4 Before reporting, please skim through the known issues below.
6 Report any issues on [github](https://github.com/apitrace/apitrace/issues),
7 always including the following information:
9 * operating system name and version
11 * OpenGL/D3D driver name and version
17 These are issues that the developers are already aware of, but for which there
18 is no immediate plan to address them, because either:
20 * they stem from architectural limitations that are difficult to overcome
21 and/or time-consuming;
23 * they are corners cases that are thought to be of very little practical use;
25 * merely lack of time/opportunity.
27 That said, feel free to file an issue and/or send an email to the mailing list
30 * send an email to the mailing list if you want discuss the rationale, propose
31 your ideas on how to address it, or volunteer to work on it;
33 * file the issue in the issue tracker (or comment to it if it already exists)
34 if it is important for you and you would like to see it addressed sooner
41 * Fake calls may be emitted in the trace, in order to provide complete
42 information for retracing. The typical case is OpenGL vertex arrays in user
43 memory (as opposed to VBOs): where glXxxPointer calls will be deferred,
44 glInterleavedArrays will be decomposed, etc.
46 This should not affect the rendered output, but it may use different paths in
47 the OpenGL driver, exercising different paths and with different performance
50 There is no way to distinguish the fake calls from those actually
51 made by the application yet.
53 * Huge traces will be generated for applications that make extensive use of
54 immediate mode drawing (ie., glBegin/glEnd), use vertex/element arrays in
55 user memory, or generate a lot of dynamic vertex data per frame.
57 However, this should not be a problem for modern OpenGL applications that
58 make an efficient use of VBOs and vertex shaders.
60 * On MacOSX, the internal OpenGL calls done by GLU are not traced yet.
66 * Replaying can take substantially more CPU due to the overhead of reading the
69 However, the overhead should not be significant for modern 3D applications
70 that do efficient use of VBOs and vertex shaders. The communication between
71 CPU to GPU can easily be a bottleneck on the powerful discrete GPUs of
72 nowadays, and trace overhead tend to be propotional so it is not a
73 coincidence that applications that are optimized for modern GPUs will also be
74 traced and replayed efficiently.
76 * glretrace needs to infer window sizes from glViewport calls, because calls
77 that create/resize windows happen outside of OpenGL and are not traced.
78 Therefore window will be missing if the application relies on the default
79 viewport instead of explicitly invoking glViewport; or it will to too big if
80 the window is shrunk. Most apps call glViewport before rendering.
82 * OS specific OpenGL APIs (WGL, GLX, CGL, etc), are not retraced literally, but
83 instead partially emulated. This is by design, to allow traces to be
84 retraced on any OS, as the focus is on the OS-independent parts of OpenGL API.
86 * There is no guarantee that the same visual that was used on tracing will be
87 used for retracing OpenGL. Actually currently, glretrace will always choose
88 a standard 32bit RGBA, 24bit depth, 8bit alpha, double buffer visual. Unless
89 overridden on command line.
91 * Multi-threaded OpenGL is not yet supported.
93 * OpenGL context sharing is not fully respected -- all contexts are expected to
94 share state, and most likely there
100 * Not all types of arguments can be edited.
104 Proprietary/confidential applications
105 =====================================
107 Issues should be preferably filed on github to facilitate collaborative
108 development and for future reference.
110 Access to applications source code is not required -- binaries are sufficient.
112 If the bug happens with a proprietary application, and you don't want to
113 publicly release the application and/or any data collected from it, then
114 alternatively you can provide the necessary application and/or data via e-mail,
115 to *jose dot r dot fonseca at gmail dot com*.
117 If it is not technically/legally feasible for you to provide application and/or
118 data at all, then you must be either:
120 * develop and provide a test application, stripped-down of all
121 proprietary/confidential data, but that can reproduce the issue;
123 * be willing/able to do the investigation of the issue, namely to identify the
124 root cause of the issue (e.g., which OpenGL call is not properly handled and
125 why), using all necessary tools (such as debuggers).
127 Failure to do so will render the apitrace authors powerless to address the
134 github issue tracker doesn't support attachments.
136 Please attach long logs to https://gist.github.com/ and paste the URL into the
139 For big attachments, such as traces, please upload it temporarily to a web
140 server you control, or use a file upload service such as http://dropbox.com/
141 and paste the URL into the issue description.
143 Trace files are only slightly compressed (for performance reasons). You can
144 further reduce their size when attaching/uploading by compressing with
145 [XZ](http://tukaani.org/xz/) or [7-Zip](http://www.7-zip.org/).
151 For bugs that happen while tracing (e.g., crashes while tracing the
152 application, or incorrect traces) please:
154 * provide information on how to obtain the application;
156 * describe how you were using it when the issue happened.
159 Bugs on retracing/GUI
160 =====================
162 For bugs on retracing (e.g. crashes when retracing the application,
163 incorrect inconsistent rendering, or viewing with the GUI) please:
165 * provide the trace file;
167 * describe the results you got, and what results you were expecting.
170 Obtaining stack back-traces
171 ===========================
177 Please rebuild apitrace with debugging information, by passing
178 `-DCMAKE_BUILD_TYPE=Debug` to cmake.
180 To obtain a stack back-trace, run the application with gdb from a terminal:
182 $ gdb --args application arg1 arg2 ...
188 See also more detailed and Distro specific instructions:
190 * http://wiki.debian.org/HowToGetABacktrace
192 * https://wiki.ubuntu.com/Backtrace
194 * http://fedoraproject.org/wiki/StackTraces
196 * http://live.gnome.org/GettingTraces
204 * https://developer.mozilla.org/en/how_to_get_a_stacktrace_with_windbg