d23125e14c
In the previous commit, we simply accomodated for alpha errors when compressing single color partitions. In fact, the issue was a bit more greivous: we weren't computing the proper error term at all! This fixed that function so that we emphasize the error metrics induced by *squaring* the error in each channel and then returning that as a measurement of the acceptability of using a single color compression for that partition. |
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BPTCEncoder | ||
CLTool | ||
Core | ||
IO | ||
QtGUI | ||
Windows@326dfccf36 | ||
.gitmodules | ||
CMakeLists.txt | ||
README.md |
FasTC
A Fast Texture Compressor for the BPTC (a.k.a. BC7) format. This compressor supports multi-threading through Boost's threading API and runs on Windows, OS X, and Linux
Requirements:
CMake (2.8.8)
Boost (tested with v1.50 and higher)
libpng (1.5.13)
zlib (1.2.5)
Installation:
FasTC uses CMake to generate build files. The best way to do so is to create a separate build directory for compilation:
mkdir FasTC
cd FasTC
git clone git@github.com:Mokosha/FasTC.git src
mkdir build
cd build
cmake ../src -DCMAKE_BUILD_TYPE=Release
make
Once you do this you will be able to run some examples.
Using Visual Studio on Windows
Due to the C/C++ runtime requirements in Visual Studio, you must have a compiled version of each library that you wish to link to. In order to save time, I have uploaded various versions of Boost, libpng, and zlib to a submodule in the source directory. Before running the steps above, make sure to instantiate the submodule in git:
cd FasTC/src
git submodule init
git submodule update
This will download all of the Release versions of the necessary libraries (which means there will be linker errors during the build process). I have compiled versions for Visual Studio 2008, 2010, and 2012.
Testing:
Once the compressor is built, you may test it against any images you wish as long as their dimensions are multiples of four and they are in the png file format. If you'd like to convert from one format to another, I suggest taking a look at ImageMagick
The quickest test will be to simply run the compressor on a PNG image:
cd FasTC/build
make
CLTool/tc path/to/image.png
There are various run-time options available:
-t
: Specifies the number of threads to use for compression. The default is one.-l
: Save an output log of various statistics during compression. This is mostly only useful for debugging.-q <num>
: Usenum
steps of simulated annealing during each endpoint compression. Default is 50-n <num>
: Performnum
compressions in a row. This is good for testing metrics.-a
: Use a parallel algorithm that uses Fetch-And-Add and Test-And-Set to perform mutual exclusion and avoid synchronization primitives. This algorithm is very useful when compressing a list of textures. Cannot be used with the-j
option.-j <num>
: This specifies the number of 4x4 blocks that the compressor will crunch per thread. The default is to split the image up so that each thread compresses an equal share of the image. However, for many images, certain blocks compress faster than others, and you might want a more fine grained control over how to switch between compressing different blocks.
As an example, if I wanted to test compressing a texture using no simulated annealing, 4 threads, and 32 blocks per job, I would invoke the following command:
CLTool/tc -q 0 -t 4 -j 32 path/to/image.png
If I wanted to compress a texture with the default amount of simulated annealing 100 times using the parallel algorithm with atomic synchronization primitives, I would invoke the following command:
CLTool/tc -n 100 -a path/to/image.png