implot.cpp

// MIT License

// Copyright (c) 2023 Evan Pezent

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

// ImPlot v0.17

/*

API BREAKING CHANGES
====================
Occasionally introducing changes that are breaking the API. We try to make the breakage minor and easy to fix.
Below is a change-log of API breaking changes only. If you are using one of the functions listed, expect to have to fix some code.
When you are not sure about a old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all implot files.
You can read releases logs https://github.com/epezent/implot/releases for more details.

- 2023/08/20 (0.17) - ImPlotFlags_NoChild was removed as child windows are no longer needed to capture scroll. You can safely remove this flag if you were using it.
- 2023/06/26 (0.15) - Various build fixes related to updates in Dear ImGui internals.
- 2022/11/25 (0.15) - Make PlotText honor ImPlotItemFlags_NoFit.
- 2022/06/19 (0.14) - The signature of ColormapScale has changed to accommodate a new ImPlotColormapScaleFlags parameter
- 2022/06/17 (0.14) - **IMPORTANT** All PlotX functions now take an ImPlotX_Flags `flags` parameter. Where applicable, it is located before the existing `offset` and `stride` parameters.
                      If you were providing offset and stride values, you will need to update your function call to include a `flags` value. If you fail to do this, you will likely see
                      unexpected results or crashes without a compiler warning since these three are all default args. We apologize for the inconvenience, but this was a necessary evil.
                    - PlotBarsH has been removed; use PlotBars + ImPlotBarsFlags_Horizontal instead
                    - PlotErrorBarsH has been removed; use PlotErrorBars + ImPlotErrorBarsFlags_Horizontal
                    - PlotHistogram/PlotHistogram2D signatures changed; `cumulative`, `density`, and `outliers` options now specified via ImPlotHistogramFlags
                    - PlotPieChart signature changed; `normalize` option now specified via ImPlotPieChartFlags
                    - PlotText signature changes; `vertical` option now specified via `ImPlotTextFlags_Vertical`
                    - `PlotVLines` and `PlotHLines` replaced with `PlotInfLines` (+ ImPlotInfLinesFlags_Horizontal )
                    - arguments of ImPlotGetter have been reversed to be consistent with other API callbacks
                    - SetupAxisScale + ImPlotScale have replaced ImPlotAxisFlags_LogScale and ImPlotAxisFlags_Time flags
                    - ImPlotFormatters should now return an int indicating the size written
                    - the signature of ImPlotGetter has been reversed so that void* user_data is the last argument and consistent with other callbacks
- 2021/10/19 (0.13) - MAJOR API OVERHAUL! See #168 and #272
                    - TRIVIAL RENAME:
                      - ImPlotLimits                              -> ImPlotRect
                      - ImPlotYAxis_                              -> ImAxis_
                      - SetPlotYAxis                              -> SetAxis
                      - BeginDragDropTarget                       -> BeginDragDropTargetPlot
                      - BeginDragDropSource                       -> BeginDragDropSourcePlot
                      - ImPlotFlags_NoMousePos                    -> ImPlotFlags_NoMouseText
                      - SetNextPlotLimits                         -> SetNextAxesLimits
                      - SetMouseTextLocation                      -> SetupMouseText
                    - SIGNATURE MODIFIED:
                      - PixelsToPlot/PlotToPixels                 -> added optional X-Axis arg
                      - GetPlotMousePos                           -> added optional X-Axis arg
                      - GetPlotLimits                             -> added optional X-Axis arg
                      - GetPlotSelection                          -> added optional X-Axis arg
                      - DragLineX/Y/DragPoint                     -> now takes int id; removed labels (render with Annotation/Tag instead)
                    - REPLACED:
                      - IsPlotXAxisHovered/IsPlotXYAxisHovered    -> IsAxisHovered(ImAxis)
                      - BeginDragDropTargetX/BeginDragDropTargetY -> BeginDragDropTargetAxis(ImAxis)
                      - BeginDragDropSourceX/BeginDragDropSourceY -> BeginDragDropSourceAxis(ImAxis)
                      - ImPlotCol_XAxis, ImPlotCol_YAxis1, etc.   -> ImPlotCol_AxisText (push/pop this around SetupAxis to style individual axes)
                      - ImPlotCol_XAxisGrid, ImPlotCol_Y1AxisGrid -> ImPlotCol_AxisGrid (push/pop this around SetupAxis to style individual axes)
                      - SetNextPlotLimitsX/Y                      -> SetNextAxisLimits(ImAxis)
                      - LinkNextPlotLimits                        -> SetNextAxisLinks(ImAxis)
                      - FitNextPlotAxes                           -> SetNextAxisToFit(ImAxis)/SetNextAxesToFit
                      - SetLegendLocation                         -> SetupLegend
                      - ImPlotFlags_NoHighlight                   -> ImPlotLegendFlags_NoHighlight
                      - ImPlotOrientation                         -> ImPlotLegendFlags_Horizontal
                      - Annotate                                  -> Annotation
                    - REMOVED:
                      - GetPlotQuery, SetPlotQuery, IsPlotQueried -> use DragRect
                      - SetNextPlotTicksX, SetNextPlotTicksY      -> use SetupAxisTicks
                      - SetNextPlotFormatX, SetNextPlotFormatY    -> use SetupAxisFormat
                      - AnnotateClamped                           -> use Annotation(bool clamp = true)
                    - OBSOLETED:
                      - BeginPlot (original signature)            -> use simplified signature + Setup API
- 2021/07/30 (0.12) - The offset argument of `PlotXG` functions was been removed. Implement offsetting in your getter callback instead.
- 2021/03/08 (0.9)  - SetColormap and PushColormap(ImVec4*) were removed. Use AddColormap for custom colormap support. LerpColormap was changed to SampleColormap.
                      ShowColormapScale was changed to ColormapScale and requires additional arguments.
- 2021/03/07 (0.9)  - The signature of ShowColormapScale was modified to accept a ImVec2 size.
- 2021/02/28 (0.9)  - BeginLegendDragDropSource was changed to BeginDragDropSourceItem with a number of other drag and drop improvements.
- 2021/01/18 (0.9)  - The default behavior for opening context menus was change from double right-click to single right-click. ImPlotInputMap and related functions were moved
                      to implot_internal.h due to its immaturity.
- 2020/10/16 (0.8)  - ImPlotStyleVar_InfoPadding was changed to ImPlotStyleVar_MousePosPadding
- 2020/09/10 (0.8)  - The single array versions of PlotLine, PlotScatter, PlotStems, and PlotShaded were given additional arguments for x-scale and x0.
- 2020/09/07 (0.8)  - Plotting functions which accept a custom getter function pointer have been post-fixed with a G (e.g. PlotLineG)
- 2020/09/06 (0.7)  - Several flags under ImPlotFlags and ImPlotAxisFlags were inverted (e.g. ImPlotFlags_Legend -> ImPlotFlags_NoLegend) so that the default flagset
                      is simply 0. This more closely matches ImGui's style and makes it easier to enable non-default but commonly used flags (e.g. ImPlotAxisFlags_Time).
- 2020/08/28 (0.5)  - ImPlotMarker_ can no longer be combined with bitwise OR, |. This features caused unecessary slow-down, and almost no one used it.
- 2020/08/25 (0.5)  - ImPlotAxisFlags_Scientific was removed. Logarithmic axes automatically uses scientific notation.
- 2020/08/17 (0.5)  - PlotText was changed so that text is centered horizontally and vertically about the desired point.
- 2020/08/16 (0.5)  - An ImPlotContext must be explicitly created and destroyed now with `CreateContext` and `DestroyContext`. Previously, the context was statically initialized in this source file.
- 2020/06/13 (0.4)  - The flags `ImPlotAxisFlag_Adaptive` and `ImPlotFlags_Cull` were removed. Both are now done internally by default.
- 2020/06/03 (0.3)  - The signature and behavior of PlotPieChart was changed so that data with sum less than 1 can optionally be normalized. The label format can now be specified as well.
- 2020/06/01 (0.3)  - SetPalette was changed to `SetColormap` for consistency with other plotting libraries. `RestorePalette` was removed. Use `SetColormap(ImPlotColormap_Default)`.
- 2020/05/31 (0.3)  - Plot functions taking custom ImVec2* getters were removed. Use the ImPlotPoint* getter versions instead.
- 2020/05/29 (0.3)  - The signature of ImPlotLimits::Contains was changed to take two doubles instead of ImVec2
- 2020/05/16 (0.2)  - All plotting functions were reverted to being prefixed with "Plot" to maintain a consistent VerbNoun style. `Plot` was split into `PlotLine`
                      and `PlotScatter` (however, `PlotLine` can still be used to plot scatter points as `Plot` did before.). `Bar` is not `PlotBars`, to indicate
                      that multiple bars will be plotted.
- 2020/05/13 (0.2)  - `ImMarker` was change to `ImPlotMarker` and `ImAxisFlags` was changed to `ImPlotAxisFlags`.
- 2020/05/11 (0.2)  - `ImPlotFlags_Selection` was changed to `ImPlotFlags_BoxSelect`
- 2020/05/11 (0.2)  - The namespace ImGui:: was replaced with ImPlot::. As a result, the following additional changes were made:
                      - Functions that were prefixed or decorated with the word "Plot" have been truncated. E.g., `ImGui::PlotBars` is now just `ImPlot::Bar`.
                        It should be fairly obvious what was what.
                      - Some functions have been given names that would have otherwise collided with the ImGui namespace. This has been done to maintain a consistent
                        style with ImGui. E.g., 'ImGui::PushPlotStyleVar` is now 'ImPlot::PushStyleVar'.
- 2020/05/10 (0.2)  - The following function/struct names were changes:
                     - ImPlotRange       -> ImPlotLimits
                     - GetPlotRange()    -> GetPlotLimits()
                     - SetNextPlotRange  -> SetNextPlotLimits
                     - SetNextPlotRangeX -> SetNextPlotLimitsX
                     - SetNextPlotRangeY -> SetNextPlotLimitsY
- 2020/05/10 (0.2)  - Plot queries are pixel based by default. Query rects that maintain relative plot position have been removed. This was done to support multi-y-axis.

*/

#define IMGUI_DEFINE_MATH_OPERATORS
#include "implot.h"
#include "implot_internal.h"

#include <stdlib.h>

// Support for pre-1.82 versions. Users on 1.82+ can use 0 (default) flags to mean "all corners" but in order to support older versions we are more explicit.
#if (IMGUI_VERSION_NUM < 18102) && !defined(ImDrawFlags_RoundCornersAll)
#define ImDrawFlags_RoundCornersAll ImDrawCornerFlags_All
#endif

// Support for pre-1.89.7 versions.
#if (IMGUI_VERSION_NUM < 18966)
#define ImGuiButtonFlags_AllowOverlap ImGuiButtonFlags_AllowItemOverlap
#endif

// Visual Studio warnings
#ifdef _MSC_VER
#pragma warning (disable: 4996) // 'This function or variable may be unsafe': strcpy, strdup, sprintf, vsnprintf, sscanf, fopen
#endif

// Clang/GCC warnings with -Weverything
#if defined(__clang__)
#pragma clang diagnostic ignored "-Wformat-nonliteral"  // warning: format string is not a string literal
#elif defined(__GNUC__)
#pragma GCC diagnostic ignored "-Wformat-nonliteral"    // warning: format not a string literal, format string not checked
#endif

// Global plot context
#ifndef GImPlot
ImPlotContext* GImPlot = nullptr;
#endif

//-----------------------------------------------------------------------------
// Struct Implementations
//-----------------------------------------------------------------------------

ImPlotInputMap::ImPlotInputMap() {
    ImPlot::MapInputDefault(this);
}

ImPlotStyle::ImPlotStyle() {

    LineWeight         = 1;
    Marker             = ImPlotMarker_None;
    MarkerSize         = 4;
    MarkerWeight       = 1;
    FillAlpha          = 1;
    ErrorBarSize       = 5;
    ErrorBarWeight     = 1.5f;
    DigitalBitHeight   = 8;
    DigitalBitGap      = 4;

    PlotBorderSize     = 1;
    MinorAlpha         = 0.25f;
    MajorTickLen       = ImVec2(10,10);
    MinorTickLen       = ImVec2(5,5);
    MajorTickSize      = ImVec2(1,1);
    MinorTickSize      = ImVec2(1,1);
    MajorGridSize      = ImVec2(1,1);
    MinorGridSize      = ImVec2(1,1);
    PlotPadding        = ImVec2(10,10);
    LabelPadding       = ImVec2(5,5);
    LegendPadding      = ImVec2(10,10);
    LegendInnerPadding = ImVec2(5,5);
    LegendSpacing      = ImVec2(5,0);
    MousePosPadding    = ImVec2(10,10);
    AnnotationPadding  = ImVec2(2,2);
    FitPadding         = ImVec2(0,0);
    PlotDefaultSize    = ImVec2(400,300);
    PlotMinSize        = ImVec2(200,150);

    ImPlot::StyleColorsAuto(this);

    Colormap = ImPlotColormap_Deep;

    UseLocalTime     = false;
    Use24HourClock   = false;
    UseISO8601       = false;
}

//-----------------------------------------------------------------------------
// Style
//-----------------------------------------------------------------------------

namespace ImPlot {

const char* GetStyleColorName(ImPlotCol col) {
    static const char* col_names[ImPlotCol_COUNT] = {
        "Line",
        "Fill",
        "MarkerOutline",
        "MarkerFill",
        "ErrorBar",
        "FrameBg",
        "PlotBg",
        "PlotBorder",
        "LegendBg",
        "LegendBorder",
        "LegendText",
        "TitleText",
        "InlayText",
        "AxisText",
        "AxisGrid",
        "AxisTick",
        "AxisBg",
        "AxisBgHovered",
        "AxisBgActive",
        "Selection",
        "Crosshairs"
    };
    return col_names[col];
}

const char* GetMarkerName(ImPlotMarker marker) {
    switch (marker) {
        case ImPlotMarker_None:     return "None";
        case ImPlotMarker_Circle:   return "Circle";
        case ImPlotMarker_Square:   return "Square";
        case ImPlotMarker_Diamond:  return "Diamond";
        case ImPlotMarker_Up:       return "Up";
        case ImPlotMarker_Down:     return "Down";
        case ImPlotMarker_Left:     return "Left";
        case ImPlotMarker_Right:    return "Right";
        case ImPlotMarker_Cross:    return "Cross";
        case ImPlotMarker_Plus:     return "Plus";
        case ImPlotMarker_Asterisk: return "Asterisk";
        default:                    return "";
    }
}

ImVec4 GetAutoColor(ImPlotCol idx) {
    ImVec4 col(0,0,0,1);
    switch(idx) {
        case ImPlotCol_Line:          return col; // these are plot dependent!
        case ImPlotCol_Fill:          return col; // these are plot dependent!
        case ImPlotCol_MarkerOutline: return col; // these are plot dependent!
        case ImPlotCol_MarkerFill:    return col; // these are plot dependent!
        case ImPlotCol_ErrorBar:      return ImGui::GetStyleColorVec4(ImGuiCol_Text);
        case ImPlotCol_FrameBg:       return ImGui::GetStyleColorVec4(ImGuiCol_FrameBg);
        case ImPlotCol_PlotBg:        return ImGui::GetStyleColorVec4(ImGuiCol_WindowBg);
        case ImPlotCol_PlotBorder:    return ImGui::GetStyleColorVec4(ImGuiCol_Border);
        case ImPlotCol_LegendBg:      return ImGui::GetStyleColorVec4(ImGuiCol_PopupBg);
        case ImPlotCol_LegendBorder:  return GetStyleColorVec4(ImPlotCol_PlotBorder);
        case ImPlotCol_LegendText:    return GetStyleColorVec4(ImPlotCol_InlayText);
        case ImPlotCol_TitleText:     return ImGui::GetStyleColorVec4(ImGuiCol_Text);
        case ImPlotCol_InlayText:     return ImGui::GetStyleColorVec4(ImGuiCol_Text);
        case ImPlotCol_AxisText:      return ImGui::GetStyleColorVec4(ImGuiCol_Text);
        case ImPlotCol_AxisGrid:      return GetStyleColorVec4(ImPlotCol_AxisText) * ImVec4(1,1,1,0.25f);
        case ImPlotCol_AxisTick:      return GetStyleColorVec4(ImPlotCol_AxisGrid);
        case ImPlotCol_AxisBg:        return ImVec4(0,0,0,0);
        case ImPlotCol_AxisBgHovered: return ImGui::GetStyleColorVec4(ImGuiCol_ButtonHovered);
        case ImPlotCol_AxisBgActive:  return ImGui::GetStyleColorVec4(ImGuiCol_ButtonActive);
        case ImPlotCol_Selection:     return ImVec4(1,1,0,1);
        case ImPlotCol_Crosshairs:    return GetStyleColorVec4(ImPlotCol_PlotBorder);
        default: return col;
    }
}

struct ImPlotStyleVarInfo {
    ImGuiDataType   Type;
    ImU32           Count;
    ImU32           Offset;
    void*           GetVarPtr(ImPlotStyle* style) const { return (void*)((unsigned char*)style + Offset); }
};

static const ImPlotStyleVarInfo GPlotStyleVarInfo[] =
{
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, LineWeight)         }, // ImPlotStyleVar_LineWeight
    { ImGuiDataType_S32,   1, (ImU32)offsetof(ImPlotStyle, Marker)             }, // ImPlotStyleVar_Marker
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, MarkerSize)         }, // ImPlotStyleVar_MarkerSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, MarkerWeight)       }, // ImPlotStyleVar_MarkerWeight
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, FillAlpha)          }, // ImPlotStyleVar_FillAlpha
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, ErrorBarSize)       }, // ImPlotStyleVar_ErrorBarSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, ErrorBarWeight)     }, // ImPlotStyleVar_ErrorBarWeight
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, DigitalBitHeight)   }, // ImPlotStyleVar_DigitalBitHeight
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, DigitalBitGap)      }, // ImPlotStyleVar_DigitalBitGap

    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, PlotBorderSize)     }, // ImPlotStyleVar_PlotBorderSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImPlotStyle, MinorAlpha)         }, // ImPlotStyleVar_MinorAlpha
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MajorTickLen)       }, // ImPlotStyleVar_MajorTickLen
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MinorTickLen)       }, // ImPlotStyleVar_MinorTickLen
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MajorTickSize)      }, // ImPlotStyleVar_MajorTickSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MinorTickSize)      }, // ImPlotStyleVar_MinorTickSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MajorGridSize)      }, // ImPlotStyleVar_MajorGridSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MinorGridSize)      }, // ImPlotStyleVar_MinorGridSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, PlotPadding)        }, // ImPlotStyleVar_PlotPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, LabelPadding)       }, // ImPlotStyleVar_LabelPaddine
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, LegendPadding)      }, // ImPlotStyleVar_LegendPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, LegendInnerPadding) }, // ImPlotStyleVar_LegendInnerPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, LegendSpacing)      }, // ImPlotStyleVar_LegendSpacing

