Windows additions

core/sys/windows/types.odin

@@ -39,6 +39,7 @@ HKEY :: distinct HANDLE
 HDESK :: distinct HANDLE
 HFONT :: distinct HANDLE
 HRGN :: distinct HANDLE
+HDWP :: distinct HANDLE
 BOOL :: distinct b32
 BYTE :: distinct u8
 BOOLEAN :: distinct b8
@@ -297,6 +298,14 @@ REASON_CONTEXT :: struct {
 }
 PREASON_CONTEXT :: ^REASON_CONTEXT
 
+BLENDFUNCTION :: struct {
+  BlendOp: BYTE,
+  BlendFlags: BYTE,
+  SourceConstantAlpha: BYTE,
+  AlphaFormat: BYTE,
+}
+PBLENDFUNCTION :: ^BLENDFUNCTION
+
 // RRF - Registry Routine Flags (for RegGetValue)
 RRF_RT_REG_NONE      :: 0x00000001
 RRF_RT_REG_SZ        :: 0x00000002
@@ -700,6 +709,8 @@ WNDPROC :: #type proc "stdcall" (HWND, UINT, WPARAM, LPARAM) -> LRESULT
 
 HOOKPROC :: #type proc "stdcall" (code: c_int, wParam: WPARAM, lParam: LPARAM) -> LRESULT
 
+SENDASYNCPROC :: #type proc "stdcall" (HWND, UINT, ULONG_PTR, LRESULT)
+
 CWPRETSTRUCT :: struct {
 	lResult: LRESULT,
 	lParam: LPARAM,