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.
18 Run the application you want to trace as
20 apitrace trace --api API /path/to/application [args...]
22 and it will generate a trace named `application.trace` in the current
23 directory. You can specify the written trace filename by passing the
24 `--output` command line option.
26 Problems while tracing (e.g, if the application uses calls/parameters
27 unsupported by apitrace) will be reported via stderr output on Unices. On
28 Windows you'll need to run
29 [DebugView](http://technet.microsoft.com/en-us/sysinternals/bb896647) to view
34 apitrace dump application.trace
36 Replay an OpenGL trace with
38 glretrace application.trace
40 Pass the `-sb` option to use a single buffered visual. Pass `--help` to
41 glretrace for more options.
45 qapitrace application.trace
48 Advanced command line usage
49 ===========================
55 Several tools take `CALLSET` arguments, e.g:
57 apitrace dump --calls CALLSET foo.trace
58 glretrace -S CALLSET foo.trace
60 The call syntax is very flexible. Here are a few examples:
64 * `1,2,4,5` set of calls
66 * `"1 2 4 5"` set of calls (commas are optional and can be replaced with whitespace)
68 * `1-100/2` calls 1, 3, 5, ..., 99
70 * `1-1000/draw` all draw calls between 1 and 1000
72 * `1-1000/fbo` all fbo changes between calls 1 and 1000
74 * `frame` all calls at end of frames
76 * `@foo.txt` read call numbers from `foo.txt`, using the same syntax as above
85 Run the application you want to trace as
87 LD_PRELOAD=/path/to/apitrace/wrappers/glxtrace.so /path/to/application
89 and it will generate a trace named `application.trace` in the current
90 directory. You can specify the written trace filename by setting the
91 `TRACE_FILE` environment variable before running.
93 The `LD_PRELOAD` mechanism should work with most applications. There are some
94 applications, e.g., Unigine Heaven, which global function pointers with the
95 same name as GL entrypoints, living in a shared object that wasn't linked with
96 `-Bsymbolic` flag, so relocations to those globals function pointers get
97 overwritten with the address to our wrapper library, and the application will
98 segfault when trying to write to them. For these applications it is possible
99 to trace by using `glxtrace.so` as an ordinary `libGL.so` and injecting into
102 ln -s glxtrace.so wrappers/libGL.so
103 ln -s glxtrace.so wrappers/libGL.so.1
104 ln -s glxtrace.so wrappers/libGL.so.1.2
105 export LD_LIBRARY_PATH=/path/to/apitrace/wrappers:$LD_LIBRARY_PATH
106 export TRACE_LIBGL=/path/to/real/libGL.so.1
109 See the `ld.so` man page for more information about `LD_PRELOAD` and
110 `LD_LIBRARY_PATH` environment flags.
112 To trace the application inside gdb, invoke gdb as:
114 gdb --ex 'set exec-wrapper env LD_PRELOAD=/path/to/glxtrace.so' --args /path/to/application
118 Run the application you want to trace as
120 DYLD_LIBRARY_PATH=/path/to/apitrace/wrappers /path/to/application
122 Note that although Mac OS X has an `LD_PRELOAD` equivalent,
123 `DYLD_INSERT_LIBRARIES`, it is mostly useless because it only works with
124 `DYLD_FORCE_FLAT_NAMESPACE=1` which breaks most applications. See the `dyld` man
125 page for more details about these environment flags.
129 Copy `opengl32.dll`, `d3d8.dll`, or `d3d9.dll` from the wrappers directory
130 to the directory with the application you want to trace. Then run the
133 You can specify the written trace filename by setting the `TRACE_FILE`
134 environment variable before running.
137 Emitting annotations to the trace
138 ---------------------------------
140 From OpenGL applications you can embed annotations in the trace file through the
141 [`GL_GREMEDY_string_marker`](http://www.opengl.org/registry/specs/GREMEDY/string_marker.txt)
143 [`GL_GREMEDY_frame_terminator`](http://www.opengl.org/registry/specs/GREMEDY/frame_terminator.txt)
146 **apitrace** will advertise and intercept these GL extensions independently of
147 the GL implementation. So all you have to do is to use these extensions when
150 For example, if you use [GLEW](http://glew.sourceforge.net/) to dynamically
151 detect and use GL extensions, you could easily accomplish this by doing:
155 if (GLEW_GREMEDY_string_marker) {
156 glStringMarkerGREMEDY(0, __FUNCTION__ ": enter");
161 if (GLEW_GREMEDY_string_marker) {
162 glStringMarkerGREMEDY(0, __FUNCTION__ ": leave");
167 This has the added advantage of working equally well with gDEBugger.
170 From OpenGL ES applications you can embed annotations in the trace file through the
171 [`GL_EXT_debug_marker`](http://www.khronos.org/registry/gles/extensions/EXT/EXT_debug_marker.txt)
175 For Direct3D applications you can follow the same procedure used for
176 [instrumenting an application for PIX](http://technet.microsoft.com/en-us/query/ee417250)
