gEDA-bug: [ geda-Bugs-1928544 ] magnetic net not always snaps to the pin/net

["SourceForge.net" <noreply@xxxxxxxxxxxxxxx>]

Bugs item #1928544, was opened at 2008-03-29 08:41
Message generated for change (Tracker Item Submitted) made by Item Submitter
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=818426&aid=1928544&group_id=161080

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: gschem
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Werner Hoch (werner2101)
Assigned to: Werner Hoch (werner2101)
Summary: magnetic net not always snaps to the pin/net

Initial Comment:
gEDA version: git repo after SHA1: ffd2298ca90e9e8616a2804c5708cb3d2ccb0a83

There are some cases when magnetic net does not connect to the correct position of the pin whichend or net.

To reproduce (1):
* Zoom out to zoom full
* draw some components
* connect them with magnetic net mode
--> zoom in and check the result
(schematic attached for this case)

To reproduce (2):
* turn off the snap to grid
* connect some components (even zoomed in)
* check the connection result

Both cases are not usual use cases for the magnetic net mode, but it uncovers an internal bug:

The coordinates of the magnetic net marker and the other coordinates of the rubbernet (start_x, stop_x, second_x) are stored in screen coordinates. In magnetic mode the coordinates are converted twice. To the screen and back the world. Both conversions can cause rounding errors.

In general, if the a screen pixel is smaller than the half (?) of the current grid, this rounding error may occur.


Possible fix:
Store all variables in world coordinates, only convert them inside the drawing functions to the screen coordinates.

Regards
Werner

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=818426&aid=1928544&group_id=161080


_______________________________________________
geda-bug mailing list
geda-bug@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-bug