Add cogl_primitive_copy()

This adds a public function to make a copy of a primitive. The copy is
shallow which means it will share the same attributes and attribute
buffers. This could be useful for code that wants to have multiple
similar primitives with slightly modified properties.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

2 files changed, 31 insertions, 0 deletions

diff --git a/cogl/cogl-primitive.c b/cogl/cogl-primitive.c
index a88f1899..10983cd6 100644
--- a/cogl/cogl-primitive.c
+++ b/cogl/cogl-primitive.c
@@ -525,6 +525,22 @@ cogl_primitive_set_indices (CoglPrimitive *primitive,
 }
 
 CoglPrimitive *
+cogl_primitive_copy (CoglPrimitive *primitive)
+{
+  CoglPrimitive *copy;
+
+  copy = cogl_primitive_new_with_attributes (primitive->mode,
+                                             primitive->n_vertices,
+                                             primitive->attributes,
+                                             primitive->n_attributes);
+
+  cogl_primitive_set_indices (copy, primitive->indices, primitive->n_vertices);
+  cogl_primitive_set_first_vertex (copy, primitive->first_vertex);
+
+  return copy;
+}
+
+CoglPrimitive *
 _cogl_primitive_immutable_ref (CoglPrimitive *primitive)
 {
   int i;
diff --git a/cogl/cogl-primitive.h b/cogl/cogl-primitive.h
index c9529a05..62293ab6 100644
--- a/cogl/cogl-primitive.h
+++ b/cogl/cogl-primitive.h
@@ -775,6 +775,21 @@ cogl_primitive_set_indices (CoglPrimitive *primitive,
                             int n_indices);
 
 /**
+ * cogl_primitive_copy:
+ * @primitive: A primitive copy
+ *
+ * Makes a copy of an existing #CoglPrimitive. Note that the primitive
+ * is a shallow copy which means it will use the same attributes and
+ * attribute buffers as the original primitive.
+ *
+ * Return value: the new primitive
+ * Since: 1.10
+ * Stability: unstable
+ */
+CoglPrimitive *
+cogl_primitive_copy (CoglPrimitive *primitive);
+
+/**
  * cogl_primitive_draw:
  * @primitive: A #CoglPrimitive object
  *