1 files changed, 37 insertions, 0 deletions
diff --git a/src/extend/transform.c b/src/extend/transform.c
index e69de29..7724614 100644
--- a/src/extend/transform.c
+++ b/src/extend/transform.c
@@ -0,0 +1,37 @@
+#include "transform.h"
+
+void transform_getpositionandrotation(Transform* trans, Vec3* pos, Quat* rot) {
+	*pos = trans->localposition; 
+	*rot  = trans->localrotation;
+	Transform* cur = trans->parent;
+	while (cur) {	
+		/*按照srt的顺序计算pos*/
+		vec3_scale3(pos, &cur->localscale, pos);
+		quat_applytovec3(&cur->localrotation, pos, pos);
+		vec3_plus(pos, &cur->localposition, pos);
+		/*计算旋转*/
+		quat_multiply(&cur->localrotation, rot, rot);
+
+		cur = cur->parent;
+	}
+}
+
+void transform_getinvmatrixnoscale(Transform* trans, Mat4* worldToLocal) {
+	Vec3 pos; Quat rot;
+	transform_getpositionandrotation(trans, &pos, &rot);
+	quat_invert(&rot, &rot);
+	/*(TR)^-1 = R^-1T^-1*/
+	quat_tomat4(&rot, worldToLocal);
+	vec3_scale(&pos, -1, &pos);
+	mat4_translate(worldToLocal, &pos, worldToLocal);
+}
+
+void transform_getrotation(Transform* trans, Quat* rot) {
+	*rot = trans->localrotation; 
+	Transform* cur = trans->parent; 
+	while (cur) {
+		quat_multiply(&cur->localrotation, rot, rot);
+	}
+}
+
+