QCAD Bugtracker

Text with é turns into È.

See:
http://www.qcad.org/rsforum/viewtopic.php?f=89&t=2548

SVG import fails if no resolution is specified for SVGImporter.

Texts in CAD fonts with characters for which no glyph is defined report a wrong bounding box which always includes the absolute zero point. This makes the spatial index ineffective for drawings containing many such texts (typically complex drawings from international users).

Insert block with attributes: third attribute input not working

This affects only certain KDE installations:
- Fedora 12 with KDE
- Kubuntu 13.04

Once the print dialog is displayed, it will print even if I “cancel” or “x” the page.

Title says it all. Cannot get QCAD to synchronise attributes on Fedora 19 box with QCAD 3.2.2 installed as the machine hangs (a single core of CPU maxed out). This is not present on my Windows machine (Windwows 7).

I can provide a sample file privately if needed.

Kurt

If the keep proportions button is checked in the scale dialog, no scaling is performed.

Dear Sir:
I am an user in Taiwan. I need to use Chinese. While editing, the font appearance can be display in view port, but after saving-closing-re-opening, the font type is missing. For example, while I type Chinese with font type “B” or “C” and save the file, the font all become font type “A” with reopening and the “Main Font” selector inside “Text” dialog window is blank. I need to re-open “Text” dialogue window and re-select font type, then click the working view port, the display of text changes. Its inconvient. In previous version it’s ok. I can’t remember the exact version of well-saving-Chinese-font function because my computer is not in my house. It might be version 3.1.x. I don’t think it’s a major problem, but could you please deal with this problem while having time.

Inserting a block with attributes into a drawing with a different unit results in wrongly scaled attribute entities.

Workaround:
Sync block attributes after insert.

Inserting part library items with attributes definitions can result in attributes being created with invalid layer IDs (from the source document but invalid in the target document).

If the segment of an ellipse is limited by another ellipse with the same ratio and rotation, the break out tool cannot find the correct intersection to break out to.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=2586&view=unread#unread

When opening or closing QCAD the command line isn’t staying active.

Projecting text into an isometric plane crashes QCAD - unless the text is first exploded, which is not always an acceptable appearance.

XP/32

Info Tools - Area: “Add measurement to drawing” doesn’t work as expected

See:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=2595

The block hierarchy is lost after saving. Only one item appears in the block after reload, and it is doubled outside, too.

attached file:

Tried to put the four patches and the bar in a “Pzeile” block, this works, but after save and open, only the bar is in the block and is doubled to layer “0”.

The attached file is the destroyed version with removed doublette.

This seems to have somehow surfaced once again, this time on FreeBSD (that is, Linux builds are unaffected).

This diff, based on the suggestion from the forum post, seems to fix it:

--- a/src/3rdparty/qt-labs-qtscriptgenerator-4.8.5/qtbindings/qtbindings.pro
+++ b/src/3rdparty/qt-labs-qtscriptgenerator-4.8.5/qtbindings/qtbindings.pro
@@ -13,3 +13,7 @@ SUBDIRS = qtscript_core \
          qtscript_uitools
 
          #qs_eval
+
+freebsd* {
+       SUBDIRS -= qtscript_phonon
+}

Somehow (especially in light of the forum post) it doesn’t seem a very robust solution, though.

QCAD community, Git rev 3ff487, FreeBSD 9.2, Qt 4.8.5.

As came up towards the end of  FS#892 .

What happens is a change in src/3rdparty/dxflib/src/dl_dxf.cpp does trigger a rebuild of release/libdxflib.a, but this does not, in turn, trigger a re-link of plugins/libqcaddxf.so, a (the?) consumer of libdxflib.a.

This causes partial rebuilds to be broken (I think I got puzzled by this earlier too).

How to reproduce: on a fully built tree, `touch src/3rdparty/dxflib/src/dl_dxf.cpp’ then `make’. Nothing but libdxflib.a gets rebuilt.

I suspect it was a79f70, that’s when setCustomProperty() and friends changed.

