[Reproducible] with "LibreOffice 3.3.2  – WIN7  Home Premium  (64bit) German UI [OOO330m19 (Build:202 / tag 3.3.2.2)]"

Created attachment 45169 [details]
Demo, see Comment 1

Demo showing inconsistent and wrong flip behavior.

Created attachment 45185 [details]
flip-rotate comparison

Flip-rotate comparison.  Note that the text position is retained (centre justified text) in both examples.  The shape is definitely flipped in the flip one.

Created attachment 93387 [details]
new example of the same phenomenon created in 4.2.0.4

I have added a third attachment showing the problem being still present in 4.2.0.4

Seems inherited from OO. There were changes in text position, but also with 5.0-dev, it's still inconsistent.

*** Bug 50547 has been marked as a duplicate of this bug. ***

From Bug 50547:

Current behavior:
Text that is flipped horizontally or vertically is not correct.  The letters are not mirrored.

Expected behavior:
Flipping text horizontally should cause each letter to be reversed left-to-right, and those reversed letters should be printed right-to-left.  Flipping text vertically should cause each letter to be inverted top-to-bottom, and those inverted letters should be printed left-to-right.  In either case the letters should be mirror-images of ordinary printed letters.

Please note, however, that I disagree with Bug 35913 reporter's position that the text should always be readable (e.g., left-to-right for English).  I think that flipping, which is mirror-imaging, should operate on text the same as it does on shapes.  After all, the person performing the operation may wish to treat the text characters as shapes and flip them.

Created attachment 119101 [details]
Variating demo with recent version V5.0.2

The bug was already present in old StarOffice 5.2 from 2000-05-08. (I tested today.)
Heritage and legacy are powerful.

Nonetheless the bug should finally get fixed.

This bug affects not only the text but also to inserted images / shapes everything.

Also when we select the image and drag the control pointers (small green squares - appear around the image) towards left / right or Up / down .. its expected the image should get flipped horizontally or vertically respectively ... its not Happening as well !

Seriously the most stupid bug, I wonder why such basic functionalities are not taken on highest priorities by developers

The afflicted component of this bug was formerly set to UI. This was a guess. Some investigation shows: The actual bug should be found in the flip routines. The kind of the errors occurring with > 'Flip' > 'Horizontally' may differ:
Example:

A line with asymmetric arrows containing Text and flipped horizontally will
- correctly be mirrored with respect to the line and arrows
- while the text will be rotated by 180° (already reported).

A rectangle containing text and an asymmetric 'Gradient' will not be changed at all by a horizontal flip: undisputable bug with respect to the shape/gradient.

See attachment demonstrating the differences (made with V5.0.2).
The combination of errors cannot easily be ascribed to the UI.

Component changed to 'Draw'.

(Text being part of a graphic object should always take part in flipping/rotating the objects. There is a primordial inconsisteny however, regarding sizes as long as the text actually is text and not graphics.)

Created attachment 120158 [details]
demonstrating differences depending on the type of shape

Created attachment 120249 [details]
Image flip issue examples

Added Image Flip Issue Examples (additional)

Few strange things noted are --

1) Images flipped in libreoffice are not appearing well in libreoffice itself, but if same image is copy pasted in external application like GIMP or PINTA, pasted image appears exactly as per our expectation (flipped appropriately)

2) The issue is ONLY for images inserted from libreoffice gallery or other.png images tested. The other inserted images (.jpg / jpeg etc) flip perfectly well.

Text is not flipped horizontally...

Version: 6.1.0.0.alpha0+
Build ID: fa2dd2ba03f8be1f148dca8f6164daaf7bbf7d96
CPU threads: 4; OS: Linux 4.13; UI render: default; VCL: gtk3; 
Locale: ca-ES (ca_ES.UTF-8); Calc: group

Bug still present. Flip horizontally and vertically should be consistent with text. Flip should not modify text behavior while I can change it by using rotation.

The current behavior is the same as in MS Office and as it has been since years. So I would not change it.

A different problem is, to get a mirroring, which includes mirroring the text. I mean so, as if it is an image.

From point of file format, we would be able, to do these:
(a) Describe the current behavior by using the attributes 'draw:mirror-horizontal' and 'draw:mirror-vertical' of the <draw:enhanced-geometry> element as it is done now. But in addition use the draw:transform attribute of the <draw:custom-shape> element to express mirroring, which includes the text.
(b) Use the 3D features of a custom-shape. Implement it so, that the text is included in the 3D-object, so that it would look mirrored if the object is rotated around the vertical or horizontal axis by 180°. That would in addition give a better compatibility to the 3D-features of MS Office.

(In reply to Regina Henschel from comment #24)
> The current behavior is the same as in MS Office and as it has been since
> years. So I would not change it.
> 
The current behaviour of the >Flipp Horizontally< (do nothing) and >Flipp Vertically< (mirror centrally) is so obviouly absurd that we cannot expect anybody to rely on these effects. 

"Better wrong than incompatible" isn't an option in this case.

If there are inconquerable technical reasons thwarting an actual solution, graphical objects containing text must either refuse completely to flip or ask for an affirmation.  

(Behaviour unchanged in V7.1.1.1)

Sorry, I did not see the challenge in 2022 (I have been unwell).

This behaviour is unchanged in 7.5.2.2