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Qt5.6 application : red and blue colors swapped

  • Hello,

    I recently compiled qt5.6 with the configuration bellow. I am having a simple application that is using qtwebkit to display an url page on a lcd display. The webpages displayed have red and blue colors swapped. The qt engine is using the linux framebuffer.
    If I set the number of bits per pixel to 16, the webpages are properly displayed.
    echo 16 > /sys/class/graphics/fb0/bits_per_pixel

    The number of bits per pixel by default is 24 and I would like to use this value instead of 16.
    I have also attached the framebuffer information bellow.

    qt 5.6 configuration options
    ./configure -v -opensource -arch arm -opengl es2 -egl -no-fontconfig -confirm-license -debug -verbose -device imx6 -device-option CROSS_COMPILE=arm-linux-gnu- -sysroot /home/fmaticu/sysroot -optimized-qmake -reduce-exports -gstreamer 1.0

    Frame buffer information
    mode "1920x1080-60"
    # D: 148.500 MHz, H: 67.500 kHz, V: 60.000 Hz
    geometry 1920 1080 1920 2160 24
    timings 6734 148 88 36 4 44 5
    hsync high
    vsync high
    rgba 8/16,8/8,8/0,0/0

    Frame buffer device information:
    Name : DISP3 BG
    Address : 0x29400000
    Size : 12441600
    Visual : TRUECOLOR
    XPanStep : 1
    YPanStep : 1
    YWrapStep : 1
    LineLength : 5760
    Accelerator : No

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    Since you are using an unreleased version of Qt and hitting something that's probably influenced by the internals of Qt. I'd recommend posting your question on the interest mailing list You'll find there Qt's developers/maintainers (this forum is more user oriented)