Added imgui and an option to inject source files into dependant projects.

recipes/imgui/recipe.py

@@ -0,0 +1,30 @@
+from SCons.Script import *
+
+import os
+
+def cook(env: Environment, backends: list = [], git_ref: str = '') -> dict:
+    repo = env.Cook('GitBranch', repo_name = 'imgui', remote_url = 'https://github.com/ocornut/imgui.git', git_ref = git_ref or 'master')
+
+    imgui_source_files = [
+        os.path.join(repo['checkout_root'], 'imgui.cpp'),
+        os.path.join(repo['checkout_root'], 'imgui_draw.cpp'),
+        os.path.join(repo['checkout_root'], 'imgui_tables.cpp'),
+        os.path.join(repo['checkout_root'], 'imgui_widgets.cpp')
+    ]
+
+    imgui_add_sources = []
+    backend_sources = {
+        'vulkan': os.path.join(repo['checkout_root'], 'backends/imgui_impl_vulkan.cpp'),
+        'sdl2': os.path.join(repo['checkout_root'], 'backends/imgui_impl_sdl2.cpp')
+    }
+    for backend in backends:
+        imgui_add_sources.append(backend_sources[backend])
+
+    lib_imgui = env.StaticLibrary(
+        CPPPATH = [repo['checkout_root']],
+        CPPDEFINES = ['IMGUI_IMPL_VULKAN_NO_PROTOTYPES=1'],
+        target = env['LIB_DIR'] + '/imgui',
+        source = imgui_source_files,
+        add_source = imgui_add_sources
+    )
+    return lib_imgui