4 **apitrace** consists of a set of tools to:
6 * trace OpenGL, D3D9, D3D8, D3D7, and DDRAW APIs calls to a file;
8 * retrace OpenGL 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 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 /path/to/apitrace dump --color application.trace | less -R
36 /path/to/glretrace application.trace
38 Pass the `-sb` option to use a single buffered visual. Pass `--help` to
39 glretrace for more options.
43 /path/to/qapitrace application.trace
45 Special notes on "apitrace trace" for Linux
46 -------------------------------------------
47 The "apitrace trace" command uses the `LD_PRELOAD` mechanism which
48 should work with most applications. There are some applications,
49 e.g., Unigine Heaven, which global function pointers with the same
50 name as GL entrypoints, living in a shared object that wasn't linked
51 with `-Bsymbolic` flag, so relocations to those globals function
52 pointers get overwritten with the address to our wrapper library, and
53 the application will segfault when trying to write to them.
55 For these applications it is possible to trace by using `glxtrace.so`
56 as an ordinary `libGL.so` and injecting into `LD_LIBRARY_PATH`:
58 ln -s glxtrace.so libGL.so
59 ln -s glxtrace.so libGL.so.1
60 ln -s glxtrace.so libGL.so.1.2
61 export LD_LIBRARY_PATH=/path/to/directory/where/glxtrace/is:$LD_LIBRARY_PATH
62 export TRACE_LIBGL=/path/to/real/libGL.so.1
65 See the `ld.so` man page for more information about `LD_PRELOAD` and
66 `LD_LIBRARY_PATH` environment flags.
69 Special notes on "apitrace trace" for Mac OS X
70 ----------------------------------------------
71 On Mac OS X the "apitrace trace" command sets the following
72 environment variable before executing the program:
74 DYLD_LIBRARY_PATH=/path/to/apitrace/wrappers
76 Note that although Mac OS X has an `LD_PRELOAD` equivalent,
77 `DYLD_INSERT_LIBRARIES`, it is mostly useless because it only works
78 with `DYLD_FORCE_FLAT_NAMESPACE=1` which breaks most applications.
79 See the `dyld` man page for more details about these environment
86 * Copy `opengl32.dll`, `d3d8.dll`, or `d3d9.dll` from build/wrappers directory
87 to the directory with the application you want to trace.
89 * Run the application.
93 \path\to\apitrace dump application.trace
95 * Replay the trace with
97 \path\to\glretrace application.trace
100 Advanced command line usage
101 ===========================
104 Emitting annotations to the trace from GL applications
105 ------------------------------------------------------
107 You can emit string and frame annotations through the
108 [`GL_GREMEDY_string_marker`](http://www.opengl.org/registry/specs/GREMEDY/string_marker.txt)
110 [`GL_GREMEDY_frame_terminator`](http://www.opengl.org/registry/specs/GREMEDY/frame_terminator.txt)
113 **apitrace** will advertise and intercept these GL extensions independently of
114 the GL implementation. So all you have to do is to use these extensions when
117 For example, if you use [GLEW](http://glew.sourceforge.net/) to dynamically
118 detect and use GL extensions, you could easily accomplish this by doing:
122 if (GLEW_GREMEDY_string_marker) {
123 glStringMarkerGREMEDY(0, __FUNCTION__ ": enter");
128 if (GLEW_GREMEDY_string_marker) {
129 glStringMarkerGREMEDY(0, __FUNCTION__ ": leave");
134 This has the added advantage of working equally well with gDEBugger.
137 Dump GL state at a particular call
138 ----------------------------------
140 You can get a dump of the bound GL state at call 12345 by doing:
142 /path/to/glretrace -D 12345 application.trace > 12345.json
144 This is precisely the mechanism the GUI obtains its own state.
146 You can compare two state dumps with the jsondiff.py script:
148 ./scripts/jsondiff.py 12345.json 67890.json
151 Comparing two traces side by side
152 ---------------------------------
154 ./scripts/tracediff.sh trace1.trace trace2.trace
156 This works only on Unices, and it will truncate the traces due to performance
160 Recording a video with FFmpeg
161 -----------------------------
163 You can make a video of the output by doing
165 /path/to/glretrace -s - application.trace \
166 | ffmpeg -r 30 -f image2pipe -vcodec ppm -i pipe: -vcodec mpeg4 -y output.mp4
169 Advanced usage for OpenGL implementors
170 ======================================
172 There are several advanced usage examples meant for OpenGL implementors.
178 These are the steps to create a regression test-suite around **apitrace**:
182 * obtain reference snapshots, by doing:
184 mkdir /path/to/snapshots/
185 /path/to/glretrace -s /path/to/reference/snapshots/ application.trace
189 * prune the snapshots which are not interesting
191 * to do a regression test, do:
193 /path/to/glretrace -c /path/to/reference/snapshots/ application.trace
195 Alternatively, for a HTML summary, use the snapdiff script:
197 /path/to/glretrace -s /path/to/current/snapshots/ application.trace
198 ./scripts/snapdiff.py --output summary.html /path/to/reference/snapshots/ /path/to/current/snapshots/
201 Automated git-bisection
202 -----------------------
204 With tracecheck.py it is possible to automate git bisect and pinpoint the
205 commit responsible for a regression.
