Add render backend capability info ABI

app/CMakeLists.txt

@@ -148,6 +148,16 @@ target_link_libraries(oakgl-cabi-check PRIVATE ${OLIVE_LIBRARIES} OfxHost)
 target_compile_definitions(oakgl-cabi-check PRIVATE ${OLIVE_DEFINITIONS})
 target_compile_options(oakgl-cabi-check PRIVATE ${OLIVE_COMPILE_OPTIONS})
 
+add_library(oakvulkan-cabi-check OBJECT
+  render/vulkan/vulkanbackend_c.cpp
+)
+target_include_directories(oakvulkan-cabi-check PRIVATE
+  ${CMAKE_SOURCE_DIR}/app
+)
+target_link_libraries(oakvulkan-cabi-check PRIVATE Qt${QT_VERSION_MAJOR}::Core)
+target_compile_definitions(oakvulkan-cabi-check PRIVATE ${OLIVE_DEFINITIONS})
+target_compile_options(oakvulkan-cabi-check PRIVATE ${OLIVE_COMPILE_OPTIONS})
+
 # Add application
 add_executable(olive-editor
   main.cpp
@@ -156,7 +166,7 @@ add_executable(olive-editor
 )
 target_include_directories(olive-editor PUBLIC pluginSupport)
 target_link_libraries(olive-editor PUBLIC OfxHost)
-add_dependencies(olive-editor oakgl-cabi-check)
+add_dependencies(olive-editor oakgl-cabi-check oakvulkan-cabi-check)
 if (OAK_ENABLE_DYNAMIC_RENDER_BACKEND)
   add_dependencies(olive-editor oakgl oakvulkan)
 endif()

app/render/backend/dynamicrenderer.cpp

@@ -142,6 +142,8 @@ bool DynamicRenderer::ResolveFunctions()
 	RESOLVE(opengl_context_, OakBackendOpenGLContextFn,
 			"oak_renderer_opengl_context");
 #undef RESOLVE
+	get_info_ = reinterpret_cast<OakBackendGetInfoFn>(
+		library_.resolve("oak_renderer_get_info"));
 	is_available_ = reinterpret_cast<OakBackendIsAvailableFn>(
 		library_.resolve("oak_renderer_is_available"));
 	return true;
@@ -165,6 +167,7 @@ void DynamicRenderer::ResetFunctions()
 {
 	create_ = nullptr;
 	destroy_ = nullptr;
+	get_info_ = nullptr;
 	is_available_ = nullptr;
 	init_ = nullptr;
 	init_with_context_ = nullptr;
@@ -184,6 +187,11 @@ void DynamicRenderer::ResetFunctions()
 	opengl_context_ = nullptr;
 }
 
+bool DynamicRenderer::GetBackendInfo(OakRenderBackendInfo *out_info) const
+{
+	return handle_ && get_info_ && out_info && get_info_(handle_, out_info);
+}
+
 bool DynamicRenderer::Init()
 {
 	return Load() && init_(handle_);

app/render/backend/dynamicrenderer.h

@@ -19,6 +19,11 @@ public:
 
 	bool Load();
 	bool InitWithOpenGLContext(QOpenGLContext *context);
+	bool GetBackendInfo(OakRenderBackendInfo *out_info) const;
+	QString backend_name() const
+	{
+		return backend_;
+	}
 
 	virtual bool Init() override;
 	virtual void PostDestroy() override;
@@ -62,6 +67,7 @@ private:
 
 	OakBackendCreateFn create_ = nullptr;
 	OakBackendDestroyFn destroy_ = nullptr;
+	OakBackendGetInfoFn get_info_ = nullptr;
 	OakBackendIsAvailableFn is_available_ = nullptr;
 	OakBackendInitFn init_ = nullptr;
 	OakBackendInitWithContextFn init_with_context_ = nullptr;

app/render/backend/renderbackend_c.h

@@ -2,6 +2,7 @@
 #define RENDERBACKEND_C_H
 
 #include <stdbool.h>
+#include <stdint.h>
 
 #ifdef _WIN32
 #define OAK_RENDER_BACKEND_EXPORT extern "C" __declspec(dllexport)
@@ -15,8 +16,32 @@ extern "C" {
 
 typedef void *OakRenderBackendHandle;
 
+enum OakRenderBackendKind {
+	OAK_RENDER_BACKEND_UNKNOWN = 0,
+	OAK_RENDER_BACKEND_OPENGL = 1,
+	OAK_RENDER_BACKEND_VULKAN = 2
+};
+
+enum OakRenderBackendCapability {
+	OAK_RENDER_BACKEND_CAP_TEXTURES = 1ULL << 0,
+	OAK_RENDER_BACKEND_CAP_SHADERS = 1ULL << 1,
+	OAK_RENDER_BACKEND_CAP_BLIT = 1ULL << 2,
+	OAK_RENDER_BACKEND_CAP_READBACK = 1ULL << 3,
+	OAK_RENDER_BACKEND_CAP_VIEWER_CONTEXT = 1ULL << 4
+};
+
+struct OakRenderBackendInfo {
+	uint32_t abi_version;
+	uint32_t kind;
+	uint64_t capabilities;
+	const char *name;
+	const char *status;
+};
+
 typedef OakRenderBackendHandle (*OakBackendCreateFn)(void *parent);
 typedef void (*OakBackendDestroyFn)(OakRenderBackendHandle handle);
+typedef bool (*OakBackendGetInfoFn)(OakRenderBackendHandle handle,
+								struct OakRenderBackendInfo *out_info);
 typedef bool (*OakBackendIsAvailableFn)(OakRenderBackendHandle handle);
 typedef bool (*OakBackendInitFn)(OakRenderBackendHandle handle);
 typedef void (*OakBackendInitWithContextFn)(OakRenderBackendHandle handle,

app/render/opengl/openglbackend_c.cpp

@@ -43,6 +43,23 @@ OAK_RENDER_BACKEND_EXPORT void oak_renderer_destroy(OakRenderBackendHandle handl
 	delete Renderer(handle);
 }
 
