docs: Give an example for GRAPHENE_VEC[234]_LEN
It's useful to show how these symbols are meant to be used.
@@ -40,6 +40,20 @@ GRAPHENE_BEGIN_DECLS
*
* Evaluates to the number of components of a #graphene_vec2_t.
*
+ * This symbol is useful when declaring a C array of floating
+ * point values to be used with graphene_vec2_init_from_float() and
+ * graphene_vec2_to_float(), e.g.
+ *
+ * |[
+ * float v[GRAPHENE_VEC2_LEN];
+ *
+ * // vec is defined elsewhere
+ * graphene_vec2_to_float (&vec, v);
+ *
+ * for (int i = 0; i < GRAPHENE_VEC2_LEN; i++)
+ * fprintf (stdout, "component %d: %g\n", i, v[i]);
+ * ]|
+ *
* Since: 1.0
*/
#define GRAPHENE_VEC2_LEN 2
@@ -49,6 +63,20 @@ GRAPHENE_BEGIN_DECLS
*
* Evaluates to the number of components of a #graphene_vec3_t.
*
+ * This symbol is useful when declaring a C array of floating
+ * point values to be used with graphene_vec3_init_from_float() and
+ * graphene_vec3_to_float(), e.g.
+ *
+ * |[
+ * float v[GRAPHENE_VEC3_LEN];
+ *
+ * // vec is defined elsewhere
+ * graphene_vec3_to_float (&vec, v);
+ *
+ * for (int i = 0; i < GRAPHENE_VEC2_LEN; i++)
+ * fprintf (stdout, "component %d: %g\n", i, v[i]);
+ * ]|
+ *
* Since: 1.0
*/
#define GRAPHENE_VEC3_LEN 3
@@ -58,6 +86,20 @@ GRAPHENE_BEGIN_DECLS
*
* Evaluates to the number of components of a #graphene_vec4_t.
*
+ * This symbol is useful when declaring a C array of floating
+ * point values to be used with graphene_vec4_init_from_float() and
+ * graphene_vec4_to_float(), e.g.
+ *
+ * |[
+ * float v[GRAPHENE_VEC4_LEN];
+ *
+ * // vec is defined elsewhere
+ * graphene_vec4_to_float (&vec, v);
+ *
+ * for (int i = 0; i < GRAPHENE_VEC4_LEN; i++)
+ * fprintf (stdout, "component %d: %g\n", i, v[i]);
+ * ]|
+ *
* Since: 1.0
*/
#define GRAPHENE_VEC4_LEN 4
