imgui_toggle_math.h

#pragma once

#include "imgui.h"

#ifndef IMGUI_DEFINE_MATH_OPERATORS
#define IMGUI_DEFINE_MATH_OPERATORS
#endif // IMGUI_DEFINE_MATH_OPERATORS
#include "imgui_internal.h"

namespace ImGuiToggleMath
{
    // lerp, but backwards!
    template<typename T> constexpr inline T ImInvLerp(T a, T b, float value) { return (T)((value - a) / (b - a)); }

    // float comparison w/tolerance - can't constexper as ImFabs isn't constexpr.
    inline bool ImApproximately(float a, float b, float tolerance = 0.0001f) { return ImAbs(a - b) < tolerance; }

    // helpers for checking if an ImVec4 is zero or not.
    constexpr inline bool IsZero(const ImVec4& v) { return v.w == 0 && v.x == 0 && v.y == 0 && v.z == 0; }
    constexpr inline bool IsNonZero(const ImVec4& v) { return v.w != 0 || v.x != 0 || v.y != 0 || v.z != 0; }
} // namespace