diff options
Diffstat (limited to 'src/jogl/classes/com/jogamp/graph/math')
| -rwxr-xr-x | src/jogl/classes/com/jogamp/graph/math/VectorUtil.java | 134 |
1 files changed, 104 insertions, 30 deletions
diff --git a/src/jogl/classes/com/jogamp/graph/math/VectorUtil.java b/src/jogl/classes/com/jogamp/graph/math/VectorUtil.java index 2b4a7fd9d..b1f2023f3 100755 --- a/src/jogl/classes/com/jogamp/graph/math/VectorUtil.java +++ b/src/jogl/classes/com/jogamp/graph/math/VectorUtil.java @@ -44,7 +44,7 @@ public class VectorUtil { this.dir = dir;
}
}
-
+
public static final int COLLINEAR = 0;
/** compute the dot product of two points
@@ -88,7 +88,7 @@ public class VectorUtil { newVector[2] = vector[2]*scale;
return newVector;
}
-
+
/** Adds to vectors
* @param v1 vector 1
* @param v2 vector 2
@@ -135,7 +135,7 @@ public class VectorUtil { return out;
}
-
+
/** Matrix Vector multiplication
* @param rawMatrix column matrix (4x4)
* @param vec vector(x,y,z)
@@ -151,7 +151,7 @@ public class VectorUtil { return out;
}
-
+
/** Calculate the midpoint of two values
* @param p1 first value
* @param p2 second vale
@@ -169,9 +169,9 @@ public class VectorUtil { public static float[] mid(float[] p1, float[] p2)
{
float[] midPoint = new float[3];
- midPoint[0] = (p1[0] + p2[0])/2.0f;
- midPoint[1] = (p1[1] + p2[1])/2.0f;
- midPoint[2] = (p1[2] + p2[2])/2.0f;
+ midPoint[0] = (p1[0] + p2[0])*0.5f;
+ midPoint[1] = (p1[1] + p2[1])*0.5f;
+ midPoint[2] = (p1[2] + p2[2])*0.5f;
return midPoint;
}
@@ -206,8 +206,8 @@ public class VectorUtil { public static boolean checkEquality(float[] v1, float[] v2)
{
if(Float.compare(v1[0], v2[0]) == 0 &&
- Float.compare(v1[1], v2[1]) == 0 &&
- Float.compare(v1[2], v2[2]) == 0 )
+ Float.compare(v1[1], v2[1]) == 0 &&
+ Float.compare(v1[2], v2[2]) == 0 )
return true;
return false;
}
@@ -220,7 +220,7 @@ public class VectorUtil { public static boolean checkEqualityVec2(float[] v1, float[] v2)
{
if(Float.compare(v1[0], v2[0]) == 0 &&
- Float.compare(v1[1], v2[1]) == 0)
+ Float.compare(v1[1], v2[1]) == 0)
return true;
return false;
}
@@ -287,7 +287,7 @@ public class VectorUtil { public static float triArea(Vertex a, Vertex b, Vertex c){
return (b.getX() - a.getX()) * (c.getY() - a.getY()) - (b.getY() - a.getY())*(c.getX() - a.getX());
}
-
+
/** Check if a vertex is in triangle using
* barycentric coordinates computation.
* @param a first triangle vertex
@@ -297,25 +297,25 @@ public class VectorUtil { * @return true if p is in triangle (a, b, c), false otherwise.
