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Link error with programs compiled without OpenGL
Emmanuel Gil Peyrot
Guest
Post Posted: Thu May 09, 2013 12:48 am
Hi,

I have found that latest SDL 2.0 includes a change that force programs
to be linked against the libGL (or any other one that provide glEnable,
glScissor and glDisable). I bisected and fount it was the changeset
e276777b4247 (7141 here), if someone want to look at how it added that
dependency and remove it -I take it shouldn’t be there in the first
place.

The error is as follow when linking any program against SDL2:
/usr/lib/libSDL2.so: undefined reference to `glScissor'
/usr/lib/libSDL2.so: undefined reference to `glEnable'
/usr/lib/libSDL2.so: undefined reference to `glDisable'

changeset: 7141:e276777b4247
user: Sam Lantinga
date: Sat May 04 04:46:00 2013 -0700
summary: First pass on SDL render clip rect functionality

--
Emmanuel Gil Peyrot
XMPP:
OpenPGP: 24B1D609

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Link error with programs compiled without OpenGL
Emmanuel Gil Peyrot
Guest
Post Posted: Fri May 10, 2013 12:01 pm
On Thu, May 09, 2013 at 02:48:19AM +0200, Emmanuel Gil Peyrot wrote:
Quote:
Hi,

I have found that latest SDL 2.0 includes a change that force programs
to be linked against the libGL (or any other one that provide glEnable,
glScissor and glDisable). I bisected and fount it was the changeset
e276777b4247 (7141 here), if someone want to look at how it added that
dependency and remove it -I take it shouldn’t be there in the first
place.
[snip]

Here is a fix, the issue was that the gl* functions were used instead
of taking them from the GLES/GLES2 renderer.

http://linkmauve.fr/files/fix-7141.patch

--
Emmanuel Gil Peyrot
XMPP:
OpenPGP: 24B1D609

_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
Link error with programs compiled without OpenGL
Martin Gerhardy
Guest
Post Posted: Fri May 10, 2013 12:41 pm
Am 10.05.2013 14:01, schrieb Emmanuel Gil Peyrot:

Quote:
Quote:
On Thu, May 09, 2013 at 02:48:19AM +0200, Emmanuel Gil Peyrot wrote:
Quote:
Hi,

I have found that latest SDL 2.0 includes a change that force programs
to be linked against the libGL (or any other one that provide glEnable,
glScissor and glDisable). I bisected and fount it was the changeset
e276777b4247 (7141 here), if someone want to look at how it added that
dependency and remove it -I take it shouldn’t be there in the first
place.
[snip]

Here is a fix, the issue was that the gl* functions were used instead
of taking them from the GLES/GLES2 renderer.

http://linkmauve.fr/files/fix-7141.patch


Quote:
_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
The glScissor calls are wrong, too? The rect is not given in x, y, w, h to glScissor.
Link error with programs compiled without OpenGL
gabomdq


Joined: 28 Jul 2011
Posts: 495
Location: Argentina
Post Posted: Fri May 10, 2013 12:51 pm
2013/5/10 Martin Gerhardy
Quote:
Am 10.05.2013 14:01, schrieb Emmanuel Gil Peyrot:

Quote:
Quote:
On Thu, May 09, 2013 at 02:48:19AM +0200, Emmanuel Gil Peyrot wrote:
Quote:
Hi,

I have found that latest SDL 2.0 includes a change that force programs
to be linked against the libGL (or any other one that provide glEnable,
glScissor and glDisable). I bisected and fount it was the changeset
e276777b4247 (7141 here), if someone want to look at how it added that
dependency and remove it -I take it shouldn’t be there in the first
place.
[snip]

Here is a fix, the issue was that the gl* functions were used instead
of taking them from the GLES/GLES2 renderer.

http://linkmauve.fr/files/fix-7141.patch


Quote:
_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
The glScissor calls are wrong, too? The rect is not given in x, y, w, h to glScissor.


And I think it also doesn't translate the convention from SDL coordinates (origin at top, left) to OpenGL (origin at bottom,left).




--
Gabriel.
Link error with programs compiled without OpenGL
Mason Wheeler
Guest
Post Posted: Fri May 10, 2013 1:08 pm
Wow, who wrote the patch in question? I sure hope it wasn't me... o_0


Mason



From: Gabriel Jacobo
To: SDL Development List
Sent: Friday, May 10, 2013 5:51 AM
Subject: Re: [SDL] Link error with programs compiled without OpenGL





2013/5/10 Martin Gerhardy
Quote:
Am 10.05.2013 14:01, schrieb Emmanuel Gil Peyrot:

Quote:
Quote:
On Thu, May 09, 2013 at 02:48:19AM +0200, Emmanuel Gil Peyrot wrote:
Quote:
Hi,

I have found that latest SDL 2.0 includes a change that force programs
to be linked against the libGL (or any other one that provide glEnable,
glScissor and glDisable). I bisected and fount it was the changeset
e276777b4247 (7141 here), if someone want to look at how it added that
dependency and remove it -I take it shouldn’t be there in the first
place.
[snip]

Here is a fix, the issue was that the gl* functions were used instead
of taking them from the GLES/GLES2 renderer.

http://linkmauve.fr/files/fix-7141.patch


Quote:
_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
The glScissor calls are wrong, too? The rect is not given in x, y, w, h to glScissor.


And I think it also doesn't translate the convention from SDL coordinates (origin at top, left) to OpenGL (origin at bottom,left).




--
Gabriel.



