/******************************************************************************
* Spine Runtimes Software License v2.5
*
* Copyright (c) 2013-2016, Esoteric Software
* All rights reserved.
*
* You are granted a perpetual, non-exclusive, non-sublicensable, and
* non-transferable license to use, install, execute, and perform the Spine
* Runtimes software and derivative works solely for personal or internal
* use. Without the written permission of Esoteric Software (see Section 2 of
* the Spine Software License Agreement), you may not (a) modify, translate,
* adapt, or develop new applications using the Spine Runtimes or otherwise
* create derivative works or improvements of the Spine Runtimes or (b) remove,
* delete, alter, or obscure any trademarks or any copyright, trademark, patent,
* or other intellectual property or proprietary rights notices on or in the
* Software, including any copy thereof. Redistributions in binary or source
* form must include this license and terms.
*
* THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, BUSINESS INTERRUPTION, OR LOSS OF
* USE, DATA, OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*****************************************************************************/
package com.esotericsoftware.spine;
import com.badlogic.gdx.utils.Array;
import com.badlogic.gdx.utils.FloatArray;
import com.badlogic.gdx.utils.Pool;
import com.esotericsoftware.spine.attachments.Attachment;
import com.esotericsoftware.spine.attachments.BoundingBoxAttachment;
/** Collects each {@link BoundingBoxAttachment} that is visible and computes the world vertices for its polygon. The polygon
* vertices are provided along with convenience methods for doing hit detection. */
public class SkeletonBounds {
private float minX, minY, maxX, maxY;
private Array<BoundingBoxAttachment> boundingBoxes = new Array();
private Array<FloatArray> polygons = new Array();
private Pool<FloatArray> polygonPool = new Pool() {
protected Object newObject () {
return new FloatArray();
}
};
/** Clears any previous polygons, finds all visible bounding box attachments, and computes the world vertices for each bounding
* box's polygon.
* @param updateAabb If true, the axis aligned bounding box containing all the polygons is computed. If false, the
* SkeletonBounds AABB methods will always return true. */
public void update (Skeleton skeleton, boolean updateAabb) {
if (skeleton == null) throw new IllegalArgumentException("skeleton cannot be null.");
Array<BoundingBoxAttachment> boundingBoxes = this.boundingBoxes;
Array<FloatArray> polygons = this.polygons;
Array<Slot> slots = skeleton.slots;
int slotCount = slots.size;
boundingBoxes.clear();
polygonPool.freeAll(polygons);
polygons.clear();
for (int i = 0; i < slotCount; i++) {
Slot slot = slots.get(i);
Attachment attachment = slot.attachment;
if (attachment instanceof BoundingBoxAttachment) {
BoundingBoxAttachment boundingBox = (BoundingBoxAttachment)attachment;
boundingBoxes.add(boundingBox);
FloatArray polygon = polygonPool.obtain();
polygons.add(polygon);
boundingBox.computeWorldVertices(slot, polygon.setSize(boundingBox.getWorldVerticesLength()));
}
}
if (updateAabb)
aabbCompute();
else {
minX = Integer.MIN_VALUE;
minY = Integer.MIN_VALUE;
maxX = Integer.MAX_VALUE;
maxY = Integer.MAX_VALUE;
}
}
private void aabbCompute () {
float minX = Integer.MAX_VALUE, minY = Integer.MAX_VALUE, maxX = Integer.MIN_VALUE, maxY = Integer.MIN_VALUE;
Array<FloatArray> polygons = this.polygons;
for (int i = 0, n = polygons.size; i < n; i++) {
FloatArray polygon = polygons.get(i);
float[] vertices = polygon.items;
for (int ii = 0, nn = polygon.size; ii < nn; ii += 2) {
float x = vertices[ii];
float y = vertices[ii + 1];
minX = Math.min(minX, x);
minY = Math.min(minY, y);
maxX = Math.max(maxX, x);
maxY = Math.max(maxY, y);
}
}
this.minX = minX;
this.minY = minY;
this.maxX = maxX;
this.maxY = maxY;
}
/** Returns true if the axis aligned bounding box contains the point. */
public boolean aabbContainsPoint (float x, float y) {
return x >= minX && x <= maxX && y >= minY && y <= maxY;
}
/** Returns true if the axis aligned bounding box intersects the line segment. */
public boolean aabbIntersectsSegment (float x1, float y1, float x2, float y2) {
float minX = this.minX;
float minY = this.minY;
float maxX = this.maxX;
float maxY = this.maxY;
