Add implicit/explicit conversion functions from Rgba<U> to Rgba<T> etc.

ComputationalBiomechanicsLab · Aug 29, 2024 · 6539793 · 6539793
1 parent 44032cd
commit 6539793
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Showing 6 changed files with 55 additions and 37 deletions.
diff --git a/src/oscar/Graphics/Color.cpp b/src/oscar/Graphics/Color.cpp
@@ -132,16 +132,6 @@ Color osc::lerp(const Color& a, const Color& b, float t)
     return Color{lerp(Vec4{a}, Vec4{b}, saturate(t))};
 }
 
-Color32 osc::to_color32(const Color& color)
-{
-    return to_color32(static_cast<Vec4>(color));
-}
-
-Color32 osc::to_color32(const Vec4& vec)
-{
-    return Color32{vec.x, vec.y, vec.z, vec.w};
-}
-
 Color32 osc::to_color32(float r, float g, float b, float a)
 {
     return Color32{r, g, b, a};
@@ -157,16 +147,6 @@ Color32 osc::to_color32(uint32_t v)
     };
 }
 
-Color osc::to_color(Color32 color)
-{
-    return Color{
-        color.r.normalized_value(),
-        color.g.normalized_value(),
-        color.b.normalized_value(),
-        color.a.normalized_value(),
-    };
-}
-
 Color osc::clamp_to_ldr(const Color& color)
 {
     return Color{saturate(Vec4{color})};
@@ -229,7 +209,7 @@ std::string osc::to_html_string_rgba(const Color& color)
     std::string rv;
     rv.reserve(9);
     rv.push_back('#');
-    for (auto component : to_color32(color)) {
+    for (auto component : Color32{color}) {
         auto [nibble_1, nibble_2] = to_hex_chars(static_cast<uint8_t>(component));
         rv.push_back(nibble_1);
         rv.push_back(nibble_2);

diff --git a/src/oscar/Graphics/Color.h b/src/oscar/Graphics/Color.h
@@ -51,11 +51,8 @@ namespace osc
     Color lerp(const Color& a, const Color& b, float t);
 
     // float-/double-based inputs assume normalized color range (i.e. 0 to 1)
-    Color32 to_color32(const Color&);
-    Color32 to_color32(const Vec4&);
     Color32 to_color32(float, float, float, float);
     Color32 to_color32(uint32_t);  // R at MSB
-    Color to_color(Color32);
 
     // returns the color as a hexadecimal string in the format "#rrggbbaa", as
     // commonly-used in web applications, configuration files, etc.

diff --git a/src/oscar/Graphics/Rgba.h b/src/oscar/Graphics/Rgba.h
@@ -144,6 +144,15 @@ namespace osc
             r{v.x}, g{v.y}, b{v.z}, a{v.w}
         {}
 
+        template<ColorComponent U>
+        requires std::constructible_from<T, const U&>
+        explicit constexpr Rgba(const Vec<4, U>& v) :
+            r{static_cast<T>(v.x)},
+            g{static_cast<T>(v.y)},
+            b{static_cast<T>(v.z)},
+            a{static_cast<T>(v.w)}
+        {}
+
         constexpr Rgba(value_type r_, value_type g_, value_type b_, value_type a_) :
             r{r_}, g{g_}, b{b_}, a{a_}
         {}
@@ -152,6 +161,16 @@ namespace osc
             r{r_}, g{g_}, b{b_}, a(1.0f)
         {}
 
+        template<ColorComponent U>
+        requires std::constructible_from<T, const U&>
+        explicit (not (std::convertible_to<U, T>))
+        constexpr Rgba(const Rgba<U>& v) :
+            r{static_cast<T>(v.r)},
+            g{static_cast<T>(v.g)},
+            b{static_cast<T>(v.b)},
+            a{static_cast<T>(v.a)}
+        {}
+
         constexpr reference operator[](size_type pos)
         {
             static_assert(sizeof(Rgba) == 4*sizeof(value_type));

diff --git a/tests/testoscar/Graphics/TestColor.cpp b/tests/testoscar/Graphics/TestColor.cpp
@@ -255,7 +255,7 @@ TEST(Color, to_linear_colorspace_followed_by_to_srgb_colorspace_on_Color_returns
     ASSERT_NEAR(original_color.a, converted_color.a, tolerance);
 }
 
-TEST(Color, to_color32_returns_RGBA32_version_of_the_color)
+TEST(Color, conversion_to_Color32_returns_RGBA32_version_of_the_color)
 {
     const Color color = {0.85f, 0.62f, 0.3f, 0.5f};
     const Color32 expected = {
@@ -265,34 +265,34 @@ TEST(Color, to_color32_returns_RGBA32_version_of_the_color)
         static_cast<uint8_t>(color.a * static_cast<float>(0xff)),
     };
 
-    const Color32 got = to_color32(color);
+    const Color32 got = Color32{color};
 
     ASSERT_EQ(expected.r, got.r);
     ASSERT_EQ(expected.g, got.g);
     ASSERT_EQ(expected.b, got.b);
     ASSERT_EQ(expected.a, got.a);
 }
 
