EBSDLib is a C++ Library that can read EBSD Files from OEMs and perform basic EBSD processing such as orientation conversion and IPF Color generation. Another important aspect of the library is to be able to convert between the seven orientation representations that are typically used through out materials science and engineering domains.
The DREAM.3D project ( code repository and web site ) uses this library for all of the EBSD processing.
Please have a look at the unit tests for examples on using the various readers.
| From/To | Euler | Orientation Matrix | Axis Angle | Rodrigues | Quaternion | Homochoric | Cubochoric |
|---|---|---|---|---|---|---|---|
| Euler | - | X | X | X | X | a | ah |
| Orientation Matrix | X | -- | X | e | X | a | ah |
| Axis Angle | o | X | -- | X | X | X | h |
| Rodrigues | o | a | X | -- | a | X | h |
| Quaternion | X | X | X | X | -- | X | h |
| Homochoric | ao | a | X | a | a | -- | X |
| Cubochoric | hao | ha | h | ha | ha | X | -- |
LEGEND: X = Direct mathematical conversion between the representations lower case letters denote the conversion uses other more basic conversions. For example to go from Euler->Homochoric the conversion process calls the Euler->AxisAngle->OrientationMatrix->Homochoric functions.
In addition to the OrientationTransformation class there are also classes that represent the 11 Laue classes that allow a user to perform Laue class specific calculations including the generation of an IPF Color which is a prevalent visualization scheme within the EBSD community. Note that each vendor has slightly different algorithms and this library has selected to align with the AMETEK/EDAX output.
The folder Data/IPF_Legend has premade IPF Legends for all the Laue classes.
Please also note that by default EbsdLib organizes Quaternions as Vector-Scalar. If your quaternions are layed out as Scalar-Vector there is an extra argument to some functions that you can set to allow the orientation transformations to accept this layout.
EbsdLib is dependent on:
By convention this library uses Passive rotations
D Rowenhorst, A D Rollett, G S Rohrer, M Groeber, M Jackson, P J Konijnenberg and M De Graef et al 2015 Modelling Simul. Mater. Sci. Eng. 23 083501
DOI: https://doi.org/10.1088/0965-0393/23/8/083501
If you want to transform an Euler angle into a Quaternion the following works:
Quaternion<float> quat = OrientationTransformation::eu2qu(Orientation<float>(33.0f, 10.0f, 0.0f));If you have a lot of angles to transform the Orienation class can wrap a pointer instead at which point you can loop over the array of angles. There is also the OrientationConverter class that can mass transform from one representation into another.
Reading from an AMETEK .ang file is straightforward:
AngReader reader;
reader.setFileName(std::string("/path/to/ebsd_scan.ang"));
int32_t err = reader.readFile();
// All of the data from the .ang file is now in memory. You can access it through the pointers
size_t numElements = reader.getNumberOfElements();
float* ptr = reader.getPhi1Pointer();
// The reader will clean up the memory so either tell the reader to Not clean up the pointer or keep the reader in scope.