(slightly reformatted so it doesn’t completely break preformatted display)

g++ -c -m64 -pipe -O2 -Wall -W -D_REENTRANT -DQT_WEBKIT -DQCAD_DLL -DPTHREADS
    -DHAVE_PTHREAD_H -DQT_NO_DEBUG -DQT_WEBKIT_LIB -DQT_SCRIPT_LIB
    -DQT_SCRIPTTOOLS_LIB -DQT_SVG_LIB -DQT_SQL_LIB -DQT_XMLPATTERNS_LIB -DQT_XML_LIB
    -DQT_OPENGL_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED
    -I/usr/share/qt4/mkspecs/linux-g++-64 -I. -I/usr/include/qt4/QtHelp
    -I/usr/include/qt4/QtDesigner -I/usr/include/qt4/QtUiTools
    -I/usr/include/qt4/QtCore -I/usr/include/qt4/QtNetwork -I/usr/include/qt4/QtGui
    -I/usr/include/qt4/QtOpenGL -I/usr/include/qt4/QtXml
    -I/usr/include/qt4/QtXmlPatterns -I/usr/include/qt4/QtSql
    -I/usr/include/qt4/QtSvg -I/usr/include/qt4/QtScriptTools
    -I/usr/include/qt4/QtScript -I/usr/include/qt4/QtWebKit -I/usr/include/qt4
    -I../../../src/core -I../../../src/core/math -I../../../src/grid
    -I../../../src/snap -I../../../src/gui -I../../../src/entity
    -I../../../src/operations -I../../../src/scripting -I../../../src/stemmer
    -I../../../src/scripting/ecmaapi -I../../../src/scripting/ecmaapi/generated
    -I../../../src/scripting/ecmaapi/adapters -I../../../src/io/dxf
    -I../../../src/spatialindex -I../../../src/3rdparty -I/usr/X11R6/include
    -Irelease -o release/MainWindow.o MainWindow.cpp
In file included from MainWindow.cpp:13:0:
../../../src/spatialindex/RSpatialIndexNavel.h: In member function ‘virtual void
    RSpatialIndexNavel::Visitor::visitData(std::vector<const SpatialIndex::IData*>&)’:
../../../src/spatialindex/RSpatialIndexNavel.h:191:77: warning: format ‘%Ld’
    expects argument of type ‘long long int’, but argument 2 has type
    ‘SpatialIndex::id_type {aka long int}’ [-Wformat]
MainWindow.cpp: In constructor ‘MainWindow::MainWindow(QWidget*)’:
MainWindow.cpp:79:54: error: no matching function for call to
    ‘RLineEntity::setCustomProperty(const char [14], int)’
MainWindow.cpp:79:54: note: candidate is:
../../../src/core/RObject.h:165:10: note:
    void RObject::setCustomProperty(const QString&, const QString&, const QVariant&)
../../../src/core/RObject.h:165:10: note:   candidate expects 3 arguments, 2 provided
MainWindow.cpp:80:66: error: no matching function for call to
    ‘RLineEntity::setCustomProperty(const char [17], const char [10])’
MainWindow.cpp:80:66: note: candidate is:
../../../src/core/RObject.h:165:10: note:
    void RObject::setCustomProperty(const QString&, const QString&, const QVariant&)
../../../src/core/RObject.h:165:10: note:   candidate expects 3 arguments, 2 provided
make[4]: *** [release/MainWindow.o] Error 1

Linux, Qt 4.8.1, GCC 4.6.4

6a5c66 on both FreeBSD and Linux (particular example on FreeBSD). The following diff is present, but it should be a no-op in this regard:

--- a/shared.pri
+++ b/shared.pri
@@ -11,6 +11,7 @@ DEFINES += QCAD_DLL
 # output directory:
 CONFIG(debug, debug|release) {
     ROUTDIR = debug
+    QMAKE_CXXFLAGS_DEBUG += -ggdb3
 } else {
     ROUTDIR = release
 }

