Internals: Added ImDot(), ImRotate(), ImLerp(v2,v2,float) helpers.

imgui_internal.h

@@ -134,12 +134,15 @@ static inline ImVec2 ImClamp(const ImVec2& f, const ImVec2& mn, ImVec2 mx)
 static inline float  ImSaturate(float f)                                        { return (f < 0.0f) ? 0.0f : (f > 1.0f) ? 1.0f : f; }
 static inline int    ImLerp(int a, int b, float t)                              { return (int)(a + (b - a) * t); }
 static inline float  ImLerp(float a, float b, float t)                          { return a + (b - a) * t; }
+static inline ImVec2 ImLerp(const ImVec2& a, const ImVec2& b, float t)          { return ImVec2(a.x + (b.x - a.x) * t, a.y + (b.y - a.y) * t); }
 static inline ImVec2 ImLerp(const ImVec2& a, const ImVec2& b, const ImVec2& t)  { return ImVec2(a.x + (b.x - a.x) * t.x, a.y + (b.y - a.y) * t.y); }
 static inline float  ImLengthSqr(const ImVec2& lhs)                             { return lhs.x*lhs.x + lhs.y*lhs.y; }
 static inline float  ImLengthSqr(const ImVec4& lhs)                             { return lhs.x*lhs.x + lhs.y*lhs.y + lhs.z*lhs.z + lhs.w*lhs.w; }
 static inline float  ImInvLength(const ImVec2& lhs, float fail_value)           { float d = lhs.x*lhs.x + lhs.y*lhs.y; if (d > 0.0f) return 1.0f / sqrtf(d); return fail_value; }
 static inline float  ImFloor(float f)                                           { return (float)(int)f; }
-static inline ImVec2 ImFloor(ImVec2 v)                                          { return ImVec2((float)(int)v.x, (float)(int)v.y); }
+static inline ImVec2 ImFloor(const ImVec2& v)                                   { return ImVec2((float)(int)v.x, (float)(int)v.y); }
+static inline float  ImDot(const ImVec2& a, const ImVec2& b)                    { return a.x * b.x + a.y * b.y; }
+static inline ImVec2 ImRotate(const ImVec2& v, float cos_a, float sin_a)        { return ImVec2(v.x * cos_a - v.y * sin_a, v.x * sin_a + v.y * cos_a); }
 
 // We call C++ constructor on own allocated memory via the placement "new(ptr) Type()" syntax.
 // Defining a custom placement new() with a dummy parameter allows us to bypass including <new> which on some platforms complains when user has disabled exceptions.