From 4a9ded5b39ed08e13abc2cddba8b712f62b983f2 Mon Sep 17 00:00:00 2001
From: Anthony Towns <aj@erisian.com.au>
Date: Sun, 21 Nov 2010 17:39:50 +1000
Subject: [PATCH] AltosSiteMap: ensure buffer around active tile

---
 ao-tools/altosui/AltosSiteMap.java     | 53 ++++++++++++++++++++------
 ao-tools/altosui/AltosSiteMapTile.java | 17 ++++++---
 2 files changed, 53 insertions(+), 17 deletions(-)

diff --git a/ao-tools/altosui/AltosSiteMap.java b/ao-tools/altosui/AltosSiteMap.java
index b2d79043..802eb68c 100644
--- a/ao-tools/altosui/AltosSiteMap.java
+++ b/ao-tools/altosui/AltosSiteMap.java
@@ -260,29 +260,57 @@ public class AltosSiteMap extends JScrollPane implements AltosFlightDisplay {
 				if (0 <= ref.y && ref.y < px_size)
 					in_any = true;
 		}
-		if (!in_any) {
-			final AltosSiteMapTile tile = new AltosSiteMapTile(px_size);
-			final Point offset = tileOffset(pt);
-			mapTiles.put(offset, tile);
 
+		Point offset = tileOffset(pt);
+		if (!in_any) {
 			Point2D.Double ref, lref;
 			ref = translatePoint(pt, tileCoordOffset(offset));
 			lref = translatePoint(last_pt, tileCoordOffset(offset));
-			tile.show(state, crc_errors, lref, ref);
 
+			AltosSiteMapTile tile = createTile(offset);
+			tile.show(state, crc_errors, lref, ref);
 			initMap(tile, offset);
+			finishTileLater(tile, offset);
+		}
 
-			SwingUtilities.invokeLater( new Runnable() {
-				public void run() {
-					addTileAt(tile, offset);
-					setViewportView(comp);
-				}
-			} );
+		if (offset != tileOffset(last_pt)) {
+			ensureTilesAround(offset);
 		}
+
 		last_pt = pt;
 		last_state = state.state;
 	}
 
+	private AltosSiteMapTile createTile(final Point offset) {
+		final AltosSiteMapTile tile = new AltosSiteMapTile(px_size);
+		mapTiles.put(offset, tile);
+		return tile;
+	}
+	private void finishTileLater(final AltosSiteMapTile tile,
+				     final Point offset)
+	{
+		SwingUtilities.invokeLater( new Runnable() {
+			public void run() {
+				addTileAt(tile, offset);
+				tile.setScrollable();
+			}
+		} );
+	}
+
+	private void ensureTilesAround(Point base_offset) {
+		for (int x = -1; x <= 1; x++) {
+			for (int y = -1; y <= 1; y++) {
+				Point offset = new Point(base_offset.x + x, base_offset.y + y);
+				if (mapTiles.containsKey(offset))
+					continue;
+				AltosSiteMapTile tile = createTile(offset);
+				initMap(tile, offset);
+				finishTileLater(tile, offset);
+			}
+		}
+	}
+
+
 	private void addTileAt(AltosSiteMapTile tile, Point offset) {
 		if (Math.abs(offset.x) >= MAX_TILE_DELTA ||
 				Math.abs(offset.y) >= MAX_TILE_DELTA)
@@ -328,10 +356,11 @@ public class AltosSiteMap extends JScrollPane implements AltosFlightDisplay {
 
 		for (int x = -1; x <= 1; x++) {
 			for (int y = -1; y <= 1; y++) {
-				AltosSiteMapTile t = new AltosSiteMapTile(px_size);
 				Point offset = new Point(x, y);
+				AltosSiteMapTile t = new AltosSiteMapTile(px_size);
 				mapTiles.put(offset, t);
 				addTileAt(t, offset);
+				t.setScrollable();
 			}
 		}
 		setViewportView(comp);
diff --git a/ao-tools/altosui/AltosSiteMapTile.java b/ao-tools/altosui/AltosSiteMapTile.java
index ea8c8bd9..e0942986 100644
--- a/ao-tools/altosui/AltosSiteMapTile.java
+++ b/ao-tools/altosui/AltosSiteMapTile.java
@@ -52,10 +52,17 @@ public class AltosSiteMapTile extends JLayeredPane {
 		Color.BLACK   // landed
 	};
 
-	boolean drawn_landed_circle = false;
-	boolean drawn_boost_circle = false;
-	public void show(AltosState state, int crc_errors,
-			 Point2D.Double last_pt, Point2D.Double pt)
+	private boolean drawn_landed_circle = false;
+	private boolean drawn_boost_circle = false;
+	private boolean scrollable = false;
+	public synchronized void setScrollable() {
+		scrollable = true;
+	}
+	public synchronized boolean isScrollable() {
+		return scrollable;
+	}
+	public synchronized void show(AltosState state, int crc_errors,
+				      Point2D.Double last_pt, Point2D.Double pt)
 	{
 		if (0 <= state.state && state.state < stateColors.length) {
 			g2d.setColor(stateColors[state.state]);
@@ -63,7 +70,7 @@ public class AltosSiteMapTile extends JLayeredPane {
 		g2d.draw(new Line2D.Double(last_pt, pt));
 
 		int px_size = getWidth();
-		if (0 <= pt.x && pt.x < px_size) {
+		if (isScrollable() && 0 <= pt.x && pt.x < px_size) {
 			if (0 <= pt.y && pt.y < px_size) {
 				int dx = 500, dy = 250;
 				if (state.state > 2) {
-- 
2.30.2