minor comment update

Author: Gin

SerialPrograms/Source/CommonFramework/ImageTools/ImageDiff.h

@@ -32,7 +32,7 @@ void scale_brightness(ImageRGB32& image, const FloatPixel& multiplier);
 //
 //      If (reference.alpha == 255)  Count the pixel.
 //      If (reference.alpha ==   0)  Ignore the pixel and exclude from pixel count.
-//
+//      Alpha channel of "image" is ignored.
 double pixel_RMSD(const ImageViewRGB32& reference, const ImageViewRGB32& image);
 
 
@@ -42,7 +42,7 @@ double pixel_RMSD(const ImageViewRGB32& reference, const ImageViewRGB32& image);
 //
 //      If (reference.alpha == 255)  Count the pixel.
 //      If (reference.alpha ==   0)  Replace reference pixel with "background".
-//
+//      Alpha channel of "image" is ignored.
 double pixel_RMSD(const ImageViewRGB32& reference, const ImageViewRGB32& image, Color background);
 
 

SerialPrograms/Source/CommonTools/ImageMatch/ExactImageMatcher.h

@@ -14,7 +14,7 @@ namespace PokemonAutomation{
 namespace ImageMatch{
 
 
-//  Match images against a template.
+//  Match images against a template image.
 //  Before matching, resize the input image to the template shape and scale template brightness to
 //  match the input image. Alpha channels as used as masks in matching.
 //  No other treatment like tolerating translation or scaling based on stddevs, hence the name "Exact".

SerialPrograms/Source/CommonTools/ImageMatch/WaterfillTemplateMatcher.cpp

@@ -59,22 +59,23 @@ WaterfillTemplateMatcher::WaterfillTemplateMatcher(
         );
     }
 
-    const WaterfillObject* best = &objects[0];
+    const WaterfillObject* largest_object = &objects[0];
     for (const WaterfillObject& object : objects){
-        if (best->area < object.area){
-            best = &object;
+        if (largest_object->area < object.area){
+            largest_object = &object;
         }
     }
 
-    m_matcher.reset(new ExactImageMatcher(extract_box_reference(reference, *best).copy()));
-    m_area_ratio = best->area_ratio();
+    m_matcher.reset(new ExactImageMatcher(extract_box_reference(reference, *largest_object).copy()));
+    m_area_ratio = largest_object->area_ratio();
 
 //    cout << "template area ratio = " << m_area_ratio << endl;
 
     if (PreloadSettings::debug().IMAGE_TEMPLATE_MATCHING){
-        const auto exact_image = extract_box_reference(reference, *best);
+        const auto exact_image = extract_box_reference(reference, *largest_object);
         cout << "Build waterfil template matcher from " << full_path << ", W x H: " << exact_image.width()
-             << " x " << exact_image.height() <<  ", area ratio: " << m_area_ratio << ", Object area: " << best->area << endl;
+             << " x " << exact_image.height() <<  ", area ratio: " << m_area_ratio << ", Object area: "
+             << largest_object->area << endl;
         dump_debug_image(
             global_logger_command_line(),
             "CommonFramework/WaterfillTemplateMatcher",

SerialPrograms/Source/CommonTools/ImageMatch/WaterfillTemplateMatcher.h

@@ -28,11 +28,12 @@ class WaterfillTemplateMatcher{
 
 
 public:
-    // Load a template image from disk, min_color and max_color denote the color range of the object
-    // displayed in the image file while min_area is the minimum number of pixels required for the
-    // object in the template to be loaded.
+    // Load a template image from disk, use waterfill to find the biggest object in the template image that
+    // matches the color range of min_color and max_color. 
+    // min_area is the minimum number of pixels required for the found object in the template.
     // 
-    // The portion of the image holding the found object will get cropped and saved as the actual template image.
+    // The portion of the image holding the biggest object will get cropped and saved as the actual template
+    // image.
     // So if someone changes the template image by padding it to make it larger, as long as the padded color
     // does not fall into [min_color and max_color] range, it will not affect the template matching outcome
     // in any way.
@@ -49,6 +50,7 @@ class WaterfillTemplateMatcher{
     //  Compute RMSD of the current image against the template as-is, using `ExactImageMatcher`.
     // `ExactImageMatcher` will resize the image to match template size and scale template brightness to match the image
     //  before computing RMSD.
+    //  The part of the image template where alpha is 0 is not used to compare with the corresponding part in the input image.
     //  In case the image is invalid, return a large value.
     //  It also calls the virtual function `check_image()` on the image.
     //  If the function returns false, then return a large value. 
@@ -59,7 +61,8 @@ class WaterfillTemplateMatcher{
     //  This cropped image is compared against the template as-is.
     //  The waterfill object's aspect ratio and area ratio are checked against template's. Return a large value 
     //  if the check fails.
-    //  See `double rmsd(const ImageViewRGB32& image) const` on the details of comparing the image against the template.
+    //  See `double rmsd(Resolution input_resolution, const ImageViewRGB32& image) const` on the details of comparing the
+    //  image against the template.
     virtual double rmsd_precropped(
         Resolution input_resolution,
         const ImageViewRGB32& cropped_image,
@@ -71,7 +74,8 @@ class WaterfillTemplateMatcher{
     //  image against the template as-is.
     //  The waterfill object's aspect ratio and area ratio are checked against template's. Return a large value 
     //  if the check fails.
-    //  See `double rmsd(const ImageViewRGB32& image) const` on the details of comparing the image against the template.
+    //  See `double rmsd(Resolution input_resolution, const ImageViewRGB32& image) const` on the details of comparing the
+    //  image against the template.
     virtual double rmsd_original(
         Resolution input_resolution,
         const ImageViewRGB32& original_image,