X-Git-Url: http://www2.svjatoslav.eu/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Feu%2Fsvjatoslav%2Fsixth%2Fe3d%2Fgui%2FViewRenderListener.java;fp=src%2Fmain%2Fjava%2Feu%2Fsvjatoslav%2Fsixth%2Fe3d%2Fgui%2FViewRenderListener.java;h=0977ef7bbefa052a18759e380cd94882c97e06a3;hb=baab2e2c2ad89695293f3136311c585c9a5afed1;hp=0000000000000000000000000000000000000000;hpb=2e7e46514dd35006e9dde07b1959540078292691;p=sixth-3d.git
diff --git a/src/main/java/eu/svjatoslav/sixth/e3d/gui/ViewRenderListener.java b/src/main/java/eu/svjatoslav/sixth/e3d/gui/ViewRenderListener.java
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index 0000000..0977ef7
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+++ b/src/main/java/eu/svjatoslav/sixth/e3d/gui/ViewRenderListener.java
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+/*
+ * Sixth 3D engine. Copyright ©2012-2018, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 3 of the GNU Lesser General Public License
+ * or later as published by the Free Software Foundation.
+ *
+ */
+
+package eu.svjatoslav.sixth.e3d.gui;
+
+public interface ViewRenderListener {
+
+ /**
+ * Notifies that it is about time to render next frame and
+ * allows listener to do any related processing that it needs to.
+ *
+ * Each {@link ViewRenderListener} will be notified exactly once before every frame is rendered.
+ *
+ * {@link ViewRenderListener} can determine if frame repaint is actually
+ * needed from its perspective. Frame will be rendered only if at least one listener says yes.
+ *
+ * @return true
if underlying view shall be re-rendered. If at least one of the view update listeners
+ * returns true
, view is re-rendered.
+ */
+ boolean beforeRender(ViewContext viewContext, final int millisecondsSinceLastFrame);
+}