-
Notifications
You must be signed in to change notification settings - Fork 3
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
feat(gui): use curves instead of straight lines
- Loading branch information
Showing
4 changed files
with
165 additions
and
5 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
98 changes: 98 additions & 0 deletions
98
urban-spork-client-gui/src/com/urbanspork/client/gui/spine/CatmullRom.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,98 @@ | ||
| package com.urbanspork.client.gui.spine; | ||
|
|
||
| import javafx.geometry.Point2D; | ||
|
|
||
| /** | ||
| * Java implement of <a href="https://en.wikipedia.org/wiki/Centripetal_Catmull–Rom_spline">Centripetal Catmull–Rom spline</a> | ||
| * | ||
| * @param alpha The alpha value ranges from 0 to 1 | ||
| * <ul> | ||
| * <li>0.5 for the centripetal spline | ||
| * <li>0.0 for the uniform spline | ||
| * <li>1.0 for the chordal spline | ||
| * </ul> | ||
| * @author Zmax0 | ||
| */ | ||
| public record CatmullRom(double alpha) { | ||
| /** | ||
| * Calculate Catmull-Rom for a sequence of initial points and return the combined curve. | ||
| * | ||
| * @param points Base points from which the quadruples for the algorithm are taken | ||
| * @param segment The number of points include in each curve segment | ||
| * @return The combined curve | ||
| */ | ||
| public Point2D[] interpolate(Point2D[] points, int segment) { | ||
| if (points.length < 2) { | ||
| throw new IllegalArgumentException("The points parameter must be greater than 2"); | ||
| } | ||
| if (points.length < 3) { | ||
| return points; | ||
| } | ||
| Point2D[] controls = getControls(points); | ||
| Point2D[] curve = new Point2D[points.length + (points.length - 1) * segment]; | ||
| for (int i = 0; i < controls.length - 3; i++) { | ||
| curve[i * (segment + 1)] = controls[i + 1]; | ||
| Point2D[] temp = interpolate(controls[i], controls[i + 1], controls[i + 2], controls[i + 3], segment); | ||
| System.arraycopy(temp, 0, curve, i * (segment + 1) + 1, segment); | ||
| } | ||
| curve[curve.length - 1] = (controls[controls.length - 2]); // last | ||
| return curve; | ||
| } | ||
|
|
||
| private Point2D[] getControls(Point2D[] point) { | ||
| Point2D[] controls = new Point2D[point.length + 2]; | ||
| System.arraycopy(point, 0, controls, 1, point.length); | ||
| // set two control points at start C1 and end C2 | ||
| if (point[0].equals(point[point.length - 1])) { // if is close | ||
| // C1 = P(n-1) | ||
| controls[0] = point[point.length - 2]; | ||
| // C2 = P1 | ||
| controls[controls.length - 1] = point[1]; | ||
| } else { | ||
| // C1 = P0 - (P1 - P0) | ||
| controls[0] = point[0].subtract(point[1].subtract(point[0])); | ||
| // C2 = Pn + (Pn - P(n-1)) | ||
| controls[controls.length - 1] = point[point.length - 1].add(point[point.length - 1].subtract(point[point.length - 2])); | ||
| } | ||
| return controls; | ||
| } | ||
|
|
||
| /** | ||
| * Calculate Catmull-Rom spline curve points starts with p1 and ends with p2 | ||
| * | ||
| * @param p0 The (x,y) point pairs that define the Catmull-Rom spline | ||
| * @param p1 The (x,y) point pairs that define the Catmull-Rom spline | ||
| * @param p2 The (x,y) point pairs that define the Catmull-Rom spline | ||
| * @param p3 The (x,y) point pairs that define the Catmull-Rom spline | ||
| * @param segment The number of points to include in each curve segment | ||
| * @return points for the resulting curve | ||
| */ | ||
| public Point2D[] interpolate(Point2D p0, Point2D p1, Point2D p2, Point2D p3, int segment) { | ||
| // calculate knots | ||
| double t0 = 0; | ||
| double t1 = getT(t0, p0, p1); | ||
| double t2 = getT(t1, p1, p2); | ||
| double t3 = getT(t2, p2, p3); | ||
| double step = (t2 - t1) / (segment - 1); | ||
| // evaluate the point | ||
| Point2D[] curve = new Point2D[segment]; | ||
| curve[0] = p1; | ||
| for (int i = 1; i < segment - 1; i++) { | ||
| double t = t1 + i * step; | ||
| Point2D a1 = p0.multiply((t1 - t) / (t1 - t0)).add(p1.multiply((t - t0) / (t1 - t0))); | ||
| Point2D a2 = p1.multiply((t2 - t) / (t2 - t1)).add(p2.multiply((t - t1) / (t2 - t1))); | ||
| Point2D a3 = p2.multiply((t3 - t) / (t3 - t2)).add(p3.multiply((t - t2) / (t3 - t2))); | ||
| Point2D b1 = a1.multiply((t2 - t) / (t2 - t0)).add(a2.multiply((t - t0) / (t2 - t0))); | ||
| Point2D b2 = a2.multiply((t3 - t) / (t3 - t1)).add(a3.multiply((t - t1) / (t3 - t1))); | ||
| curve[i] = b1.multiply((t2 - t) / (t2 - t1)).add(b2.multiply((t - t1) / (t2 - t1))); | ||
| } | ||
| curve[curve.length - 1] = p2; | ||
| return curve; | ||
| } | ||
|
|
||
| // calculate knots | ||
| private double getT(double t, Point2D p0, Point2D p1) { | ||
| Point2D d = p1.subtract(p0); | ||
| return Math.pow(d.dotProduct(d), alpha * .5) + t; | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters