finder_pattern and finder_patern_info port

src/qrcode/detector/finder_pattern.rs

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+use crate::RXingResultPoint;
+
+/**
+ * <p>Encapsulates a finder pattern, which are the three square patterns found in
+ * the corners of QR Codes. It also encapsulates a count of similar finder patterns,
+ * as a convenience to the finder's bookkeeping.</p>
+ *
+ * @author Sean Owen
+ */
+pub struct FinderPattern {
+    estimatedModuleSize: f32,
+    count: usize,
+    internal_result_point: RXingResultPoint,
+}
+
+impl FinderPattern {
+    pub fn new(posX: f32, posY: f32, estimatedModuleSize: f32) -> Self {
+        Self::private_new(posX, posY, estimatedModuleSize, 1)
+    }
+
+    fn private_new(posX: f32, posY: f32, estimatedModuleSize: f32, count: usize) -> Self {
+        Self {
+            estimatedModuleSize,
+            count,
+            internal_result_point: RXingResultPoint::new(posX, posY),
+        }
+    }
+
+    pub fn getEstimatedModuleSize(&self) -> f32 {
+        self.estimatedModuleSize
+    }
+
+    pub fn getCount(&self) -> usize {
+        self.count
+    }
+
+    /**
+     * <p>Determines if this finder pattern "about equals" a finder pattern at the stated
+     * position and size -- meaning, it is at nearly the same center with nearly the same size.</p>
+     */
+    pub fn aboutEquals(&self, moduleSize: f32, i: f32, j: f32) -> bool {
+        if (i - self.internal_result_point.getY()).abs() <= moduleSize
+            && (j - self.internal_result_point.getX()).abs() <= moduleSize
+        {
+            let moduleSizeDiff = (moduleSize - self.estimatedModuleSize).abs();
+            return moduleSizeDiff <= 1.0 || moduleSizeDiff <= self.estimatedModuleSize;
+        }
+        return false;
+    }
+
+    /**
+     * Combines this object's current estimate of a finder pattern position and module size
+     * with a new estimate. It returns a new {@code FinderPattern} containing a weighted average
+     * based on count.
+     */
+    pub fn combineEstimate(&self, i: f32, j: f32, newModuleSize: f32) -> FinderPattern {
+        let combinedCount = self.count as f32 + 1.0;
+        let combinedX = (self.count as f32 * self.internal_result_point.getX() + j) / combinedCount;
+        let combinedY = (self.count as f32 * self.internal_result_point.getY() + i) / combinedCount;
+        let combinedModuleSize =
+            (self.count as f32 * self.estimatedModuleSize + newModuleSize) / combinedCount;
+        FinderPattern::private_new(
+            combinedX,
+            combinedY,
+            combinedModuleSize,
+            combinedCount.floor() as usize,
+        )
+    }
+}