qmake-qt4 qcad.pro CONFIG=debug

Goes on a while, then bombs off at

g++ -c -pipe -g -ggdb3 -Wall -W -fPIC -DQCAD_DLL -DPTHREADS -DHAVE_PTHREAD_H
    -I/usr/local/share/qt4/mkspecs/freebsd-g++
    -I.
    -I/usr/local/include/qt4/QtHelp
    -I/usr/local/include/qt4/QtDesigner
    -I/usr/local/include/qt4/QtUiTools
    -I../../../../core
    -I../../../../core/math
    -I../../../../grid
    -I../../../../snap
    -I../../../../gui
    -I../../../../entity
    -I../../../../operations
    -I../../../../scripting
    -I../../../../stemmer
    -I../../../../scripting/ecmaapi
    -I../../../../scripting/ecmaapi/generated
    -I../../../../scripting/ecmaapi/adapters
    -I../../../../io/dxf
    -I../../../../spatialindex
    -I../../../../3rdparty
    -I.
    -I/usr/local/include/qt4
    -I/usr/local/include
    -o debug/qtscript_Global.o
    ../../generated_cpp/com_trolltech_qt_core/qtscript_Global.cpp

../../generated_cpp/com_trolltech_qt_core/qtscript_Global.cpp:6:25: error: qmetaobject.h: No such file or directory
../../generated_cpp/com_trolltech_qt_core/qtscript_Global.cpp:8:20: error: QVariant: No such file or directory
../../generated_cpp/com_trolltech_qt_core/qtscript_Global.cpp:10:21: error: qglobal.h: No such file or directory

The corresponding good release compile line is:

g++ -c -pipe -O2 -Wall -W -pthread -D_THREAD_SAFE -fPIC -DQCAD_DLL
    -DPTHREADS -DHAVE_PTHREAD_H -DQT_NO_DEBUG -DQT_WEBKIT_LIB
    -DQT_SCRIPT_LIB -DQT_SCRIPTTOOLS_LIB -DQT_SVG_LIB -DQT_SQL_LIB
    -DQT_XMLPATTERNS_LIB -DQT_XML_LIB -DQT_OPENGL_LIB -DQT_GUI_LIB
    -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED
    -I/usr/local/share/qt4/mkspecs/freebsd-g++
    -I.
    -I/usr/local/include/qt4/QtHelp
    -I/usr/local/include/qt4/QtDesigner
    -I/usr/local/include/qt4/QtUiTools
    -I/usr/local/include/qt4/QtCore
    -I/usr/local/include/qt4/QtNetwork
    -I/usr/local/include/qt4/QtGui
    -I/usr/local/include/qt4/QtOpenGL
    -I/usr/local/include/qt4/QtXml
    -I/usr/local/include/qt4/QtXmlPatterns
    -I/usr/local/include/qt4/QtSql
    -I/usr/local/include/qt4/QtSvg
    -I/usr/local/include/qt4/QtScriptTools
    -I/usr/local/include/qt4/QtScript
    -I/usr/local/include/qt4/QtWebKit
    -I/usr/local/include/qt4
    -I../../../../core
    -I../../../../core/math
    -I../../../../grid
    -I../../../../snap
    -I../../../../gui
    -I../../../../entity
    -I../../../../operations
    -I../../../../scripting
    -I../../../../stemmer
    -I../../../../scripting/ecmaapi
    -I../../../../scripting/ecmaapi/generated
    -I../../../../scripting/ecmaapi/adapters
    -I../../../../io/dxf
    -I../../../../spatialindex
    -I../../../../3rdparty
    -I.
    -I/usr/local/include
    -Irelease
    -I/usr/local/include/qt4
    -I/usr/local/include
    -o release/qtscript_Global.o
    ../../generated_cpp/com_trolltech_qt_core/qtscript_Global.cpp

The diff between them is suspiciously big (unique items only):

includes-wise:

--- incbad      2013-10-20 11:45:37.302711863 +0200
+++ incgood     2013-10-20 11:45:31.899711566 +0200
@@ -16,7 +16,19 @@
 -I../../../../stemmer
 -I/usr/local/include
 -I/usr/local/include/qt4
+-I/usr/local/include/qt4/QtCore
 -I/usr/local/include/qt4/QtDesigner
+-I/usr/local/include/qt4/QtGui
 -I/usr/local/include/qt4/QtHelp
+-I/usr/local/include/qt4/QtNetwork
+-I/usr/local/include/qt4/QtOpenGL
+-I/usr/local/include/qt4/QtScript
+-I/usr/local/include/qt4/QtScriptTools
+-I/usr/local/include/qt4/QtSql
+-I/usr/local/include/qt4/QtSvg
 -I/usr/local/include/qt4/QtUiTools
+-I/usr/local/include/qt4/QtWebKit
+-I/usr/local/include/qt4/QtXml
+-I/usr/local/include/qt4/QtXmlPatterns
 -I/usr/local/share/qt4/mkspecs/freebsd-g++
+-Irelease

