Pcbnew: Position Relative feature offsets footprint placement

[Sujith]

Issue:
1- when placing the footprints using the 'Position Relative' feature vertically- I have entered the Move
   vector Y value and placed the footprint, but it got placed with a X offset too.Placing horizontally no
   issues.

2- now after rotating the footprint-placing vertically no issues, but the horizontal placement offsets.

so, it seems there is an offsetting issue in one of the axis that depends on the footprint position.

Version:

Application: kicad
Version: (2017-10-31 revision 05ab44f46)-makepkg, release build
Libraries:
    wxWidgets 3.0.3
    libcurl/7.54.1 OpenSSL/1.0.2l zlib/1.2.11 libssh2/1.8.0 nghttp2/1.23.1 librtmp/2.3
Platform: Windows 7 (build 7601, Service Pack 1), 64-bit edition, 64 bit, Little endian, wxMSW
Build Info:
    wxWidgets: 3.0.3 (wchar_t,wx containers,compatible with 2.8)
    Boost: 1.60.0
    Curl: 7.54.1
    Compiler: GCC 7.1.0 with C++ ABI 1011

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_SPICE=ON

[Nick Østergaard (nickoe)]

This feature was from this email thread, [Kicad-developers] [Feature] Position Relative to
https://lists.launchpad.net/kicad-developers/msg29292.html

[Russell Oliver (roliver8143)]

Hi Nick,

I think this might be due to the way the position of the item(s) to be moved is calculated.
It takes the position from the centre of the selection
(https://github.com/KiCad/kicad-source-mirror/blob/9bd55224199850975dd541950be4fdf6e9c371d9/pcbnew/tools/position_relative_tool.cpp#L140)

for a single item this seems to be taking into account the position of the reference and value texts, leading to an incorrect move vector.

[Jeff Young (jeyjey)]

@JP, do your changes to the wording clear this up, or is this a real bug?

[jean-pierre charras (jp-charras)]

@Jeff
I only modified the wording and added a tool tip.

I find this dialog really not easy to use, because the way the transform works is unclear (for me).

My felling is this dialog is seriously missing a help button that displays the info about this way (the way the position of the item(s) to be moved is calculated, what is the rotation center, what is exactly the anchor position ...)

[Jeff Young (jeyjey)]

Future changes/improvements being tracked here: https://bugs.launchpad.net/kicad/+bug/1771424