Added implementations for MirrorVertically and MirrorHorizontally

Exec/main.cpp

@@ -6,7 +6,7 @@ using namespace Leonetienne::BmpPP;
 
 int main() {
 
-
+/*
     BMP bmp({800, 600}, Colormode::RGB);
 
     for (int x = 0; x < 800; x++)
@@ -21,6 +21,15 @@ int main() {
     }
 
     bmp.Write("write.bmp");
+*/
+
+    BMP bmp("test.bmp");
+
+    //BMP newBmp = bmp.MirrorHorizontally();
+    BMP newBmp = bmp.MirrorVertically();
+
+    if(!newBmp.Write("testwrite.bmp"))
+        std::cerr << "What the hell" << std::endl;
 
     /*
 

Src/BMP.cpp

@@ -211,6 +211,58 @@ namespace Leonetienne::BmpPP {
         return pixelBuffer;
     }
 
+    BMP BMP::MirrorHorizontally() const {
+        // Create a new image matching this's metadata
+        BMP bmp(size, colormode);
+
+        // Now copy over the pixels, mirroring it horizontally
+        const std::size_t numChannels = GetNumChannels();
+        for (std::size_t y = 0; y < size.y; y++) {
+            const std::size_t rowIndex = y * size.x * numChannels;
+
+            for (std::size_t x = 0; x < size.x; x++) {
+                const std::size_t pixelIndex = rowIndex + x * numChannels;
+                const std::size_t flippedPixelIndex = rowIndex + (size.x - 1 - x) * numChannels;
+
+                // Copy over the whole pixel
+                std::copy(
+                  pixelBuffer.cbegin() + flippedPixelIndex,
+                  pixelBuffer.cbegin() + flippedPixelIndex + numChannels,
+                  bmp.pixelBuffer.begin() + pixelIndex
+                );
+            }
+
+        }
+
+        // return it
+        return bmp;
+    }
+
+    BMP BMP::MirrorVertically() const {
+        // Create a new image matching this's metadata
+        BMP bmp(size, colormode);
+
+        const std::size_t numChannels = GetNumChannels();
+        const std::size_t rowLength = size.x * numChannels;
+
+        // Now iterate over all rows, and copy them over, mirroring it vertically
+        for (std::size_t y = 0; y < size.y; y++) {
+            const std::size_t rowIndex = y * rowLength;
+            const std::size_t flippedRowIndex = (size.y - 1 - y) * rowLength;
+
+            // Copy over the whole row
+            std::copy(
+                pixelBuffer.cbegin() + flippedRowIndex,
+                pixelBuffer.cbegin() + flippedRowIndex + rowLength,
+                bmp.pixelBuffer.begin() + rowIndex
+            );
+
+        }
+
+        // return it
+        return bmp;
+    }
+
 }
 
 #undef CHECK_IF_INITIALIZED

Src/BMP.h

@@ -79,10 +79,10 @@ namespace Leonetienne::BmpPP {
         //! Will compare two images for not being exactly identical regarding resolution, bit depth, and pixel values.
         bool operator!=(const BMP& other) const;
 
-        //! Will mirror the image horizontally, and return it as a new image
+        //! Will mirror the image horizontally (flips x axis), and return it as a new image
         BMP MirrorHorizontally() const;
 
-        //! Will mirror the image vertically, and return it as a new image
+        //! Will mirror the image vertically (flips y axis), and return it as a new image
         BMP MirrorVertically() const;
 
         //! Will rotate the image by 90deg, clockwise, and return it as a new image