/******************************************************************************
* 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.
*****************************************************************************/
using System;
namespace Spine {
public class SkeletonClipping {
internal readonly Triangulator triangulator = new Triangulator();
internal readonly ExposedList<float> clippingPolygon = new ExposedList<float>();
internal readonly ExposedList<float> clipOutput = new ExposedList<float>(128);
internal readonly ExposedList<float> clippedVertices = new ExposedList<float>(128);
internal readonly ExposedList<int> clippedTriangles = new ExposedList<int>(128);
internal readonly ExposedList<float> clippedUVs = new ExposedList<float>(128);
internal readonly ExposedList<float> scratch = new ExposedList<float>();
internal ClippingAttachment clipAttachment;
internal ExposedList<ExposedList<float>> clippingPolygons;
public ExposedList<float> ClippedVertices { get { return clippedVertices; } }
public ExposedList<int> ClippedTriangles { get { return clippedTriangles; } }
public ExposedList<float> ClippedUVs { get { return clippedUVs; } }
public bool IsClipping { get { return clipAttachment != null; } }
public int ClipStart (Slot slot, ClippingAttachment clip) {
if (clipAttachment != null) return 0;
clipAttachment = clip;
int n = clip.worldVerticesLength;
float[] vertices = clippingPolygon.Resize(n).Items;
clip.ComputeWorldVertices(slot, 0, n, vertices, 0, 2);
MakeClockwise(clippingPolygon);
clippingPolygons = triangulator.Decompose(clippingPolygon, triangulator.Triangulate(clippingPolygon));
foreach (var polygon in clippingPolygons) {
MakeClockwise(polygon);
polygon.Add(polygon.Items[0]);
polygon.Add(polygon.Items[1]);
}
return clippingPolygons.Count;
}
public void ClipEnd (Slot slot) {
if (clipAttachment != null && clipAttachment.endSlot == slot.data) ClipEnd();
}
public void ClipEnd () {
if (clipAttachment == null) return;
clipAttachment = null;
clippingPolygons = null;
clippedVertices.Clear();
clippedTriangles.Clear();
clippingPolygon.Clear();
}
public void ClipTriangles (float[] vertices, int verticesLength, int[] triangles, int trianglesLength, float[] uvs) {
ExposedList<float> clipOutput = this.clipOutput, clippedVertices = this.clippedVertices;
var clippedTriangles = this.clippedTriangles;
var polygons = clippingPolygons.Items;
int polygonsCount = clippingPolygons.Count;
int index = 0;
clippedVertices.Clear();
clippedUVs.Clear();
clippedTriangles.Clear();
//outer:
for (int i = 0; i < trianglesLength; i += 3) {
int vertexOffset = triangles[i] << 1;
float x1 = vertices[vertexOffset], y1 = vertices[vertexOffset + 1];
float u1 = uvs[vertexOffset], v1 = uvs[vertexOffset + 1];
vertexOffset = triangles[i + 1] << 1;
float x2 = vertices[vertexOffset], y2 = vertices[vertexOffset + 1];
float u2 = uvs[vertexOffset], v2 = uvs[vertexOffset + 1];
vertexOffset = triangles[i + 2] << 1;
float x3 = vertices[vertexOffset], y3 = vertices[vertexOffset + 1];
float u3 = uvs[vertexOffset], v3 = uvs[vertexOffset + 1];
for (int p = 0; p < polygonsCount; p++) {
int s = clippedVertices.Count;
if (Clip(x1, y1, x2, y2, x3, y3, polygons[p], clipOutput)) {
int clipOutputLength = clipOutput.Count;
if (clipOutputLength == 0) continue;
float d0 = y2 - y3, d1 = x3 - x2, d2 = x1 - x3, d4 = y3 - y1;
float d = 1 / (d0 * d2 + d1 * (y1 - y3));
int clipOutputCount = clipOutputLength >> 1;
float[] clipOutputItems = clipOutput.Items;
float[] clippedVerticesItems = clippedVertices.Resize(s + clipOutputCount * 2).Items;
float[] clippedUVsItems = clippedUVs.Resize(s + clipOutputCount * 2).Items;
for (int ii = 0; ii < clipOutputLength; ii += 2) {
float x = clipOutputItems[ii], y = clipOutputItems[ii + 1];
clippedVerticesItems[s] = x;
clippedVerticesItems[s + 1] = y;
float c0 = x - x3, c1 = y - y3;
float a = (d0 * c0 + d1 * c1) * d;
float b = (d4 * c0 + d2 * c1) * d;
float c = 1 - a - b;
clippedUVsItems[s] = u1 * a + u2 * b + u3 * c;
clippedUVsItems[s + 1] = v1 * a + v2 * b + v3 * c;
s += 2;
}
s = clippedTriangles.Count;
int[] clippedTrianglesItems = clippedTriangles.Resize(s + 3 * (clipOutputCount - 2)).Items;
clipOutputCount--;
for (int ii = 1; ii < clipOutputCount; ii++) {
clippedTrianglesItems[s] = index;
clippedTrianglesItems[s + 1] = index + ii;
clippedTrianglesItems[s + 2] = index + ii + 1;
s += 3;
}
index += clipOutputCount + 1;
}
else {
float[] clippedVerticesItems = clippedVertices.Resize(s + 3 * 2).Items;
float[] clippedUVsItems = clippedUVs.Resize(s + 3 * 2).Items;
clippedVerticesItems[s] = x1;
clippedVerticesItems[s + 1] = y1;
clippedVerticesItems[s + 2] = x2;
clippedVerticesItems[s + 3] = y2;
clippedVerticesItems[s + 4] = x3;
clippedVerticesItems[s + 5] = y3;
clippedUVsItems[s] = u1;
clippedUVsItems[s + 1] = v1;
clippedUVsItems[s + 2] = u2;
clippedUVsItems[s + 3] = v2;
clippedUVsItems[s + 4] = u3;
clippedUVsItems[s + 5] = v3;
s = clippedTriangles.Count;
int[] clippedTrianglesItems = clippedTriangles.Resize(s + 3).Items;
clippedTrianglesItems[s] = index;
clippedTrianglesItems[s + 1] = index + 1;
clippedTrianglesItems[s + 2] = index + 2;
index += 3;
break; //continue outer;
}
}
}
}
/** Clips the input triangle against the convex, clockwise clipping area. If the triangle lies entirely within the clipping
* area, false is returned. The clipping area must duplicate the first vertex at the end of the vertices list. */
internal bool Clip (float x1, float y1, float x2, float y2, float x3, float y3, ExposedList<float> clippingArea, ExposedList<float> output) {
var originalOutput = output;
var clipped = false;
// Avoid copy at the end.
