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https://github.com/EsotericSoftware/spine-runtimes.git
synced 2026-02-06 07:14:55 +08:00
[csharp] Ported ConvexDecomposer
This commit is contained in:
badlogic
parent
63c3a48014
commit
686b2b551d
@ -71,6 +71,7 @@
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<Compile Include="src\BlendMode.cs" />
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<Compile Include="src\Bone.cs" />
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<Compile Include="src\BoneData.cs" />
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<Compile Include="src\ConvexDecomposer.cs" />
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<Compile Include="src\Event.cs" />
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<Compile Include="src\EventData.cs" />
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<Compile Include="src\ExposedList.cs" />
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@ -85,6 +86,7 @@
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<Compile Include="src\Skeleton.cs" />
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<Compile Include="src\SkeletonBinary.cs" />
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<Compile Include="src\SkeletonBounds.cs" />
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<Compile Include="src\SkeletonClipping.cs" />
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<Compile Include="src\SkeletonData.cs" />
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<Compile Include="src\SkeletonJson.cs" />
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<Compile Include="src\Skin.cs" />
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@ -28,241 +28,238 @@
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* POSSIBILITY OF SUCH DAMAGE.
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*****************************************************************************/
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using System;
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namespace Spine {
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internal class ConvexDecomposer {
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// private final Array<FloatArray> convexPolygons = new Array();
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// private final Array<ShortArray> convexPolygonsIndices = new Array();
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private readonly ExposedList<ExposedList<float>> convexPolygons = new ExposedList<ExposedList<float>>();
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private readonly ExposedList<ExposedList<short>> convexPolygonsIndices = new ExposedList<ExposedList<short>>();
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// private final ShortArray indicesArray = new ShortArray();
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// private final BooleanArray isConcaveArray = new BooleanArray();
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// private final ShortArray triangles = new ShortArray();
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private readonly ExposedList<short> indicesArray = new ExposedList<short>();
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private readonly ExposedList<bool> isConcaveArray = new ExposedList<bool>();
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private readonly ExposedList<short> triangles = new ExposedList<short>();
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// private final Pool<FloatArray> polygonPool = new Pool() {
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// protected FloatArray newObject() {
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// return new FloatArray(16);
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// }
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//};
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private readonly Pool<ExposedList<float>> polygonPool = new Pool<ExposedList<float>>();
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private readonly Pool<ExposedList<short>> polygonIndicesPool = new Pool<ExposedList<short>>();
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//private final Pool<ShortArray> polygonIndicesPool = new Pool() {
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// protected ShortArray newObject() {
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// return new ShortArray(16);
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//}
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// };
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public ExposedList<ExposedList<float>> Decompose(float[] input) {
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var vertices = input;
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int vertexCount = input.Length >> 1;
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// public Array<FloatArray> decompose(FloatArray input) {
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// float[] vertices = input.items;
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// int vertexCount = input.size >> 1;
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var indicesArray = this.indicesArray;
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indicesArray.Clear();
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short[] indices = indicesArray.Resize(vertexCount).Items;
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for (short i = 0; i < vertexCount; i++)
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indices[i] = i;
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// ShortArray indicesArray = this.indicesArray;
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// indicesArray.clear();
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// short[] indices = indicesArray.setSize(vertexCount);
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// for (short i = 0; i < vertexCount; i++)
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// indices[i] = i;
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var isConcaveArray = this.isConcaveArray;
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bool[] isConcave = isConcaveArray.Resize(vertexCount).Items;
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for (int i = 0, n = vertexCount; i < n; ++i)
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isConcave[i] = IsConcave(i, vertexCount, vertices, indices);
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// BooleanArray isConcaveArray = this.isConcaveArray;
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// boolean[] isConcave = isConcaveArray.setSize(vertexCount);
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// for (int i = 0, n = vertexCount; i < n; ++i)
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// isConcave[i] = isConcave(i, vertexCount, vertices, indices);
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var triangles = this.triangles;
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triangles.Clear();
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triangles.EnsureCapacity(Math.Max(0, vertexCount - 2) << 2);
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// ShortArray triangles = this.triangles;
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// triangles.clear();
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// triangles.ensureCapacity(Math.max(0, vertexCount - 2) << 2);
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while (vertexCount > 3) {
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// Find ear tip.