    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, MousePosPadding)    }, // ImPlotStyleVar_MousePosPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, AnnotationPadding)  }, // ImPlotStyleVar_AnnotationPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, FitPadding)         }, // ImPlotStyleVar_FitPadding
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, PlotDefaultSize)    }, // ImPlotStyleVar_PlotDefaultSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImPlotStyle, PlotMinSize)        }  // ImPlotStyleVar_PlotMinSize
};

static const ImPlotStyleVarInfo* GetPlotStyleVarInfo(ImPlotStyleVar idx) {
    IM_ASSERT(idx >= 0 && idx < ImPlotStyleVar_COUNT);
    IM_ASSERT(IM_ARRAYSIZE(GPlotStyleVarInfo) == ImPlotStyleVar_COUNT);
    return &GPlotStyleVarInfo[idx];
}

//-----------------------------------------------------------------------------
// Generic Helpers
//-----------------------------------------------------------------------------

void AddTextVertical(ImDrawList *DrawList, ImVec2 pos, ImU32 col, const char *text_begin, const char* text_end) {
    // the code below is based loosely on ImFont::RenderText
    if (!text_end)
        text_end = text_begin + strlen(text_begin);
    ImGuiContext& g = *GImGui;
    ImFont* font = g.Font;
    // Align to be pixel perfect
    pos.x = ImFloor(pos.x);
    pos.y = ImFloor(pos.y);
    const float scale = g.FontSize / font->FontSize;
    const char* s = text_begin;
    int chars_exp = (int)(text_end - s);
    int chars_rnd = 0;
    const int vtx_count_max = chars_exp * 4;
    const int idx_count_max = chars_exp * 6;
    DrawList->PrimReserve(idx_count_max, vtx_count_max);
    while (s < text_end) {
        unsigned int c = (unsigned int)*s;
        if (c < 0x80) {
            s += 1;
        }
        else {
            s += ImTextCharFromUtf8(&c, s, text_end);
            if (c == 0) // Malformed UTF-8?
                break;
        }
        const ImFontGlyph * glyph = font->FindGlyph((ImWchar)c);
        if (glyph == nullptr) {
            continue;
        }
        DrawList->PrimQuadUV(pos + ImVec2(glyph->Y0, -glyph->X0) * scale, pos + ImVec2(glyph->Y0, -glyph->X1) * scale,
                             pos + ImVec2(glyph->Y1, -glyph->X1) * scale, pos + ImVec2(glyph->Y1, -glyph->X0) * scale,
                             ImVec2(glyph->U0, glyph->V0), ImVec2(glyph->U1, glyph->V0),
                             ImVec2(glyph->U1, glyph->V1), ImVec2(glyph->U0, glyph->V1),
                             col);
        pos.y -= glyph->AdvanceX * scale;
        chars_rnd++;
    }
    // Give back unused vertices
    int chars_skp = chars_exp-chars_rnd;
    DrawList->PrimUnreserve(chars_skp*6, chars_skp*4);
}

void AddTextCentered(ImDrawList* DrawList, ImVec2 top_center, ImU32 col, const char* text_begin, const char* text_end) {
    float txt_ht = ImGui::GetTextLineHeight();
    const char* title_end = ImGui::FindRenderedTextEnd(text_begin, text_end);
    ImVec2 text_size;
    float  y = 0;
    while (const char* tmp = (const char*)memchr(text_begin, '\n', title_end-text_begin)) {
        text_size = ImGui::CalcTextSize(text_begin,tmp,true);
        DrawList->AddText(ImVec2(top_center.x - text_size.x * 0.5f, top_center.y+y),col,text_begin,tmp);
        text_begin = tmp + 1;
        y += txt_ht;
    }
    text_size = ImGui::CalcTextSize(text_begin,title_end,true);
    DrawList->AddText(ImVec2(top_center.x - text_size.x * 0.5f, top_center.y+y),col,text_begin,title_end);
}

double NiceNum(double x, bool round) {
    double f;
    double nf;
    int expv = (int)floor(ImLog10(x));
    f = x / ImPow(10.0, (double)expv);
    if (round)
        if (f < 1.5)
            nf = 1;
        else if (f < 3)
            nf = 2;
        else if (f < 7)
            nf = 5;
        else
            nf = 10;
    else if (f <= 1)
        nf = 1;
    else if (f <= 2)
        nf = 2;
    else if (f <= 5)
        nf = 5;
    else
        nf = 10;
    return nf * ImPow(10.0, expv);
}

//-----------------------------------------------------------------------------
// Context Utils
//-----------------------------------------------------------------------------

void SetImGuiContext(ImGuiContext* ctx) {
    ImGui::SetCurrentContext(ctx);
}

ImPlotContext* CreateContext() {
    ImPlotContext* ctx = IM_NEW(ImPlotContext)();
    Initialize(ctx);
    if (GImPlot == nullptr)
        SetCurrentContext(ctx);
    return ctx;
}

void DestroyContext(ImPlotContext* ctx) {
    if (ctx == nullptr)
        ctx = GImPlot;
    if (GImPlot == ctx)
        SetCurrentContext(nullptr);
    IM_DELETE(ctx);
}

ImPlotContext* GetCurrentContext() {
    return GImPlot;
}

void SetCurrentContext(ImPlotContext* ctx) {
    GImPlot = ctx;
}

#define IMPLOT_APPEND_CMAP(name, qual) ctx->ColormapData.Append(#name, name, sizeof(name)/sizeof(ImU32), qual)
#define IM_RGB(r,g,b) IM_COL32(r,g,b,255)

void Initialize(ImPlotContext* ctx) {
    ResetCtxForNextPlot(ctx);
    ResetCtxForNextAlignedPlots(ctx);
    ResetCtxForNextSubplot(ctx);

    const ImU32 Deep[]     = {4289753676, 4283598045, 4285048917, 4283584196, 4289950337, 4284512403, 4291005402, 4287401100, 4285839820, 4291671396                        };
    const ImU32 Dark[]     = {4280031972, 4290281015, 4283084621, 4288892568, 4278222847, 4281597951, 4280833702, 4290740727, 4288256409                                    };
    const ImU32 Pastel[]   = {4289639675, 4293119411, 4291161036, 4293184478, 4289124862, 4291624959, 4290631909, 4293712637, 4294111986                                    };
    const ImU32 Paired[]   = {4293119554, 4290017311, 4287291314, 4281114675, 4288256763, 4280031971, 4285513725, 4278222847, 4292260554, 4288298346, 4288282623, 4280834481};
    const ImU32 Viridis[]  = {4283695428, 4285867080, 4287054913, 4287455029, 4287526954, 4287402273, 4286883874, 4285579076, 4283552122, 4280737725, 4280674301            };
    const ImU32 Plasma[]   = {4287039501, 4288480321, 4289200234, 4288941455, 4287638193, 4286072780, 4284638433, 4283139314, 4281771772, 4280667900, 4280416752            };
    const ImU32 Hot[]      = {4278190144, 4278190208, 4278190271, 4278190335, 4278206719, 4278223103, 4278239231, 4278255615, 4283826175, 4289396735, 4294967295            };
    const ImU32 Cool[]     = {4294967040, 4294960666, 4294954035, 4294947661, 4294941030, 4294934656, 4294928025, 4294921651, 4294915020, 4294908646, 4294902015            };
    const ImU32 Pink[]     = {4278190154, 4282532475, 4284308894, 4285690554, 4286879686, 4287870160, 4288794330, 4289651940, 4291685869, 4293392118, 4294967295            };
    const ImU32 Jet[]      = {4289331200, 4294901760, 4294923520, 4294945280, 4294967040, 4289396565, 4283826090, 4278255615, 4278233855, 4278212095, 4278190335            };
    const ImU32 Twilight[] = {IM_RGB(226,217,226),IM_RGB(166,191,202),IM_RGB(109,144,192),IM_RGB(95,88,176),IM_RGB(83,30,124),IM_RGB(47,20,54),IM_RGB(100,25,75),IM_RGB(159,60,80),IM_RGB(192,117,94),IM_RGB(208,179,158),IM_RGB(226,217,226)};
    const ImU32 RdBu[]     = {IM_RGB(103,0,31),IM_RGB(178,24,43),IM_RGB(214,96,77),IM_RGB(244,165,130),IM_RGB(253,219,199),IM_RGB(247,247,247),IM_RGB(209,229,240),IM_RGB(146,197,222),IM_RGB(67,147,195),IM_RGB(33,102,172),IM_RGB(5,48,97)};
    const ImU32 BrBG[]     = {IM_RGB(84,48,5),IM_RGB(140,81,10),IM_RGB(191,129,45),IM_RGB(223,194,125),IM_RGB(246,232,195),IM_RGB(245,245,245),IM_RGB(199,234,229),IM_RGB(128,205,193),IM_RGB(53,151,143),IM_RGB(1,102,94),IM_RGB(0,60,48)};
    const ImU32 PiYG[]     = {IM_RGB(142,1,82),IM_RGB(197,27,125),IM_RGB(222,119,174),IM_RGB(241,182,218),IM_RGB(253,224,239),IM_RGB(247,247,247),IM_RGB(230,245,208),IM_RGB(184,225,134),IM_RGB(127,188,65),IM_RGB(77,146,33),IM_RGB(39,100,25)};
    const ImU32 Spectral[] = {IM_RGB(158,1,66),IM_RGB(213,62,79),IM_RGB(244,109,67),IM_RGB(253,174,97),IM_RGB(254,224,139),IM_RGB(255,255,191),IM_RGB(230,245,152),IM_RGB(171,221,164),IM_RGB(102,194,165),IM_RGB(50,136,189),IM_RGB(94,79,162)};
    const ImU32 Greys[]    = {IM_COL32_WHITE, IM_COL32_BLACK                                                                                                                };

    IMPLOT_APPEND_CMAP(Deep, true);
    IMPLOT_APPEND_CMAP(Dark, true);
    IMPLOT_APPEND_CMAP(Pastel, true);
    IMPLOT_APPEND_CMAP(Paired, true);
    IMPLOT_APPEND_CMAP(Viridis, false);
    IMPLOT_APPEND_CMAP(Plasma, false);
    IMPLOT_APPEND_CMAP(Hot, false);
    IMPLOT_APPEND_CMAP(Cool, false);
    IMPLOT_APPEND_CMAP(Pink, false);
    IMPLOT_APPEND_CMAP(Jet, false);
    IMPLOT_APPEND_CMAP(Twilight, false);
    IMPLOT_APPEND_CMAP(RdBu, false);
    IMPLOT_APPEND_CMAP(BrBG, false);
    IMPLOT_APPEND_CMAP(PiYG, false);
    IMPLOT_APPEND_CMAP(Spectral, false);
    IMPLOT_APPEND_CMAP(Greys, false);
}

void ResetCtxForNextPlot(ImPlotContext* ctx) {
    // reset the next plot/item data
    ctx->NextPlotData.Reset();
    ctx->NextItemData.Reset();
    // reset labels
    ctx->Annotations.Reset();
    ctx->Tags.Reset();
    // reset extents/fit
    ctx->OpenContextThisFrame = false;
    // reset digital plot items count
    ctx->DigitalPlotItemCnt = 0;
    ctx->DigitalPlotOffset = 0;
    // nullify plot
    ctx->CurrentPlot  = nullptr;
    ctx->CurrentItem  = nullptr;
    ctx->PreviousItem = nullptr;
}

void ResetCtxForNextAlignedPlots(ImPlotContext* ctx) {
    ctx->CurrentAlignmentH = nullptr;
    ctx->CurrentAlignmentV = nullptr;
}

void ResetCtxForNextSubplot(ImPlotContext* ctx) {
    ctx->CurrentSubplot      = nullptr;
    ctx->CurrentAlignmentH   = nullptr;
    ctx->CurrentAlignmentV   = nullptr;
}

//-----------------------------------------------------------------------------
// Plot Utils
//-----------------------------------------------------------------------------

ImPlotPlot* GetPlot(const char* title) {
    ImGuiWindow*   Window = GImGui->CurrentWindow;
    const ImGuiID  ID     = Window->GetID(title);
    return GImPlot->Plots.GetByKey(ID);
}

ImPlotPlot* GetCurrentPlot() {
    return GImPlot->CurrentPlot;
}

void BustPlotCache() {
    ImPlotContext& gp = *GImPlot;
    gp.Plots.Clear();
    gp.Subplots.Clear();
}

//-----------------------------------------------------------------------------
// Legend Utils
//-----------------------------------------------------------------------------

ImVec2 GetLocationPos(const ImRect& outer_rect, const ImVec2& inner_size, ImPlotLocation loc, const ImVec2& pad) {
    ImVec2 pos;
    if (ImHasFlag(loc, ImPlotLocation_West) && !ImHasFlag(loc, ImPlotLocation_East))
        pos.x = outer_rect.Min.x + pad.x;
    else if (!ImHasFlag(loc, ImPlotLocation_West) && ImHasFlag(loc, ImPlotLocation_East))
        pos.x = outer_rect.Max.x - pad.x - inner_size.x;
    else
        pos.x = outer_rect.GetCenter().x - inner_size.x * 0.5f;
    // legend reference point y
    if (ImHasFlag(loc, ImPlotLocation_North) && !ImHasFlag(loc, ImPlotLocation_South))
        pos.y = outer_rect.Min.y + pad.y;
    else if (!ImHasFlag(loc, ImPlotLocation_North) && ImHasFlag(loc, ImPlotLocation_South))
        pos.y = outer_rect.Max.y - pad.y - inner_size.y;
    else
        pos.y = outer_rect.GetCenter().y - inner_size.y * 0.5f;
    pos.x = IM_ROUND(pos.x);
    pos.y = IM_ROUND(pos.y);
    return pos;
}

