add Color::to_rgba32 and Color::to_hex

Author: jube

include/gf2/core/Color.h

@@ -5,6 +5,8 @@
 
 #include <cstdint>
 
+#include <array>
+
 #include "CoreApi.h"
 #include "Math.h"
 #include "TypeTraits.h"
@@ -24,18 +26,29 @@ namespace gf {
 
     constexpr Color(uint32_t rgb, uint8_t a = 255)
     // clang-format off
-    : r(static_cast<float>((rgb >> 16) & 0xFF) / 255.0f)
-    , g(static_cast<float>((rgb >> 8)  & 0xFF) / 255.0f)
-    , b(static_cast<float>((rgb >> 0)  & 0xFF) / 255.0f)
+    : r(float((rgb >> 16) & 0xFF) / 255.0f)
+    , g(float((rgb >> 8)  & 0xFF) / 255.0f)
+    , b(float((rgb >> 0)  & 0xFF) / 255.0f)
     // clang-format on
-    , a(static_cast<float>(a) / 255.0f)
+    , a(float(a) / 255.0f)
     {
     }
 
     float r;
     float g;
     float b;
     float a;
+
+    constexpr std::array<uint8_t, 4> to_rgba32() const
+    {
+      return { uint8_t(r * 255), uint8_t(g * 255), uint8_t(b * 255), uint8_t(a * 255) };
+    }
+
+    constexpr uint32_t to_hex() const
+    {
+      const auto rgba = to_rgba32();
+      return (rgba[0] << 24) + (rgba[1] << 16) + (rgba[2] << 8) + (rgba[3] << 0);
+    }
   };
 
   constexpr bool operator==(Color lhs, Color rhs)

tests/tests_core_Color.cc

@@ -12,11 +12,11 @@ TEST(ColorTest, DefaultConstructor) {
   EXPECT_FLOAT_EQ(color0.b, 0.0f);
   EXPECT_FLOAT_EQ(color0.a, 0.0f);
 
-  constexpr gf::Color ccolor0;
-  static_assert(ccolor0.r == 0.0f, "Check Color");
-  static_assert(ccolor0.g == 0.0f, "Check Color");
-  static_assert(ccolor0.b == 0.0f, "Check Color");
-  static_assert(ccolor0.a == 0.0f, "Check Color");
+  constexpr gf::Color Color0;
+  static_assert(Color0.r == 0.0f);
+  static_assert(Color0.g == 0.0f);
+  static_assert(Color0.b == 0.0f);
+  static_assert(Color0.a == 0.0f);
 }
 
 TEST(ColorTest, Constructor) {
@@ -34,17 +34,17 @@ TEST(ColorTest, Constructor) {
   EXPECT_FLOAT_EQ(color1.b, 1.0f);
   EXPECT_FLOAT_EQ(color1.a, 0.5f);
 
-  constexpr gf::Color ccolor0(0.0f, 0.5f, 1.0f);
-  static_assert(ccolor0.r == 0.0f, "Check Color");
-  static_assert(ccolor0.g == 0.5f, "Check Color");
-  static_assert(ccolor0.b == 1.0f, "Check Color");
-  static_assert(ccolor0.a == 1.0f, "Check Color");
-
-  constexpr gf::Color ccolor1(0.0f, 0.5f, 1.0f, 0.5f);
-  static_assert(ccolor1.r == 0.0f, "Check Color");
-  static_assert(ccolor1.g == 0.5f, "Check Color");
-  static_assert(ccolor1.b == 1.0f, "Check Color");
-  static_assert(ccolor1.a == 0.5f, "Check Color");
+  constexpr gf::Color Color0(0.0f, 0.5f, 1.0f);
+  static_assert(Color0.r == 0.0f);
+  static_assert(Color0.g == 0.5f);
+  static_assert(Color0.b == 1.0f);
+  static_assert(Color0.a == 1.0f);
+
+  constexpr gf::Color Color1(0.0f, 0.5f, 1.0f, 0.5f);
+  static_assert(Color1.r == 0.0f);
+  static_assert(Color1.g == 0.5f);
+  static_assert(Color1.b == 1.0f);
+  static_assert(Color1.a == 0.5f);
 }
 
 TEST(ColorTest, Rgba) {
@@ -62,32 +62,32 @@ TEST(ColorTest, Rgba) {
   EXPECT_FLOAT_EQ(color1.b, 0.0f);
   EXPECT_FLOAT_EQ(color1.a, 0.0f);
 
-  constexpr gf::Color ccolor0(0x00FF00);
-  static_assert(ccolor0.r == 0.0f, "Check Color");
-  static_assert(ccolor0.g == 1.0f, "Check Color");
-  static_assert(ccolor0.b == 0.0f, "Check Color");
-  static_assert(ccolor0.a == 1.0f, "Check Color");
-
-  constexpr gf::Color ccolor1(0x00FF00, 0x00);
-  static_assert(ccolor1.r == 0.0f, "Check Color");
-  static_assert(ccolor1.g == 1.0f, "Check Color");
-  static_assert(ccolor1.b == 0.0f, "Check Color");
-  static_assert(ccolor1.a == 0.0f, "Check Color");
+  constexpr gf::Color Color0(0x00FF00);
+  static_assert(Color0.r == 0.0f);
+  static_assert(Color0.g == 1.0f);
+  static_assert(Color0.b == 0.0f);
+  static_assert(Color0.a == 1.0f);
+
+  constexpr gf::Color Color1(0x00FF00, 0x00);
+  static_assert(Color1.r == 0.0f);
+  static_assert(Color1.g == 1.0f);
+  static_assert(Color1.b == 0.0f);
+  static_assert(Color1.a == 0.0f);
 }
 
