Changeset 10915 in josm for trunk/src


Ignore:
Timestamp:
2016-08-29T18:21:41+02:00 (3 years ago)
Author:
michael2402
Message:

Trim interpolate in EastNorth/LatLon for performance and add comment explaining it. Added unit tests.

Location:
trunk/src/org/openstreetmap/josm/data/coor
Files:
2 edited

Legend:

Unmodified
Added
Removed
  • trunk/src/org/openstreetmap/josm/data/coor/EastNorth.java

    r10378 r10915  
    8282     */
    8383    public EastNorth interpolate(EastNorth en2, double proportion) {
    84         return new EastNorth(this.x + proportion * (en2.x - this.x),
    85                 this.y + proportion * (en2.y - this.y));
     84        // this is an alternate form of this.x + proportion * (en2.x - this.x) that is slightly faster
     85        return new EastNorth((1 - proportion) * this.x + proportion * en2.x,
     86                (1 - proportion) * this.y + proportion * en2.y);
    8687    }
    8788
     
    9293     */
    9394    public EastNorth getCenter(EastNorth en2) {
    94         return new EastNorth((this.x + en2.x)/2.0, (this.y + en2.y)/2.0);
     95        // The JIT will inline this for us, it is as fast as the normal /2 approach
     96        return interpolate(en2, .5);
    9597    }
    9698
  • trunk/src/org/openstreetmap/josm/data/coor/LatLon.java

    r10914 r10915  
    427427     */
    428428    public LatLon interpolate(LatLon ll2, double proportion) {
    429         return new LatLon(this.lat() + proportion * (ll2.lat() - this.lat()),
    430                 this.lon() + proportion * (ll2.lon() - this.lon()));
     429        // this is an alternate form of this.lat() + proportion * (ll2.lat() - this.lat()) that is slightly faster
     430        return new LatLon((1 - proportion) * this.lat() + proportion * ll2.lat(),
     431                (1 - proportion) * this.lon() + proportion * ll2.lon());
    431432    }
    432433
     
    437438     */
    438439    public LatLon getCenter(LatLon ll2) {
     440        // The JIT will inline this for us, it is as fast as the normal /2 approach
    439441        return interpolate(ll2, .5);
    440442    }
Note: See TracChangeset for help on using the changeset viewer.