5.71LTS OpenGL Gadget back colour lost on Window Restore

[IdeasVacuum]

Windows 7/10 x64

If a Window containing an OpenGL Gadget is minimised, on restore the OpenGL Gadget back colour becomes that of the Window back colour.

Work around is to apply glClearColor, glClear and SetGadgetAttribute #PB_OpenGL_FlipBuffers (e.g. using a Macro)

[Fred]

An OpenGLGadget() is not double buffered and can't redraw automatically its last buffer (unless I miss something in OpenGL API), so you need to redraw it when the window size change on Windows. I updated the doc.

[Olli]

(lots of communication attacks... no links with the forum)

I confirm the "redraw". I suggest grab from draw to video memory (gl function).

I have a small example about resizing glGadget, I must refind.

[Mijikai]

Mby we can test it like this:

Code: Select all

Procedure.i HasDoubleBuffer()
  Protected hdc.i
  Protected pfd.PIXELFORMATDESCRIPTOR
  hdc = wglGetCurrentDC_()
  If DescribePixelFormat_(hdc,GetPixelFormat_(hdc),SizeOf(PIXELFORMATDESCRIPTOR),@pfd)
    ProcedureReturn Bool(pfd\dwFlags & #PFD_DOUBLEBUFFER)
  EndIf
  ProcedureReturn #False
EndProcedure

[Olli]

@mijikai

I am not sure it is useful in the way where a window (a view gadget) is resizing.

-> How could the API adapt a new set of dimension through two buffers ?
-> In the way where the scale is kept (that was my way), the matrix changes.