radialWipe randomly inverts itself on iPad?

Solar2D Custom Shader Effects
#1

We have tried using a radialWipe filter to create a kind of “pie chart” that fills up over time. On the simulator and Android this seems to work fine. On an iPad 3 it works ok, but on an iPad Air we see a weird effect where the radialWipe decides to invert the opaque/transparent sections.

You can see the effect here: https://www.youtube.com/watch?v=EeByYuer9JY

The piechart can be seen filling behind the number 1, and occasionally jumps to an inverted state. I have printed out the progress values being used, and they go from 1 to 0 as expected. 

The progress is being updated in an enterframe loop, nothing strange happening there.  

The only thing that could be considered non-standard is that I had to flip the xScale of the object to -1 and make the progress go from 1 to 0 instead of 1 to 0, because we wanted the opaque section to fill clockwise, not the transparent section.  

I don’t see any reason why that would cause this weird inversion to happen though, as we do not change the xScale value at all after the object is initially created.

Does anyone have any ideas?

#2

This sounds like a bug. But I might be able to suggest a work around. Instead of using an xScale of -1, how about you try reversing the colors to appear the as you would like. i.e. If you have pink over yellow, instead use yellow over pink and change the way you adjust the wipe. Instead of 1 to 0, use 0 to 1, or vice versa. Or whatever. Just ideas.

#3

Pretty sure it is a bug, as it only happens on certain devices I’m guessing it’s a GPU issue or something like that.  

You’re idea could work, our shape is actually just one colour with transparency, but I suppose we could make it a solid circle and then do a radial wipe on another object over the top, which is the same colour as the background. 

Would rather know if the filter has a fixable bug though of course.

#4

Can you file a bug report please? Create a simple example that demonstrates the problem. The project must have a main.lua, config.lua and build.settings and any assets needed for it to run. Put all of that in a .zip file and use the Report a bug feature at the top of this page. Once you’ve successfully filed it, you will get a confirmation mail.  Please post the CaseID # back here.

You can also attach the video which will help too.

Rob

#5

This sounds like a bug. But I might be able to suggest a work around. Instead of using an xScale of -1, how about you try reversing the colors to appear the as you would like. i.e. If you have pink over yellow, instead use yellow over pink and change the way you adjust the wipe. Instead of 1 to 0, use 0 to 1, or vice versa. Or whatever. Just ideas.

#6

Pretty sure it is a bug, as it only happens on certain devices I’m guessing it’s a GPU issue or something like that.  

You’re idea could work, our shape is actually just one colour with transparency, but I suppose we could make it a solid circle and then do a radial wipe on another object over the top, which is the same colour as the background. 

Would rather know if the filter has a fixable bug though of course.

#7

Can you file a bug report please? Create a simple example that demonstrates the problem. The project must have a main.lua, config.lua and build.settings and any assets needed for it to run. Put all of that in a .zip file and use the Report a bug feature at the top of this page. Once you’ve successfully filed it, you will get a confirmation mail.  Please post the CaseID # back here.

You can also attach the video which will help too.

Rob