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int previous = vertexCount - 1, i = 0, next = 1;
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while (true) {
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outer:
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if (!isConcave[i]) {
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int p1 = indices[previous] << 1, p2 = indices[i] << 1, p3 = indices[next] << 1;
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float p1x = vertices[p1], p1y = vertices[p1 + 1];
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float p2x = vertices[p2], p2y = vertices[p2 + 1];
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float p3x = vertices[p3], p3y = vertices[p3 + 1];
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for (int ii = (next + 1) % vertexCount; ii != previous; ii = (ii + 1) % vertexCount) {
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if (!isConcave[ii]) continue;
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int v = indices[ii] << 1;
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float vx = vertices[v], vy = vertices[v + 1];
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if (PositiveArea(p3x, p3y, p1x, p1y, vx, vy)) {
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if (PositiveArea(p1x, p1y, p2x, p2y, vx, vy)) {
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if (PositiveArea(p2x, p2y, p3x, p3y, vx, vy)) goto outer;
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}
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}
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}
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break;
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}
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// while (vertexCount > 3) {
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// // Find ear tip.
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// int previous = vertexCount - 1, i = 0, next = 1;
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// while (true) {
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// outer:
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// if (!isConcave[i]) {
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// int p1 = indices[previous] << 1, p2 = indices[i] << 1, p3 = indices[next] << 1;
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// float p1x = vertices[p1], p1y = vertices[p1 + 1];
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// float p2x = vertices[p2], p2y = vertices[p2 + 1];
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// float p3x = vertices[p3], p3y = vertices[p3 + 1];
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// for (int ii = (next + 1) % vertexCount; ii != previous; ii = (ii + 1) % vertexCount) {
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// if (!isConcave[ii]) continue;
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// int v = indices[ii] << 1;
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// float vx = vertices[v], vy = vertices[v + 1];
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// if (positiveArea(p3x, p3y, p1x, p1y, vx, vy)) {
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// if (positiveArea(p1x, p1y, p2x, p2y, vx, vy)) {
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// if (positiveArea(p2x, p2y, p3x, p3y, vx, vy)) break outer;
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// }
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// }
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// }
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// break;
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// }
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if (next == 0) {
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do {
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if (!isConcave[i]) break;
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i--;
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} while (i > 0);
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break;
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}
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// if (next == 0) {
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// do {
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// if (!isConcave[i]) break;
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// i--;
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// } while (i > 0);
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// break;
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// }
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previous = i;
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i = next;
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next = (next + 1) % vertexCount;
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}
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// previous = i;
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// i = next;
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// next = (next + 1) % vertexCount;
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// }
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// Cut ear tip.
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triangles.Add(indices[(vertexCount + i - 1) % vertexCount]);
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triangles.Add(indices[i]);
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triangles.Add(indices[(i + 1) % vertexCount]);
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indicesArray.RemoveAt(i);
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isConcaveArray.RemoveAt(i);
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vertexCount--;
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// // Cut ear tip.
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// triangles.add(indices[(vertexCount + i - 1) % vertexCount]);
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// triangles.add(indices[i]);
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// triangles.add(indices[(i + 1) % vertexCount]);
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// indicesArray.removeIndex(i);
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// isConcaveArray.removeIndex(i);
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// vertexCount--;
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int previousIndex = (vertexCount + i - 1) % vertexCount;
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int nextIndex = i == vertexCount ? 0 : i;
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isConcave[previousIndex] = IsConcave(previousIndex, vertexCount, vertices, indices);
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isConcave[nextIndex] = IsConcave(nextIndex, vertexCount, vertices, indices);
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}
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// int previousIndex = (vertexCount + i - 1) % vertexCount;
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// int nextIndex = i == vertexCount ? 0 : i;
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// isConcave[previousIndex] = isConcave(previousIndex, vertexCount, vertices, indices);
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// isConcave[nextIndex] = isConcave(nextIndex, vertexCount, vertices, indices);
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// }
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if (vertexCount == 3) {
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triangles.Add(indices[2]);
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triangles.Add(indices[0]);
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triangles.Add(indices[1]);
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}
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// if (vertexCount == 3) {
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// triangles.add(indices[2]);
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// triangles.add(indices[0]);
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// triangles.add(indices[1]);
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// }
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var convexPolygons = this.convexPolygons;
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for (int i = 0, n = convexPolygons.Count; i < n; i++) {
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polygonPool.Free(convexPolygons.Items[i]);
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}
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convexPolygons.Clear();
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// Array<FloatArray> convexPolygons = this.convexPolygons;
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// polygonPool.freeAll(convexPolygons);
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// convexPolygons.clear();
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var convexPolygonsIndices = this.convexPolygonsIndices;
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for (int i = 0, n = convexPolygonsIndices.Count; i < n; i++) {
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polygonIndicesPool.Free(convexPolygonsIndices.Items[i]);
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}
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convexPolygonsIndices.Clear();
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// Array<ShortArray> convexPolygonsIndices = this.convexPolygonsIndices;
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// polygonIndicesPool.freeAll(convexPolygonsIndices);
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// convexPolygonsIndices.clear();
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var polygonIndices = polygonIndicesPool.Obtain();
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polygonIndices.Clear();
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// ShortArray polygonIndices = polygonIndicesPool.obtain();
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// polygonIndices.clear();
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var polygon = polygonPool.Obtain();
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polygon.Clear();
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// FloatArray polygon = polygonPool.obtain();
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// polygon.clear();
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// Merge subsequent triangles if they form a triangle fan.
