+ improve OCC version macro, fix build failure with MinGW, fix build failure with Coin2

cMake/FreeCadMacros.cmake

@@ -255,9 +255,9 @@ MACRO(SET_PYTHON_PREFIX_SUFFIX ProjectName)
 ENDMACRO(SET_PYTHON_PREFIX_SUFFIX)
 
 MACRO(CHECK_MINIMUM_OCC_VERSION_HEX MinVersionHex)
+    message(STATUS "Check for OCC version >= ${MinVersionHex}")
     set(CMAKE_REQUIRED_INCLUDES ${OCC_INCLUDE_DIR})
     unset(OCC_MIN_VERSION CACHE)
-    set(OCC_CHECK_VERSION 0x060600)
     CHECK_CXX_SOURCE_RUNS("
         #include <Standard_Version.hxx>
         int main ()

src/App/Application.cpp

@@ -34,6 +34,9 @@
 # include <unistd.h>
 # include <pwd.h>
 # include <sys/types.h>
+# elif defined(__MINGW32__)
+# define WINVER 0x502 // needed for SetDllDirectory
+# include <Windows.h>
 # endif
 # include <ctime>
 # include <csignal>

src/Mod/Sketcher/Gui/ViewProviderSketch.cpp

@@ -32,6 +32,7 @@
 # include <Inventor/actions/SoGetBoundingBoxAction.h>
 # include <Inventor/SoPath.h>
 # include <Inventor/SbBox3f.h>
+# include <Inventor/SbImage.h>
 # include <Inventor/SoPickedPoint.h>
 # include <Inventor/details/SoLineDetail.h>
 # include <Inventor/details/SoPointDetail.h>
@@ -1685,13 +1686,22 @@ bool ViewProviderSketch::detectPreselection(const SoPickedPoint *Point,
 
 SbVec3s ViewProviderSketch::getDisplayedSize(const SoImage *iconPtr) const
 {
+#if (COIN_MAJOR_VERSION >= 3)
     SbVec3s iconSize = iconPtr->image.getValue().getSize();
+#else
+    SbVec2s size;
+    int nc;
+    const unsigned char * bytes = iconPtr->image.getValue(size, nc);
+    SbImage img (bytes, size, nc);
+    SbVec3s iconSize = img.getSize();
+#endif
     if (iconPtr->width.getValue() != -1)
         iconSize[0] = iconPtr->width.getValue();
     if (iconPtr->height.getValue() != -1)
         iconSize[1] = iconPtr->height.getValue();
     return iconSize;
 }
+
 void ViewProviderSketch::doBoxSelection(const SbVec2s &startPos, const SbVec2s &endPos,
                                         const Gui::View3DInventorViewer *viewer)
 {