Added VerticalSeparator() entry point in imgui_internal. Seperator() in an horizontal layout context still does that.

Separator(): Tweak Logging so that the separator text is aligned according to tree padding.

Fixed IsItemHovered() - part of the processing has to be done in ItemAdd() because the widget may alter clipping rectangle temporarily.

Refactor to move the responsability of SetHovered() to ItemHoverable() - previously IsHovered(). Simpler and the parallel to ItemAdd is clearer with the new name.

Removed another msileading difference between the hovered functions (IsWindowContentHoverable() uses the root window already). Sorry for the commit spam! (making small commit to easily be able to Bisect those in case I make a mistake)

IsItemHovered(), IsHovered(): Shallow tweaks, eventually removed all the braces.

Internals: Moved IsWindowContentHoverable() in the file

IsItemHovered(), IsHovered(): Shallow tweaks to make them more symetrical. Removed one set of braces.

Internals: ButtonBehavior(), IsHovered() moved the responsability of flatten_child higher level to ButtonBehavior() - not super sure about the elegance of this

IsItemHovered(), ItemAdd(): finishing cleaning up, moved the code to IsItemHovered() so ItemAdd() is more lightweight and the two IsXXXHovered functions are now very similar, making their differences less confusing.

ItemAdd(): more re-ordering of tests to match IsHovered() + comments

IsItemHovered(), ItemAdd(): Fixed seemingly unnecessary comparaison of root windows, makes IsItemHovered() more consistent with internal IsHovered(). ...

Original test was added in 6e99688 should not have been using RootWindow in the first place.
The difference between public-facing and internal versions would only be noticeable with overlapped child windows, which doesn't really happen anyway

ItemAdd(): re-ordering the tests, submission should now be faster.

ItemAdd(), not performing computation for IsItemRectHovered() which does them itself, allowing us in the next commit to optimize ItemAdd() and make its logic more consistent with IsHovered().

Moved implementation of Hovered-related functions next to each others + comments, before I attempt to work on them. No functional change here.

Fixed not being able to move a window by clicking on one of its child window (#1337, #635), broken by https://github.com/ocornut/imgui/commit/313d388bba42e0634a02b976dcdbae238d25eddc

Removed extraneous ImGui:: prefixes. Declared ColorEditOptionsPopup in imgui_internals.h. Tweaked internal signatures.

Combo: Cleaned up, removed unnecessary code (looks like this part went untouched for a long time!).

ImFont: Renamed (supposedly internal) fields (e.g. XAdvance to AdvanceX). Custom text renderers might be affected if they didn't use the GetCharAdvance() helper function.

ImFont: Renamed ImFont::Glyph to ImFontGlyph (for consistency and so ImFontAtlas types can use it without ordering half of the file). Left a redirection type.

Separator(): output vertical separator when used in horizontal layout mode, so it works in menu bars.

Horizontal layout does the minimum job to be usable internally - not exposed (#97)

Comments, debug code (commented), todo list

WantCaptureMouse: Tweaked logic so WantCaptureMouse can stay false when e.g. hovering over void while an InputText() is active. (#621)

Exposed PushMultiItemsWidths() to imgui_internal.h

Merge pull request #1113 from Urmeli0815/ImGuiSelectableFlags_MenuItem ...

MenuItem: only activate on Release, not on Click (nb: and not on ClickRelease to allow opening menu and selecting something with a single click. Windows seems to behave the same, allowing to click and hold to e.g. Open then move cursor, release on Save and save gets activated)

Begin: Fixed auto-fit calculation code that predict the presence of ascrollbar so it works in the case size constraints are used. I actually don't need this fix now, but earlier experiment with BeginCombo() required this fix.

Begin: Moving some code into a CalcSizeAutoFit() function.

BeginCombo(): rework internals a little to make it easier to provide custom combo-like elements relying in BeginCombo(). ...

BeginPopupEx() doesn't enforce AlwaysAutoResize flag anymore.

SetNextWindowPos: added a ImVec2 pivot parameter for positioning a given a center, bottom-right position, etc. As a generalization of SetNextWindowPosCenter() which is now obsolete. This will be useful for combo-like popups as well. ...

Demo: Simple-overlay window uses the SetWindowPos pivot to select a corner to position itself at.