ImVec2 CalcLegendSize(ImPlotItemGroup& items, const ImVec2& pad, const ImVec2& spacing, bool vertical) {
    // vars
    const int   nItems      = items.GetLegendCount();
    const float txt_ht      = ImGui::GetTextLineHeight();
    const float icon_size   = txt_ht;
    // get label max width
    float max_label_width = 0;
    float sum_label_width = 0;
    for (int i = 0; i < nItems; ++i) {
        const char* label       = items.GetLegendLabel(i);
        const float label_width = ImGui::CalcTextSize(label, nullptr, true).x;
        max_label_width         = label_width > max_label_width ? label_width : max_label_width;
        sum_label_width        += label_width;
    }
    // calc legend size
    const ImVec2 legend_size = vertical ?
                               ImVec2(pad.x * 2 + icon_size + max_label_width, pad.y * 2 + nItems * txt_ht + (nItems - 1) * spacing.y) :
                               ImVec2(pad.x * 2 + icon_size * nItems + sum_label_width + (nItems - 1) * spacing.x, pad.y * 2 + txt_ht);
    return legend_size;
}

bool ClampLegendRect(ImRect& legend_rect, const ImRect& outer_rect, const ImVec2& pad) {
    bool clamped = false;
    ImRect outer_rect_pad(outer_rect.Min + pad, outer_rect.Max - pad);
    if (legend_rect.Min.x < outer_rect_pad.Min.x) {
        legend_rect.Min.x = outer_rect_pad.Min.x;
        clamped = true;
    }
    if (legend_rect.Min.y < outer_rect_pad.Min.y) {
        legend_rect.Min.y = outer_rect_pad.Min.y;
        clamped = true;
    }
    if (legend_rect.Max.x > outer_rect_pad.Max.x) {
        legend_rect.Max.x = outer_rect_pad.Max.x;
        clamped = true;
    }
    if (legend_rect.Max.y > outer_rect_pad.Max.y) {
        legend_rect.Max.y = outer_rect_pad.Max.y;
        clamped = true;
    }
    return clamped;
}

int LegendSortingComp(const void* _a, const void* _b) {
    ImPlotItemGroup* items = GImPlot->SortItems;
    const int a = *(const int*)_a;
    const int b = *(const int*)_b;
    const char* label_a = items->GetLegendLabel(a);
    const char* label_b = items->GetLegendLabel(b);
    return strcmp(label_a,label_b);
}

bool ShowLegendEntries(ImPlotItemGroup& items, const ImRect& legend_bb, bool hovered, const ImVec2& pad, const ImVec2& spacing, bool vertical, ImDrawList& DrawList) {
    // vars
    const float txt_ht      = ImGui::GetTextLineHeight();
    const float icon_size   = txt_ht;
    const float icon_shrink = 2;
    ImU32 col_txt           = GetStyleColorU32(ImPlotCol_LegendText);
    ImU32 col_txt_dis       = ImAlphaU32(col_txt, 0.25f);
    // render each legend item
    float sum_label_width = 0;
    bool any_item_hovered = false;

    const int num_items = items.GetLegendCount();
    if (num_items < 1)
        return hovered;
    // build render order
    ImPlotContext& gp = *GImPlot;
    ImVector<int>& indices = gp.TempInt1;
    indices.resize(num_items);
    for (int i = 0; i < num_items; ++i)
        indices[i] = i;
    if (ImHasFlag(items.Legend.Flags, ImPlotLegendFlags_Sort) && num_items > 1) {
        gp.SortItems = &items;
        qsort(indices.Data, num_items, sizeof(int), LegendSortingComp);
    }
    // render
    for (int i = 0; i < num_items; ++i) {
        const int idx           = indices[i];
        ImPlotItem* item        = items.GetLegendItem(idx);
        const char* label       = items.GetLegendLabel(idx);
        const float label_width = ImGui::CalcTextSize(label, nullptr, true).x;
        const ImVec2 top_left   = vertical ?
                                  legend_bb.Min + pad + ImVec2(0, i * (txt_ht + spacing.y)) :
                                  legend_bb.Min + pad + ImVec2(i * (icon_size + spacing.x) + sum_label_width, 0);
        sum_label_width        += label_width;
        ImRect icon_bb;
        icon_bb.Min = top_left + ImVec2(icon_shrink,icon_shrink);
        icon_bb.Max = top_left + ImVec2(icon_size - icon_shrink, icon_size - icon_shrink);
        ImRect label_bb;
        label_bb.Min = top_left;
        label_bb.Max = top_left + ImVec2(label_width + icon_size, icon_size);
        ImU32 col_txt_hl;
        ImU32 col_item = ImAlphaU32(item->Color,1);

        ImRect button_bb(icon_bb.Min, label_bb.Max);

        ImGui::KeepAliveID(item->ID);

        bool item_hov = false;
        bool item_hld = false;
        bool item_clk = ImHasFlag(items.Legend.Flags, ImPlotLegendFlags_NoButtons)
                      ? false
                      : ImGui::ButtonBehavior(button_bb, item->ID, &item_hov, &item_hld);

        if (item_clk)
            item->Show = !item->Show;


        const bool can_hover = (item_hov)
                             && (!ImHasFlag(items.Legend.Flags, ImPlotLegendFlags_NoHighlightItem)
                             || !ImHasFlag(items.Legend.Flags, ImPlotLegendFlags_NoHighlightAxis));

        if (can_hover) {
            item->LegendHoverRect.Min = icon_bb.Min;
            item->LegendHoverRect.Max = label_bb.Max;
            item->LegendHovered = true;
            col_txt_hl = ImMixU32(col_txt, col_item, 64);
            any_item_hovered = true;
        }
        else {
            col_txt_hl = ImGui::GetColorU32(col_txt);
        }
        ImU32 col_icon;
        if (item_hld)
            col_icon = item->Show ? ImAlphaU32(col_item,0.5f) : ImGui::GetColorU32(ImGuiCol_TextDisabled, 0.5f);
        else if (item_hov)
            col_icon = item->Show ? ImAlphaU32(col_item,0.75f) : ImGui::GetColorU32(ImGuiCol_TextDisabled, 0.75f);
        else
            col_icon = item->Show ? col_item : col_txt_dis;