ExposedList<float> input = null;
if (clippingArea.Count % 4 >= 2) {
input = output;
output = scratch;
} else {
input = scratch;
}
input.Clear();
input.Add(x1);
input.Add(y1);
input.Add(x2);
input.Add(y2);
input.Add(x3);
input.Add(y3);
input.Add(x1);
input.Add(y1);
output.Clear();
float[] clippingVertices = clippingArea.Items;
int clippingVerticesLast = clippingArea.Count - 4;
for (int i = 0; ; i += 2) {
float edgeX = clippingVertices[i], edgeY = clippingVertices[i + 1];
float edgeX2 = clippingVertices[i + 2], edgeY2 = clippingVertices[i + 3];
float deltaX = edgeX - edgeX2, deltaY = edgeY - edgeY2;
float[] inputVertices = input.Items;
int inputVerticesLength = input.Count - 2, outputStart = output.Count;
for (int ii = 0; ii < inputVerticesLength; ii += 2) {
float inputX = inputVertices[ii], inputY = inputVertices[ii + 1];
float inputX2 = inputVertices[ii + 2], inputY2 = inputVertices[ii + 3];
bool side2 = deltaX * (inputY2 - edgeY2) - deltaY * (inputX2 - edgeX2) > 0;
if (deltaX * (inputY - edgeY2) - deltaY * (inputX - edgeX2) > 0) {
if (side2) { // v1 inside, v2 inside
output.Add(inputX2);
output.Add(inputY2);
continue;
}
// v1 inside, v2 outside
float c0 = inputY2 - inputY, c2 = inputX2 - inputX;
float ua = (c2 * (edgeY - inputY) - c0 * (edgeX - inputX)) / (c0 * (edgeX2 - edgeX) - c2 * (edgeY2 - edgeY));
output.Add(edgeX + (edgeX2 - edgeX) * ua);
output.Add(edgeY + (edgeY2 - edgeY) * ua);
}
else if (side2) { // v1 outside, v2 inside
float c0 = inputY2 - inputY, c2 = inputX2 - inputX;
float ua = (c2 * (edgeY - inputY) - c0 * (edgeX - inputX)) / (c0 * (edgeX2 - edgeX) - c2 * (edgeY2 - edgeY));
output.Add(edgeX + (edgeX2 - edgeX) * ua);
output.Add(edgeY + (edgeY2 - edgeY) * ua);
output.Add(inputX2);
output.Add(inputY2);
}
clipped = true;
}
if (outputStart == output.Count) { // All edges outside.
originalOutput.Clear();
return true;
}
output.Add(output.Items[0]);
output.Add(output.Items[1]);
if (i == clippingVerticesLast) break;
var temp = output;
output = input;
output.Clear();
input = temp;
}
if (originalOutput != output) {
originalOutput.Clear();
for (int i = 0, n = output.Count - 2; i < n; i++) {
originalOutput.Add(output.Items[i]);
}
} else {
originalOutput.Resize(originalOutput.Count - 2);
}
return clipped;
}
static void MakeClockwise (ExposedList<float> polygon) {
float[] vertices = polygon.Items;
int verticeslength = polygon.Count;
float area = vertices[verticeslength - 2] * vertices[1] - vertices[0] * vertices[verticeslength - 1], p1x, p1y, p2x, p2y;
for (int i = 0, n = verticeslength - 3; i < n; i += 2) {
p1x = vertices[i];
p1y = vertices[i + 1];
p2x = vertices[i + 2];
p2y = vertices[i + 3];
area += p1x * p2y - p2x * p1y;
}
if (area < 0) return;
for (int i = 0, lastX = verticeslength - 2, n = verticeslength >> 1; i < n; i += 2) {
float x = vertices[i], y = vertices[i + 1];
int other = lastX - i;
vertices[i] = vertices[other];
vertices[i + 1] = vertices[other + 1];
vertices[other] = x;
vertices[other + 1] = y;
}
}
}
}