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opengl1.5 and ppointer?
https://delphigl.com/forum/viewtopic.php?f=19&t=1972
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Autor:  noeska [ Sa Okt 04, 2003 22:33 ]
Betreff des Beitrags:  opengl1.5 and ppointer?

What is a ppointer?

I tried using the opengl 1.5 units, but it could not compile. Only after commenting out the lines that contained ppointer i was able to compile it.

I can think of it as an pointer to an pointer, but why would one use such an construction?

Autor:  Sascha Willems [ Sa Okt 04, 2003 22:40 ]
Betreff des Beitrags: 

Yes, a PPointer is a pointer to a pointer and although it won't make much sense in the first place, a pointer to a pointer is a widely used concept (in C++ more, in Delphi less) so it's nothing special.Under Delphi7 this PPointer is defined in the system.pas so just put PPointer = ^Pointer somewhere at the beginning of our dglOpenGL.pas and it should work.
As far as I've looked through our unit this pointer to a pointer is only used by two functions for the glutesselator, and maybe it's there because they store something this way.But as it's nothing important you shouldn't worry too much.

Autor:  wic [ So Okt 05, 2003 18:52 ]
Betreff des Beitrags: 

for instance, a pointer to pointer structure is used for
building/handling a kind of a pointer array


char **argv or char *argv[]
|
v
[p]-->[szAppParam1] (pointer to zero terminated string)
[p]-->[szAppParam2]
[p]-->[szAppParam3]
[p]-->[szAppParam4]

you can iterate through the strings by argv++ selecting the next pointer to szAppParamN from the "array"

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