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int fanBaseIndex = -1, lastWinding = 0;
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short[] trianglesItems = triangles.Items;
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for (int i = 0, n = triangles.Count; i < n; i += 3) {
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int t1 = trianglesItems[i] << 1, t2 = trianglesItems[i + 1] << 1, t3 = trianglesItems[i + 2] << 1;
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float x1 = vertices[t1], y1 = vertices[t1 + 1];
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float x2 = vertices[t2], y2 = vertices[t2 + 1];
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float x3 = vertices[t3], y3 = vertices[t3 + 1];
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// // Merge subsequent triangles if they form a triangle fan.
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// int fanBaseIndex = -1, lastWinding = 0;
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// short[] trianglesItems = triangles.items;
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// for (int i = 0, n = triangles.size; i < n; i += 3) {
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// int t1 = trianglesItems[i] << 1, t2 = trianglesItems[i + 1] << 1, t3 = trianglesItems[i + 2] << 1;
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// float x1 = vertices[t1], y1 = vertices[t1 + 1];
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// float x2 = vertices[t2], y2 = vertices[t2 + 1];
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// float x3 = vertices[t3], y3 = vertices[t3 + 1];
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// If the base of the last triangle is the same as this triangle, check if they form a convex polygon (triangle fan).
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var merged = false;
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if (fanBaseIndex == t1) {
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int o = polygon.Count - 4;
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float[] p = polygon.Items;
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int winding1 = Winding(p[o], p[o + 1], p[o + 2], p[o + 3], x3, y3);
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int winding2 = Winding(x3, y3, p[0], p[1], p[2], p[3]);
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if (winding1 == lastWinding && winding2 == lastWinding) {
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polygon.Add(x3);
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polygon.Add(y3);
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polygonIndices.Add((short)t3);
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merged = true;
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}
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}
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// // If the base of the last triangle is the same as this triangle, check if they form a convex polygon (triangle fan).
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// boolean merged = false;
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// if (fanBaseIndex == t1) {
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// int o = polygon.size - 4;
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// float[] p = polygon.items;
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// int winding1 = winding(p[o], p[o + 1], p[o + 2], p[o + 3], x3, y3);
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// int winding2 = winding(x3, y3, p[0], p[1], p[2], p[3]);
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// if (winding1 == lastWinding && winding2 == lastWinding) {
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// polygon.add(x3);
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// polygon.add(y3);
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// polygonIndices.add(t3);
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// merged = true;
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// }
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// }
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// Otherwise make this triangle the new base.
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if (!merged) {
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if (polygon.Count > 0) {
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convexPolygons.Add(polygon);
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convexPolygonsIndices.Add(polygonIndices);
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}
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polygon = polygonPool.Obtain();
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polygon.Clear();
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polygon.Add(x1);
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polygon.Add(y1);
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polygon.Add(x2);
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polygon.Add(y2);
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polygon.Add(x3);
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polygon.Add(y3);
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polygonIndices = polygonIndicesPool.Obtain();
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polygonIndices.Clear();
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polygonIndices.Add((short)t1);
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polygonIndices.Add((short)t2);
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polygonIndices.Add((short)t3);
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lastWinding = Winding(x1, y1, x2, y2, x3, y3);
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fanBaseIndex = t1;
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}
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}
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// // Otherwise make this triangle the new base.