Defines-wise:

--- defbad      2013-10-20 11:51:22.405716122 +0200
+++ defgood     2013-10-20 11:52:05.362693170 +0200
@@ -1,3 +1,17 @@
 -DHAVE_PTHREAD_H
 -DPTHREADS
 -DQCAD_DLL
+-DQT_CORE_LIB
+-DQT_GUI_LIB
+-DQT_NETWORK_LIB
+-DQT_NO_DEBUG
+-DQT_OPENGL_LIB
+-DQT_SCRIPTTOOLS_LIB
+-DQT_SCRIPT_LIB
+-DQT_SHARED
+-DQT_SQL_LIB
+-DQT_SVG_LIB
+-DQT_WEBKIT_LIB
+-DQT_XMLPATTERNS_LIB
+-DQT_XML_LIB
+-D_THREAD_SAFE

qmetaobject.h is on Qt/ and QtCore/, both of which is missing from the debug include path.

On Linux, it’s complaining about QtScript/QScriptExtensionPlugin (which is in /usr/include/qt4), diffs between includes:

--- incbad      2013-10-20 12:04:32.612710645 +0200
+++ incgood     2013-10-20 12:04:58.129714235 +0200
@@ -14,7 +14,21 @@
 -I../../../../snap
 -I../../../../spatialindex
 -I../../../../stemmer
+-I/usr/X11R6/include
+-I/usr/include/qt4
+-I/usr/include/qt4/QtCore
 -I/usr/include/qt4/QtDesigner
+-I/usr/include/qt4/QtGui
 -I/usr/include/qt4/QtHelp
+-I/usr/include/qt4/QtNetwork
+-I/usr/include/qt4/QtOpenGL
+-I/usr/include/qt4/QtScript
+-I/usr/include/qt4/QtScriptTools
+-I/usr/include/qt4/QtSql
+-I/usr/include/qt4/QtSvg
 -I/usr/include/qt4/QtUiTools
+-I/usr/include/qt4/QtWebKit
+-I/usr/include/qt4/QtXml
+-I/usr/include/qt4/QtXmlPatterns
 -I/usr/share/qt4/mkspecs/linux-g++-64
+-Irelease

Defines:

--- defbad      2013-10-20 12:07:16.961712166 +0200
+++ defgood     2013-10-20 12:07:38.831670098 +0200
@@ -1,4 +1,18 @@
 -DHAVE_PTHREAD_H
 -DPTHREADS
 -DQCAD_DLL
+-DQT_CORE_LIB
+-DQT_GUI_LIB
+-DQT_NETWORK_LIB
+-DQT_NO_DEBUG
+-DQT_OPENGL_LIB
+-DQT_SCRIPTTOOLS_LIB
+-DQT_SCRIPT_LIB
+-DQT_SHARED
+-DQT_SQL_LIB
+-DQT_SVG_LIB
 -DQT_WEBKIT
+-DQT_WEBKIT_LIB
+-DQT_XMLPATTERNS_LIB
+-DQT_XML_LIB
+-D_REENTRANT

Yes, I had the ‘look for upgrades selected’ and ticked in the dialog. I only acknowledged the available update through the forum announcement made!

Arcs and circles are exported with too many segments if the drawing scale is below 1.0 (e.g. 1:100).

Screen based linetypes not working for splines, texts (CAD fonts) and dimension arrows.

Properties with title ‘Z’ are not displayed in the property editor. This is correct but should not apply to custom, user defined properties.

Points are not being exported.

If I “Trim Both” a pair of lines which already meet, then neither line changes appearance on screen (as expected). However, after saving and reloading the file, both lines are now missing.

To reproduce:

1. Create a new drawing
2. Draw a 10×10 square
3. Save the drawing
4. Close and reopen. The square shows up as expected.
5. Use the Trim Both tool on a pair of lines meeting at one of the corners. No change in the display.
6. Save the drawing
7. Close and reopen. The lines used in step 5. have disappeared.

