4 **apitrace** consists of a set of tools to:
6 * trace OpenGL, OpenGL ES, D3D9, D3D8, D3D7, and DDRAW APIs calls to a file;
8 * retrace OpenGL and OpenGL ES calls from a file;
10 * inspect OpenGL state at any call while retracing;
12 * visualize and edit trace files.
22 Run the application you want to trace as
24 apitrace trace /path/to/application [args...]
26 and it will generate a trace named `application.trace` in the current
27 directory. You can specify the written trace filename by setting the
28 `TRACE_FILE` environment variable before running.
32 apitrace dump --color application.trace
34 Replay an OpenGL trace with
36 glretrace application.trace
38 Pass the `-sb` option to use a single buffered visual. Pass `--help` to
39 glretrace for more options.
43 qapitrace application.trace
49 * Copy `opengl32.dll`, `d3d8.dll`, or `d3d9.dll` from build/wrappers directory
50 to the directory with the application you want to trace.
52 * Run the application.
56 \path\to\apitrace dump application.trace
58 * Replay the trace with
60 \path\to\glretrace application.trace
63 Advanced command line usage
64 ===========================
72 Run the application you want to trace as
74 LD_PRELOAD=/path/to/apitrace/wrappers/glxtrace.so /path/to/application
76 and it will generate a trace named `application.trace` in the current
77 directory. You can specify the written trace filename by setting the
78 `TRACE_FILE` environment variable before running.
80 The `LD_PRELOAD` mechanism should work with most applications. There are some
81 applications, e.g., Unigine Heaven, which global function pointers with the
82 same name as GL entrypoints, living in a shared object that wasn't linked with
83 `-Bsymbolic` flag, so relocations to those globals function pointers get
84 overwritten with the address to our wrapper library, and the application will
85 segfault when trying to write to them. For these applications it is possible
86 to trace by using `glxtrace.so` as an ordinary `libGL.so` and injecting into
89 ln -s glxtrace.so wrappers/libGL.so
90 ln -s glxtrace.so wrappers/libGL.so.1
91 ln -s glxtrace.so wrappers/libGL.so.1.2
92 export LD_LIBRARY_PATH=/path/to/apitrace/wrappers:$LD_LIBRARY_PATH
93 export TRACE_LIBGL=/path/to/real/libGL.so.1
96 See the `ld.so` man page for more information about `LD_PRELOAD` and
97 `LD_LIBRARY_PATH` environment flags.
99 To trace the application inside gdb, invoke gdb as:
101 gdb --ex 'set exec-wrapper env LD_PRELOAD=/path/to/glxtrace.so' --args /path/to/application
105 Run the application you want to trace as
107 DYLD_LIBRARY_PATH=/path/to/apitrace/wrappers /path/to/application
109 Note that although Mac OS X has an `LD_PRELOAD` equivalent,
110 `DYLD_INSERT_LIBRARIES`, it is mostly useless because it only works with
111 `DYLD_FORCE_FLAT_NAMESPACE=1` which breaks most applications. See the `dyld` man
112 page for more details about these environment flags.
115 Emitting annotations to the trace from GL applications
116 ------------------------------------------------------
118 You can emit string and frame annotations through the
119 [`GL_GREMEDY_string_marker`](http://www.opengl.org/registry/specs/GREMEDY/string_marker.txt)
121 [`GL_GREMEDY_frame_terminator`](http://www.opengl.org/registry/specs/GREMEDY/frame_terminator.txt)
124 **apitrace** will advertise and intercept these GL extensions independently of
125 the GL implementation. So all you have to do is to use these extensions when
128 For example, if you use [GLEW](http://glew.sourceforge.net/) to dynamically
129 detect and use GL extensions, you could easily accomplish this by doing:
133 if (GLEW_GREMEDY_string_marker) {
134 glStringMarkerGREMEDY(0, __FUNCTION__ ": enter");
139 if (GLEW_GREMEDY_string_marker) {
140 glStringMarkerGREMEDY(0, __FUNCTION__ ": leave");
145 This has the added advantage of working equally well with gDEBugger.
148 Dump GL state at a particular call
149 ----------------------------------
151 You can get a dump of the bound GL state at call 12345 by doing:
153 glretrace -D 12345 application.trace > 12345.json
155 This is precisely the mechanism the GUI obtains its own state.
157 You can compare two state dumps by doing:
159 apitrace diff-state 12345.json 67890.json
162 Comparing two traces side by side
163 ---------------------------------
165 apitrace diff trace1.trace trace2.trace
167 This works only on Unices, and it will truncate the traces due to performance
171 Recording a video with FFmpeg
172 -----------------------------
174 You can make a video of the output by doing
176 glretrace -s - application.trace \
177 | ffmpeg -r 30 -f image2pipe -vcodec ppm -i pipe: -vcodec mpeg4 -y output.mp4