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// if (!merged) {
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// if (polygon.size > 0) {
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// convexPolygons.add(polygon);
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// convexPolygonsIndices.add(polygonIndices);
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// }
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// polygon = polygonPool.obtain();
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// polygon.clear();
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// polygon.add(x1);
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// polygon.add(y1);
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// polygon.add(x2);
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// polygon.add(y2);
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// polygon.add(x3);
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// polygon.add(y3);
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// polygonIndices = polygonIndicesPool.obtain();
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// polygonIndices.clear();
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// polygonIndices.add(t1);
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// polygonIndices.add(t2);
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// polygonIndices.add(t3);
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// lastWinding = winding(x1, y1, x2, y2, x3, y3);
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// fanBaseIndex = t1;
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// }
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// }
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if (polygon.Count > 0) {
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convexPolygons.Add(polygon);
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convexPolygonsIndices.Add(polygonIndices);
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}
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// if (polygon.size > 0) {
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// convexPolygons.add(polygon);
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// convexPolygonsIndices.add(polygonIndices);
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// }
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// Go through the list of polygons and try to merge the remaining triangles with the found triangle fans.
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for (int i = 0, n = convexPolygons.Count; i < n; i++) {
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polygonIndices = convexPolygonsIndices.Items[i];
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if (polygonIndices.Count == 0) continue;
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int firstIndex = polygonIndices.Items[0];
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int lastIndex = polygonIndices.Items[polygonIndices.Count - 1];
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// // Go through the list of polygons and try to merge the remaining triangles with the found triangle fans.
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// for (int i = 0, n = convexPolygons.size; i < n; i++) {
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// polygonIndices = convexPolygonsIndices.get(i);
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// if (polygonIndices.size == 0) continue;
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// int firstIndex = polygonIndices.get(0);
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// int lastIndex = polygonIndices.get(polygonIndices.size - 1);
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polygon = convexPolygons.Items[i];
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int o = polygon.Count - 4;
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float[] p = polygon.Items;
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float prevPrevX = p[o], prevPrevY = p[o + 1];
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float prevX = p[o + 2], prevY = p[o + 3];
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float firstX = p[0], firstY = p[1];
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float secondX = p[2], secondY = p[3];
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int winding = Winding(prevPrevX, prevPrevY, prevX, prevY, firstX, firstY);
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// polygon = convexPolygons.get(i);
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// int o = polygon.size - 4;
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// float[] p = polygon.items;
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// float prevPrevX = p[o], prevPrevY = p[o + 1];
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// float prevX = p[o + 2], prevY = p[o + 3];
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// float firstX = p[0], firstY = p[1];
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// float secondX = p[2], secondY = p[3];
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// int winding = winding(prevPrevX, prevPrevY, prevX, prevY, firstX, firstY);
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for (int ii = 0; ii < n; ii++) {
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if (ii == i) continue;
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var otherIndices = convexPolygonsIndices.Items[ii];
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if (otherIndices.Count != 3) continue;
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int otherFirstIndex = otherIndices.Items[0];
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int otherSecondIndex = otherIndices.Items[1];
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int otherLastIndex = otherIndices.Items[2];
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// for (int ii = 0; ii < n; ii++) {
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// if (ii == i) continue;
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// ShortArray otherIndices = convexPolygonsIndices.get(ii);
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// if (otherIndices.size != 3) continue;
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// int otherFirstIndex = otherIndices.get(0);
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// int otherSecondIndex = otherIndices.get(1);
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// int otherLastIndex = otherIndices.get(2);
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var otherPoly = convexPolygons.Items[ii];
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float x3 = otherPoly.Items[otherPoly.Count - 2], y3 = otherPoly.Items[otherPoly.Count - 1];
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// FloatArray otherPoly = convexPolygons.get(ii);
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// float x3 = otherPoly.get(otherPoly.size - 2), y3 = otherPoly.get(otherPoly.size - 1);
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if (otherFirstIndex != firstIndex || otherSecondIndex != lastIndex) continue;
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int winding1 = Winding(prevPrevX, prevPrevY, prevX, prevY, x3, y3);
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int winding2 = Winding(x3, y3, firstX, firstY, secondX, secondY);
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if (winding1 == winding && winding2 == winding) {
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otherPoly.Clear();
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otherIndices.Clear();
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polygon.Add(x3);
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polygon.Add(y3);
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polygonIndices.Add((short)otherLastIndex);
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prevPrevX = prevX;
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prevPrevY = prevY;
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prevX = x3;
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prevY = y3;
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ii = 0;
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}
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}
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}
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// if (otherFirstIndex != firstIndex || otherSecondIndex != lastIndex) continue;
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// int winding1 = winding(prevPrevX, prevPrevY, prevX, prevY, x3, y3);
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// int winding2 = winding(x3, y3, firstX, firstY, secondX, secondY);
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// if (winding1 == winding && winding2 == winding) {
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// otherPoly.clear();
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// otherIndices.clear();
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// polygon.add(x3);
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// polygon.add(y3);
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// polygonIndices.add(otherLastIndex);
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// prevPrevX = prevX;
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// prevPrevY = prevY;
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// prevX = x3;
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// prevY = y3;
|
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// ii = 0;
|
||||
// }
|
||||
// }
|
||||
// }
|
||||
// Remove empty polygons that resulted from the merge step above.
