Enhance lane drawing functionality with filled lane area and improved color coding

lane_detection.py

@@ -18,7 +18,9 @@ def region_of_interest(img, vertices):
 
 def draw_lines(img, lines, color=[0, 255, 0], thickness=3):
     """
-    Draw lines on the image.
+    Draw lines on the image with filled lane area.
+    - Lane lines: Red color
+    - Lane interior: Green semi-transparent fill
     """
     if lines is None:
         return img
@@ -69,13 +71,30 @@ def draw_lines(img, lines, color=[0, 255, 0], thickness=3):
     left_line = average_lines(left_lines, img.shape)
     right_line = average_lines(right_lines, img.shape)
     
+    # Fill the lane area with green color
+    if left_line is not None and right_line is not None:
+        # Create polygon points for the lane area
+        lane_polygon = np.array([[
+            (left_line[0], left_line[1]),   # Left bottom
+            (left_line[2], left_line[3]),   # Left top
+            (right_line[2], right_line[3]), # Right top
+            (right_line[0], right_line[1])  # Right bottom
+        ]], dtype=np.int32)
+        
+        # Fill the lane area with green (semi-transparent)
+        cv2.fillPoly(line_img, lane_polygon, (0, 255, 0))
+    
+    # Draw the lane lines in red with thicker lines
     if left_line is not None:
-        cv2.line(line_img, (left_line[0], left_line[1]), (left_line[2], left_line[3]), color, thickness)
+        cv2.line(line_img, (left_line[0], left_line[1]), (left_line[2], left_line[3]), 
+                 (0, 0, 255), thickness * 2)  # Red color (BGR format)
     
     if right_line is not None:
-        cv2.line(line_img, (right_line[0], right_line[1]), (right_line[2], right_line[3]), color, thickness)
+        cv2.line(line_img, (right_line[0], right_line[1]), (right_line[2], right_line[3]), 
+                 (0, 0, 255), thickness * 2)  # Red color (BGR format)
     
-    return cv2.addWeighted(img, 1.0, line_img, 1.0, 0)
+    # Blend with original image (make the overlay semi-transparent)
+    return cv2.addWeighted(img, 0.8, line_img, 0.5, 0)
 
 
 def process_frame(frame):