179 Dump GL state at a particular call
180 ----------------------------------
182 You can get a dump of the bound GL state at call 12345 by doing:
184 glretrace -D 12345 application.trace > 12345.json
186 This is precisely the mechanism the GUI obtains its own state.
188 You can compare two state dumps by doing:
190 apitrace diff-state 12345.json 67890.json
193 Comparing two traces side by side
194 ---------------------------------
196 apitrace diff trace1.trace trace2.trace
198 This works only on Unices, and it will truncate the traces due to performance
202 Recording a video with FFmpeg
203 -----------------------------
205 You can make a video of the output by doing
207 glretrace -s - application.trace \
208 | ffmpeg -r 30 -f image2pipe -vcodec ppm -i pipe: -vcodec mpeg4 -y output.mp4
214 You can make a smaller trace by doing:
216 apitrace trim --callset 100-1000 -o trimed.trace applicated.trace
218 If you need precise control over which calls to trim you can specify the
219 individual call numbers a plaintext file, as described in the 'Call sets'
223 Advanced usage for OpenGL implementors
224 ======================================
226 There are several advanced usage examples meant for OpenGL implementors.
232 These are the steps to create a regression test-suite around **apitrace**:
236 * obtain reference snapshots, by doing:
238 mkdir /path/to/snapshots/
239 glretrace -s /path/to/reference/snapshots/ application.trace
243 * prune the snapshots which are not interesting
245 * to do a regression test, do:
247 glretrace -c /path/to/reference/snapshots/ application.trace
249 Alternatively, for a HTML summary, use `apitrace diff-images`:
251 glretrace -s /path/to/current/snapshots/ application.trace
252 apitrace diff-images --output summary.html /path/to/reference/snapshots/ /path/to/current/snapshots/
255 Automated git-bisection
256 -----------------------
258 With tracecheck.py it is possible to automate git bisect and pinpoint the
259 commit responsible for a regression.
261 Below is an example of using tracecheck.py to bisect a regression in the
262 Mesa-based Intel 965 driver. But the procedure could be applied to any GL
263 driver hosted on a git repository.
265 First, create a build script, named build-script.sh, containing:
269 export PATH=/usr/lib/ccache:$PATH
272 ./autogen.sh --disable-egl --disable-gallium --disable-glut --disable-glu --disable-glw --with-dri-drivers=i965
276 It is important that builds are both robust, and efficient. Due to broken
277 dependency discovery in Mesa's makefile system, it was necessary invoke `make
278 clean` in every iteration step. `ccache` should be installed to avoid
279 recompiling unchanged source files.
284 export LIBGL_DEBUG=verbose
285 export LD_LIBRARY_PATH=$PWD/lib
286 export LIBGL_DRIVERS_DIR=$PWD/lib
288 6491e9593d5cbc5644eb02593a2f562447efdcbb 71acbb54f49089b03d3498b6f88c1681d3f649ac \
289 -- src/mesa/drivers/dri/intel src/mesa/drivers/dri/i965/
290 git bisect run /path/to/tracecheck.py \
291 --precision-threshold 8.0 \
292 --build /path/to/build-script.sh \
293 --gl-renderer '.*Mesa.*Intel.*' \
294 --retrace=/path/to/glretrace \
295 -c /path/to/reference/snapshots/ \
296 topogun-1.06-orc-84k.trace
298 The trace-check.py script will skip automatically when there are build
301 The `--gl-renderer` option will also cause a commit to be skipped if the
302 `GL_RENDERER` is unexpected (e.g., when a software renderer or another GL
303 driver is unintentionally loaded due to missing symbol in the DRI driver, or
304 another runtime fault).
307 Side by side retracing
308 ----------------------
310 In order to determine which draw call a regression first manifests one could
311 generate snapshots for every draw call, using the `-S` option. That is, however,
312 very inefficient for big traces with many draw calls.
314 A faster approach is to run both the bad and a good GL driver side-by-side.
315 The latter can be either a previously known good build of the GL driver, or a
316 reference software renderer.
318 This can be achieved with retracediff.py script, which invokes glretrace with
319 different environments, allowing to choose the desired GL driver by
320 manipulating variables such as `LD_LIBRARY_PATH` or `LIBGL_DRIVERS_DIR`.
324 ./scripts/retracediff.py \
325 --ref-env LD_LIBRARY_PATH=/path/to/reference/GL/implementation \
327 --diff-prefix=/path/to/output/diffs \
337 * [Official mailing list](http://lists.freedesktop.org/mailman/listinfo/apitrace)
339 * [Zack Rusin's blog introducing the GUI](http://zrusin.blogspot.com/2011/04/apitrace.html)
341 * [Jose's Fonseca blog introducing the tool](http://jrfonseca.blogspot.com/2008/07/tracing-d3d-applications.html)
349 * [Proxy DLL](http://www.mikoweb.eu/index.php?node=21)
351 * [Intercept Calls to DirectX with a Proxy DLL](http://www.codeguru.com/cpp/g-m/directx/directx8/article.php/c11453/)
353 * [Direct3D 9 API Interceptor](http://graphics.stanford.edu/~mdfisher/D3D9Interceptor.html)
357 * [Microsoft PIX](http://msdn.microsoft.com/en-us/library/ee417062.aspx)
359 * [D3DSpy](http://doc.51windows.net/Directx9_SDK/?url=/directx9_sdk/graphics/programmingguide/TutorialsAndSamplesAndToolsAndTips/Tools/D3DSpy.htm): the predecessor of PIX
361 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)
369 * [BuGLe](http://www.opengl.org/sdk/tools/BuGLe/)
371 * [GLIntercept](http://code.google.com/p/glintercept/)
373 * [tracy](https://gitorious.org/tracy): OpenGL ES and OpenVG trace, retrace, and state inspection
377 * [gDEBugger](http://www.gremedy.com/products.php)
379 * [glslDevil](http://cumbia.informatik.uni-stuttgart.de/glsldevil/index.html)
381 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)