More windowing changes for renderdoc

src/Engine/Graphics/slang-compile.cpp

@@ -1,6 +1,7 @@
 #include "slang-compile.h"
 #include "Containers/Array.h"
 #include "Graphics/Descriptor.h"
+#include <filesystem>
 #include <fmt/core.h>
 #include <iostream>
 #include <slang.h>
@@ -27,9 +28,56 @@ thread_local Slang::ComPtr<slang::IComponentType> specializedComponent;
 thread_local Slang::ComPtr<slang::ISession> session;
 thread_local Array<std::string> entryPoints;
 
+namespace {
+std::filesystem::path getExecutableDirectory() {
+    std::error_code error;
+    auto exePath = std::filesystem::read_symlink("/proc/self/exe", error);
+    if (!error) {
+        return exePath.parent_path();
+    }
+    return std::filesystem::current_path();
+}
+
+std::filesystem::path findExistingDirectory(std::initializer_list<std::filesystem::path> candidates) {
+    for (const auto& candidate : candidates) {
+        std::error_code error;
+        if (std::filesystem::exists(candidate, error) && std::filesystem::is_directory(candidate, error)) {
+            return candidate;
+        }
+    }
+    return {};
+}
+
+void configureDownstreamCompilers(slang::IGlobalSession* session) {
+    const auto executableDirectory = getExecutableDirectory();
+    const auto currentDirectory = std::filesystem::current_path();
+    const auto glslangDirectory = findExistingDirectory({
+        executableDirectory / "Seele",
+        executableDirectory / "vcpkg_installed" / "x64-linux" / "lib",
+        currentDirectory / "Seele",
+        currentDirectory / "vcpkg_installed" / "x64-linux" / "lib",
+    });
+
+    if (!glslangDirectory.empty()) {
+        const std::string path = glslangDirectory.string();
+        session->setDownstreamCompilerPath(SLANG_PASS_THROUGH_GLSLANG, path.c_str());
+        session->setDownstreamCompilerPath(SLANG_PASS_THROUGH_SPIRV_OPT, path.c_str());
+        session->setDownstreamCompilerPath(SLANG_PASS_THROUGH_SPIRV_DIS, path.c_str());
+    }
+
+    // Avoid optional SPIR-V downstream tools that are often unavailable in RenderDoc launch environments.
+    session->setDefaultDownstreamCompiler(SLANG_SOURCE_LANGUAGE_SPIRV, SLANG_PASS_THROUGH_NONE);
+    session->setDownstreamCompilerForTransition(SLANG_SPIRV, SLANG_SPIRV, SLANG_PASS_THROUGH_NONE);
+    session->setDownstreamCompilerForTransition(SLANG_SPIRV, SLANG_SPIRV_ASM, SLANG_PASS_THROUGH_NONE);
+}
+}
+
 void Seele::beginCompilation(const ShaderCompilationInfo& info, SlangCompileTarget target, Gfx::PPipelineLayout layout) {
     if (!globalSession) {
-        slang::createGlobalSession(globalSession.writeRef());
+        SlangGlobalSessionDesc sessionDesc = {};
+        sessionDesc.enableGLSL = true;
+        slang::createGlobalSession(&sessionDesc, globalSession.writeRef());
+        configureDownstreamCompilers(globalSession);
     }
     slang::SessionDesc sessionDesc;
     sessionDesc.flags = 0;
@@ -42,6 +90,30 @@ void Seele::beginCompilation(const ShaderCompilationInfo& info, SlangCompileTarg
                     .intValue0 = info.dumpIntermediate,
                 },
         },
+        {
+            .name = slang::CompilerOptionName::Optimization,
+            .value =
+                {
+                    .kind = slang::CompilerOptionValueKind::Int,
+                    .intValue0 = SLANG_OPTIMIZATION_LEVEL_NONE,
+                },
+        },
+        {
+            .name = slang::CompilerOptionName::SkipSPIRVValidation,
+            .value =
+                {
+                    .kind = slang::CompilerOptionValueKind::Int,
+                    .intValue0 = 1,
+                },
+        },
+        {
+            .name = slang::CompilerOptionName::SkipDownstreamLinking,
+            .value =
+                {
+                    .kind = slang::CompilerOptionValueKind::Int,
+                    .intValue0 = 1,
+                },
+        },
     };
 
     sessionDesc.compilerOptionEntries = option.data();