Added ColorConverter interface and RgbaToBgr impl

Porytiles-2.x/include/porytiles/Color/Bgr15.h

@@ -16,7 +16,8 @@ namespace porytiles::color {
  * and red respectively. Internally, a Bgr15 is representing using a 16-bit integer, with the top
  * bit left unused. Bgr15 is the preferred color format for the Game Boy Advance's palette RAM. The
  * BGR format has no concept of transparency. Since all Colors must provide an implementation of
- * @link Color::computeAlphaComponent computeAlphaComponent @endlink, Bgr15 simply returns an opaque value.
+ * @link Color::computeAlphaComponent computeAlphaComponent @endlink, Bgr15 simply returns an opaque
+ * value.
  */
 class Bgr15 : public Color {
     std::uint16_t bgr;
@@ -101,7 +102,7 @@ class Bgr15 : public Color {
      */
     [[nodiscard]] std::uint8_t computeAlphaComponent() const override
     {
-        return Rgba32::ALPHA_OPAQUE;
+        return ALPHA_OPAQUE;
     }
 
     /**

Porytiles-2.x/include/porytiles/Color/Color.h

@@ -2,7 +2,7 @@
 #define PORYTILES_COLOR_COLOR_H
 
 #include <cstdint>
-#include <iostream>
+#include <string>
 
 namespace porytiles::color {
 

Porytiles-2.x/include/porytiles/Color/ColorConverter.h

@@ -0,0 +1,20 @@
+#ifndef PORYTILES_COLOR_COLOR_CONVERTER_H
+#define PORYTILES_COLOR_COLOR_CONVERTER_H
+
+#include <porytiles/Color/Color.h>
+
+namespace porytiles::color {
+
+/**
+ * @brief Service interface for a converter service that transforms one Color implementation into a
+ * different Color implementation.
+ */
+class ColorConverter {
+  public:
+    virtual ~ColorConverter() = default;
+    [[nodiscard]] virtual std::unique_ptr<Color> convert(const Color &input) const = 0;
+};
+
+} // namespace porytiles::color
+
+#endif // PORYTILES_COLOR_COLOR_CONVERTER_H

Porytiles-2.x/include/porytiles/Color/Palette.h

@@ -14,7 +14,7 @@ class Palette {
     [[nodiscard]] virtual std::size_t getCapacity() const = 0;
     [[nodiscard]] virtual std::size_t getSize() const = 0;
     virtual void pushColor(const Color &color) = 0;
-    [[nodiscard]] virtual const Color& colorAt(std::size_t index) const = 0;
+    [[nodiscard]] virtual const Color &colorAt(std::size_t index) const = 0;
 };
 
 } // namespace porytiles::color

Porytiles-2.x/include/porytiles/Color/Rgba32Palette.h

@@ -20,7 +20,7 @@ class Rgba32Palette : public Palette {
     [[nodiscard]] std::size_t getCapacity() const override;
     [[nodiscard]] std::size_t getSize() const override;
     void pushColor(const Color &color) override;
-    [[nodiscard]] const Color& colorAt(std::size_t index) const override;
+    [[nodiscard]] const Color &colorAt(std::size_t index) const override;
 };
 
 } // namespace porytiles::color

Porytiles-2.x/include/porytiles/Color/RgbaToBgr.h

@@ -0,0 +1,20 @@
+#ifndef PORYTILES_COLOR_RGBA_TO_BGR_H
+#define PORYTILES_COLOR_RGBA_TO_BGR_H
+
+#include <porytiles/Color/Color.h>
+#include <porytiles/Color/ColorConverter.h>
+
+namespace porytiles::color {
+
+/**
+ * @brief Service interface for a converter service that transforms one Color implementation into a
+ * different Color implementation.
+ */
+class RgbaToBgr : public ColorConverter {
+public:
+    [[nodiscard]] std::unique_ptr<Color> convert(const Color &input) const override;
+};
+
+} // namespace porytiles::color
+
+#endif // PORYTILES_COLOR_RGBA_TO_BGR_H

Porytiles-2.x/lib/Color/RgbaToBgr.cpp

@@ -0,0 +1,14 @@
+#include "porytiles/Color/RgbaToBgr.h"
+
+#include <porytiles/Color/Bgr15.h>
+#include <porytiles/Color/Rgba32.h>
+
+using namespace porytiles::color;
+
+std::unique_ptr<Color> RgbaToBgr::convert(const Color &input) const
+{
+    const auto &rgb = dynamic_cast<const Rgba32 &>(input);
+    const Bgr15 bgr{rgb.computeRedComponent(), rgb.computeGreenComponent(),
+                    rgb.computeBlueComponent()};
+    return std::make_unique<Bgr15>(bgr);
+}

Porytiles-2.x/tests/Color/Bgr15Test.cpp

@@ -27,3 +27,16 @@ TEST(Bgr15Test, TestComponentCtor)
     const Bgr15 bgr{255, 255, 255};
     EXPECT_EQ(bgr.getRawValue(), TWO_FIFTEENTH_POW_MINUS_ONE);
 }
+
+TEST(Bgr15Test, TestComponentGetters)
+{
+    using namespace porytiles::color;
+
+    const Bgr15 bgr{255, 255, 255};
+    // expected component value is 248 due to precision loss
+    constexpr std::uint8_t expectedComponentValue = 248;
+    EXPECT_EQ(bgr.computeRedComponent(), expectedComponentValue);
+    EXPECT_EQ(bgr.computeGreenComponent(), expectedComponentValue);
+    EXPECT_EQ(bgr.computeBlueComponent(), expectedComponentValue);
+    EXPECT_EQ(bgr.computeAlphaComponent(), Color::ALPHA_OPAQUE);
+}

Porytiles-2.x/tests/Color/RgbaToBgrTest.cpp

@@ -0,0 +1,22 @@
+#include <gtest/gtest.h>
+
+#include <porytiles/Color/Bgr15.h>
+#include <porytiles/Color/Rgba32.h>
+#include <porytiles/Color/RgbaToBgr.h>
+
+TEST(RgbaToBgrTest, RgbaToBgr)
+{
+    using namespace porytiles::color;
+
+    const RgbaToBgr rgbaToBgr{};
+
+    const Rgba32 redRgba1{255, 0, 0};
+    const Bgr15 redBgr1{31};
+    const auto convertedBgr1 = rgbaToBgr.convert(redRgba1);
+    EXPECT_EQ(dynamic_cast<const Bgr15 &>(*convertedBgr1), redBgr1);
+
+    const Rgba32 redRgba2{250, 0, 0};
+    const auto convertedBgr2 = rgbaToBgr.convert(redRgba2);
+    // should still match redBgr1 due to precision loss between formats
+    EXPECT_EQ(dynamic_cast<const Bgr15 &>(*convertedBgr2), redBgr1);
+}