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Get axes for triangle and AABB.
public static Vector3d[] getAABBAxes( Vector3d[] vertices ) {
Vector3d[] axes = new Vector3d[ 6 ];
// get vertices
Vector3d p0 = vertices[ 0 ];
Vector3d p1 = vertices[ 1 ];
Vector3d p2 = vertices[ 2 ];
Vector3d p3 = vertices[ 3 ];
Vector3d p4 = vertices[ 4 ];
Vector3d p5 = vertices[ 5 ];
Vector3d p6 = vertices[ 6 ];
Vector3d p7 = vertices[ 7 ];
Vector3d edge0 = new Vector3d();
Vector3d edge1 = new Vector3d();
Vector3d edge2 = new Vector3d();
Vector3d edge3 = new Vector3d();
Vector3d edge4 = new Vector3d();
Vector3d edge5 = new Vector3d();
// subtract the two different vertices to get the edge vector
edge0.sub( p1, p0 );
edge1.sub( p2, p0 );
edge2.sub( p4, p0 );
edge3.sub( p7, p5 );
edge4.sub( p7, p3 );
edge5.sub( p7, p6 );
// get perpendicular vector/normal
// cross-product of two edges that are perpendicular to each other
// once for all faces.
Vector3d normal0 = new Vector3d();
Vector3d normal1 = new Vector3d();
Vector3d normal2 = new Vector3d();
Vector3d normal3 = new Vector3d();
Vector3d normal4 = new Vector3d();
Vector3d normal5 = new Vector3d();
normal0.cross( edge0, edge2 );
normal0.normalize();
axes[ 0 ] = normal0;
normal1.cross( edge2, edge1 );
normal1.normalize();
axes[ 1 ] = normal1;
normal2.cross( edge1, edge0 );
normal2.normalize();
axes[ 2 ] = normal2;
normal3.cross( edge4, edge5 );
normal3.normalize();
axes[ 3 ] = normal3;
normal4.cross( edge4, edge3 );
normal4.normalize();
axes[ 4 ] = normal4;
normal5.cross( edge5, edge3 );
normal5.normalize();
axes[ 5 ] = normal5;
return axes;
}
public static Vector3d[] getTriangleAxes( Vector3d[] vertices ) {
Vector3d[] axes = new Vector3d[ 4 ];
// get the current vertex
Vector3d p0 = vertices[ 0 ];
// get the next vertex
Vector3d p1 = vertices[ 1 ];
Vector3d p2 = vertices[ 2 ];
Vector3d edge1 = new Vector3d();
Vector3d edge2 = new Vector3d();
Vector3d edge3 = new Vector3d();
// subtract the two to get the edge vector
edge1.sub( p1, p0 );
edge2.sub( p2, p0 );
edge3.sub( p2, p1 );
// 1 Surface normal
Vector3d normal = new Vector3d();
normal.cross( p0, p1 );
normal.normalize();
axes[ 0 ] = normal;
// 3 Edge normals
Vector3d normal1 = new Vector3d();
normal1.cross( edge1, edge2 );
normal1.normalize();
axes[ 1 ] = normal1;
Vector3d normal2 = new Vector3d();
normal2.cross( edge1, edge3 );
normal2.normalize();
axes[ 2 ] = normal2;
Vector3d normal3 = new Vector3d();
normal3.cross( edge3, edge2 );
normal3.normalize();
axes[ 3 ] = normal3;
return axes;
}
@knownasilya

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@knownasilya

knownasilya Sep 10, 2012

I have replaced the getAABBAxes method with a constant variable:

private static final Vector3d[] AABB_AXES = {
new Vector3d( -1.0, 0.0, 0.0 ),
new Vector3d( 0.0, 0.0, -1.0 ),
new Vector3d( 0.0, -1.0, 0.0 ) };

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knownasilya commented Sep 10, 2012

I have replaced the getAABBAxes method with a constant variable:

private static final Vector3d[] AABB_AXES = {
new Vector3d( -1.0, 0.0, 0.0 ),
new Vector3d( 0.0, 0.0, -1.0 ),
new Vector3d( 0.0, -1.0, 0.0 ) };

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