If one or both of the lines changes length, either lengthened or shortened, then the changed line is preserved.

Build information:

Version: 3.4.2.0 (3.4.2)
Build Date: Oct 25 2013
Qt Version: 4.7.4
Compiler: MSVC++ 10.0 (2010)

Running on Windows 7 64-bit.

g++ -c -pipe -O2 -Wall -W -pthread -D_THREAD_SAFE -fPIC -DQCAD_DLL -DPTHREADS 
  -DHAVE_PTHREAD_H -DQT_NO_DEBUG -DQT_WEBKIT_LIB -DQT_SCRIPT_LIB
  -DQT_SCRIPTTOOLS_LIB -DQT_SVG_LIB -DQT_SQL_LIB -DQT_XMLPATTERNS_LIB -DQT_XML_LIB
  -DQT_OPENGL_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED
  -I/usr/local/share/qt4/mkspecs/freebsd-g++ -I. -I/usr/local/include/qt4/QtHelp
  -I/usr/local/include/qt4/QtDesigner -I/usr/local/include/qt4/QtUiTools
  -I/usr/local/include/qt4/QtCore -I/usr/local/include/qt4/QtNetwork
  -I/usr/local/include/qt4/QtGui -I/usr/local/include/qt4/QtOpenGL
  -I/usr/local/include/qt4/QtXml -I/usr/local/include/qt4/QtXmlPatterns
  -I/usr/local/include/qt4/QtSql -I/usr/local/include/qt4/QtSvg
  -I/usr/local/include/qt4/QtScriptTools -I/usr/local/include/qt4/QtScript
  -I/usr/local/include/qt4/QtWebKit -I/usr/local/include/qt4 -I../../../../core
  -I../../../../core/math -I../../../../grid -I../../../../snap -I../../../../gui
  -I../../../../entity -I../../../../operations -I../../../../scripting
  -I../../../../stemmer -I../../../../scripting/ecmaapi
  -I../../../../scripting/ecmaapi/generated
  -I../../../../scripting/ecmaapi/adapters -I../../../../io/dxf
  -I../../../../spatialindex -I../../../../3rdparty -I. -I/usr/local/include
  -Irelease -I/usr/local/include/qt4 -I/usr/local/include -o
  release/qtscript_QPinchGesture.o
  ../../generated_cpp/com_trolltech_qt_gui/qtscript_QPinchGesture.cpp
../../generated_cpp/com_trolltech_qt_gui/qtscript_QPinchGesture.cpp:53: error: 
  redefinition of 'struct QMetaTypeId<QFlags<QPinchGesture::ChangeFlag> >'
/usr/local/include/qt4/QtGui/qgesture.h:202: error: previous definition of 
  'struct QMetaTypeId<QFlags<QPinchGesture::ChangeFlag> >'
../../generated_cpp/com_trolltech_qt_gui/qtscript_QPinchGesture.cpp:240: 
  warning: 'QScriptValue qtscript_QPinchGesture_prototype_call(QScriptContext*,
  QScriptEngine*)' defined but not used
*** [release/qtscript_QPinchGesture.o] Error code 1

$ sed '202!d' /usr/local/include/qt4/QtGui/qgesture.h
Q_DECLARE_METATYPE(QPinchGesture::ChangeFlags)

$ sed '53!d' <...>/qt-labs-qtscriptgenerator-4.8.5/<...>/qtscript_QPinchGesture.cpp
Q_DECLARE_METATYPE(QFlags<QPinchGesture::ChangeFlag>)

Using Qt version 4.8.5 in /usr/local/lib/qt4.

When compiling QCAD 3.4.2.0 on Linux, the transactionlistener plugin gets installed to the wrong folder. The attached patch provides the correct directory path that trasactionlistener.so file gets installed too.

“Clip to rectangle / clear area” in combination with a Block will explode the Block and change all line attributes for the exploded ex-block.

Pics: Before / after using the tool.

See forum at:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=2640&view=unread#unread

Splines affected are 2nd degree with >4 control points, 3rd degree with >5 control points when loaded with knot vector from DXF. Newly constructed splines with automatically generated knot vector work fine.

importing a svg generated by inkscape from a downloaded eps results in all contained arcs drawn in wrong direction

When I export a bitmap from qcad, windows picture preview will not show it, instead print the message: “the file is in use by another application”. Maybe the exporter does not close the file?