180 Advanced usage for OpenGL implementors
181 ======================================
183 There are several advanced usage examples meant for OpenGL implementors.
189 These are the steps to create a regression test-suite around **apitrace**:
193 * obtain reference snapshots, by doing:
195 mkdir /path/to/snapshots/
196 glretrace -s /path/to/reference/snapshots/ application.trace
200 * prune the snapshots which are not interesting
202 * to do a regression test, do:
204 glretrace -c /path/to/reference/snapshots/ application.trace
206 Alternatively, for a HTML summary, use `apitrace diff-images`:
208 glretrace -s /path/to/current/snapshots/ application.trace
209 apitrace diff-images --output summary.html /path/to/reference/snapshots/ /path/to/current/snapshots/
212 Automated git-bisection
213 -----------------------
215 With tracecheck.py it is possible to automate git bisect and pinpoint the
216 commit responsible for a regression.
218 Below is an example of using tracecheck.py to bisect a regression in the
219 Mesa-based Intel 965 driver. But the procedure could be applied to any GL
220 driver hosted on a git repository.
222 First, create a build script, named build-script.sh, containing:
226 export PATH=/usr/lib/ccache:$PATH
229 ./autogen.sh --disable-egl --disable-gallium --disable-glut --disable-glu --disable-glw --with-dri-drivers=i965
233 It is important that builds are both robust, and efficient. Due to broken
234 dependency discovery in Mesa's makefile system, it was necessary invoke `make
235 clean` in every iteration step. `ccache` should be installed to avoid
236 recompiling unchanged source files.
241 export LIBGL_DEBUG=verbose
242 export LD_LIBRARY_PATH=$PWD/lib
243 export LIBGL_DRIVERS_DIR=$PWD/lib
245 6491e9593d5cbc5644eb02593a2f562447efdcbb 71acbb54f49089b03d3498b6f88c1681d3f649ac \
246 -- src/mesa/drivers/dri/intel src/mesa/drivers/dri/i965/
247 git bisect run /path/to/tracecheck.py \
248 --precision-threshold 8.0 \
249 --build /path/to/build-script.sh \
250 --gl-renderer '.*Mesa.*Intel.*' \
251 --retrace=/path/to/glretrace \
252 -c /path/to/reference/snapshots/ \
253 topogun-1.06-orc-84k.trace
255 The trace-check.py script will skip automatically when there are build
258 The `--gl-renderer` option will also cause a commit to be skipped if the
259 `GL_RENDERER` is unexpected (e.g., when a software renderer or another GL
260 driver is unintentionally loaded due to missing symbol in the DRI driver, or
261 another runtime fault).
264 Side by side retracing
265 ----------------------
267 In order to determine which draw call a regression first manifests one could
268 generate snapshots for every draw call, using the `-S` option. That is, however,
269 very inefficient for big traces with many draw calls.
271 A faster approach is to run both the bad and a good GL driver side-by-side.
272 The latter can be either a previously known good build of the GL driver, or a
273 reference software renderer.
275 This can be achieved with retracediff.py script, which invokes glretrace with
276 different environments, allowing to choose the desired GL driver by
277 manipulating variables such as `LD_LIBRARY_PATH` or `LIBGL_DRIVERS_DIR`.
281 ./scripts/retracediff.py \
282 --ref-env LD_LIBRARY_PATH=/path/to/reference/GL/implementation \
284 --diff-prefix=/path/to/output/diffs \
294 * [Official mailing list](http://lists.freedesktop.org/mailman/listinfo/apitrace)
296 * [Zack Rusin's blog introducing the GUI](http://zrusin.blogspot.com/2011/04/apitrace.html)
298 * [Jose's Fonseca blog introducing the tool](http://jrfonseca.blogspot.com/2008/07/tracing-d3d-applications.html)
306 * [Proxy DLL](http://www.mikoweb.eu/index.php?node=21)
308 * [Intercept Calls to DirectX with a Proxy DLL](http://www.codeguru.com/cpp/g-m/directx/directx8/article.php/c11453/)
310 * [Direct3D 9 API Interceptor](http://graphics.stanford.edu/~mdfisher/D3D9Interceptor.html)
314 * [Microsoft PIX](http://msdn.microsoft.com/en-us/library/ee417062.aspx)
316 * [D3DSpy](http://doc.51windows.net/Directx9_SDK/?url=/directx9_sdk/graphics/programmingguide/TutorialsAndSamplesAndToolsAndTips/Tools/D3DSpy.htm): the predecessor of PIX
318 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)
326 * [BuGLe](http://www.opengl.org/sdk/tools/BuGLe/)
328 * [GLIntercept](http://code.google.com/p/glintercept/)
330 * [tracy](https://gitorious.org/tracy): OpenGL ES and OpenVG trace, retrace, and state inspection
334 * [gDEBugger](http://www.gremedy.com/products.php)
336 * [glslDevil](http://cumbia.informatik.uni-stuttgart.de/glsldevil/index.html)
338 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)