|
||||
for (int i = convexPolygons.Count - 1; i >= 0; i--) {
|
||||
polygon = convexPolygons.Items[i];
|
||||
if (polygon.Count == 0) {
|
||||
convexPolygons.RemoveAt(i);
|
||||
polygonPool.Free(polygon);
|
||||
}
|
||||
}
|
||||
|
||||
// // Remove empty polygons that resulted from the merge step above.
|
||||
// for (int i = convexPolygons.size - 1; i >= 0; i--) {
|
||||
// polygon = convexPolygons.get(i);
|
||||
// if (polygon.size == 0) {
|
||||
// convexPolygons.removeIndex(i);
|
||||
// polygonPool.free(polygon);
|
||||
// }
|
||||
// }
|
||||
return convexPolygons;
|
||||
}
|
||||
|
||||
// return convexPolygons;
|
||||
//}
|
||||
static private bool IsConcave(int index, int vertexCount, float[] vertices, short[] indices) {
|
||||
int previous = indices[(vertexCount + index - 1) % vertexCount] << 1;
|
||||
int current = indices[index] << 1;
|
||||
int next = indices[(index + 1) % vertexCount] << 1;
|
||||
return !PositiveArea(vertices[previous], vertices[previous + 1], vertices[current], vertices[current + 1], vertices[next],
|
||||
vertices[next + 1]);
|
||||
}
|
||||
|
||||
//static private boolean isConcave(int index, int vertexCount, float[] vertices, short[] indices) {
|
||||
// int previous = indices[(vertexCount + index - 1) % vertexCount] << 1;
|
||||
// int current = indices[index] << 1;
|
||||
// int next = indices[(index + 1) % vertexCount] << 1;
|
||||
// return !positiveArea(vertices[previous], vertices[previous + 1], vertices[current], vertices[current + 1], vertices[next],
|
||||
// vertices[next + 1]);
|
||||
//}
|
||||
static private bool PositiveArea(float p1x, float p1y, float p2x, float p2y, float p3x, float p3y) {
|
||||
return p1x * (p3y - p2y) + p2x * (p1y - p3y) + p3x * (p2y - p1y) >= 0;
|
||||
}
|
||||
|
||||
//static private boolean positiveArea(float p1x, float p1y, float p2x, float p2y, float p3x, float p3y) {
|
||||
// return p1x * (p3y - p2y) + p2x * (p1y - p3y) + p3x * (p2y - p1y) >= 0;
|
||||
//}
|
||||
|
||||
//static private int winding(float p1x, float p1y, float p2x, float p2y, float p3x, float p3y) {
|
||||
// float px = p2x - p1x, py = p2y - p1y;
|
||||
// return p3x * py - p3y * px + px * p1y - p1x * py >= 0 ? 1 : -1;
|
||||
//}
|
||||
static private int Winding(float p1x, float p1y, float p2x, float p2y, float p3x, float p3y) {
|
||||
float px = p2x - p1x, py = p2y - p1y;
|
||||
return p3x * py - p3y * px + px * p1y - p1x * py >= 0 ? 1 : -1;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user