From 6223edf13f7d35e18c45e35343c0347fb0159b2b Mon Sep 17 00:00:00 2001
From: Marko Luukkainen <marko.luukkainen@semantum.fi>
Date: Wed, 19 Sep 2018 22:41:44 +0300
Subject: [PATCH] Reading background color of a ICanvasContext with SCL

refs #127

Change-Id: I58fd39f4df42643a7aac7441a55c89b6f693cd8d
---
 .../scl/Simantics/Scenegraph.scl              |  2 ++
 .../org/simantics/modeling/SCLScenegraph.java | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/bundles/org.simantics.modeling/scl/Simantics/Scenegraph.scl b/bundles/org.simantics.modeling/scl/Simantics/Scenegraph.scl
index 6a1ecd8fc..3d1170682 100644
--- a/bundles/org.simantics.modeling/scl/Simantics/Scenegraph.scl
+++ b/bundles/org.simantics.modeling/scl/Simantics/Scenegraph.scl
@@ -44,6 +44,8 @@ importJava "org.simantics.modeling.SCLScenegraph" where
     @JavaName getNodeTransform
     getTransform :: ICanvasContext -> String -> String
     
+    getBackgroundColor :: ICanvasContext -> Maybe [Integer]
+    
     @Deprecated
     getICanvasSceneGraphProvider :: Model -> Resource -> String -> <Proc> ICanvasSceneGraphProvider
     
diff --git a/bundles/org.simantics.modeling/src/org/simantics/modeling/SCLScenegraph.java b/bundles/org.simantics.modeling/src/org/simantics/modeling/SCLScenegraph.java
index 754510658..55ed12656 100644
--- a/bundles/org.simantics.modeling/src/org/simantics/modeling/SCLScenegraph.java
+++ b/bundles/org.simantics.modeling/src/org/simantics/modeling/SCLScenegraph.java
@@ -1,6 +1,7 @@
 package org.simantics.modeling;
 
 import java.awt.BasicStroke;
+import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.RenderingHints;
 import java.awt.RenderingHints.Key;
@@ -45,6 +46,7 @@ import org.simantics.diagram.elements.DiagramNodeUtil;
 import org.simantics.diagram.elements.TextGridNode;
 import org.simantics.diagram.elements.TextNode;
 import org.simantics.diagram.stubs.DiagramResource;
+import org.simantics.g2d.canvas.Hints;
 import org.simantics.g2d.canvas.ICanvasContext;
 import org.simantics.g2d.diagram.DiagramHints;
 import org.simantics.g2d.diagram.IDiagram;
@@ -276,6 +278,23 @@ public class SCLScenegraph {
     	}
         return "No nodes in scenegraph!";
     }
+    
+    /**
+     * Returns background color of a canvasContext or null.
+     * @param ctx
+     * @return color in RGBA List<Integer> format, or null.
+     */
+    public static List<Integer> getBackgroundColor(ICanvasContext ctx) {
+    	Color color = ctx.getDefaultHintContext().getHint(Hints.KEY_BACKGROUND_COLOR);
+    	if (color == null)
+    		return null;
+    	ArrayList<Integer> rgba = new ArrayList<>(4);
+    	rgba.add(color.getRed());
+    	rgba.add(color.getGreen());
+    	rgba.add(color.getBlue());
+    	rgba.add(color.getAlpha());
+    	return rgba;
+    }
 
     public static String sceneGraphTest (ICanvasContext ctx, String module, String value) {
     	
-- 
2.43.2