New custom widgets for Float and Int parameters

Summary

Rewrite numerical parameter widgets of otbgui to provide several improvements.

Before:

After:

• Add a new "clear" button, visible only when applicable, inspired by QGIS's QgsSpinBox
• Remove the reset button
• Disable the scroll wheel event to avoid conflict with the parent QScrollArea
• Use variable length decimal input to avoid ugly trailing zeros.
• Fix the Qt issue where the user could not type digits because the spinbox was already full.
• Fix user value flag not reset when reset button is pressed
• Fix DoUpdateGUI spaghetti code (don't call it on children in QtWidgetGroupParameter)
• Don't highlight on select
• Only call application's DoUpdateParameters when editing is finished, not on every keystroke.
• Add Qt5Svg dependency to SuperBuild (needed to read the svg icon file).

Rationale

Better otbgui UX.

Implementation Details

Classes and files

M       Modules/ThirdParty/Qt/CMakeLists.txt
M       Modules/ThirdParty/Qt/otb-module-init.cmake
M       Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetFloatParameter.h
M       Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetIntParameter.h
M       Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetModel.h
M       Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetParameterBase.h
A       Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetSpinBoxes.h
M       Modules/Wrappers/QtWidget/src/CMakeLists.txt
M       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetFloatParameter.cxx
A       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetIcons.qrc
M       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetIntParameter.cxx
M       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetParameterBase.cxx
M       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetParameterGroup.cxx
A       Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetSpinBoxes.cxx
M       SuperBuild/CMake/External_qt5.cmake
A       Utilities/Data/Icons/mIconClearText.svg
A       Utilities/Data/Icons/mIconClearTextHover.svg

Applications

NA.

Tests

NA.

Documentation

NA.

Additional notes

• There is a significant amount of duplicated code between otbWrapperQtWidgetIntParameter and otbWrapperQtWidgetFloatParameter. This is not addressed by this MR. Unfortunately I think that the fix is more complex than simply moving the common code to a base class. Might be possible with multiple inheritance of an interface common to QtWidgetSpinBox and QtWidgetDoubleSpinBox.
• The new float widget does not show decimal points for float values that are also integers. This may confuse users who will not figure out that they are allowed to input non-integer values. Similarly, because the new LineEdit allows all input and only clears it when focus is lost, users might enter decimal values in int parameter, only to be confused why their input is being truncated.
• As a fundamental limitation of IEEE float, there will be loss of precision (and therefore weird GUI behavior) beyond 6 decimal digits in float inputs. It is not possible to go around this without also changing application engine's floats to doubles.

Copyright

The copyright owner is CNES and has signed the ORFEO ToolBox Contributor License Agreement