1 files changed, 66 insertions, 0 deletions
diff --git a/src/label_formats/large_label_format.rs b/src/label_formats/large_label_format.rs
new file mode 100644
index 0000000..121a4df
--- /dev/null
+++ b/src/label_formats/large_label_format.rs
@@ -0,0 +1,66 @@
+use super::LabelFormat;
+
+pub struct LargeLabelFormat {
+    pub buffer: Vec<u32>,
+    pub width: usize,
+    pub height: usize,
+}
+
+impl std::fmt::Debug for LargeLabelFormat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("LargeLabelFormat")
+            .field("width", &self.width)
+            .field("height", &self.height)
+            .finish()
+    }
+}
+
+fn flood(source: &LargeLabelFormat, destination: &mut Vec<u16>, 
+    x: usize, y: usize,
+    from_color: u32, to_color: u16) {
+    let width = source.width;
+    let destination_color = destination[x + y * width];
+    if destination_color != 0 {
+        return;
+    }
+    let source_color = source.buffer[x + y * width];
+    if source_color != from_color {
+        return;
+    }
+    destination[x + y * width] = to_color;
+    if x > 0 {
+        flood(source, destination, x-1, y, from_color, to_color);
+    }
+    if (x+1) < width {
+        flood(source, destination, x+1, y, from_color, to_color);
+    }
+    if y > 0 {
+        flood(source, destination, x, y-1, from_color, to_color);
+    }
+    if (y+1) < source.height {
+        flood(source, destination, x, y+1, from_color, to_color);
+    }
+}
+
+pub fn compress_large_labels(buffer: LargeLabelFormat) -> LabelFormat {
+    let mut label: u16 = 1;
+    let mut output_buffer: Vec<u16> = vec![0u16; buffer.buffer.len()];
+    for y in 0..buffer.height {
+        for x in 0..buffer.width {
+            let index = x + y*buffer.width;
+            if buffer.buffer[index] == 0 {
+                continue;
+            }
+            if output_buffer[index] == 0 {
+                let color = buffer.buffer[index];
+                flood(&buffer, &mut output_buffer, x, y, color, label);
+                label += 1;
+            }
+        }
+    }
+    return LabelFormat {
+        buffer: output_buffer,
+        width: buffer.width,
+        height: buffer.height,
+    };
+}