if ((x1 <= minX && x2 <= minX) || (y1 <= minY && y2 <= minY) || (x1 >= maxX && x2 >= maxX) || (y1 >= maxY && y2 >= maxY))
return false;
float m = (y2 - y1) / (x2 - x1);
float y = m * (minX - x1) + y1;
if (y > minY && y < maxY) return true;
y = m * (maxX - x1) + y1;
if (y > minY && y < maxY) return true;
float x = (minY - y1) / m + x1;
if (x > minX && x < maxX) return true;
x = (maxY - y1) / m + x1;
if (x > minX && x < maxX) return true;
return false;
}
/** Returns true if the axis aligned bounding box intersects the axis aligned bounding box of the specified bounds. */
public boolean aabbIntersectsSkeleton (SkeletonBounds bounds) {
return minX < bounds.maxX && maxX > bounds.minX && minY < bounds.maxY && maxY > bounds.minY;
}
/** Returns the first bounding box attachment that contains the point, or null. When doing many checks, it is usually more
* efficient to only call this method if {@link #aabbContainsPoint(float, float)} returns true. */
public BoundingBoxAttachment containsPoint (float x, float y) {
Array<FloatArray> polygons = this.polygons;
for (int i = 0, n = polygons.size; i < n; i++)
if (containsPoint(polygons.get(i), x, y)) return boundingBoxes.get(i);
return null;
}
/** Returns true if the polygon contains the point. */
public boolean containsPoint (FloatArray polygon, float x, float y) {
float[] vertices = polygon.items;
int nn = polygon.size;
int prevIndex = nn - 2;
boolean inside = false;
for (int ii = 0; ii < nn; ii += 2) {
float vertexY = vertices[ii + 1];
float prevY = vertices[prevIndex + 1];
if ((vertexY < y && prevY >= y) || (prevY < y && vertexY >= y)) {
float vertexX = vertices[ii];
if (vertexX + (y - vertexY) / (prevY - vertexY) * (vertices[prevIndex] - vertexX) < x) inside = !inside;
}
prevIndex = ii;
}
return inside;
}
/** Returns the first bounding box attachment that contains any part of the line segment, or null. When doing many checks, it
* is usually more efficient to only call this method if {@link #aabbIntersectsSegment(float, float, float, float)} returns
* true. */
public BoundingBoxAttachment intersectsSegment (float x1, float y1, float x2, float y2) {
Array<FloatArray> polygons = this.polygons;
for (int i = 0, n = polygons.size; i < n; i++)
if (intersectsSegment(polygons.get(i), x1, y1, x2, y2)) return boundingBoxes.get(i);
return null;
}
/** Returns true if the polygon contains any part of the line segment. */
public boolean intersectsSegment (FloatArray polygon, float x1, float y1, float x2, float y2) {
float[] vertices = polygon.items;
int nn = polygon.size;
float width12 = x1 - x2, height12 = y1 - y2;
float det1 = x1 * y2 - y1 * x2;
float x3 = vertices[nn - 2], y3 = vertices[nn - 1];
for (int ii = 0; ii < nn; ii += 2) {
float x4 = vertices[ii], y4 = vertices[ii + 1];
float det2 = x3 * y4 - y3 * x4;
float width34 = x3 - x4, height34 = y3 - y4;
float det3 = width12 * height34 - height12 * width34;
float x = (det1 * width34 - width12 * det2) / det3;
if (((x >= x3 && x <= x4) || (x >= x4 && x <= x3)) && ((x >= x1 && x <= x2) || (x >= x2 && x <= x1))) {
float y = (det1 * height34 - height12 * det2) / det3;
if (((y >= y3 && y <= y4) || (y >= y4 && y <= y3)) && ((y >= y1 && y <= y2) || (y >= y2 && y <= y1))) return true;
}
x3 = x4;
y3 = y4;
}
return false;
}
/** The left edge of the axis aligned bounding box. */
public float getMinX () {
return minX;
}
/** The bottom edge of the axis aligned bounding box. */
public float getMinY () {
return minY;
}
/** The right edge of the axis aligned bounding box. */
public float getMaxX () {
return maxX;
}
/** The top edge of the axis aligned bounding box. */
public float getMaxY () {
return maxY;
}
/** The width of the axis aligned bounding box. */
public float getWidth () {
return maxX - minX;
}
/** The height of the axis aligned bounding box. */
public float getHeight () {
return maxY - minY;
}
/** The visible bounding boxes. */
public Array<BoundingBoxAttachment> getBoundingBoxes () {
return boundingBoxes;
}
/** The world vertices for the bounding box polygons. */
public Array<FloatArray> getPolygons () {
return polygons;
}
/** Returns the polygon for the specified bounding box, or null. */
public FloatArray getPolygon (BoundingBoxAttachment boundingBox) {
if (boundingBox == null) throw new IllegalArgumentException("boundingBox cannot be null.");
int index = boundingBoxes.indexOf(boundingBox, true);
return index == -1 ? null : polygons.get(index);
}
}