1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
GL4Java is prepared for XFree86 4.0 & OpenGL/DRI
================================================
Since GL4Java 2.7.1 and 2001 April 10,
everything works fine !
The following text is history ..
ctx := OpenGL rendering context
I have worked for the DRI compatibility of GL4Java.
GL4Java is an OpenGL language mapping for Java.
http://www.jausoft.com/gl4java
I used:
Linux version 2.3.99-pre6
DRI cvs source tree (check out at 30th April 2000)
GlideV3Dri-3.10-6
gcc version 2.95.2
glibc 2.1
Vodoo3 3dfx card
While working for the compatibility, I have found some
problems, which looks like bugs !
I really would love to see your comments about chapter 1-3,
thanxs a lot !
Some bugs in OpenGL/DRI should be fixed/worked around:
1.) 3dfx Bug: Missing library link for tdfx_dri.so
===================================================
This may happen for other drivers either.
/xc/lib/GL/mesa/src/drv/tdfx/Makefile line 1051:
old: REQUIREDLIBS = -lglide3x -lm
new: REQUIREDLIBS = -lglide3x -lm -L../../../.. -lGL
Now, the "ldd -r -v tdfx_dri.so" check does not complain
about missing symbols. And GL4Java is able to load this lib
via libGL.so ! The funny thing is, that the binary demos
does not complain about the missing links ...
3.) GLX/DRI Indirect Rendering mode
===================================
Within this mode, we have to use the GL4Java mode of
an own created window for the ctx !
Because without, we will not receive an double-buffered visual
for the allready existing java native window !
(But this work for DRI rendering mode)
So, the workaround is, that the flag/define
"GL4JAVA_FORCE_X11_OWN_WINDOW" is set.
So in DRI and indirect rendering mode,
an own native window is created !
4.) Java2 JVM must run in native threads mode
==============================================
The environment var "THREADS_FLAG=native" must be set !
Green threads does result in an exception ...
=====================================================================
FIXED:
======
2.) glxMakeCurrent(..) bug
==========================
Try the demo "glxdemo.c" (out of mesa/xdemos) !
If you modify the code, so that the function code of
"redraw" is encapsulated like this:
/**
dpy, win & ctx are globals ...
*/
Display *dpy=NULL;
GLXContext ctx=NULL;
Window win=0;
static void redraw( )
{
/**
* Make the ctx current to this thread
*/
glXMakeCurrent( dpy, win, ctx );
/*
... original code here
*/
/**
* Release the current thread's ctx,
* so that the ctx is usable for other threads ...
*/
glXMakeCurrent( dpy, None, NULL );
}
The very first "redraw" does work !
The upcoming calls just throwing the GL-Error messages:
"GL User Error: calling ; without a current context"
and the GL impl. are not called !
So - the call of "glXMakeCurrent( dpy, None, NULL )"
makes the glx management very unhappy :-(
A current workaround for GL4Java is the flag/define
"GLXDRIMAKECURRENTBUG" !
If this is set, the native implementation of the method
GLContext::gljFree() does not call "glXMakeCurrent( dpy, None, NULL )"
anymore ! So we do lost the thread safety !
> In xc/xc/lib/GL/mesa/src/drv/tdfx/tdfx_xmesa.c in
> the XMesaMakeCurrent()
> function, look for this line (should be line 228):
>
> if (c==gCC) return GL_TRUE;
>
> Remove it.
1st May 2000
Sven Goethel
http://www.jausoft.com
mailto:gl4java@jausoft.com
mailto:sgoethel@jausoft.com
|
