X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=org.simantics.g3d%2Fsrc%2Forg%2Fsimantics%2Fg3d%2Fshape%2FArcCylinder.java;fp=org.simantics.g3d%2Fsrc%2Forg%2Fsimantics%2Fg3d%2Fshape%2FArcCylinder.java;h=ab6178440ab04a8772dd25902eb59cdfcc0d0dd9;hb=58ebeb2baac48f9066c1395a9071f99745574ef9;hp=0000000000000000000000000000000000000000;hpb=498c60eb6adbad0449879bdff55a2e203bfcbb01;p=simantics%2F3d.git

diff --git a/org.simantics.g3d/src/org/simantics/g3d/shape/ArcCylinder.java b/org.simantics.g3d/src/org/simantics/g3d/shape/ArcCylinder.java
new file mode 100644
index 00000000..ab617844
--- /dev/null
+++ b/org.simantics.g3d/src/org/simantics/g3d/shape/ArcCylinder.java
@@ -0,0 +1,152 @@
+package org.simantics.g3d.shape;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.vecmath.AxisAngle4d;
+import javax.vecmath.Point3d;
+import javax.vecmath.Quat4d;
+import javax.vecmath.Tuple3d;
+import javax.vecmath.Vector3d;
+
+import org.simantics.g3d.math.MathTools;
+
+public class ArcCylinder {
+
+	public Mesh create(Point3d s, Point3d v, Point3d e, double rad, int res) {
+		
+		Vector3d v1 = new Vector3d(s);
+		v1.sub(v);
+		
+		Vector3d v2 = new Vector3d(e);
+		v2.sub(v);
+		
+		double a = v2.angle(v1);
+		int steps = 0;
+		double sa = 0.0;
+		
+		Vector3d rn = new Vector3d();
+		Vector3d r1 = null;
+		Vector3d c = null;
+		
+		if ((a +0.0001) > Math.PI) {
+			steps = 1;
+		} else {
+			c = new Vector3d(v2);
+			c.add(v1);
+			c.normalize();
+			c.scale(v1.length() * (1.0/Math.cos(a*0.5)));
+			c.add(v);
+			
+			r1 = new Vector3d(s);
+			r1.sub(c);
+			
+			Vector3d r2 = new Vector3d(e);
+			r2.sub(c);
+			
+			a = r2.angle(r1);
+			
+			rn.cross(v2, v1);
+			rn.normalize();
+			
+			steps = (int)(Math.ceil(a/0.1));
+			if (steps == 0)
+				steps = 1;
+			sa = a/steps;
+		}
+
+		
+		List<Tuple3d> vertices = new ArrayList<Tuple3d>(res * (steps+1));
+		List<Tuple3d> normals = new ArrayList<Tuple3d>(res * (steps+1));
+		List<Integer> indices = new ArrayList<Integer>();
+		
+		for (int i = 0; i <= steps; i++) {
+			Vector3d p;
+			Vector3d t;
+			if (i == 0) {
+				p = new Vector3d(s);
+				t = new Vector3d(v1);
+				t.negate();
+				t.normalize();
+			} else if (i == steps) {
+				p = new Vector3d(e);
+				t = new Vector3d(v2);
+				t.normalize();
+			} else {
+				p = new Vector3d();
+				double ca = sa * i;
+				Quat4d q = MathTools.getQuat(new AxisAngle4d(rn, ca));
+				MathTools.rotate(q, r1, p);
+				t = new Vector3d();
+				t.cross(rn,p);
+				t.normalize();
+				p.add(c);
+				
+			}
+			createCircle(vertices, normals, p, t, rn, res, rad);
+		}
+		int count = steps*res*6;
+		for (int i = 0; i < count; i++) {
+			indices.add(-1);
+		}	
+		createIndices(steps, res, indices);
+		return new Mesh(vertices, normals, indices);
+	}
+	
+	private static void createCircle(List<Tuple3d> points, List<Tuple3d> normals, Tuple3d p, Vector3d t, Vector3d n, int res, double radius) {
+		n = new Vector3d(n);
+		n.scale(radius);
+		
+		for (int index = 0; index < res; index ++) {
+			Vector3d v;
+			if (index == 0) {
+				v = new Vector3d(n);
+				
+			} else {
+				AxisAngle4d aa = new AxisAngle4d(t, (Math.PI * 2 * (double)index)/(double)res);
+				v = new Vector3d();
+				MathTools.rotate(MathTools.getQuat(aa), n, v);
+			}
+			//int vIndex = (i*resolution + index)*3;
+			Vector3d pt = new Vector3d(p);
+			pt.add(v);
+			//points.set(vIndex, pt);
+			points.add(pt);
+			v.normalize();
+			//normals.set(vIndex, v);
+			normals.add(v);
+		}
+	}
+	private static void createIndices(int steps, int resolution, List<Integer> index) {
+		for (int c = 0; c < steps; c++) {
+			for (int s = 0; s < resolution; s++) {
+				int ii = (c * resolution + s) * 6;
+				int iv = c*resolution + s;
+				
+				/*
+			     iv+1 ---- iv + resolution + 1
+				      | /|
+				      |/ |
+				   iv ---- iv + resolution 
+				*/
+				if (s < resolution - 1) {
+					index.set(ii+2,iv);
+					index.set(ii+1,iv+resolution);
+					index.set(ii+0,iv+resolution+1);
+					
+					index.set(ii+5,iv);
+					index.set(ii+4,iv+resolution+1);
+					index.set(ii+3,iv+1);
+				} else {
+					index.set(ii+2,iv);
+					index.set(ii+1,iv+resolution);
+					index.set(ii+0,iv+1);
+					
+					index.set(ii+5,iv);
+					index.set(ii+4,iv+1);
+					index.set(ii+3,iv+1-resolution);
+				}
+			}
+		}
+	}
+}