Updating documentation

ppapi/c/pp_point.h

Index: ppapi/c/pp_point.h
===================================================================
--- ppapi/c/pp_point.h	(revision 73626)
+++ ppapi/c/pp_point.h	(working copy)
@@ -7,7 +7,8 @@
 
 /**
  * @file
- * Defines the API ...
+ * This file defines the API to create a 2 dimensional point.
+ * 0,0 is the upper-left starting coordinate.
  */
 
 #include "ppapi/c/pp_macros.h"
@@ -18,8 +19,21 @@
  * @addtogroup Structs
  * @{
  */
+
+/**
+ * The PP_Point structure defines the x and y coordinates of a point.
+ */
 struct PP_Point {
+  /**
+   * This value represents the horizontal coordinate of a point, starting with 0
+   * as the left-most coordinate.
+   */
   int32_t x;
+
+  /**
+   * This value represents the vertical coordinate of a point, starting with 0
+   * as the top-most coordinate.
+   */
   int32_t y;
 };
 PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_Point, 8);
@@ -31,6 +45,16 @@
  * @addtogroup Functions
  * @{
  */
+
+/**
+ * PP_MakePoint() creates a PP_Point given the x and y coordinates as int32_t
+ * values.
+ * @param[in] x An int32_t value representing a horizontal coordinate of a
+ * point, starting with 0 as the left-most coordinate.
+ * @param[in] y An int32_t value representing a vertical coordinate of a point,
+ * starting with 0 as the top-most coordinate.
+ * @return A PP_Point structure.
+ */
 PP_INLINE struct PP_Point PP_MakePoint(int32_t x, int32_t y) {
   struct PP_Point ret;
   ret.x = x;