BLI_math_matrix: add invert_m4_m4_safe_ortho (m3 version too)

Unlike invert_m4_m4_safe, this calculates zeroed axes.
Useful when we need to use the inverse of an objects matrix,
keeping the valid axis, only filling in the zeroed ones.

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_math_matrix.h b/source/blender/blenlib/BLI_math_matrix.h
index a00fdaa0ae9..09f2d5a7cdc 100644
--- a/source/blender/blenlib/BLI_math_matrix.h
+++ b/source/blender/blenlib/BLI_math_matrix.h
@@ -299,6 +299,9 @@ bool has_zero_axis_m4(const float matrix[4][4]);
 
 void invert_m4_m4_safe(float Ainv[4][4], const float A[4][4]);
 
+void invert_m3_m3_safe_ortho(float Ainv[3][3], const float A[3][3]);
+void invert_m4_m4_safe_ortho(float Ainv[4][4], const float A[4][4]);
+
 /****************************** Transformations ******************************/
 
 void scale_m3_fl(float R[3][3], float scale);