*misc

1 files changed, 15 insertions, 0 deletions

diff --git a/src/math/mat.c b/src/math/mat.c
index 84a5a41..f889697 100644
--- a/src/math/mat.c
+++ b/src/math/mat.c
@@ -9,6 +9,7 @@
 
 static Mat4 sharedMat;
 static Mat4 sharedMat2;
+static Vec3 sharedVec3;
 static Vec4 sharedVec4;
 
 Mat4 mat4identity = {
@@ -333,6 +334,20 @@ void mat4_applytovec4(Mat4* mat, Vec4* v, Vec4* out) {
 	out->w = mat->e30 * v->x + mat->e31 * v->y + mat->e32 * v->z + mat->e33 * v->w;
 }
 
+/*
+** mat3 apply to vec3
+*/
+void mat4_applytovec3(Mat4* mat, Vec3* v, Vec3* out) {
+	ssr_assert(mat && v && out);
+	if (v == out) {
+		sharedVec3 = *v;
+		v = &sharedVec3;
+	}
+	out->x = mat->e00 * v->x + mat->e01 * v->y + mat->e02 * v->z;
+	out->y = mat->e10 * v->x + mat->e11 * v->y + mat->e12 * v->z;
+	out->z = mat->e20 * v->x + mat->e21 * v->y + mat->e22 * v->z;
+}
+
 #define trans(r, c) out->e##r##c = m->e##c##r
 
 void mat4_transpose(Mat4* m, Mat4* out) {