Python Pyqtgraph scatter white backgroundcolor issue

[ymmx]

I've got an issue when using the pyqtgraph module in python. When I put a white backgrouncolor to a glscatterplot, the scatter dots just vanish. It is like if the color of background was added to the color of the scatterplot therefore everything is white. Here is a piece of the code I use:

w = gl.GLViewWidget()
w.setBackgroundColor('w')
w.show()
sp3 = gl.GLScatterPlotItem(pos=np.transpose(pos3), color=rgba_img, size=1, pxMode=False)
w.addItem(sp3)

If I replace ('w') by ('k') in the setBackgroundColor method the color of scatter is fine, with a black background. did anybody ever get this issue and found a solution to it?

[ixjlyons]

There is an option for GLScatterPlotItem called glOptions. By default, 'additive' is used (see pyqtgraph.opengl.GLGraphicsItem.GLOptions), so depth testing is disabled. You can change it to 'translucent' like so:

scatterPlotItem.setGLOptions('translucent')

I tested this in the 3D graphics scatter plot example with a white background, and it worked fine. Clouds of points don't look as good as they do with the 'additive' option and a black background, however.

It's more of a workaround than a fix, but I'm not sure what the correct solution is. Perhaps 'additive' could remain as the default, but there should probably be some mention of this in the docs -- maybe in the setBackgroundColor() docstring.

edit: Also, note that there is a bug in GLViewWidget which incorrectly sets the background color (see #194), so only "pure" colors like black, white, red, green, etc. will work.

[ymmx]

Great, that's work well. This is tricky to find so ;)
Thank you alot