Internal: Added ImVec4 operators

imgui_internal.h

diff --git a/imgui_internal.h b/imgui_internal.h
index 131c158..8978ed7 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -127,7 +127,9 @@
 static inline ImVec2& operator-=(ImVec2& lhs, const ImVec2& rhs)                { lhs.x -= rhs.x; lhs.y -= rhs.y; return lhs; }
 static inline ImVec2& operator*=(ImVec2& lhs, const float rhs)                  { lhs.x *= rhs; lhs.y *= rhs; return lhs; }
 static inline ImVec2& operator/=(ImVec2& lhs, const float rhs)                  { lhs.x /= rhs; lhs.y /= rhs; return lhs; }
+static inline ImVec4 operator+(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x+rhs.x, lhs.y+rhs.y, lhs.z+rhs.z, lhs.w+rhs.w); }
 static inline ImVec4 operator-(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x-rhs.x, lhs.y-rhs.y, lhs.z-rhs.z, lhs.w-rhs.w); }
+static inline ImVec4 operator*(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x*rhs.x, lhs.y*rhs.y, lhs.z*rhs.z, lhs.w*rhs.w); }
 #endif
 
 static inline int    ImMin(int lhs, int rhs)                                    { return lhs < rhs ? lhs : rhs; }