[Bf-blender-cvs] [9bea012] blender2.8: specialize mat3 multiply routines

[Mike Erwin]

Commit: 9bea012b8ca081a1bf696bf0af354ac327334354
Author: Mike Erwin
Date:   Sun Sep 25 18:48:11 2016 +0200
Branches: blender2.8
https://developer.blender.org/rB9bea012b8ca081a1bf696bf0af354ac327334354

specialize mat3 multiply routines

Same as 5c6baf1ee9754e39392926cd077bb2097baf39b9 but for 3x3 matrices.

===================================================================

M	source/blender/blenlib/BLI_math_matrix.h
M	source/blender/blenlib/intern/math_matrix.c

===================================================================

diff --git a/source/blender/blenlib/BLI_math_matrix.h b/source/blender/blenlib/BLI_math_matrix.h
index a5868e0..73effb3 100644
--- a/source/blender/blenlib/BLI_math_matrix.h
+++ b/source/blender/blenlib/BLI_math_matrix.h
@@ -72,10 +72,17 @@ void mul_m4_m4m3(float R[4][4], const float A[4][4], const float B[3][3]);
 void mul_m4_m4m4(float R[4][4], const float A[4][4], const float B[4][4]);
 void mul_m3_m3m4(float R[3][3], const float A[4][4], const float B[3][3]);
 
-/* special matrix multiplies */
-void mul_m4_m4m4_uniq(float R[4][4], const float A[4][4], const float B[4][4]); /* R <-- AB, R is neither A nor B */
-void mul_m4_m4_pre(float R[4][4], const float A[4][4]); /* R <-- AR */
-void mul_m4_m4_post(float R[4][4], const float B[4][4]); /* R <-- RB */
+/* special matrix multiplies
+ * uniq: R <-- AB, R is neither A nor B
+ * pre:  R <-- AR
+ * post: R <-- RB
+ */
+void mul_m3_m3m3_uniq(float R[3][3], const float A[3][3], const float B[3][3]);
+void mul_m3_m3_pre(float R[3][3], const float A[3][3]);
+void mul_m3_m3_post(float R[3][3], const float B[3][3]);
+void mul_m4_m4m4_uniq(float R[4][4], const float A[4][4], const float B[4][4]);
+void mul_m4_m4_pre(float R[4][4], const float A[4][4]);
+void mul_m4_m4_post(float R[4][4], const float B[4][4]);
 
 /* mul_m3_series */
 void _va_mul_m3_series_3(float R[3][3], float M1[3][3], float M2[3][3]) ATTR_NONNULL();
diff --git a/source/blender/blenlib/intern/math_matrix.c b/source/blender/blenlib/intern/math_matrix.c
index b22061b..2088ec8 100644
--- a/source/blender/blenlib/intern/math_matrix.c
+++ b/source/blender/blenlib/intern/math_matrix.c
@@ -229,27 +229,47 @@ void mul_m4_m4_post(float R[4][4], const float B[4][4])
 	mul_m4_m4m4_uniq(R, A, B);
 }
 
-void mul_m3_m3m3(float m1[3][3], const float m3_[3][3], const float m2_[3][3])
+void mul_m3_m3m3(float R[3][3], const float A[3][3], const float B[3][3])
 {
-	float m2[3][3], m3[3][3];
+	if (A == R)
+		mul_m3_m3_post(R, B);
+	else if (B == R)
+		mul_m3_m3_pre(R, A);
+	else
+		mul_m3_m3m3_uniq(R, A, B);
+}
 
-	/* copy so it works when m1 is the same pointer as m2 or m3 */
-	/* TODO: avoid copying when matrices are different */
-	copy_m3_m3(m2, m2_);
-	copy_m3_m3(m3, m3_);
+void mul_m3_m3_pre(float R[3][3], const float A[3][3])
+{
+	BLI_assert(A != R);
+	float B[3][3];
+	copy_m3_m3(B, R);
+	mul_m3_m3m3_uniq(R, A, B);
+}
 
-	/* m1[i][j] = m2[i][k] * m3[k][j], args are flipped!  */
-	m1[0][0] = m2[0][0] * m3[0][0] + m2[0][1] * m3[1][0] + m2[0][2] * m3[2][0];
-	m1[0][1] = m2[0][0] * m3[0][1] + m2[0][1] * m3[1][1] + m2[0][2] * m3[2][1];
-	m1[0][2] = m2[0][0] * m3[0][2] + m2[0][1] * m3[1][2] + m2[0][2] * m3[2][2];
+void mul_m3_m3_post(float R[3][3], const float B[3][3])
+{
+	BLI_assert(B != R);
+	float A[3][3];
+	copy_m3_m3(A, R);
+	mul_m3_m3m3_uniq(R, A, B);
+}
 
-	m1[1][0] = m2[1][0] * m3[0][0] + m2[1][1] * m3[1][0] + m2[1][2] * m3[2][0];
-	m1[1][1] = m2[1][0] * m3[0][1] + m2[1][1] * m3[1][1] + m2[1][2] * m3[2][1];
-	m1[1][2] = m2[1][0] * m3[0][2] + m2[1][1] * m3[1][2] + m2[1][2] * m3[2][2];
+void mul_m3_m3m3_uniq(float R[3][3], const float A[3][3], const float B[3][3])
+{
+	BLI_assert(R != A && R != B);
 
-	m1[2][0] = m2[2][0] * m3[0][0] + m2[2][1] * m3[1][0] + m2[2][2] * m3[2][0];
-	m1[2][1] = m2[2][0] * m3[0][1] + m2[2][1] * m3[1][1] + m2[2][2] * m3[2][1];
-	m1[2][2] = m2[2][0] * m3[0][2] + m2[2][1] * m3[1][2] + m2[2][2] * m3[2][2];
+	R[0][0] = B[0][0] * A[0][0] + B[0][1] * A[1][0] + B[0][2] * A[2][0];
+	R[0][1] = B[0][0] * A[0][1] + B[0][1] * A[1][1] + B[0][2] * A[2][1];
+	R[0][2] = B[0][0] * A[0][2] + B[0][1] * A[1][2] + B[0][2] * A[2][2];
+
+	R[1][0] = B[1][0] * A[0][0] + B[1][1] * A[1][0] + B[1][2] * A[2][0];
+	R[1][1] = B[1][0] * A[0][1] + B[1][1] * A[1][1] + B[1][2] * A[2][1];
+	R[1][2] = B[1][0] * A[0][2] + B[1][1] * A[1][2] + B[1][2] * A[2][2];
+
+	R[2][0] = B[2][0] * A[0][0] + B[2][1] * A[1][0] + B[2][2] * A[2][0];
+	R[2][1] = B[2][0] * A[0][1] + B[2][1] * A[1][1] + B[2][2] * A[2][1];
+	R[2][2] = B[2][0] * A[0][2] + B[2][1] * A[1][2] + B[2][2] * A[2][2];
 }
 
 void mul_m4_m4m3(float m1[4][4], const float m3_[4][4], const float m2_[3][3])
@@ -1651,7 +1671,7 @@ void translate_m4(float mat[4][4], float Tx, float Ty, float Tz)
 	mat[3][2] += (Tx * mat[0][2] + Ty * mat[1][2] + Tz * mat[2][2]);
 }
 
-/* TODO: enum for axis */
+/* TODO: enum for axis? */
 void rotate_m4(float mat[4][4], const char axis, const float angle)
 {
 	int col;