207 Below is an example of using tracecheck.py to bisect a regression in the
208 Mesa-based Intel 965 driver. But the procedure could be applied to any GL
209 driver hosted on a git repository.
211 First, create a build script, named build-script.sh, containing:
215 export PATH=/usr/lib/ccache:$PATH
218 ./autogen.sh --disable-egl --disable-gallium --disable-glut --disable-glu --disable-glw --with-dri-drivers=i965
222 It is important that builds are both robust, and efficient. Due to broken
223 dependency discovery in Mesa's makefile system, it was necessary invoke `make
224 clean` in every iteration step. `ccache` should be installed to avoid
225 recompiling unchanged source files.
230 export LIBGL_DEBUG=verbose
231 export LD_LIBRARY_PATH=$PWD/lib
232 export LIBGL_DRIVERS_DIR=$PWD/lib
234 6491e9593d5cbc5644eb02593a2f562447efdcbb 71acbb54f49089b03d3498b6f88c1681d3f649ac \
235 -- src/mesa/drivers/dri/intel src/mesa/drivers/dri/i965/
236 git bisect run /path/to/tracecheck.py \
237 --precision-threshold 8.0 \
238 --build /path/to/build-script.sh \
239 --gl-renderer '.*Mesa.*Intel.*' \
240 --retrace=/path/to/glretrace \
241 -c /path/to/reference/snapshots/ \
242 topogun-1.06-orc-84k.trace
244 The trace-check.py script will skip automatically when there are build
247 The `--gl-renderer` option will also cause a commit to be skipped if the
248 `GL_RENDERER` is unexpected (e.g., when a software renderer or another GL
249 driver is unintentionally loaded due to missing symbol in the DRI driver, or
250 another runtime fault).
253 Side by side retracing
254 ----------------------
256 In order to determine which draw call a regression first manifests one could
257 generate snapshots for every draw call, using the `-S` option. That is, however,
258 very inefficient for big traces with many draw calls.
260 A faster approach is to run both the bad and a good GL driver side-by-side.
261 The latter can be either a previously known good build of the GL driver, or a
262 reference software renderer.
264 This can be achieved with retracediff.py script, which invokes glretrace with
265 different environments, allowing to choose the desired GL driver by
266 manipulating variables such as `LD_LIBRARY_PATH` or `LIBGL_DRIVERS_DIR`.
270 ./scripts/retracediff.py \
271 --ref-env LD_LIBRARY_PATH=/path/to/reference/GL/implementation \
273 --diff-prefix=/path/to/output/diffs \
283 * [Official mailing list](http://lists.freedesktop.org/mailman/listinfo/apitrace)
285 * [Zack Rusin's blog introducing the GUI](http://zrusin.blogspot.com/2011/04/apitrace.html)
287 * [Jose's Fonseca blog introducing the tool](http://jrfonseca.blogspot.com/2008/07/tracing-d3d-applications.html)
295 * [Proxy DLL](http://www.mikoweb.eu/index.php?node=21)
297 * [Intercept Calls to DirectX with a Proxy DLL](http://www.codeguru.com/cpp/g-m/directx/directx8/article.php/c11453/)
299 * [Direct3D 9 API Interceptor](http://graphics.stanford.edu/~mdfisher/D3D9Interceptor.html)
303 * [Microsoft PIX](http://msdn.microsoft.com/en-us/library/ee417062.aspx)
305 * [D3DSpy](http://doc.51windows.net/Directx9_SDK/?url=/directx9_sdk/graphics/programmingguide/TutorialsAndSamplesAndToolsAndTips/Tools/D3DSpy.htm): the predecessor of PIX
307 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)
315 * [BuGLe](http://www.opengl.org/sdk/tools/BuGLe/)
317 * [GLIntercept](http://code.google.com/p/glintercept/)
319 * [tracy](https://gitorious.org/tracy): OpenGL ES and OpenVG trace, retrace, and state inspection
323 * [gDEBugger](http://www.gremedy.com/products.php)
325 * [glslDevil](http://cumbia.informatik.uni-stuttgart.de/glsldevil/index.html)
327 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)