        DrawList.AddRectFilled(icon_bb.Min, icon_bb.Max, col_icon);
        const char* text_display_end = ImGui::FindRenderedTextEnd(label, nullptr);
        if (label != text_display_end)
            DrawList.AddText(top_left + ImVec2(icon_size, 0), item->Show ? col_txt_hl  : col_txt_dis, label, text_display_end);
    }
    return hovered && !any_item_hovered;
}

//-----------------------------------------------------------------------------
// Locators
//-----------------------------------------------------------------------------

static const float TICK_FILL_X = 0.8f;
static const float TICK_FILL_Y = 1.0f;

void Locator_Default(ImPlotTicker& ticker, const ImPlotRange& range, float pixels, bool vertical, ImPlotFormatter formatter, void* formatter_data) {
    if (range.Min == range.Max)
        return;
    const int nMinor        = 10;
    const int nMajor        = ImMax(2, (int)IM_ROUND(pixels / (vertical ? 300.0f : 400.0f)));
    const double nice_range = NiceNum(range.Size() * 0.99, false);
    const double interval   = NiceNum(nice_range / (nMajor - 1), true);
    const double graphmin   = floor(range.Min / interval) * interval;
    const double graphmax   = ceil(range.Max / interval) * interval;
    bool first_major_set    = false;
    int  first_major_idx    = 0;
    const int idx0 = ticker.TickCount(); // ticker may have user custom ticks
    ImVec2 total_size(0,0);
    for (double major = graphmin; major < graphmax + 0.5 * interval; major += interval) {
        // is this zero? combat zero formatting issues
        if (major-interval < 0 && major+interval > 0)
            major = 0;
        if (range.Contains(major)) {
            if (!first_major_set) {
                first_major_idx = ticker.TickCount();
                first_major_set = true;
            }
            total_size += ticker.AddTick(major, true, 0, true, formatter, formatter_data).LabelSize;
        }
        for (int i = 1; i < nMinor; ++i) {
            double minor = major + i * interval / nMinor;
            if (range.Contains(minor)) {
                total_size += ticker.AddTick(minor, false, 0, true, formatter, formatter_data).LabelSize;
            }
        }
    }
    // prune if necessary
    if ((!vertical && total_size.x > pixels*TICK_FILL_X) || (vertical && total_size.y > pixels*TICK_FILL_Y)) {
        for (int i = first_major_idx-1; i >= idx0; i -= 2)
            ticker.Ticks[i].ShowLabel = false;
        for (int i = first_major_idx+1; i < ticker.TickCount(); i += 2)
            ticker.Ticks[i].ShowLabel = false;
    }
}

bool CalcLogarithmicExponents(const ImPlotRange& range, float pix, bool vertical, int& exp_min, int& exp_max, int& exp_step) {
    if (range.Min * range.Max > 0) {
        const int nMajor = vertical ? ImMax(2, (int)IM_ROUND(pix * 0.02f)) : ImMax(2, (int)IM_ROUND(pix * 0.01f)); // TODO: magic numbers
        double log_min = ImLog10(ImAbs(range.Min));
        double log_max = ImLog10(ImAbs(range.Max));
        double log_a = ImMin(log_min,log_max);
        double log_b = ImMax(log_min,log_max);
        exp_step  = ImMax(1,(int)(log_b - log_a) / nMajor);
        exp_min   = (int)log_a;
        exp_max   = (int)log_b;
        if (exp_step != 1) {
            while(exp_step % 3 != 0)       exp_step++; // make step size multiple of three
            while(exp_min % exp_step != 0) exp_min--;  // decrease exp_min until exp_min + N * exp_step will be 0
        }
        return true;
    }
    return false;
}

void AddTicksLogarithmic(const ImPlotRange& range, int exp_min, int exp_max, int exp_step, ImPlotTicker& ticker, ImPlotFormatter formatter, void* data) {
    const double sign = ImSign(range.Max);
    for (int e = exp_min - exp_step; e < (exp_max + exp_step); e += exp_step) {
        double major1 = sign*ImPow(10, (double)(e));
        double major2 = sign*ImPow(10, (double)(e + 1));
        double interval = (major2 - major1) / 9;
        if (major1 >= (range.Min - DBL_EPSILON) && major1 <= (range.Max + DBL_EPSILON))
            ticker.AddTick(major1, true, 0, true, formatter, data);
        for (int j = 0; j < exp_step; ++j) {
            major1 = sign*ImPow(10, (double)(e+j));
            major2 = sign*ImPow(10, (double)(e+j+1));
            interval = (major2 - major1) / 9;
            for (int i = 1; i < (9 + (int)(j < (exp_step - 1))); ++i) {
                double minor = major1 + i * interval;
                if (minor >= (range.Min - DBL_EPSILON) && minor <= (range.Max + DBL_EPSILON))
                    ticker.AddTick(minor, false, 0, false, formatter, data);
            }
        }
    }
}

void Locator_Log10(ImPlotTicker& ticker, const ImPlotRange& range, float pixels, bool vertical, ImPlotFormatter formatter, void* formatter_data) {
    int exp_min, exp_max, exp_step;
    if (CalcLogarithmicExponents(range, pixels, vertical, exp_min, exp_max, exp_step))
        AddTicksLogarithmic(range, exp_min, exp_max, exp_step, ticker, formatter, formatter_data);
}

float CalcSymLogPixel(double plt, const ImPlotRange& range, float pixels) {
    double scaleToPixels = pixels / range.Size();
    double scaleMin      = TransformForward_SymLog(range.Min,nullptr);
    double scaleMax      = TransformForward_SymLog(range.Max,nullptr);
    double s             = TransformForward_SymLog(plt, nullptr);
    double t             = (s - scaleMin) / (scaleMax - scaleMin);
    plt                  = range.Min + range.Size() * t;

