mixins: add method for grabbing game object polys.

runelite-mixins/src/main/java/net/runelite/mixins/RSGameObjectMixin.java

@@ -24,15 +24,20 @@
  */
 package net.runelite.mixins;
 
+import java.awt.Polygon;
+import java.awt.geom.Area;
+import java.util.ArrayList;
+import java.util.List;
+import net.runelite.api.Model;
 import net.runelite.api.Perspective;
 import net.runelite.api.Point;
 import net.runelite.api.coords.Angle;
 import net.runelite.api.coords.LocalPoint;
-import java.awt.Polygon;
-import java.awt.geom.Area;
 import net.runelite.api.mixins.Inject;
 import net.runelite.api.mixins.Mixin;
 import net.runelite.api.mixins.Shadow;
+import net.runelite.api.model.Triangle;
+import net.runelite.api.model.Vertex;
 import net.runelite.rs.api.RSClient;
 import net.runelite.rs.api.RSEntity;
 import net.runelite.rs.api.RSGameObject;
@@ -85,6 +90,89 @@ public abstract class RSGameObjectMixin implements RSGameObject
 		return Perspective.getClickbox(client, getModel(), getRsOrientation(), getLocalLocation());
 	}
 
+	@Inject
+	@Override
+	public Polygon[] getPolygons()
+	{
+		Model model = getModel();
+
+		if (model == null)
+		{
+			return null;
+		}
+
+		int localX = getX();
+		int localY = getY();
+
+		int orientation = getRsOrientation();
+
+		final int tileHeight = Perspective.getTileHeight(client, new LocalPoint(localX, localY), client.getPlane());
+
+		List<Triangle> triangles = model.getTriangles();
+
+		triangles = rotate(triangles, orientation);
+
+		List<Polygon> polys = new ArrayList<Polygon>();
+		for (Triangle triangle : triangles)
+		{
+			Vertex vx = triangle.getA();
+			Vertex vy = triangle.getB();
+			Vertex vz = triangle.getC();
+
+			Point x = Perspective.localToCanvas(client,
+				localX - vx.getX(),
+				localY - vx.getZ(),
+				tileHeight + vx.getY());
+
+			Point y = Perspective.localToCanvas(client,
+				localX - vy.getX(),
+				localY - vy.getZ(),
+				tileHeight + vy.getY());
+
+			Point z = Perspective.localToCanvas(client,
+				localX - vz.getX(),
+				localY - vz.getZ(),
+				tileHeight + vz.getY());
+
+			if (x == null || y == null || z == null)
+			{
+				return null;
+			}
+
+			int[] xx =
+				{
+					x.getX(), y.getX(), z.getX()
+				};
+			int[] yy =
+				{
+					x.getY(), y.getY(), z.getY()
+				};
+			polys.add(new Polygon(xx, yy, 3));
+		}
+
+		return polys.toArray(new Polygon[0]);
+	}
+
+	@Inject
+	private List<Triangle> rotate(List<Triangle> triangles, int orientation)
+	{
+		List<Triangle> rotatedTriangles = new ArrayList<Triangle>();
+		for (Triangle triangle : triangles)
+		{
+			Vertex a = triangle.getA();
+			Vertex b = triangle.getB();
+			Vertex c = triangle.getC();
+
+			Triangle rotatedTriangle = new Triangle(
+				a.rotate(orientation),
+				b.rotate(orientation),
+				c.rotate(orientation)
+			);
+			rotatedTriangles.add(rotatedTriangle);
+		}
+		return rotatedTriangles;
+	}
+
 	@Inject
 	@Override
 	public Polygon getConvexHull()