1 files changed, 95 insertions, 0 deletions
diff --git a/libs/assimp/test/regression/README.txt b/libs/assimp/test/regression/README.txt
new file mode 100644
index 0000000..a37da92
--- /dev/null
+++ b/libs/assimp/test/regression/README.txt
@@ -0,0 +1,95 @@
+Asset Importer Lib Regression Test Suite
+========================================
+
+1) How does it work?
+---------------------------------------------------------------------------------
+run.py checks all model in the <root>/test/models* folders and compares the result
+against a regression database provided with assimp (db.zip). A few failures
+are totally fine (see sections 7+). You need to worry if a huge
+majority of all files in a particular format (or post-processing configuration)
+fails as this might be a sign of a recent regression in assimp's codebase or
+gross incompatibility with your system or compiler.
+
+2) What do I need?
+---------------------------------------------------------------------------------
+ - You need Python installed (2.7+, 3.x). On Windows, run the scripts using "py".
+ - You need to build the assimp command line tool (ASSIMP_BUILD_ASSIMP_TOOLS
+   CMake build flag). Both run.py and gen_db.py take the full path to the binary
+   as first command line parameter.
+
+3) How to add more test files?
+---------------------------------------------------------------------------------
+Use the following procedure:
+ - Verify the correctness of your assimp build - run the regression suite.
+   DO NOT continue if more tests fail than usual.
+ - Add your additional test files to <root>/test/models/<fileformat>, where
+   <fileformat> is the file type (typically the file extension).
+ - If you test file does not meet the BSD license requirements, add it to
+   <root>/test/models-nonbsd/<fileformat> so people know to be careful with it.
+ - Rebuild the regression database:
+   "gen_db.py <binary> -ixyz" where .xyz is the file extension of the new file.
+ - Run the regression suite again. There should be no new failures and the new
+   file should not be among the failures.
+ - Include the db.zip file with your Pull Request. Travis CI enforces a passing
+   regression suite (with offenders whitelisted as a last resort).
+
+4) I made a change/fix/patch to a loader, how to update the database?
+---------------------------------------------------------------------------------
+ - Rebuild the regression database using "gen_db.py <binary> -ixyz"
+   where .xyz is the file extension for which the loader was patched.
+ - Run the regression suite again. There should be no new failures and the new
+   file should not be among the failures.
+ - Include the db.zip file with your Pull Request. Travis CI enforces a passing
+   regression suite (with offenders whitelisted as a last resort).
+
+5) How to add my whole model repository to the database?
+---------------------------------------------------------------------------------
+
+Edit the reg_settings.py file and add the path to your repository to
+<<model_directories>>. Then, rebuild the database.
+
+6) So what is actually tested?
+---------------------------------------------------------------------------------
+The regression database includes mini dumps of the aiScene data structure, i.e.
+the scene hierarchy plus the sizes of all data arrays MUST match. Floating-point
+data buffers, such as vertex positions are handled less strictly: min, max and
+average values are stored with low precision. This takes hardware- or
+compiler-specific differences in floating-point computations into account.
+Generally, almost all significant regressions will be detected while the
+number of false positives is relatively low.
+
+7) The test suite fails, what do do?
+---------------------------------------------------------------------------------
+Get back to <root>/test/results and look at regression_suite_failures.txt.
+It contains a list of all files which failed the test. Failing dumps are copied to
+<root>/test/results/tmp. Both an EXPECTED and an ACTUAL file is produced per test.
+The output of "assimp cmpdump" is written to regressions_suite_output.txt. Grep
+for the file name in question and locate the log for the failed comparison. It
+contains a full trace of which scene elements have been compared before, which
+makes it reasonably easy to locate the offending field.
+
+8) fp:fast vs fp:precise fails the test suite (same for gcc equivalents)
+---------------------------------------------------------------------------------
+As mentioned above, floating-point inaccuracies between differently optimized
+builds are not considered regressions and all float comparisons done by the test
+suite involve an epsilon to accommodate. However compiler settings that allow
+compilers to perform non-IEEE754 compliant optimizations can cause arbitrary
+failures in the test suite. Even if the compiler is configured to be IEE754
+comformant, there is lots of code in assimp that leaves the compiler a choice
+and different compilers make different choices (for example the precision of
+float intermediaries is implementation-specified).
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+