QQuickPaintedItem with width or height bigger than 2048 doesn't show on Arm Linux

noarrt

It took me a while to figure out why my QQuickPaintedItem isn't shown on Arm Linux while it IS shown on Windows - eventually after tinkering with many properties I came to the conclusion that if it's width (or height) are wider than 2048 - it won't be shown.

This is a change that came with Qt 5 QtQuick 2, in Qt 4.8 QtQuick 1 I used a DeclarativeItem for the same painted width and it worked just fine.

Does anyone have a clue how to begin to solve this?

Thanks!

andre

Sounds like a limitation of your openGL stack on your arm system. No clue how to get around that, I don't know enough about openGl to be of assistance with that.

onek24

Have you tried it with a smaller image, so we can narrow the possible faults.

noarrt

Andre - will look into this, thank you

one - yes, I have been tinkering with the sizes, the item vanishes and leaves a black backdrop when the width or height fo over 2k - 2048

onek24

Alright, could you please create a Image with its width or height over 2k and scale it down to about 0.5 or 50% of its normal Size. Is it still black or does it display the Image?

noarrt

Thanks - scaled down it still isn't displayed and shows black

onek24

Okay, it doesn't seems like the Problem is the opengl stack. Since i remember your imageprovider would provide a new image in the scaled size, so the image would be smaller than 2k and the opengl stack could show it. The problem should be your imageprovider. It seems like he cant properly load images bigger than 20002000 or 4 Megapixels. I haven't worked with QQuickPaintedItem yet so i probably can't help you, but i will try to.
Oh and another thing, could you please load a Image smaller than 2k2k, for example 10241024 and scale it up to about 20482048 or more and post what happened.

noarrt

Did it just now, 1024 scaled 3 - it shows

onek24

Alright then it is not your opengl-stack. I'm not sure about the problem but it probably is some bug or some arm-unsupported stuff in your imageprovider. Please feel free to post your issue here: "Bugreports":https://bugreports.qt-project.org/issues/?jql=