diff options
Diffstat (limited to 'src/jogl/classes/com/jogamp/math/VectorUtil.java')
-rw-r--r-- | src/jogl/classes/com/jogamp/math/VectorUtil.java | 56 |
1 files changed, 45 insertions, 11 deletions
diff --git a/src/jogl/classes/com/jogamp/math/VectorUtil.java b/src/jogl/classes/com/jogamp/math/VectorUtil.java index 716b63e47..7e66f0b4f 100644 --- a/src/jogl/classes/com/jogamp/math/VectorUtil.java +++ b/src/jogl/classes/com/jogamp/math/VectorUtil.java @@ -537,7 +537,7 @@ public final class VectorUtil { /** * Check if points are in ccw order * <p> - * Consider using {@link #getWinding(ArrayList)} using the {@link #area(ArrayList)} function over all points + * Consider using {@link #getWinding2f(ArrayList)} using the {@link #area2f(ArrayList)} function over all points * on complex shapes for a reliable result! * </p> * @param a first vertex @@ -552,29 +552,29 @@ public final class VectorUtil { /** * Compute the winding of the 3 given points * <p> - * Consider using {@link #getWinding(ArrayList)} using the {@link #area(ArrayList)} function over all points + * Consider using {@link #getWinding2f(ArrayList)} using the {@link #area2f(ArrayList)} function over all points * on complex shapes for a reliable result! * </p> * @param a first vertex * @param b second vertex * @param c third vertex * @return {@link Winding#CCW} or {@link Winding#CW} - * @see #getWinding(ArrayList) + * @see #getWinding2f(ArrayList) */ public static Winding getWinding(final Vert2fImmutable a, final Vert2fImmutable b, final Vert2fImmutable c) { return triAreaVec2d(a,b,c) > InCircleDThreshold ? Winding.CCW : Winding.CW ; } /** - * Computes the area of a list of vertices. + * Computes the area of a list of vertices via shoelace formula. * <p> * This method is utilized e.g. to reliably compute the {@link Winding} of complex shapes. * </p> * @param vertices * @return positive area if ccw else negative area value - * @see #getWinding(ArrayList) + * @see #getWinding2f(ArrayList) */ - public static float area(final ArrayList<? extends Vert2fImmutable> vertices) { + public static float area2f(final ArrayList<? extends Vert2fImmutable> vertices) { final int n = vertices.size(); float area = 0.0f; for (int p = n - 1, q = 0; q < n; p = q++) { @@ -586,17 +586,51 @@ public final class VectorUtil { } /** - * Compute the winding using the {@link #area(ArrayList)} function over all vertices for complex shapes. + * Compute the winding using the {@link #area2f(ArrayList)} function over all vertices for complex shapes. * <p> - * Uses the {@link #area(ArrayList)} function over all points + * Uses the {@link #area2f(ArrayList)} function over all points * on complex shapes for a reliable result! * </p> * @param vertices array of Vertices * @return {@link Winding#CCW} or {@link Winding#CW} - * @see #area(ArrayList) + * @see #area2f(ArrayList) */ - public static Winding getWinding(final ArrayList<? extends Vert2fImmutable> vertices) { - return area(vertices) >= 0 ? Winding.CCW : Winding.CW ; + public static Winding getWinding2f(final ArrayList<? extends Vert2fImmutable> vertices) { + return area2f(vertices) >= 0 ? Winding.CCW : Winding.CW ; + } + + /** + * Computes the area of a list of vertices via shoelace formula. + * <p> + * This method is utilized e.g. to reliably compute the {@link Winding} of complex shapes. + * </p> + * @param vertices + * @return positive area if ccw else negative area value + * @see #getWinding2d(ArrayList) + */ + public static double area2d(final ArrayList<? extends Vert2fImmutable> vertices) { + final int n = vertices.size(); + double area = 0.0; + for (int p = n - 1, q = 0; q < n; p = q++) { + final Vert2fImmutable pCoord = vertices.get(p); + final Vert2fImmutable qCoord = vertices.get(q); + area += (double)pCoord.x() * (double)qCoord.y() - (double)qCoord.x() * (double)pCoord.y(); + } + return area; + } + + /** + * Compute the winding using the {@link #area2f(ArrayList)} function over all vertices for complex shapes. + * <p> + * Uses the {@link #area2f(ArrayList)} function over all points + * on complex shapes for a reliable result! + * </p> + * @param vertices array of Vertices + * @return {@link Winding#CCW} or {@link Winding#CW} + * @see #area2d(ArrayList) + */ + public static Winding getWinding2d(final ArrayList<? extends Vert2fImmutable> vertices) { + return area2d(vertices) >= 0 ? Winding.CCW : Winding.CW ; } /** |