*/
public static boolean vertexInTriangle(float[] a, float[] b, float[] c, float[] p){
- // Compute vectors
- float[] ac = computeVector(a, c); //v0
- float[] ab = computeVector(a, b); //v1
- float[] ap = computeVector(a, p); //v2
-
- // Compute dot products
- float dot00 = dot(ac, ac);
- float dot01 = dot(ac, ab);
- float dot02 = dot(ac, ap);
- float dot11 = dot(ab, ab);
- float dot12 = dot(ab, ap);
-
- // Compute barycentric coordinates
- float invDenom = 1 / (dot00 * dot11 - dot01 * dot01);
- float u = (dot11 * dot02 - dot01 * dot12) * invDenom;
- float v = (dot00 * dot12 - dot01 * dot02) * invDenom;
-
- // Check if point is in triangle
- return (u > 0) && (v > 0) && (u + v < 1);
+ // Compute vectors
+ float[] ac = computeVector(a, c); //v0
+ float[] ab = computeVector(a, b); //v1
+ float[] ap = computeVector(a, p); //v2
+
+ // Compute dot products
+ float dot00 = dot(ac, ac);
+ float dot01 = dot(ac, ab);
+ float dot02 = dot(ac, ap);
+ float dot11 = dot(ab, ab);
+ float dot12 = dot(ab, ap);
+
+ // Compute barycentric coordinates
+ float invDenom = 1 / (dot00 * dot11 - dot01 * dot01);
+ float u = (dot11 * dot02 - dot01 * dot12) * invDenom;
+ float v = (dot00 * dot12 - dot01 * dot02) * invDenom;
+
+ // Check if point is in triangle
+ return (u >= 0) && (v >= 0) && (u + v < 1);
}
/** Check if points are in ccw order
@@ -353,7 +353,81 @@ public class VectorUtil { }
return area;
}
+
+ /** Compute the general winding of the vertices
+ * @param vertices array of Vertices
+ * @return CCW or CW {@link Winding}
+ */
public static Winding getWinding(ArrayList<Vertex> vertices) {
return area(vertices) >= 0 ? Winding.CCW : Winding.CW ;
}
+
+
+ /** Compute intersection between two segments
+ * @param a vertex 1 of first segment
+ * @param b vertex 2 of first segment
+ * @param c vertex 1 of second segment
+ * @param d vertex 2 of second segment
+ * @return the intersection coordinates if the segments intersect, otherwise
+ * returns null
+ */
+ public static float[] seg2SegIntersection(Vertex a, Vertex b, Vertex c, Vertex d) {
+ float determinant = (a.getX()-b.getX())*(c.getY()-d.getY()) - (a.getY()-b.getY())*(c.getX()-d.getX());
+
+ if (determinant == 0)
+ return null;
+
+ float alpha = (a.getX()*b.getY()-a.getY()*b.getX());
+ float beta = (c.getX()*d.getY()-c.getY()*d.getY());
+ float xi = ((c.getX()-d.getX())*alpha-(a.getX()-b.getX())*beta)/determinant;
+ float yi = ((c.getY()-d.getY())*alpha-(a.getY()-b.getY())*beta)/determinant;
+
+ float gamma = (xi - a.getX())/(b.getX() - a.getX());
+ float gamma1 = (xi - c.getX())/(d.getX() - c.getX());
+ if(gamma <= 0 || gamma >= 1) return null;
+ if(gamma1 <= 0 || gamma1 >= 1) return null;
+
+ return new float[]{xi,yi,0};
+ }
+
+ /** Compute intersection between two lines
+ * @param a vertex 1 of first line
+ * @param b vertex 2 of first line
+ * @param c vertex 1 of second line
+ * @param d vertex 2 of second line
+ * @return the intersection coordinates if the lines intersect, otherwise
+ * returns null
+ */
+ public static float[] line2lineIntersection(Vertex a, Vertex b, Vertex c, Vertex d) {
+ float determinant = (a.getX()-b.getX())*(c.getY()-d.getY()) - (a.getY()-b.getY())*(c.getX()-d.getX());
+
+ if (determinant == 0)
+ return null;
+
+ float alpha = (a.getX()*b.getY()-a.getY()*b.getX());
+ float beta = (c.getX()*d.getY()-c.getY()*d.getY());
+ float xi = ((c.getX()-d.getX())*alpha-(a.getX()-b.getX())*beta)/determinant;
+ float yi = ((c.getY()-d.getY())*alpha-(a.getY()-b.getY())*beta)/determinant;
+
+ return new float[]{xi,yi,0};
+ }
+
+ /** Check if a segment intersects with a triangle
+ * @param a vertex 1 of the triangle
+ * @param b vertex 2 of the triangle
+ * @param c vertex 3 of the triangle
+ * @param d vertex 1 of first segment
+ * @param e vertex 2 of first segment
+ * @return true if the segment intersects at least one segment of the triangle, false otherwise
+ */
+ public static boolean tri2SegIntersection(Vertex a, Vertex b, Vertex c, Vertex d, Vertex e){
+ if(seg2SegIntersection(a, b, d, e) != null)
+ return true;
+ if(seg2SegIntersection(b, c, d, e) != null)
+ return true;
+ if(seg2SegIntersection(a, c, d, e) != null)
+ return true;
+
+ return false;
+ }
}
|