_______________________________________________
SDL mailing list

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Link error with programs compiled without OpenGL
Emmanuel Gil Peyrot
Guest
Post Posted: Fri May 10, 2013 1:13 pm
On Fri, May 10, 2013 at 09:51:47AM -0300, Gabriel Jacobo wrote:
Quote:
2013/5/10 Martin Gerhardy
[snip]
Quote:
Quote:
The glScissor calls are wrong, too? The rect is not given in x, y, w, h
to glScissor.

True, I didn’t look at the arguments at all, assuming they were
correct. It seems they used the same coordinates as the d3d renderer.

Quote:
And I think it also doesn't translate the convention from SDL coordinates
(origin at top, left) to OpenGL (origin at bottom,left).

I fixed that in my latest patch[1].

[1] http://linkmauve.fr/files/fix-7141.patch

--
Emmanuel Gil Peyrot
XMPP:
OpenPGP: 24B1D609

_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
Link error with programs compiled without OpenGL
gabomdq


Joined: 28 Jul 2011
Posts: 495
Location: Argentina
Post Posted: Fri May 10, 2013 1:31 pm
2013/5/10 Emmanuel Gil Peyrot
Quote:
On Fri, May 10, 2013 at 09:51:47AM -0300, Gabriel Jacobo wrote:
Quote:
2013/5/10 Martin Gerhardy
[snip]
Quote:
Quote:
 The glScissor calls are wrong, too? The rect is not given in x, y, w, h
to glScissor.

True, I didn’t look at the arguments at all, assuming they were
correct.  It seems they used the same coordinates as the d3d renderer.

Quote:
And I think it also doesn't translate the convention from SDL coordinates
(origin at top, left) to OpenGL (origin at bottom,left).

I fixed that in my latest patch[1].

[1] http://linkmauve.fr/files/fix-7141.patch


Thanks! http://hg.libsdl.org/SDL/rev/bfb5f8f4f006



--
Gabriel.
Link error with programs compiled without OpenGL
Martin Gerhardy
Guest
Post Posted: Fri May 10, 2013 7:06 pm
Am 10.05.2013 15:13, schrieb Emmanuel Gil Peyrot:
Quote:
On Fri, May 10, 2013 at 09:51:47AM -0300, Gabriel Jacobo wrote:
Quote:
2013/5/10 Martin Gerhardy
[snip]
Quote:
Quote:
The glScissor calls are wrong, too? The rect is not given in x, y, w, h
to glScissor.
True, I didn’t look at the arguments at all, assuming they were
correct. It seems they used the same coordinates as the d3d renderer.

Quote:
And I think it also doesn't translate the convention from SDL coordinates
(origin at top, left) to OpenGL (origin at bottom,left).
I fixed that in my latest patch[1].

[1] http://linkmauve.fr/files/fix-7141.patch

sorry, but this is still not correct.

you have to do:

int lowerLeft = window->height - rect.y - rect.height;
glScissor(rect.x, lowerLeft, rect.width, rect.height);

I hope there is no typo in this... and I hope I'm right with this ;)

Greetings
Martin

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SDL mailing list

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Link error with programs compiled without OpenGL
gabomdq


Joined: 28 Jul 2011
Posts: 495
Location: Argentina
Post Posted: Fri May 10, 2013 7:15 pm
2013/5/10 Martin Gerhardy
Quote:
Am 10.05.2013 15:13, schrieb Emmanuel Gil Peyrot:
Quote:
On Fri, May 10, 2013 at 09:51:47AM -0300, Gabriel Jacobo wrote:
Quote:
2013/5/10 Martin Gerhardy
[snip]
Quote:
Quote:
  The glScissor calls are wrong, too? The rect is not given in x, y, w, h
to glScissor.
True, I didn’t look at the arguments at all, assuming they were
correct.  It seems they used the same coordinates as the d3d renderer.

Quote:
And I think it also doesn't translate the convention from SDL coordinates
(origin at top, left) to OpenGL (origin at bottom,left).
I fixed that in my latest patch[1].

[1] http://linkmauve.fr/files/fix-7141.patch

sorry, but this is still not correct.

you have to do:

int lowerLeft = window->height - rect.y - rect.height;
glScissor(rect.x, lowerLeft, rect.width, rect.height);

I hope there is no typo in this... and I hope I'm right with this ;)

Greetings
Martin


Yes, you are absolutely right!

--
Gabriel.
Link error with programs compiled without OpenGL
Martin Gerhardy
Guest
Post Posted: Sat May 11, 2013 6:56 am
Am 10.05.2013 21:15, schrieb Gabriel Jacobo:

Quote:



2013/5/10 Martin Gerhardy
Quote:
Am 10.05.2013 15:13, schrieb Emmanuel Gil Peyrot:
Quote:
On Fri, May 10, 2013 at 09:51:47AM -0300, Gabriel Jacobo wrote:
Quote:
2013/5/10 Martin Gerhardy
[snip]
Quote:
Quote:
The glScissor calls are wrong, too? The rect is not given in x, y, w, h
to glScissor.
True, I didn’t look at the arguments at all, assuming they were
correct. It seems they used the same coordinates as the d3d renderer.

Quote:
And I think it also doesn't translate the convention from SDL coordinates
(origin at top, left) to OpenGL (origin at bottom,left).
I fixed that in my latest patch[1].

[1] http://linkmauve.fr/files/fix-7141.patch

sorry, but this is still not correct.

you have to do:

int lowerLeft = window->height - rect.y - rect.height;
glScissor(rect.x, lowerLeft, rect.width, rect.height);

I hope there is no typo in this... and I hope I'm right with this ;)

Greetings
Martin


Yes, you are absolutely right!

--
Gabriel.



http://bugzilla.libsdl.org/show_bug.cgi?id=1844

here is the patch for the issue.

Regards
Martin