Map renderer blit filters to OpenGL

docs/modernization/build-inventory.md

@@ -195,7 +195,8 @@ Known local toolchain state:
   tokens used by `Texture2D`, plus cube-map binding and allocation face targets
   used by `TextureCube`. It also owns and
   validates framebuffer blit color mask and linear/nearest filters used by
-  `RTT::resize` and `RTT::copy`, plus the default linear clamp-to-edge
+  `RTT::resize` and `RTT::copy`, renderer API blit-filter to OpenGL token
+  mapping, plus the default linear clamp-to-edge
   render-target texture parameters, texture/renderbuffer targets, depth format,
   framebuffer targets, binding queries, attachment points, and completion
   status used by `RTT::create` and framebuffer bind/restore paths, plus RTT

docs/modernization/roadmap.md

@@ -449,7 +449,8 @@ face targets, RGBA allocation format, and unsigned-byte component type also
 delegate to `pp_renderer_gl`. RGBA8/RGBA32F readback formats, checked byte-count math, and PBO
 pixel-buffer target/usage/access tokens used by `RTT` and `PBO` readbacks now
 live in `pp_renderer_gl`. The framebuffer blit color mask and linear/nearest
-filter tokens used by `RTT::resize` and `RTT::copy`, plus the default
+filter tokens used by `RTT::resize` and `RTT::copy`, renderer API blit-filter
+to OpenGL token mapping, plus the default
 render-target texture parameters, texture/renderbuffer targets, depth format,
 framebuffer targets, binding queries, attachment points, and completion status
 used by `RTT::create` and framebuffer bind/restore paths, also live in

src/renderer_gl/opengl_capabilities.cpp

@@ -475,6 +475,18 @@ std::uint32_t framebuffer_blit_filter(bool linear) noexcept
     return linear ? gl_linear : gl_nearest;
 }
 
+OpenGlEnumMapping blit_filter_for_renderer_filter(pp::renderer::BlitFilter filter) noexcept
+{
+    switch (filter) {
+    case pp::renderer::BlitFilter::nearest:
+        return OpenGlEnumMapping { .value = gl_nearest, .supported = true };
+    case pp::renderer::BlitFilter::linear:
+        return OpenGlEnumMapping { .value = gl_linear, .supported = true };
+    default:
+        return OpenGlEnumMapping {};
+    }
+}
+
 std::uint32_t primitive_mode_for_renderer_topology(pp::renderer::PrimitiveTopology topology) noexcept
 {
     switch (topology) {

src/renderer_gl/opengl_capabilities.h

@@ -100,6 +100,8 @@ struct OpenGlWindowsWglContextConfig {
 [[nodiscard]] std::uint32_t framebuffer_depth_buffer_mask() noexcept;
 [[nodiscard]] std::uint32_t color_write_mask_query() noexcept;
 [[nodiscard]] std::uint32_t framebuffer_blit_filter(bool linear) noexcept;
+[[nodiscard]] OpenGlEnumMapping blit_filter_for_renderer_filter(
+    pp::renderer::BlitFilter filter) noexcept;
 [[nodiscard]] std::uint32_t primitive_mode_for_renderer_topology(
     pp::renderer::PrimitiveTopology topology) noexcept;
 [[nodiscard]] std::uint32_t index_type_for_index_size(std::uint32_t index_size_bytes) noexcept;

tests/renderer_gl/capabilities_tests.cpp

@@ -251,11 +251,22 @@ void maps_framebuffer_render_target_parameters(pp::tests::Harness& h)
 
 void maps_framebuffer_blit_parameters(pp::tests::Harness& h)
 {
+    const auto nearest = pp::renderer::gl::blit_filter_for_renderer_filter(pp::renderer::BlitFilter::nearest);
+    const auto linear = pp::renderer::gl::blit_filter_for_renderer_filter(pp::renderer::BlitFilter::linear);
+    const auto invalid = pp::renderer::gl::blit_filter_for_renderer_filter(
+        static_cast<pp::renderer::BlitFilter>(255U));
+
     PP_EXPECT(h, pp::renderer::gl::framebuffer_color_buffer_mask() == 0x00004000U);
     PP_EXPECT(h, pp::renderer::gl::framebuffer_depth_buffer_mask() == 0x00000100U);
     PP_EXPECT(h, pp::renderer::gl::color_write_mask_query() == 0x0C23U);
     PP_EXPECT(h, pp::renderer::gl::framebuffer_blit_filter(true) == 0x2601U);
     PP_EXPECT(h, pp::renderer::gl::framebuffer_blit_filter(false) == 0x2600U);
+    PP_EXPECT(h, nearest.supported);
+    PP_EXPECT(h, nearest.value == 0x2600U);
+    PP_EXPECT(h, linear.supported);
+    PP_EXPECT(h, linear.value == 0x2601U);
+    PP_EXPECT(h, !invalid.supported);
+    PP_EXPECT(h, invalid.value == 0U);
 }
 
 void maps_renderer_primitive_topologies_to_draw_modes(pp::tests::Harness& h)