    return (float)(0 + scaleToPixels * (plt - range.Min));
}

void Locator_SymLog(ImPlotTicker& ticker, const ImPlotRange& range, float pixels, bool vertical, ImPlotFormatter formatter, void* formatter_data) {
    if (range.Min >= -1 && range.Max <= 1) {
        Locator_Default(ticker, range, pixels, vertical, formatter, formatter_data);
    }
    else if (range.Min * range.Max < 0) { // cross zero
        const float pix_min = 0;
        const float pix_max = pixels;
        const float pix_p1  = CalcSymLogPixel(1, range, pixels);
        const float pix_n1  = CalcSymLogPixel(-1, range, pixels);
        int exp_min_p, exp_max_p, exp_step_p;
        int exp_min_n, exp_max_n, exp_step_n;
        CalcLogarithmicExponents(ImPlotRange(1,range.Max), ImAbs(pix_max-pix_p1),vertical,exp_min_p,exp_max_p,exp_step_p);
        CalcLogarithmicExponents(ImPlotRange(range.Min,-1),ImAbs(pix_n1-pix_min),vertical,exp_min_n,exp_max_n,exp_step_n);
        int exp_step = ImMax(exp_step_n, exp_step_p);
        ticker.AddTick(0,true,0,true,formatter,formatter_data);
        AddTicksLogarithmic(ImPlotRange(1,range.Max), exp_min_p,exp_max_p,exp_step,ticker,formatter,formatter_data);
        AddTicksLogarithmic(ImPlotRange(range.Min,-1),exp_min_n,exp_max_n,exp_step,ticker,formatter,formatter_data);
    }
    else {
        Locator_Log10(ticker, range, pixels, vertical, formatter, formatter_data);
    }
}

void AddTicksCustom(const double* values, const char* const labels[], int n, ImPlotTicker& ticker, ImPlotFormatter formatter, void* data) {
    for (int i = 0; i < n; ++i) {
        if (labels != nullptr)
            ticker.AddTick(values[i], false, 0, true, labels[i]);
        else
            ticker.AddTick(values[i], false, 0, true, formatter, data);
    }
}

//-----------------------------------------------------------------------------
// Time Ticks and Utils
//-----------------------------------------------------------------------------

// this may not be thread safe?
static const double TimeUnitSpans[ImPlotTimeUnit_COUNT] = {
    0.000001,
    0.001,
    1,
    60,
    3600,
    86400,
    2629800,
    31557600
};

inline ImPlotTimeUnit GetUnitForRange(double range) {
    static double cutoffs[ImPlotTimeUnit_COUNT] = {0.001, 1, 60, 3600, 86400, 2629800, 31557600, IMPLOT_MAX_TIME};
    for (int i = 0; i < ImPlotTimeUnit_COUNT; ++i) {
        if (range <= cutoffs[i])
            return (ImPlotTimeUnit)i;
    }
    return ImPlotTimeUnit_Yr;
}

inline int LowerBoundStep(int max_divs, const int* divs, const int* step, int size) {
    if (max_divs < divs[0])
        return 0;
    for (int i = 1; i < size; ++i) {
        if (max_divs < divs[i])
            return step[i-1];
    }
    return step[size-1];
}

inline int GetTimeStep(int max_divs, ImPlotTimeUnit unit) {
    if (unit == ImPlotTimeUnit_Ms || unit == ImPlotTimeUnit_Us) {
        static const int step[] = {500,250,200,100,50,25,20,10,5,2,1};
        static const int divs[] = {2,4,5,10,20,40,50,100,200,500,1000};
        return LowerBoundStep(max_divs, divs, step, 11);
    }
    if (unit == ImPlotTimeUnit_S || unit == ImPlotTimeUnit_Min) {
        static const int step[] = {30,15,10,5,1};
        static const int divs[] = {2,4,6,12,60};
        return LowerBoundStep(max_divs, divs, step, 5);
    }
    else if (unit == ImPlotTimeUnit_Hr) {
        static const int step[] = {12,6,3,2,1};
        static const int divs[] = {2,4,8,12,24};
        return LowerBoundStep(max_divs, divs, step, 5);
    }
    else if (unit == ImPlotTimeUnit_Day) {
        static const int step[] = {14,7,2,1};
        static const int divs[] = {2,4,14,28};
        return LowerBoundStep(max_divs, divs, step, 4);
    }
    else if (unit == ImPlotTimeUnit_Mo) {
        static const int step[] = {6,3,2,1};
        static const int divs[] = {2,4,6,12};
        return LowerBoundStep(max_divs, divs, step, 4);
    }
    return 0;
}

ImPlotTime MkGmtTime(struct tm *ptm) {
    ImPlotTime t;
#ifdef _WIN32
    t.S = _mkgmtime(ptm);
#else
    t.S = timegm(ptm);
#endif
    if (t.S < 0)
        t.S = 0;
    return t;
}

tm* GetGmtTime(const ImPlotTime& t, tm* ptm)
{
#ifdef _WIN32
  if (gmtime_s(ptm, &t.S) == 0)
    return ptm;
  else
    return nullptr;
#else
  return gmtime_r(&t.S, ptm);
#endif
}

ImPlotTime MkLocTime(struct tm *ptm) {
    ImPlotTime t;
    t.S = mktime(ptm);
    if (t.S < 0)
        t.S = 0;
    return t;
}

tm* GetLocTime(const ImPlotTime& t, tm* ptm) {
#ifdef _WIN32
  if (localtime_s(ptm, &t.S) == 0)
    return ptm;
  else
    return nullptr;
#else
    return localtime_r(&t.S, ptm);
#endif
}

inline ImPlotTime MkTime(struct tm *ptm) {
    if (GetStyle().UseLocalTime)
        return MkLocTime(ptm);
    else
        return MkGmtTime(ptm);
}

inline tm* GetTime(const ImPlotTime& t, tm* ptm) {
    if (GetStyle().UseLocalTime)
        return GetLocTime(t,ptm);
    else
        return GetGmtTime(t,ptm);
}

ImPlotTime MakeTime(int year, int month, int day, int hour, int min, int sec, int us) {
    tm& Tm = GImPlot->Tm;

    int yr = year - 1900;
    if (yr < 0)
        yr = 0;

    sec  = sec + us / 1000000;
    us   = us % 1000000;

    Tm.tm_sec  = sec;
    Tm.tm_min  = min;
    Tm.tm_hour = hour;
    Tm.tm_mday = day;
    Tm.tm_mon  = month;
    Tm.tm_year = yr;

    ImPlotTime t = MkTime(&Tm);

    t.Us = us;
    return t;
}

int GetYear(const ImPlotTime& t) {
    tm& Tm = GImPlot->Tm;
    GetTime(t, &Tm);
    return Tm.tm_year + 1900;
}

ImPlotTime AddTime(const ImPlotTime& t, ImPlotTimeUnit unit, int count) {
    tm& Tm = GImPlot->Tm;
    ImPlotTime t_out = t;
    switch(unit) {
        case ImPlotTimeUnit_Us:  t_out.Us += count;         break;
        case ImPlotTimeUnit_Ms:  t_out.Us += count * 1000;  break;
        case ImPlotTimeUnit_S:   t_out.S  += count;         break;
        case ImPlotTimeUnit_Min: t_out.S  += count * 60;    break;