 TEST(ColorTest, Equality) {
-  gf::Color color0(0x12345678);
-  gf::Color color1(0x12345678);
-  gf::Color color2(0x87654321);
+  gf::Color color0(0x123456, 0x78);
+  gf::Color color1(0x123456, 0x78);
+  gf::Color color2(0x876543, 0x21);
 
   EXPECT_EQ(color0, color1);
   EXPECT_NE(color0, color2);
 
-  constexpr gf::Color ccolor0(0x12345678);
-  constexpr gf::Color ccolor1(0x12345678);
-  constexpr gf::Color ccolor2(0x87654321);
-  static_assert(ccolor0 == ccolor1, "Check Color");
-  static_assert(ccolor0 != ccolor2, "Check Color");
+  constexpr gf::Color Color0(0x123456, 0x78);
+  constexpr gf::Color Color1(0x123456, 0x78);
+  constexpr gf::Color Color2(0x876543, 0x21);
+  static_assert(Color0 == Color1);
+  static_assert(Color0 != Color2);
 }
 
 TEST(ColorTest, Addition) {
@@ -104,11 +104,11 @@ TEST(ColorTest, Addition) {
   color1 += 0.5f;
   EXPECT_EQ(color1, gf::Color(1.5f, 1.0f, 0.5f, 0.5f));
 
-  constexpr gf::Color ccolor0(0.0f, 0.5f, 1.0f, 1.0f);
-  constexpr gf::Color ccolor1(1.0f, 0.5f, 0.0f, 0.0f);
-  static_assert(ccolor0 + ccolor1 == gf::Color(1.0f, 1.0f, 1.0f, 1.0f), "Check Color");
-  static_assert(ccolor0 + 0.5f == gf::Color(0.5f, 1.0f, 1.5f, 1.5f), "Check Color");
-  static_assert(0.5f + ccolor1 == gf::Color(1.5f, 1.0f, 0.5f, 0.5f), "Check Color");
+  constexpr gf::Color Color0(0.0f, 0.5f, 1.0f, 1.0f);
+  constexpr gf::Color Color1(1.0f, 0.5f, 0.0f, 0.0f);
+  static_assert(Color0 + Color1 == gf::Color(1.0f, 1.0f, 1.0f, 1.0f));
+  static_assert(Color0 + 0.5f == gf::Color(0.5f, 1.0f, 1.5f, 1.5f));
+  static_assert(0.5f + Color1 == gf::Color(1.5f, 1.0f, 0.5f, 0.5f));
 }
 
 TEST(ColorTest, Substraction) {
@@ -125,18 +125,18 @@ TEST(ColorTest, Substraction) {
   color1 -= 0.5f;
   EXPECT_EQ(color1, gf::Color(0.0f, 0.0f, -0.5f, -0.5f));
 
-  constexpr gf::Color ccolor0(1.0f, 0.5f, 1.0f, 1.0f);
-  constexpr gf::Color ccolor1(0.5f, 0.5f, 0.0f, 0.0f);
-  static_assert(ccolor0 - ccolor1 == gf::Color(0.5f, 0.0f, 1.0f, 1.0f), "Check Color");
-  static_assert(ccolor0 - 0.5f == gf::Color(0.5f, 0.0f, 0.5f, 0.5f), "Check Color");
-  static_assert(0.5f - ccolor1 == gf::Color(0.0f, 0.0f, 0.5f, 0.5f), "Check Color");
+  constexpr gf::Color Color0(1.0f, 0.5f, 1.0f, 1.0f);
+  constexpr gf::Color Color1(0.5f, 0.5f, 0.0f, 0.0f);
+  static_assert(Color0 - Color1 == gf::Color(0.5f, 0.0f, 1.0f, 1.0f));
+  static_assert(Color0 - 0.5f == gf::Color(0.5f, 0.0f, 0.5f, 0.5f));
+  static_assert(0.5f - Color1 == gf::Color(0.0f, 0.0f, 0.5f, 0.5f));
 }
 
 TEST(ColorTest, Multiplication) {
   gf::Color color0(1.0f, 1.0f, 0.5f, 0.5f);
   gf::Color color1(1.0f, 0.5f, 0.5f, 1.0f);
 
-  EXPECT_EQ(color0* color1, gf::Color(1.0f, 0.5f, 0.25f, 0.5f));
+  EXPECT_EQ(color0 * color1, gf::Color(1.0f, 0.5f, 0.25f, 0.5f));
   EXPECT_EQ(color0 * 0.5f, gf::Color(0.5f, 0.5f, 0.25f, 0.25f));
   EXPECT_EQ(0.5f * color1, gf::Color(0.5f, 0.25f, 0.25f, 0.5f));
 