-TEST(Color, to_color32_clamps_HDR_color_components)
+TEST(Color, conversion_to_Color32_clamps_HDR_color_components)
 {
     const Color hdr_color = {1.5f, 0.0f, 2.0f, 1.0f};
     const Color32 expected = {0xff, 0x00, 0xff, 0xff};
-    ASSERT_EQ(to_color32(hdr_color), expected);
+    ASSERT_EQ(Color32(hdr_color), expected);
 }
 
-TEST(Color, to_color32_clamps_negative_color_components)
+TEST(Color, conversion_to_Color32_clamps_negative_color_components)
 {
     const Color color = {-1.0f, 0.0f, 1.0f, 1.0f};
     const Color32 expected = {0x00, 0x00, 0xff, 0xff};
-    ASSERT_EQ(to_color32(color), expected);
+    ASSERT_EQ(Color32{color}, expected);
 }
 
-TEST(Color, to_color_on_Color32_returns_expected_colors)
+TEST(Color32, conversion_to_Color_returns_expected_colors)
 {
-    ASSERT_EQ(to_color(Color32(0xff, 0x00, 0x00, 0xff)), Color(1.0f, 0.0f, 0.0f, 1.0f));
-    ASSERT_EQ(to_color(Color32(0x00, 0xff, 0x00, 0xff)), Color(0.0f, 1.0f, 0.0f, 1.0f));
-    ASSERT_EQ(to_color(Color32(0x00, 0x00, 0xff, 0xff)), Color(0.0f, 0.0f, 1.0f, 1.0f));
-    ASSERT_EQ(to_color(Color32(0x00, 0xff, 0xff, 0x00)), Color(0.0f, 1.0f, 1.0f, 0.0f));
+    ASSERT_EQ(Color(Color32(0xff, 0x00, 0x00, 0xff)), Color(1.0f, 0.0f, 0.0f, 1.0f));
+    ASSERT_EQ(Color(Color32(0x00, 0xff, 0x00, 0xff)), Color(0.0f, 1.0f, 0.0f, 1.0f));
+    ASSERT_EQ(Color(Color32(0x00, 0x00, 0xff, 0xff)), Color(0.0f, 0.0f, 1.0f, 1.0f));
+    ASSERT_EQ(Color(Color32(0x00, 0xff, 0xff, 0x00)), Color(0.0f, 1.0f, 1.0f, 0.0f));
 }
 
 TEST(Color, black_returns_black_color)

diff --git a/tests/testoscar/Graphics/TestMesh.cpp b/tests/testoscar/Graphics/TestMesh.cpp
@@ -1733,7 +1733,7 @@ TEST(Mesh, set_vertex_buffer_params_can_be_used_to_reformat_a_float_attribute_to
     });
 
     const auto expected = project_into_vector(colors, [](const Color& c) {
-        return to_color(to_color32(c));
+        return Color{Color32{c}};
     });
 
     ASSERT_EQ(m.colors(), expected);
@@ -1863,7 +1863,7 @@ TEST(Mesh, set_vertex_buffer_data_works_as_expected_for_ImGui_style_case)
     };
     const std::vector<SimilarToImGuiVert> data(16);
     const auto expected_vertices = project_into_vector(data, [](const auto& v) { return Vec3{v.pos, 0.0f}; });
-    const auto expected_colors = project_into_vector(data, [](const auto& v) { return to_color(v.col); });
+    const auto expected_colors = project_into_vector(data, [](const auto& v) { return Color(v.col); });
     const auto expected_texture_coordinates = project_into_vector(data, [](const auto& v) { return v.uv; });
 
     Mesh mesh;

diff --git a/tests/testoscar/Graphics/TestRgba.cpp b/tests/testoscar/Graphics/TestRgba.cpp
@@ -2,6 +2,7 @@
 
 #include <gtest/gtest.h>
 #include <oscar/Graphics/Unorm8.h>
+#include <oscar/Maths/Vec4.h>
 
 #include <sstream>
 
@@ -97,3 +98,24 @@ TEST(Rgba, Unorm8_rgba_can_be_hashed)
         last_hash = hash;
     }
 }
+
+TEST(Rgba, can_implicitly_construct_Rgba_from_different_components_if_components_are_implicitly_convertible)
+{
+    const Rgba<float> float_val{0.0f, 0.5f, 1.0f, 1.0f};
+    const Rgba<Unorm8> unorm8_val = float_val;
+
+    ASSERT_EQ(unorm8_val.r, 0.0f);
+    ASSERT_EQ(unorm8_val.g, Unorm8{127});
+    ASSERT_EQ(unorm8_val.b, 1.0f);
+    ASSERT_EQ(unorm8_val.a, Unorm8{0xff});
+}
+
+TEST(Rgba, can_explicitly_construct_from_Vec4_of_different_type)
+{
+    const Rgba<Unorm8> unorm8_val{Vec4{0.0f, 0.5f, 1.0f, 1.0f}};
+
+    ASSERT_EQ(unorm8_val.r, 0.0f);
+    ASSERT_EQ(unorm8_val.g, Unorm8{127});
+    ASSERT_EQ(unorm8_val.b, 1.0f);
+    ASSERT_EQ(unorm8_val.a, Unorm8{0xff});
+}