuse 5
+This exercise is based on the eighth lecture about the bezier interpolation method.
+Compared to the last exercise, we now have the following folder filled with class stubs.
+
+ model/BezierCurve.java
+ view/graphics/PaintableBezierCurve.java
+
+### Expected behavior:
+Bezier Curve can be painted.
diff --git a/src/main/java/irmb/flowsim/model/BezierCurve.java b/src/main/java/irmb/flowsim/model/BezierCurve.java
index ac5a0b4..01b5802 100644
--- a/src/main/java/irmb/flowsim/model/BezierCurve.java
+++ b/src/main/java/irmb/flowsim/model/BezierCurve.java
@@ -12,17 +12,27 @@ public class BezierCurve extends PolyLine {
public Point calculatePointWithBernstein(double t) {
- //TODO
- return new Point(0,0);
+ List<Point> pointList = getPointList();
+ int size = pointList.size();
+ double x = 0, y = 0;
+ for (int i = 0; i < size; i++) {
+ double c = binomialCoefficient(size - 1, i) * Math.pow(t, i) * Math.pow(1.0 - t, size - 1.0 - i);
+ x += c * pointList.get(i).getX();
+ y += c * pointList.get(i).getY();
+ }
+ return new Point(x, y);
}
private double binomialCoefficient(int n, int k) {
- //TODO
- return 0.0;
+ if (n >= k && n >= 0)
+ return factorial(n) / (double)(factorial(k) * factorial(n - k));
+ return -1;
}
private long factorial(int n) {
- //TODO
- return 0;
+ long sum = 1;
+ for (int i = n; i >= 1; i--)
+ sum *= i;
+ return sum;
}
}
diff --git a/src/main/java/irmb/flowsim/view/graphics/PaintableBezierCurve.java b/src/main/java/irmb/flowsim/view/graphics/PaintableBezierCurve.java
index d35dd07..2a0f669 100644
--- a/src/main/java/irmb/flowsim/view/graphics/PaintableBezierCurve.java
+++ b/src/main/java/irmb/flowsim/view/graphics/PaintableBezierCurve.java
@@ -23,12 +23,37 @@ public class PaintableBezierCurve extends PaintableShape {
@Override
public void paint(Painter painter) {
- //TODO
+ List<Point> pointList = bezierCurve.getPointList();
+ int numOfPoints = 100;
+ if (pointList.size() >= 2) {
+ for (int i = 0; i < numOfPoints-1; i++) {
+ double t1 = (i) / (double) (numOfPoints - 1);
+ double t2 = (i + 1.0) / (double) (numOfPoints - 1);
+
+ Point p1 = bezierCurve.calculatePointWithBernstein(t1);
+ Point p2 = bezierCurve.calculatePointWithBernstein(t2);
+
+ painter.paintLine(new Point(p1.getX(), p1.getY()), new Point(p2.getX(), p2.getY()));
+ }
+ }
}
@Override
public boolean isPointOnBoundary(Point point, double radius) {
- //TODO
+ if (getDefinedPoint(point, radius) != null)
+ return true;
+ int numPoints = 100;
+ for (int i = 0; i < numPoints - 1; i++) {
+ double t1, t2;
+ t1 = i / (double) (numPoints - 1);
+ t2 = (i + 1) / (double) (numPoints - 1);
+ first = bezierCurve.calculatePointWithBernstein(t1);
+ second = bezierCurve.calculatePointWithBernstein(t2);
+ if (isInXBounds(point)) {
+ double distanceToLine = getDistanceToLine(first, second, point);
+ if (distanceToLine <= radius) return true;
+ }
+ }
return false;
}
--
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