#13340: BGLView::GetGLProcAddress and eglGetProcAddress return NULL always
-------------------------------+----------------------------
Reporter: waddlesplash | Owner: kallisti5
Type: bug | Status: new
Priority: normal | Milestone: Unscheduled
Component: Kits/OpenGL Kit | Version: R1/Development
Resolution: | Keywords:
Blocked By: | Blocking:
Has a Patch: 0 | Platform: All
-------------------------------+----------------------------
Comment (by Duggan):
I can't find where in the Dolphin sources it calls cInterfaceBGL::Create()
but I believe it calls GetGLProcAddress() either in the same function or
at least in the same thread without break.
GetGLProcAddress() depends on the BGLDispatcher which is retrieved from
the BGLRenderer(fRenderer)
{{{
void*
BGLView::GetGLProcAddress(const char* procName)
{
BGLDispatcher* glDispatcher = NULL;
if (fRenderer)
glDispatcher = fRenderer->GLDispatcher();
if (glDispatcher)
return (void*)glDispatcher->AddressOf(procName);
return NULL;
}
}}}
The renderer is not set until AttachedToWindow()
{{{
void
BGLView::AttachedToWindow()
{
BView::AttachedToWindow();
fBounds = Bounds();
for (BView* view = this; view != NULL; view = view->Parent())
view->ConvertToParent(&fBounds);
fRenderer = fRoster->GetRenderer();
if (fRenderer != NULL) {
}}}
while the GLRendererRoster it depends on is set in the constructor
{{{
BGLView::BGLView(BRect rect, const char* name, ulong resizingMode, ulong
mode,
ulong options)
:
BView(rect, name, B_FOLLOW_ALL_SIDES, mode | B_WILL_DRAW |
B_FRAME_EVENTS),
// | B_FULL_UPDATE_ON_RESIZE)
fGc(NULL),
fOptions(options),
fDitherCount(0),
fDrawLock("BGLView draw lock"),
fDisplayLock("BGLView display lock"),
fClipInfo(NULL),
fRenderer(NULL),
fRoster(NULL),
fDitherMap(NULL)
{
fRoster = new GLRendererRoster(this, options);
}
}}}
I don't know why fRenderer is not also set in the constructor, but I
assume for a reason, perhaps to prevent unattached views from stealing CPU
cycles. Regardless, if GetGLProcAddress() is called before the
AttachedToWindow() callback has time to execute, fRenderer will be NULL,
and as a result, GetGLProcAddress() will fail.
If this is indeed the case, the best solution may be to either inherit
from BGLView and override the constructor and AttachedToWindow()
functions, or it may just be easier (due to dependencies) to copy and
paste the files and rename the class, changing the location of the one
line... a little messy, but it should work fine.
The BGLView sources are located in the Mesa repo. If you need any
additional help or if this doesn't solve the problem, let me know!
--
Ticket URL: <https://dev.haiku-os.org/ticket/13340#comment:1>
Haiku <https://dev.haiku-os.org>
The Haiku operating system.
