Current displayed data position changes when you press TAB

[IlBano]

What steps will reproduce the problem?

1. load an arbitrary amount of data from OSM
2. press TAB to hide/show the toolbox

What is the expected result?

The current displayed data should remain in the same position as it was before hiding/showing toolbox

What happens instead?

The position of data on screen moves some pixel to the right every time the toolbox is set to hide with TAB key

Please provide any additional information below. Attach a screenshot if possible.

The previous stable release of JOSM was not affected

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2017-05-02 23:28:33 +0200 (Tue, 02 May 2017)
Build-Date:2017-05-02 21:34:40
Revision:12039
Relative:URL: ^/trunk

Identification: JOSM/1.5 (12039 en) Windows 7 32-Bit
Memory Usage: 236 MB / 247 MB (110 MB allocated, but free)
Java version: 1.8.0_101-b13, Oracle Corporation, Java HotSpot(TM) Client VM
Screen: \Display0 1600x900
Maximum Screen Size: 1600x900
VM arguments: [-Djava.security.manager, -Djava.security.policy=file:<java.home>\lib\security\javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>\bin, -Djnlpx.origFilenameArg=%UserProfile%\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\56\1ee8cfb8-2681b3e8, -Djnlpx.remove=false, -Djava.util.Arrays.useLegacyMergeSort=true, -Djnlpx.splashport=58723, -Djnlp.application.href=https://josm.openstreetmap.de/download/josm.jnlp, -Djnlpx.jvm=<java.home>\bin\javaw.exe]
Dataset consistency test: No problems found

Plugins:
+ apache-commons (32994)
+ buildings_tools (33004)
+ ejml (32680)
+ geotools (33042)
+ jts (32699)
+ opendata (33245)
+ utilsplugin2 (33212)

Tagging presets:
+ D:\Dati\Josm\myJosmPresets.xml

Last errors/warnings:
- W:  Culvert: Could not get presets icon presets/tunnel.png
- E: Failed to locate image 'presets/bridge.png'
- W:  Bridge: Could not get presets icon presets/bridge.png
- E: Failed to locate image 'presets/river.png'
- W:  Ditch: Could not get presets icon presets/river.png
- E: Failed to locate image 'presets/parking.png'
- W:  Parking: Could not get presets icon presets/parking.png
- E: Failed to locate image 'presets/way_unclassified.png'
- W:  Service Hwy: Could not get presets icon presets/way_unclassified.png

[bastiK]

Klumbumbus, regression from what version?

[Klumbumbus]

I don't know, I didn't check. I just added the keyword, as IlBano said "The previous stable release of JOSM was not affected"

[bastiK]

Okay, right.

[Klumbumbus]

I made a quick check with versions from https://josm.openstreetmap.de/download/. Should be somewehere between 11839 and 11845

[bastiK]

proposed fix:

src/org/openstreetmap/josm/gui/MapViewState.java

@@ -230 +230 @@
     }
 
     /**
-     * Gets the center of the view, rounded to a pixel coordinate
-     * @return The center position.
-     * @since 10856
-     */
-    public MapViewPoint getCenterAtPixel() {
-        return getForView(viewWidth / 2, viewHeight / 2);
-    }
-
-    /**
      * Gets the width of the view on the Screen;
      * @return The width of the view component in screen pixel.
      */

src/org/openstreetmap/josm/gui/NavigatableComponent.java

@@ -301 +301 @@
      * Zoom in current view. Use configured zoom step and scaling settings.
      */
     public void zoomIn() {
-        zoomTo(state.getCenterAtPixel().getEastNorth(), scaleZoomIn());
+        zoomTo(state.getCenter().getEastNorth(), scaleZoomIn());
     }
 
     /**
@@ -308 +308 @@
      * Zoom out current view. Use configured zoom step and scaling settings.
      */
     public void zoomOut() {
-        zoomTo(state.getCenterAtPixel().getEastNorth(), scaleZoomOut());
+        zoomTo(state.getCenter().getEastNorth(), scaleZoomOut());
     }
 
     protected void updateLocationState() {
@@ -405 +405 @@
      * @return the current center of the viewport
      */
     public EastNorth getCenter() {
-        return state.getCenterAtPixel().getEastNorth();
+        return state.getCenter().getEastNorth();
     }
 
     /**

[Don-vip]

Replying to bastiK:

proposed fix:

looks good, is there a reason not to commit it?

[michael2402]

It should be fine.

This was used to align the view to pixels. Now that we have other code for that it should be OK.

Have you tested zooming in and out a lot? There might be situations where the pixel rounding will introduce a offset so that you move the map by zooming. It did not happen in my current tests, but might be related to map view size/...

[bastiK]

In 12074/josm:

fixed #14740 - Current displayed data position changes when you press TAB

[bastiK]

Replying to Don-vip:

Replying to bastiK:

proposed fix:

looks good, is there a reason not to commit it?

I wasn't sure what getCenterAtPixel was intended for.

[bastiK]

Replying to michael2402:

It should be fine.

This was used to align the view to pixels. Now that we have other code for that it should be OK.

Thanks!

Have you tested zooming in and out a lot? There might be situations where the pixel rounding will introduce a offset so that you move the map by zooming. It did not happen in my current tests, but might be related to map view size/...

Seems to be okay, but this can be very subtle, so we'll see.

[bastiK]

In 12076/josm:

see #14740 - update test

[IlBano]

I just found out that the same problem happens also when you move around using CTRL+<arrow key>... just to gives further details since I'm not able to understand if the proposed patch fixes also this.

[bastiK]

The proposed patch has already been applied, please download version 12074 or later and test yourself!

[anonymous]

Replying to bastiK:

The proposed patch has already been applied, please download version 12074 or later and test yourself!

Works with 12081. Thanks