I add this screenshot to show exactly what is happening. My web browser was in background when I launched monteverdi. Reproduced on a regular OTB build, Ubuntu 14.04, Runtime OpenGL version '3.0 Mesa 10.1.3' with GLSL version '1.30', and Qt 5.2.1.
I can't reproduce this on 6.4. Are 6.6 binary packages available somewhere?
Can't reproduce it on 6.6 under Arch Linux, GNOME Shell, neither Wayland, nor Xorg. Do you see anything if you run it with MESA_DEBUG=1 LIBGL_DEBUG=verbose?
Codec for Locale: "UTF-8" Language: "English" Country: "UnitedStates" Settings/GeoidFile: "/home/gpasero/Projet_OTB/src/OTB-Data/Input/DEM/egm96.grd" Settings/DEMDir: "/home/gpasero/Projet_OTB/src/OTB-Data/Input/DEM/srtm_directory" libGL: screen 0 does not appear to be DRI3 capablelibGL: pci id for fd 17: 8086:0416, driver i965libGL: OpenDriver: trying /usr/lib/x86_64-linux-gnu/dri/tls/i965_dri.solibGL: OpenDriver: trying /usr/lib/x86_64-linux-gnu/dri/i965_dri.solibGL: Can't open configuration file /home/gpasero/.drirc: No such file or directory.libGL: Can't open configuration file /home/gpasero/.drirc: No such file or directory.WARNG> Runtime version of OpenGL used by Qt 5.2.1: 3.0. libGL: Can't open configuration file /home/gpasero/.drirc: No such file or directory.WARNG> Version(s) of OpenGL supported by Qt 5.2.1: WARNG> - QGLFormat::OpenGL_Version_3_3 WARNG> - QGLFormat::OpenGL_Version_3_2 WARNG> - QGLFormat::OpenGL_Version_3_1 WARNG> - QGLFormat::OpenGL_Version_3_0 WARNG> - QGLFormat::OpenGL_Version_2_1 WARNG> - QGLFormat::OpenGL_Version_2_0 WARNG> - QGLFormat::OpenGL_Version_1_5 WARNG> - QGLFormat::OpenGL_Version_1_4 WARNG> - QGLFormat::OpenGL_Version_1_3 WARNG> - QGLFormat::OpenGL_Version_1_2 WARNG> - QGLFormat::OpenGL_Version_1_1 libGL: Can't open configuration file /home/gpasero/.drirc: No such file or directory.WARNG> Runtime version of OpenGL used by Qt 5.2.1: 3.0. WARNG> Version(s) of OpenGL supported by Qt 5.2.1: WARNG> - QGLFormat::OpenGL_Version_3_3 WARNG> - QGLFormat::OpenGL_Version_3_2 WARNG> - QGLFormat::OpenGL_Version_3_1 WARNG> - QGLFormat::OpenGL_Version_3_0 WARNG> - QGLFormat::OpenGL_Version_2_1 WARNG> - QGLFormat::OpenGL_Version_2_0 WARNG> - QGLFormat::OpenGL_Version_1_5 WARNG> - QGLFormat::OpenGL_Version_1_4 WARNG> - QGLFormat::OpenGL_Version_1_3 WARNG> - QGLFormat::OpenGL_Version_1_2 WARNG> - QGLFormat::OpenGL_Version_1_1 WARNG> Required OpenGL version '2.0.0' with GLSL version '1.20'. WARNG> Runtime OpenGL version '3.0 Mesa 10.1.3' with GLSL version '1.30'.
To sum up, it looks like an issue on Qt5/OpenGL side, where a rendering sequence without any feature drawn is not enough to initialize properly the display area.
The only fix I found so far is to draw a dummy point in the first 2 rendering sequences.
If I am the only one affected by this bug, we may consider not fixing it.