When reopening a dxf that had the dimension text aligned differently than the default, the text position has the same X position for vertical dimensions and the same Y position for horizontal dimensions as the dimension line. In other words, changes to the text position are not saved or loaded when reopening a file.

For example:
1) Create the drawing and take a dimension measurement
Dimension Line on (X, Y): (110, 1680)
Text Position changed to (X, Y): (100, 1255)

2) Save file, close it and reopen it
Dimension Line on (X, Y): (110, 1680)
Text Position on (X, Y): (110, 1255)

The text height (in drawing preferences) is set to 15 and page printing scale is 1:5 (if it matters).

QCAD Professional 3.4.2.0 on Ubuntu 13.04. See the attached file for the program specs.

Not really a major bug, but quite irritating none the less. :)

Trim not working for Chamfer/Bevel or Round tools in 3.4.3.

With Trim checked nothing happens.

See:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=2681&view=unread#unread

See:
http://www.qcad.org/rsforum/viewtopic.php?f=34&t=2690

No reference Manual in 3.4.4

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=32&t=2694

Using the 32-bit linux .tar.gz package on Opensuse 12.3 - KDE4, it opens with a window size larger than the screen (you cannot reach the maximise, minimise icons with the mouse.
Having maximised it with the keyboard, using the mouse on the corners the window can only be stretched in the east-west dimension and remains at a fixed height. I have reverted to 3.4.2 which is fine.

Bob

Not sure whether this has been reported yet.
I get an unexpected result when creating a solid fill hatch in an isometric projection, all entities are polylines.

Example: file name: “my.file.dxf” File - Save As suggests file name: “my.dxf”

If I have multi lines with different heights in a Rich Text the scale tool works not at all or the scale factor works different on each lines.

This example is scaled with factor 2. First line works - second line keeps the proportions.

Hello,
I’m still evaluating qcad, and am currently working on some competition drawings.
Positive things first:
The respective drawing (a site plan delivered by the city authorities) containes one big solid hatch that is made of hundreds of closed boundaries. While this brought BricsCAD (my main program) to its knees, qcad handles this file with complete ease, congratulations!

But after some hours of work, I stumbled over a quite nasty bug: I tried to draw a polyline in model space, and got a “transaction failed” message (although the current layer was not locked) and then suddenly all entities in the drawing just disappeared. I checked my block definitions, and they too were empty. I therefore saved the drawing under a new name and closed it. However, there was no sign of qcad becoming unstable - it opened the previous version of the file without problems (I restarted the program nonetheless...).

Attached are the empty file (V1-2_corrupted.dwg), the last intact save before (V1-2.dwg), and logs of the command line as well as of the console.

Running audit in BricsCAD on V1-2.dwg just lists 57 errors like this:
Name: AcDbTextStyleTableRecord(6446)
Value: Last height 0
Validation: Not >0
Default value: Set to 2.5

Hope this can give some hints - if not, don’t waste time on it, I would come back to it should I encounter such a problem again.

I have a dimension layer on a drawing. I make only that layer visible and select all dimensions. Then from the property editor I set the Linear Factor. The dimension values change as expected, and I can print the drawing and have the new dimension values show up as expected. When I save and close the drawing, then re-open it, the dimension Linear Factor does not retain the value I gave it. I saved my drawing in the current R27 DXF format.

Both community and Git head, on Linux and FreeBSD.

Not sure how to describe the odd behaviour... Draw something with a couple of colors, turn on Print preview, then modify Drawing prefs/Print/Colors/Color mode several times, setting it to a different mode than what it is currently, Apply, OK.

What happens is sometimes it doesn’t change (that is, the next time this preference is opened, it is still at Full Color even if I have just clicked, applied and OK’d Grayscale etc.).

Further, it seems that the selection is not reflected at the print preview view, or rather, it is off by one – if I finally manage to switch to Grayscale, it stays Full Color. Then if I somehow manage to switch to Black/white, the print preview changes to Grayscale etc.

I can try to make a screen movie if necessary.