Math lib: add negate_m3, negate_m4

1 files changed, 18 insertions, 1 deletions

diff --git a/source/blender/blenlib/intern/math_matrix.c b/source/blender/blenlib/intern/math_matrix.c
index f375a5c01ed..7fc30e3112b 100644
--- a/source/blender/blenlib/intern/math_matrix.c
+++ b/source/blender/blenlib/intern/math_matrix.c
@@ -519,7 +519,6 @@ void mul_transposed_mat3_m4_v3(float mat[4][4], float vec[3])
 	vec[2] = x * mat[2][0] + y * mat[2][1] + mat[2][2] * vec[2];
 }
 
-
 void mul_m3_fl(float m[3][3], float f)
 {
 	int i, j;
@@ -547,6 +546,24 @@ void mul_mat3_m4_fl(float m[4][4], float f)
 			m[i][j] *= f;
 }
 
+void negate_m3(float m[4][4])
+{
+	int i, j;
+
+	for (i = 0; i < 3; i++)
+		for (j = 0; j < 3; j++)
+			m[i][j] *= -1.0f;
+}
+
+void negate_m4(float m[4][4])
+{
+	int i, j;
+
+	for (i = 0; i < 4; i++)
+		for (j = 0; j < 4; j++)
+			m[i][j] *= -1.0f;
+}
+
 void mul_m3_v3_double(float mat[3][3], double vec[3])
 {
 	double x, y;