+OAK_RENDER_BACKEND_EXPORT bool oak_renderer_get_info(
+	OakRenderBackendHandle handle, OakRenderBackendInfo *out_info)
+{
+	if (!handle || !out_info) {
+		return false;
+	}
+	out_info->abi_version = 1;
+	out_info->kind = OAK_RENDER_BACKEND_OPENGL;
+	out_info->capabilities = OAK_RENDER_BACKEND_CAP_TEXTURES |
+		OAK_RENDER_BACKEND_CAP_SHADERS | OAK_RENDER_BACKEND_CAP_BLIT |
+		OAK_RENDER_BACKEND_CAP_READBACK |
+		OAK_RENDER_BACKEND_CAP_VIEWER_CONTEXT;
+	out_info->name = "opengl";
+	out_info->status = "available";
+	return true;
+}
+
 OAK_RENDER_BACKEND_EXPORT bool oak_renderer_is_available(
 	OakRenderBackendHandle handle)
 {

app/render/vulkan/vulkanbackend_c.cpp

@@ -38,6 +38,20 @@ OAK_RENDER_BACKEND_EXPORT void oak_renderer_destroy(OakRenderBackendHandle handl
 	delete Backend(handle);
 }
 
+OAK_RENDER_BACKEND_EXPORT bool oak_renderer_get_info(
+	OakRenderBackendHandle handle, OakRenderBackendInfo *out_info)
+{
+	if (!handle || !out_info) {
+		return false;
+	}
+	out_info->abi_version = 1;
+	out_info->kind = OAK_RENDER_BACKEND_VULKAN;
+	out_info->capabilities = 0;
+	out_info->name = "vulkan";
+	out_info->status = "placeholder-unavailable";
+	return true;
+}
+
 OAK_RENDER_BACKEND_EXPORT bool oak_renderer_is_available(
 	OakRenderBackendHandle handle)
 {

docs/zh/render-backend-dynamic-plan.md

@@ -61,6 +61,8 @@
 
 已新增可选 `oak_renderer_is_available` C ABI：后端库可以在被加载和 create 后报告自身是否可用。OpenGL 后端返回可用；Vulkan 占位后端返回不可用，适配器随后卸载它并回退 OpenGL。这把“后端存在”和“后端可用于渲染”分开，避免后续最小化链接边界时把不可用实现误接入渲染路径。
 
+已新增 `oak_renderer_get_info` C ABI：后端库可以报告 ABI 版本、后端类型、能力位和状态字符串。默认构建也会编译检查 OpenGL/Vulkan 两个 C wrapper，避免只在实验构建中发现 C ABI 破损。
+
 因此动态后端成为默认路径前，仍需要把 OpenGL 后端库的链接边界收敛到最小集合：
 
 - 后端库只拥有 OpenGL/Vulkan native 操作和必要的后端私有状态。

tests/gtest/dynamic_render_backend_test.cpp

@@ -10,6 +10,15 @@ TEST(DynamicRenderBackend, LoadsExperimentalOpenGLBackend)
 	olive::DynamicRenderer renderer(QStringLiteral("opengl"));
 	ASSERT_TRUE(renderer.Load());
 	EXPECT_EQ(renderer.OpenGLContext(), nullptr);
+	OakRenderBackendInfo info = {};
+	ASSERT_TRUE(renderer.GetBackendInfo(&info));
+	EXPECT_EQ(info.abi_version, 1U);
+	EXPECT_EQ(info.kind, OAK_RENDER_BACKEND_OPENGL);
+	EXPECT_STREQ(info.name, "opengl");
+	EXPECT_TRUE(info.capabilities & OAK_RENDER_BACKEND_CAP_TEXTURES);
+	EXPECT_TRUE(info.capabilities & OAK_RENDER_BACKEND_CAP_SHADERS);
+	EXPECT_TRUE(info.capabilities & OAK_RENDER_BACKEND_CAP_BLIT);
+	EXPECT_TRUE(info.capabilities & OAK_RENDER_BACKEND_CAP_READBACK);
 #endif
 }
 
@@ -20,6 +29,11 @@ TEST(DynamicRenderBackend, FallsBackWhenExperimentalVulkanUnavailable)
 #else
 	olive::DynamicRenderer renderer(QStringLiteral("vulkan"));
 	ASSERT_TRUE(renderer.Load());
+	EXPECT_EQ(renderer.backend_name(), QStringLiteral("opengl"));
 	EXPECT_EQ(renderer.OpenGLContext(), nullptr);
+	OakRenderBackendInfo info = {};
+	ASSERT_TRUE(renderer.GetBackendInfo(&info));
+	EXPECT_EQ(info.kind, OAK_RENDER_BACKEND_OPENGL);
+	EXPECT_STREQ(info.name, "opengl");
 #endif
 }