added gwinImageNext()

include/gwin/image.h

@@ -104,6 +104,26 @@ bool_t gwinImageOpenMemory(GHandle gh, const void* memory);
  */
 gdispImageError gwinImageCache(GHandle gh);
 
+
+/**
+ * @brief	Prepare for the next frame/page in the image file.
+ * @return	A time in milliseconds to keep displaying the current frame before trying to draw
+ * 			the next frame. Watch out for the special values TIME_IMMEDIATE and TIME_INFINITE.
+ * 
+ * @param[in] gh   The widget handle (must be an image box handle)
+ * 
+ * @pre		gwinImageOpenXxx() must have returned successfully.
+ *
+ * @note	It will return TIME_IMMEDIATE if the first frame/page hasn't been drawn or if the next frame
+ * 			should be drawn immediately.
+ * @note	It will return TIME_INFINITE if another image frame doesn't exist or an error has occurred.
+ * @note	Images that support multiple pages (eg TIFF files) will return TIME_IMMEDIATE between pages
+ * 			and then TIME_INFINITE when there are no more pages.
+ * @note	An image that displays a looped animation will never return TIME_INFINITE unless it
+ * 			gets an error.
+ */
+delaytime_t gwinImageNext(GHandle gh);
+
 #ifdef __cplusplus
 }
 #endif

src/gwin/gimage.c

@@ -171,5 +171,9 @@ gdispImageError gwinImageCache(GHandle gh) {
 	return gdispImageCache(&widget(gh)->image);
 }
 
+delaytime_t gwinImageNext(GHandle gh) {
+	return gdispImageNext(&widget(gh)->image);
+}
+
 #endif // GFX_USE_GWIN && GWIN_NEED_IMAGE
 /** @} */