Method GetCustomRectByIndex

tutorials/common/imgui/imgui.h:2801–2801

    IMGUI_API int               AddCustomRectRegular(int width, int height);
    IMGUI_API int               AddCustomRectFontGlyph(ImFont* font, ImWchar id, int width, int height, float advance_x, const ImVec2& offset = ImVec2(0, 0));
    ImFontAtlasCustomRect*      GetCustomRectByIndex(int index) { IM_ASSERT(index >= 0); return &CustomRects[index]; }

    // [Internal]
    IMGUI_API void              CalcCustomRectUV(const ImFontAtlasCustomRect* rect, ImVec2* out_uv_min, ImVec2* out_uv_max) const;