Qwt multiaxis bug - can't set color for OpenGL canvas

Dear Uwe,

I'm trying to change background color of QwtPlotOpenGLCanvas from black to white but it doesn't seem to work in multiaxis branch. By the way previously I worked with Qwt from trunk and there it worked fine.

Code:

---

QwtPlot* plot = new QwtPlot;
    QwtPlotOpenGLCanvas *canvas = new QwtPlotOpenGLCanvas(); // NEW OpenGL Canvas
    plot->setCanvasBackground( Qt::white );
    plot->setCanvas(canvas);

---

the canvas is black

Call setCanvas before calling setCanvasBackground.

HTH,
Uwe

That doesn't help (see picture).

Code:

---

QwtPlotOpenGLCanvas *canvas = new QwtPlotOpenGLCanvas(); // NEW OpenGL Canvas
    upperPlot->setCanvas(canvas);
    upperPlot->setCanvasBackground( Qt::white );

---

By the way these lines of code invoke the warning:
DXGI WARNING: IDXGIFactory::CreateSwapChain: Blt-model swap effects (DXGI_SWAP_EFFECT_DISCARD and DXGI_SWAP_EFFECT_SEQUENTIAL) are legacy swap effects that are predominantly superceded by their flip-model counterparts (DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL and DXGI_SWAP_EFFECT_FLIP_DISCARD). Please consider updating your application to leverage flip-model swap effects to benefit from modern presentation enhancements. More information is available at http://aka.ms/dxgiflipmodel. [ MISCELLANEOUS WARNING #294: ]
Attachment 13494

On my linux box the background is white, when using your code - I don't have any Windows systems available.
Concerning the warnings: Qwt does not do any native calls, everything is done via Qt APIs.

But, what happens, when using Qwt from trunk - the code for the opengl canvas is different there and has not yet been ported to the multiaxes branch ?

Uwe

I think yes, I've installed Qwt from trunk about two months ago and there is no opportunity to use multiaxes. Everything else is fine with Qwt from trunk I think

What about the 6.2 branch - it should have the same OpenGL canvas code as the one from the multiaxes branch ?

Uwe

I've just installed Qwt-6.2.0-svn and there is no neither qwt_plot_opengl_canvas.h or plot->setAxesCount
Here is the link where I downloaded it: https://sourceforge.net/p/qwt/code/H...nches/qwt-6.2/

Ah yes, the opengl canvas code of the multiaxes branch is indeed the same as the one in trunk - 6.2 is an older version. So when your code is working with trunk there is no technical reason why it should not work with multiaxes.

Uwe

it is strange...