@@ -146,11 +146,11 @@ TEST(ColorTest, Multiplication) {
   color1 *= 0.5f;
   EXPECT_EQ(color1, gf::Color(0.5f, 0.25f, 0.25f, 0.5f));
 
-  constexpr gf::Color ccolor0(1.0f, 1.0f, 0.5f, 0.5f);
-  constexpr gf::Color ccolor1(1.0f, 0.5f, 0.5f, 1.0f);
-  static_assert(ccolor0 * ccolor1 == gf::Color(1.0f, 0.5f, 0.25f, 0.5f), "Check Color");
-  static_assert(ccolor0 * 0.5f == gf::Color(0.5f, 0.5f, 0.25f, 0.25f), "Check Color");
-  static_assert(0.5f * ccolor1 == gf::Color(0.5f, 0.25f, 0.25f, 0.5f), "Check Color");
+  constexpr gf::Color Color0(1.0f, 1.0f, 0.5f, 0.5f);
+  constexpr gf::Color Color1(1.0f, 0.5f, 0.5f, 1.0f);
+  static_assert(Color0 * Color1 == gf::Color(1.0f, 0.5f, 0.25f, 0.5f));
+  static_assert(Color0 * 0.5f == gf::Color(0.5f, 0.5f, 0.25f, 0.25f));
+  static_assert(0.5f * Color1 == gf::Color(0.5f, 0.25f, 0.25f, 0.5f));
 }
 
 TEST(ColorTest, Division) {
@@ -167,11 +167,11 @@ TEST(ColorTest, Division) {
   color1 /= 0.5f;
   EXPECT_EQ(color1, gf::Color(2.0f, 2.0f, 1.0f, 1.0f));
 
-  constexpr gf::Color ccolor0(1.0f, 0.5f, 0.5f, 1.0f);
-  constexpr gf::Color ccolor1(1.0f, 1.0f, 0.5f, 0.5f);
-  static_assert(ccolor0 / ccolor1 == gf::Color(1.0f, 0.5f, 1.0f, 2.0f), "Check Color");
-  static_assert(ccolor0 / 0.5f == gf::Color(2.0f, 1.0f, 1.0f, 2.0f), "Check Color");
-  static_assert(0.5f / ccolor1 == gf::Color(0.5f, 0.5f, 1.0f, 1.0f), "Check Color");
+  constexpr gf::Color Color0(1.0f, 0.5f, 0.5f, 1.0f);
+  constexpr gf::Color Color1(1.0f, 1.0f, 0.5f, 0.5f);
+  static_assert(Color0 / Color1 == gf::Color(1.0f, 0.5f, 1.0f, 2.0f));
+  static_assert(Color0 / 0.5f == gf::Color(2.0f, 1.0f, 1.0f, 2.0f));
+  static_assert(0.5f / Color1 == gf::Color(0.5f, 0.5f, 1.0f, 1.0f));
 }
 
 TEST(ColorTest, Opaque) {
@@ -186,9 +186,35 @@ TEST(ColorTest, Opaque) {
   gf::Color color = gf::opaque();
   EXPECT_EQ(color.a, 0.5f);
 
-  constexpr gf::Color ccolor = gf::opaque(0.3f);
-  static_assert(ccolor.r == 1.0f, "Check Color");
-  static_assert(ccolor.g == 1.0f, "Check Color");
-  static_assert(ccolor.b == 1.0f, "Check Color");
-  static_assert(ccolor.a == 0.3f, "Check Color");
+  constexpr gf::Color Color = gf::opaque(0.3f);
+  static_assert(Color.r == 1.0f);
+  static_assert(Color.g == 1.0f);
+  static_assert(Color.b == 1.0f);
+  static_assert(Color.a == 0.3f);
+}
+
+TEST(ColorTest, ToRgba32) {
+  gf::Color color0(0x123456, 0x78);
+  auto rgba = color0.to_rgba32();
+  EXPECT_EQ(rgba[0], 0x12);
+  EXPECT_EQ(rgba[1], 0x34);
+  EXPECT_EQ(rgba[2], 0x56);
+  EXPECT_EQ(rgba[3], 0x78);
+
+  constexpr gf::Color Color0(0x123456, 0x78);
+  constexpr auto Rgba = Color0.to_rgba32();
+  static_assert(Rgba[0] == 0x12);
+  static_assert(Rgba[1] == 0x34);
+  static_assert(Rgba[2] == 0x56);
+  static_assert(Rgba[3] == 0x78);
+}
+
+TEST(ColorTest, ToHex) {
+  gf::Color color0(0x123456, 0x78);
+  auto hex = color0.to_hex();
+  EXPECT_EQ(hex, 0x12345678);
+
+  constexpr gf::Color Color0(0x123456, 0x78);
+  constexpr auto Hex = Color0.to_hex();
+  static_assert(Hex == 0x12345678);
 }