Swing charts with a translucent surface let the previous view content appear under the surface

[jzy3d]

Version : jzy3d-2.1.1-SNAPSHOT
Date : 2022-07-28
Factory : SwingChartFactory (does not occur on AWT)

Reproduce

Only happens with SwingChartFactory.

• Display a surface with alpha < 1
• Enable view3d() then render()
• Enable view2d() then render()

• Then resize() to let a colorbar glitch appear

Workaround

Workaround 1 : render multiple time

Call chart.render(2); after chart.view2d(...)
Rendering only once still let use see a bit of the previous image (!?).

Workaround 2 : disable alpha

Alpha is not useful when viewing a surface on top if the chart has no other element inside.

Investigated

The following have been investigated but are NOT the reason of the bug :

• Changing GLCapabilities.setBackgroundOpaque(true/false) in NativePainterFactory
• Changing GLCapabilities.setDoubledBuffer(true/false) in NativePainterFactory
• Changing setAutoSwapBuffer(true/false) in CanvasSwing
• Changing the depth buffer clear value in View.clear
• Changing the static White Color set to View.setBackground in the Chart constructor to a copy of the color won't change anything

Other thoughts

• The fact that AWT works proves that there is no OpenGL misconfiguration (e.g. no reason to think that the depth buffer is not cleared)

Links

• Discussion on JOGL forum