[gnome-color-manager] trivial: add gcm_vec3_add() and gcm_vec3_subtract()

[Richard Hughes <rhughes src gnome org>]

commit 8b9fbc9dcfe4be535397c0fbbe374265a5f69c7a
Author: Richard Hughes <richard hughsie com>
Date:   Sun Aug 1 18:58:31 2010 +0100

    trivial: add gcm_vec3_add() and gcm_vec3_subtract()

 libcolor-glib/gcm-common.c |   34 ++++++++++++++++++++++++++++++++++
 libcolor-glib/gcm-common.h |    6 ++++++
 2 files changed, 40 insertions(+), 0 deletions(-)
---
diff --git a/libcolor-glib/gcm-common.c b/libcolor-glib/gcm-common.c
index d2a648a..7d3534a 100644
--- a/libcolor-glib/gcm-common.c
+++ b/libcolor-glib/gcm-common.c
@@ -65,6 +65,40 @@ gcm_vec3_scalar_multiply (const GcmVec3 *src, gdouble value, GcmVec3 *dest)
 }
 
 /**
+ * gcm_vec3_add:
+ * @src1: the source
+ * @src2: the other source
+ * @dest: the destination
+ *
+ * Adds two vector quantaties
+ * The arguments @src and @dest can be the same value.
+ **/
+void
+gcm_vec3_add (const GcmVec3 *src1, const GcmVec3 *src2, GcmVec3 *dest)
+{
+	dest->v0 = src1->v0 + src2->v0;
+	dest->v1 = src1->v1 + src2->v1;
+	dest->v2 = src1->v2 + src2->v2;
+}
+
+/**
+ * gcm_vec3_subtract:
+ * @src1: the source
+ * @src2: the other source
+ * @dest: the destination
+ *
+ * Subtracts one vector quantaty from another
+ * The arguments @src and @dest can be the same value.
+ **/
+void
+gcm_vec3_subtract (const GcmVec3 *src1, const GcmVec3 *src2, GcmVec3 *dest)
+{
+	dest->v0 = src1->v0 - src2->v0;
+	dest->v1 = src1->v1 - src2->v1;
+	dest->v2 = src1->v2 - src2->v2;
+}
+
+/**
  * gcm_vec3_to_string:
  * @src: the source
  *
diff --git a/libcolor-glib/gcm-common.h b/libcolor-glib/gcm-common.h
index acdb33e..f561871 100644
--- a/libcolor-glib/gcm-common.h
+++ b/libcolor-glib/gcm-common.h
@@ -41,6 +41,12 @@ typedef struct {
 } GcmVec3;
 
 void		 gcm_vec3_clear			(GcmVec3		*src);
+void		 gcm_vec3_add			(const GcmVec3		*src1,
+						 const GcmVec3		*src2,
+						 GcmVec3		*dest);
+void		 gcm_vec3_subtract		(const GcmVec3		*src1,
+						 const GcmVec3		*src2,
+						 GcmVec3		*dest);
 void		 gcm_vec3_scalar_multiply	(const GcmVec3		*src,
 						 gdouble		 value,
 						 GcmVec3		*dest);