Added HighlightTileRenderer (thanks in part to rockNme2349)

configuration.txt

@@ -43,6 +43,14 @@ worlds:
             prefix: t
             maximumheight: 127
             colorscheme: default
+          #- class: org.dynmap.kzedmap.HighlightTileRenderer
+          #  prefix: ht
+          #  maximumheight: 127
+          #  colorscheme: default
+          #  highlight: # For highlighting multiple block-types.
+          #    - 56 # Highlight diamond-ore
+          #    - 66 # Highlight minecart track
+          #  highlight: 56 # For highlighting a single block-type.
           - class: org.dynmap.kzedmap.CaveTileRenderer
             prefix: ct
             maximumheight: 127
@@ -101,6 +109,10 @@ web:
             title: Surface
             name: surface
             prefix: t
+          #- type: KzedMapType
+          #  title: Highlighted Map
+          #  name: highlight
+          #  prefix: ht
           - type: KzedMapType
             title: Cave
             name: cave

src/main/java/org/dynmap/kzedmap/DefaultTileRenderer.java

@@ -5,6 +5,7 @@ import java.awt.image.BufferedImage;
 import java.awt.image.WritableRaster;
 import java.io.File;
 import java.io.IOException;
+import java.util.HashSet;
 import java.util.Map;
 
 import javax.imageio.ImageIO;
@@ -15,9 +16,12 @@ import org.dynmap.debug.Debug;
 
 public class DefaultTileRenderer implements MapTileRenderer {
     protected static final Color translucent = new Color(0, 0, 0, 0);
-    private String name;
+    protected String name;
     protected int maximumHeight = 127;
-    private ColorScheme colorScheme;
+    protected ColorScheme colorScheme;
+    
+    protected HashSet<Integer> highlightBlocks = new HashSet<Integer>();
+    protected Color highlightColor = new Color(255, 0, 0);
 
     @Override
     public String getName() {
@@ -135,6 +139,9 @@ public class DefaultTileRenderer implements MapTileRenderer {
             seq = (seq + 1) & 3;
 
             if (id != 0) {
+                if (highlightBlocks.contains(id)) {
+                    return highlightColor;
+                }
                 Color[] colors = colorScheme.colors.get(id);
                 if (colors != null) {
                     Color c = colors[seq];

src/main/java/org/dynmap/kzedmap/HighlightTileRenderer.java

@@ -0,0 +1,93 @@
+package org.dynmap.kzedmap;
+
+import java.awt.Color;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+
+import org.bukkit.World;
+
+public class HighlightTileRenderer extends DefaultTileRenderer {
+    protected HashSet<Integer> highlightBlocks = new HashSet<Integer>();
+
+    public HighlightTileRenderer(Map<String, Object> configuration) {
+        super(configuration);
+        Object highlightObj = configuration.get("highlight");
+        if (highlightObj instanceof List<?>) {
+            for(Object o : (List<?>)highlightObj) {
+                highlightBlocks.add((Integer)o);
+            }
+        } else if (highlightObj instanceof Integer) {
+            highlightBlocks.add((Integer)highlightObj);
+        }
+    }
+
+    @Override
+    protected Color scan(World world, int x, int y, int z, int seq) {
+        Color result = translucent;
+        for (;;) {
+            if (y < 0) {
+                break;
+            }
+
+            int id = world.getBlockTypeIdAt(x, y, z);
+
+            switch (seq) {
+            case 0:
+                x--;
+                break;
+            case 1:
+                y--;
+                break;
+            case 2:
+                z++;
+                break;
+            case 3:
+                y--;
+                break;
+            }
+
+            seq = (seq + 1) & 3;
+
+            if (id != 0) {
+                Color[] colors = colorScheme.colors.get(id);
+                if (colors != null) {
+                    Color c = colors[seq];
+
+                    if (highlightBlocks.contains(id)) {
+                        return c;
+                    }
+
+                    if (c.getAlpha() > 0) {
+
+                        /* we found something that isn't transparent! */
+                        /*
+                         * if (c.getAlpha() == 255) { return c; }
+                         */
+                        /* this block is transparent, so recurse */
+                        
+                        // No need to blend if result is opaque.
+                        if (result.getAlpha() < 255) { 
+                            Color bg = c;
+                            c = result;
+                            
+                            int cr = c.getRed();
+                            int cg = c.getGreen();
+                            int cb = c.getBlue();
+                            int ca = c.getAlpha();
+                            cr *= ca;
+                            cg *= ca;
+                            cb *= ca;
+                            int na = 255 - ca;
+    
+                            result = new Color((bg.getRed() * na + cr) >> 8, (bg.getGreen() * na + cg) >> 8, (bg.getBlue() * na + cb) >> 8,
+                                Math.min(255, bg.getAlpha()+c.getAlpha()) // Not really correct, but gets the job done without recursion while still looking ok.
+                                );
+                        }
+                    }
+                }
+            }
+        }
+        return result;
+    }
+}

web/js/map.js

@@ -282,8 +282,11 @@ DynMap.prototype = {
 		$.each(me.options.components, function(index, configuration) {
 			loadjs('js/' + configuration.type + '.js', function() {
 				var componentconstructor = componentconstructors[configuration.type];
-				me.components.push(new componentconstructor(me, configuration));
+				if (componentconstructor) {
-				
+					me.components.push(new componentconstructor(me, configuration));
+				} else {
+					// Could not load component. We'll ignore this for the moment.
+				}
 				componentstoload--;
 				if (componentstoload == 0) {
 					// Actually start updating once all components are loaded.