Add required headers to compile on macos

src/drawing/batch.cpp

@@ -6,6 +6,7 @@
 #include <blah/graphics/material.h>
 #include <blah/math/calc.h>
 #include <blah/core/app.h>
+#include <cmath>
 
 using namespace Blah;
 namespace

src/graphics/material.cpp

@@ -1,5 +1,6 @@
 #include <blah/graphics/material.h>
 #include <blah/core/log.h>
+#include <cstring>
 
 using namespace Blah;
 

src/internal/platform_backend.h

@@ -114,7 +114,9 @@ namespace Blah
 		void gl_context_make_current(void* context);
 		void gl_context_destroy(void* context);
 
+#if _WIN32
 		// D3D11 Methods
 		void* d3d11_get_hwnd();
+#endif
 	}
 }

src/internal/platform_backend_sdl2.cpp

@@ -649,6 +649,7 @@ void PlatformBackend::gl_context_destroy(void* context)
 	SDL_GL_DeleteContext(context);
 }
 
+#if _WIN32
 void* PlatformBackend::d3d11_get_hwnd()
 {
 	SDL_SysWMinfo info;
@@ -656,5 +657,5 @@ void* PlatformBackend::d3d11_get_hwnd()
 	SDL_GetWindowWMInfo(window, &info);
 	return info.info.win.window;
 }
-
+#endif
 #endif // BLAH_USE_SDL2