Added getBlackDiagonal() which I likely want to use later

git-svn-id: https://zxing.googlecode.com/svn/trunk@968 59b500cc-1b3d-0410-9834-0bbf25fbcc57

core/src/com/google/zxing/MonochromeBitmapSource.java

@@ -54,6 +54,8 @@ public interface MonochromeBitmapSource {
    */
   BitArray getBlackColumn(int x, BitArray column, int startY, int getHeight);
 
+  BitArray getBlackDiagonal(int x, int y, int dx, int dy, BitArray diagonal, int size);
+
   /**
    * @return height of underlying image
    */
@@ -110,7 +112,7 @@ public interface MonochromeBitmapSource {
    * @param y The y coordinate in the image.
    * @return The luminance value between 0 and 255.
    */
-  public abstract int getLuminance(int x, int y);
+  int getLuminance(int x, int y);
 
   /**
    * This is the main mechanism for retrieving luminance data. It is dramatically more efficient
@@ -123,7 +125,7 @@ public interface MonochromeBitmapSource {
    *            but then I will take pity on you and allocate a sufficient array internally.
    * @return The array containing the luminance data. This is the same as row if it was usable.
    */
-  public abstract int[] getLuminanceRow(int y, int[] row);
+  int[] getLuminanceRow(int y, int[] row);
 
   /**
    * The same as getLuminanceRow(), but for columns.
@@ -132,6 +134,6 @@ public interface MonochromeBitmapSource {
    * @param column The array to write luminance values into. See above.
    * @return The array containing the luminance data.
    */
-  public abstract int[] getLuminanceColumn(int x, int[] column);
+  int[] getLuminanceColumn(int x, int[] column);
 
 }

core/src/com/google/zxing/common/BaseMonochromeBitmapSource.java

@@ -106,6 +106,22 @@ public abstract class BaseMonochromeBitmapSource implements MonochromeBitmapSour
     return column;
   }
 
+  public BitArray getBlackDiagonal(int x, int y, int dx, int dy, BitArray diagonal, int size) {
+    if (diagonal == null || diagonal.getSize() < size) {
+      diagonal = new BitArray(size);
+    } else {
+      diagonal.clear();
+    }
+    for (int i = 0; i < size; i++) {
+      if (isBlack(x, y)) {
+        diagonal.set(i);
+      }
+      x += dx;
+      y += dy;
+    }
+    return diagonal;
+  }
+
   public void estimateBlackPoint(BlackPointEstimationMethod method, int argument)
       throws ReaderException {
     if (!method.equals(lastMethod) || argument != lastArgument) {

core/src/com/google/zxing/common/CroppedMonochromeBitmapSource.java

@@ -21,7 +21,7 @@ import com.google.zxing.MonochromeBitmapSource;
 import com.google.zxing.ReaderException;
 
 /**
- * Encapulates a cropped region of another {@link com.google.zxing.MonochromeBitmapSource}.
+ * Encapulates a cropped region of another {@link MonochromeBitmapSource}.
  *
  * @author Sean Owen
  */
@@ -72,6 +72,10 @@ public final class CroppedMonochromeBitmapSource implements MonochromeBitmapSour
     return right - left;
   }
 
+  public BitArray getBlackDiagonal(int x, int y, int dx, int dy, BitArray diagonal, int size) {
+    return delegate.getBlackDiagonal(left + x, top + y, dx, dy, diagonal, size);
+  }
+
   public void estimateBlackPoint(BlackPointEstimationMethod method, int argument)
       throws ReaderException {
     // Hmm, the delegate will probably base this on the whole image though...