Add pdsg (palladium spirv-generator)

- remove glslang from pd-system
- use spirv blobs instead of glsl 460
- Use Legacy shaders for OpenGL2 backend
- add devnotes

tools/pdsg/CMakeLists.txt

@@ -0,0 +1,29 @@
+cmake_minimum_required(VERSION 3.22)
+
+project(pdsg LANGUAGES CXX VERSION 1.0.0)
+
+### Requires C++ 20
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED true)
+
+add_executable(pdsg
+    ${CMAKE_CURRENT_SOURCE_DIR}/source/main.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/source/spirv-helper.cpp
+)
+target_include_directories(pdsg PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}/include
+)
+target_link_libraries(pdsg PRIVATE
+    glslang
+    glslang-default-resource-limits
+    OSDependent
+    SPIRV
+
+    spirv-cross-core
+    spirv-cross-cpp
+    spirv-cross-glsl
+    spirv-cross-hlsl
+    spirv-cross-msl
+    spirv-cross-reflect
+    spirv-cross-util
+)