create and cache new bitmaps from black-on-transparent originals

provided from dict based on player color and whether inverted.  This
works around apparent lack of API to change colors of monochrome
bitmaps at draw time (paralleling those for drawing text.)

xwords4/android/XWords4/src/org/eehouse/android/xw4/BoardView.java

@@ -15,6 +15,9 @@ import android.graphics.drawable.Drawable;
 import android.graphics.drawable.BitmapDrawable;
 import android.content.res.Resources;
 import android.graphics.Paint.FontMetricsInt;
+import java.util.HashMap;
+import java.nio.IntBuffer;
+
 import junit.framework.Assert;
 
 public class BoardView extends View implements DrawCtx, BoardHandler,
@@ -47,6 +50,7 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
     private String m_remText;
     private int m_dictPtr = 0;
     private int m_lastSecsLeft;
+    private HashMap<String,BitmapDrawable> m_bitmapsCache;
 
     // FontDims: exists to translate space available to the largest
     // font we can draw within that space taking advantage of our use
@@ -244,6 +248,13 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
         }
     }
 
+    public void prefsChanged()
+    {
+        synchronized( this ) {
+            m_bitmapsCache = null;
+        }
+    }
+
     // DrawCtxt interface implementation
     public void scoreBegin( Rect rect, int numPlayers, int[] scores, 
                             int remCount, int dfs )
@@ -346,6 +357,10 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
 
         clearToBack( rect );
 
+        if ( owner < 0 ) {
+            owner = 0;
+        }
+
         if ( 0 != (flags & CELL_ISCURSOR) ) {
             backColor = m_otherColors[CommonPrefs.COLOR_FOCUS];
         } else if ( empty ) {
@@ -354,9 +369,6 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
             backColor = BLACK;
         } else {
             backColor = m_otherColors[CommonPrefs.COLOR_TILE_BACK];
-            if ( owner < 0 ) {
-                owner = 0;
-            }
             foreColor = m_playerColors[owner];
         }
 
@@ -374,7 +386,7 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
             } else {
                 Rect smaller = new Rect(rect);
                 smaller.inset( 2, 2 );
-                drawBestBitmap( bitmaps, smaller );
+                drawBestBitmap( text, owner, pending, bitmaps, smaller );
             }
         }
 
@@ -609,7 +621,8 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
             }
             m_letterRect.offsetTo( rect.left+2, rect.top+2 );
             if ( null != bitmaps ) {
-                drawBestBitmap( bitmaps, m_letterRect );
+                drawBestBitmap( text, m_trayOwner, false, bitmaps, 
+                                m_letterRect );
             } else /*if ( null != text )*/ {
                 int height = m_letterRect.height();
                 int descent = m_fontDims.descentFor( height );
@@ -737,7 +750,64 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
         m_canvas.drawRect( rect, m_fillPaint );
     }
 
-    private void drawBestBitmap( BitmapDrawable[] bitmaps, final Rect rect  )
+    private BitmapDrawable colorBitmap( Bitmap base, boolean pending, 
+                                        int owner )
+    {
+        int foreColor, backColor;
+        foreColor = pending? WHITE : m_playerColors[owner];
+        backColor = pending? BLACK : m_otherColors[CommonPrefs.COLOR_TILE_BACK];
+
+        int width = base.getWidth();
+        int height = base.getHeight();
+        IntBuffer intBuffer = IntBuffer.allocate( width * height );
+        base.copyPixelsToBuffer( intBuffer );
+        final int[] oldInts = intBuffer.array();
+        int[] newInts = new int[oldInts.length];
+        for ( int ii = 0; ii < oldInts.length; ++ii ) {
+            int pixel = oldInts[ii];
+            if ( pixel == 0xFF000000 ) {
+                pixel = foreColor;
+            } else {
+                // Note: these pixels though I set them to 00FFFFFF
+                // test == 0 here.  Nonetheless, replacing them works.
+                pixel = backColor;
+            }
+            newInts[ii] = pixel;
+        }
+
+        Bitmap bitmap = Bitmap.createBitmap( newInts, width, height,
+                                             Bitmap.Config.ARGB_8888 );
+        return new BitmapDrawable( bitmap );
+    }
+
+    private BitmapDrawable getColoredBitmap( BitmapDrawable[] blackBmps, 
+                                             String text, int owner, 
+                                             boolean pending, int index )
+    {
+        BitmapDrawable base = blackBmps[index];
+        if ( owner != 0 || pending ) {
+            String key;
+            if ( pending ) {
+                key = String.format( "%s:%d", text, index );
+            } else {
+                key = String.format( "%s:%d:%d", text, owner, index );
+            }
+            if ( null == m_bitmapsCache ) {
+                m_bitmapsCache = new HashMap<String,BitmapDrawable>();
+            }
+            BitmapDrawable found = m_bitmapsCache.get(key);
+            if ( null == found ) {
+                found = colorBitmap( base.getBitmap(), pending, owner );
+                m_bitmapsCache.put( key, found );
+            }
+            base = found;
+        }
+
+        return base;
+    }
+
+    private void drawBestBitmap( String key, int owner, boolean pending,
+                                 BitmapDrawable[] bitmaps, final Rect rect )
     {
         Rect local = new Rect( rect );
         int height = local.height();
@@ -752,9 +822,12 @@ public class BoardView extends View implements DrawCtx, BoardHandler,
             }
         }
 
+        BitmapDrawable bitmap = getColoredBitmap( bitmaps, key, owner, 
+                                                  pending, ii );
+
         // will be 0 if fell through
-        bitmaps[ii].setBounds( local );
-        bitmaps[ii].draw( m_canvas );
+        bitmap.setBounds( local );
+        bitmap.draw( m_canvas );
     }
 
 }