Move Windows WGL context attributes to renderer gl

docs/modernization/build-inventory.md

@@ -231,6 +231,9 @@ Known local toolchain state:
   readback format/type, framebuffer copy targets, and renderbuffer/depth
   attachment parameters; `src/canvas.cpp` no longer contains raw `GL_*`
   constants.
+  Windows desktop OpenGL context creation now consumes a tested
+  `windows_wgl_core_context_3_3_config()` catalog from `pp_renderer_gl` instead
+  of owning active WGL context/pixel-format attribute literals in `main.cpp`.
 - `windows-msvc-vcpkg-headless` validates manifest install/configure/build/test
   for the current headless component matrix; see DEBT-0007 for remaining app
   and platform triplet migration.

docs/modernization/roadmap.md

@@ -776,6 +776,10 @@ Results:
   framebuffer copy targets, and renderbuffer/depth attachment parameters through
   the renderer GL backend mapping; `src/canvas.cpp` no longer contains raw
   `GL_*` constants.
+- Windows desktop OpenGL context creation now consumes a tested
+  `windows_wgl_core_context_3_3_config()` catalog from `pp_renderer_gl`, moving
+  the active WGL context/pixel-format attribute literals out of the platform
+  entrypoint.
 - Known remaining warnings: legacy project/vendor diagnostics, Visual Studio
   vcpkg-manifest warning, `LNK4099` missing libyuv PDBs, and `LNK4098` runtime
   library conflict from retained vendor binaries.

src/main.cpp

@@ -974,28 +974,7 @@ int main(int argc, char** argv)
     // If supported create a 3.3 context
     if (GLAD_WGL_ARB_create_context)
     {
-        int contex_attribs[] =
+        const auto wgl_config = pp::renderer::gl::windows_wgl_core_context_3_3_config();
-        {
-            WGL_CONTEXT_MAJOR_VERSION_ARB, 3,
-            WGL_CONTEXT_MINOR_VERSION_ARB, 3,
-            WGL_CONTEXT_FLAGS_ARB, WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
-            WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_CORE_PROFILE_BIT_ARB,
-            0
-        };
-        int pixel_attribs[] = 
-        {
-            WGL_DRAW_TO_WINDOW_ARB, GL_TRUE,
-            WGL_SUPPORT_OPENGL_ARB, GL_TRUE,
-            WGL_DOUBLE_BUFFER_ARB, GL_TRUE,
-            WGL_ACCELERATION_ARB,WGL_FULL_ACCELERATION_ARB,
-            WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB,
-            WGL_COLOR_BITS_ARB, 24,
-            WGL_DEPTH_BITS_ARB, 16,
-            //WGL_STENCIL_BITS_ARB, 8,
-            //WGL_SAMPLE_BUFFERS_ARB, 1, // Number of buffers (must be 1 at time of writing)
-            //WGL_SAMPLES_ARB, 4,        // Number of samples
-            0
-        };
         UINT numFormat;
 
         wglMakeCurrent(NULL, NULL);
@@ -1007,9 +986,9 @@ int main(int argc, char** argv)
             (float)(clientRect.bottom - clientRect.top), 0, 0, hInst, 0);
 
         hDC = GetDC(hWnd);
-        wglChoosePixelFormatARB(hDC, pixel_attribs, nullptr, 1, &pxfmt, &numFormat);
+        wglChoosePixelFormatARB(hDC, wgl_config.pixel_format_attributes.data(), nullptr, 1, &pxfmt, &numFormat);
         SetPixelFormat(hDC, pxfmt, &pfd);
-        hRC = wglCreateContextAttribsARB(hDC, NULL, contex_attribs);
+        hRC = wglCreateContextAttribsARB(hDC, NULL, wgl_config.context_attributes.data());
         wglMakeCurrent(hDC, hRC);
     }
     else

src/renderer_gl/opengl_capabilities.cpp

@@ -114,6 +114,21 @@ constexpr std::uint32_t gl_stream_read = 0x88E1U;
 constexpr std::uint32_t gl_map_read_bit = 0x0001U;
 constexpr std::uint8_t gl_boolean_false = 0U;
 constexpr std::uint8_t gl_boolean_true = 1U;
+constexpr std::int32_t wgl_draw_to_window_arb = 0x2001;
+constexpr std::int32_t wgl_acceleration_arb = 0x2003;
+constexpr std::int32_t wgl_support_opengl_arb = 0x2010;
+constexpr std::int32_t wgl_double_buffer_arb = 0x2011;
+constexpr std::int32_t wgl_pixel_type_arb = 0x2013;
+constexpr std::int32_t wgl_color_bits_arb = 0x2014;
+constexpr std::int32_t wgl_depth_bits_arb = 0x2022;
+constexpr std::int32_t wgl_full_acceleration_arb = 0x2027;
+constexpr std::int32_t wgl_type_rgba_arb = 0x202B;
+constexpr std::int32_t wgl_context_major_version_arb = 0x2091;
+constexpr std::int32_t wgl_context_minor_version_arb = 0x2092;
+constexpr std::int32_t wgl_context_flags_arb = 0x2094;
+constexpr std::int32_t wgl_context_forward_compatible_bit_arb = 0x0002;
+constexpr std::int32_t wgl_context_profile_mask_arb = 0x9126;
+constexpr std::int32_t wgl_context_core_profile_bit_arb = 0x00000001;
 
 [[nodiscard]] bool contains(std::string_view text, std::string_view needle) noexcept
 {
@@ -741,4 +756,27 @@ std::uint32_t sampler_border_color_parameter_name() noexcept
     return gl_texture_border_color;
 }
 
+OpenGlWindowsWglContextConfig windows_wgl_core_context_3_3_config() noexcept
+{
+    return {
+        .context_attributes = {
+            wgl_context_major_version_arb, 3,
+            wgl_context_minor_version_arb, 3,
+            wgl_context_flags_arb, wgl_context_forward_compatible_bit_arb,
+            wgl_context_profile_mask_arb, wgl_context_core_profile_bit_arb,
+            0,
+        },
+        .pixel_format_attributes = {
+            wgl_draw_to_window_arb, static_cast<std::int32_t>(gl_boolean_true),
+            wgl_support_opengl_arb, static_cast<std::int32_t>(gl_boolean_true),
+            wgl_double_buffer_arb, static_cast<std::int32_t>(gl_boolean_true),
+            wgl_acceleration_arb, wgl_full_acceleration_arb,
+            wgl_pixel_type_arb, wgl_type_rgba_arb,
+            wgl_color_bits_arb, 24,
+            wgl_depth_bits_arb, 16,
+            0,
+        },
+    };
+}
+
 }

src/renderer_gl/opengl_capabilities.h

@@ -38,6 +38,11 @@ struct OpenGlReadbackFormat {
     std::uint32_t bytes_per_pixel = 0;
 };
 
+struct OpenGlWindowsWglContextConfig {
+    std::array<std::int32_t, 9> context_attributes {};
+    std::array<std::int32_t, 15> pixel_format_attributes {};
+};
+
 [[nodiscard]] OpenGlCapabilities detect_opengl_capabilities(
     std::span<const std::string_view> extensions,
     OpenGlRuntime runtime) noexcept;
@@ -141,5 +146,6 @@ struct OpenGlReadbackFormat {
     std::uint32_t filter_min,
     std::uint32_t filter_mag) noexcept;
 [[nodiscard]] std::uint32_t sampler_border_color_parameter_name() noexcept;
+[[nodiscard]] OpenGlWindowsWglContextConfig windows_wgl_core_context_3_3_config() noexcept;
 
 }

tests/renderer_gl/capabilities_tests.cpp

@@ -364,6 +364,39 @@ void maps_app_initialization_parameters(pp::tests::Harness& h)
     PP_EXPECT(h, pp::renderer::gl::active_texture_unit(4U) == 0x84C4U);
 }
 
+void maps_windows_wgl_core_context_parameters(pp::tests::Harness& h)
+{
+    const auto config = pp::renderer::gl::windows_wgl_core_context_3_3_config();
+
+    PP_EXPECT(h, config.context_attributes.size() == 9U);
+    PP_EXPECT(h, config.context_attributes[0] == 0x2091);
+    PP_EXPECT(h, config.context_attributes[1] == 3);
+    PP_EXPECT(h, config.context_attributes[2] == 0x2092);
+    PP_EXPECT(h, config.context_attributes[3] == 3);
+    PP_EXPECT(h, config.context_attributes[4] == 0x2094);
+    PP_EXPECT(h, config.context_attributes[5] == 0x0002);
+    PP_EXPECT(h, config.context_attributes[6] == 0x9126);
+    PP_EXPECT(h, config.context_attributes[7] == 0x00000001);
+    PP_EXPECT(h, config.context_attributes[8] == 0);
+
+    PP_EXPECT(h, config.pixel_format_attributes.size() == 15U);
+    PP_EXPECT(h, config.pixel_format_attributes[0] == 0x2001);
+    PP_EXPECT(h, config.pixel_format_attributes[1] == 1);
+    PP_EXPECT(h, config.pixel_format_attributes[2] == 0x2010);
+    PP_EXPECT(h, config.pixel_format_attributes[3] == 1);
+    PP_EXPECT(h, config.pixel_format_attributes[4] == 0x2011);
+    PP_EXPECT(h, config.pixel_format_attributes[5] == 1);
+    PP_EXPECT(h, config.pixel_format_attributes[6] == 0x2003);
+    PP_EXPECT(h, config.pixel_format_attributes[7] == 0x2027);
+    PP_EXPECT(h, config.pixel_format_attributes[8] == 0x2013);
+    PP_EXPECT(h, config.pixel_format_attributes[9] == 0x202B);
+    PP_EXPECT(h, config.pixel_format_attributes[10] == 0x2014);
+    PP_EXPECT(h, config.pixel_format_attributes[11] == 24);
+    PP_EXPECT(h, config.pixel_format_attributes[12] == 0x2022);
+    PP_EXPECT(h, config.pixel_format_attributes[13] == 16);
+    PP_EXPECT(h, config.pixel_format_attributes[14] == 0);
+}
+
 void rejects_invalid_shader_attribute_binding_catalogs(pp::tests::Harness& h)
 {
     const std::array<pp::renderer::gl::OpenGlAttributeBinding, 0> empty {};
@@ -457,6 +490,7 @@ int main()
     harness.run("maps_sampler_parameters", maps_sampler_parameters);
     harness.run("exposes_shader_attribute_binding_catalog", exposes_shader_attribute_binding_catalog);
     harness.run("maps_app_initialization_parameters", maps_app_initialization_parameters);
+    harness.run("maps_windows_wgl_core_context_parameters", maps_windows_wgl_core_context_parameters);
     harness.run("rejects_invalid_shader_attribute_binding_catalogs", rejects_invalid_shader_attribute_binding_catalogs);
     harness.run("exposes_shader_uniform_catalog", exposes_shader_uniform_catalog);
     harness.run("rejects_invalid_shader_uniform_catalogs", rejects_invalid_shader_uniform_catalogs);