1 files changed, 222 insertions, 0 deletions
diff --git a/src/imgui_helper_internal.cpp b/src/imgui_helper_internal.cpp
new file mode 100644
index 0000000..3267dcc
--- /dev/null
+++ b/src/imgui_helper_internal.cpp
@@ -0,0 +1,222 @@
+#include "imgui_internal_widgets.h"
+
+
+#include "imgui.h"
+#ifndef IMGUI_DEFINE_MATH_OPERATORS
+#define IMGUI_DEFINE_MATH_OPERATORS
+#endif
+#include "imgui_internal.h"
+
+// A modded version of ScalarSlider allowing for the minimum and maximum parts
+// of the slider to be draggable by two other buttons. p_mid is from range -1
+// to 1, and s_min and max are from 0-1.
+bool ImGui::SliderLevels(const char* label, const char* label2, const char* label3, void* p_mid, void* p_left, void* p_right)
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return false;
+
+    const float SliderMin = 0.1;
+    const float SliderMax = 10;
+    const float OtherMin = 0;
+    const float OtherMax = 1;
+    const void* p_min = &SliderMin;
+    const void* p_max = &SliderMax;
+    const void* o_min = &OtherMin;
+    const void* o_max = &OtherMax;
+    ImGuiDataType data_type = ImGuiDataType_Float;
+    const char *format = "%f";
+
+    ImGuiSliderFlags flags = ImGuiSliderFlags_NoInput;
+    ImGuiContext& g = *GImGui;
+    const ImGuiStyle& style = g.Style;
+
+    // I'm not well-versed in exactly what ImGui's id system does, but I'm
+    // pretty sure it's one clickable object equals one ImGui ID.
+    const ImGuiID id_L = window->GetID(label);
+    const ImGuiID id_R = window->GetID(label2);
+    const ImGuiID id_mid = window->GetID(label3);
+    const float w = CalcItemWidth();
+
+    const ImVec2 label_size = CalcTextSize(label, NULL, true);
+    const ImRect frame_bb(window->DC.CursorPos, window->DC.CursorPos + ImVec2(w, label_size.y + style.FramePadding.y * 2.0f));
+    const ImRect total_bb(frame_bb.Min, frame_bb.Max + ImVec2(label_size.x > 0.0f ? style.ItemInnerSpacing.x + label_size.x : 0.0f, 0.0f));
+
+    ItemSize(total_bb, style.FramePadding.y);
+
+    if (!ItemAdd(total_bb, id_L, &frame_bb, 0))
+        return false;
+    if (!ItemAdd(total_bb, id_R, &frame_bb, 0))
+        return false;
+    if (!ItemAdd(total_bb, id_mid, &frame_bb, 0))
+        return false;
+
+    bool any_val_changed;
+    // Slider behavior
+    ImRect grab_bb;
+    const bool value_changed = SliderBehavior(frame_bb, id_L, data_type, p_left, o_min, o_max, format, flags, &grab_bb);
+    if (value_changed) {
+        MarkItemEdited(id_L);
+        any_val_changed = true;
+    }
+
+    ImRect grab_bb2;
+    const bool value_changed2 = SliderBehavior(frame_bb, id_R, data_type, p_right, o_min, o_max, format, flags, &grab_bb2);
+    if (value_changed2) {
+        MarkItemEdited(id_R);
+        any_val_changed = true;
+    }
+
+    const ImRect mid_bb(ImVec2(grab_bb.Max.x, frame_bb.Min.y), ImVec2(grab_bb2.Min.x, frame_bb.Max.y));
+
+    // Slider behavior
+    ImRect grab_bb3;
+    const bool value_changed3 = SliderBehavior(mid_bb, id_mid, data_type, p_mid, p_min, p_max, format, flags | ImGuiSliderFlags_Logarithmic, &grab_bb3);
+    if (value_changed3) {
+        MarkItemEdited(id_mid);
+        any_val_changed = true;
+    }
+
+    const bool hovered = ItemHoverable(frame_bb, id_L);
+
+        const bool input_requested_by_tabbing =  (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_FocusedByTabbing) != 0;
+        const bool clicked = (hovered && g.IO.MouseClicked[0]);
+        const bool make_active = (input_requested_by_tabbing || clicked || g.NavActivateId == id_L || g.NavActivateInputId == id_L);
+
+        if (make_active)
+        {
+            if (g.IO.MousePos.x < grab_bb.Max.x) {
+                SetActiveID(id_L, window);
+                SetFocusID(id_L, window);
+            } else if (g.IO.MousePos.x > grab_bb2.Min.x) {
+                SetActiveID(id_R, window);
+                SetFocusID(id_R, window);
+            } else {
+                SetActiveID(id_mid, window);
+                SetFocusID(id_mid, window);
+            }
+            FocusWindow(window);
+            g.ActiveIdUsingNavDirMask |= (1 << ImGuiDir_Left) | (1 << ImGuiDir_Right);
+        }
+
+
+    // Draw frame
+    const ImU32 frame_col = GetColorU32(g.ActiveId == id_L ? ImGuiCol_FrameBgActive : hovered ? ImGuiCol_FrameBgHovered : ImGuiCol_FrameBg);
+    RenderNavHighlight(frame_bb, id_L);
+    RenderFrame(frame_bb.Min, frame_bb.Max, frame_col, true, g.Style.FrameRounding);
+
+
+    // Render grab
+    if (grab_bb.Max.x > grab_bb.Min.x)
+        window->DrawList->AddRectFilled(grab_bb.Min, grab_bb.Max, GetColorU32(g.ActiveId == id_L ? ImGuiCol_SliderGrabActive : ImGuiCol_SliderGrab), style.GrabRounding);
+
+
+    // Render grab
+    if (grab_bb2.Max.x > grab_bb2.Min.x)
+        window->DrawList->AddRectFilled(grab_bb2.Min, grab_bb2.Max, GetColorU32(g.ActiveId == id_R ? ImGuiCol_SliderGrabActive : ImGuiCol_SliderGrab), style.GrabRounding);
+
+
+    // Render grab
+    if (grab_bb3.Max.x > grab_bb3.Min.x)
+        window->DrawList->AddRectFilled(grab_bb3.Min, grab_bb3.Max, GetColorU32(g.ActiveId == id_mid ? ImGuiCol_SliderGrabActive : ImGuiCol_SliderGrab), style.GrabRounding);
+
+    // Display value using user-provided display format so user can add prefix/suffix/decorations to the value.
+    char value_buf[64];
+    const char* value_buf_end = value_buf + DataTypeFormatString(value_buf, IM_ARRAYSIZE(value_buf), data_type, p_mid, format);
+    if (g.LogEnabled)
+        LogSetNextTextDecoration("{", "}");
+    RenderTextClipped(frame_bb.Min, frame_bb.Max, value_buf, value_buf_end, NULL, ImVec2(0.5f, 0.5f));
+
+    if (label_size.x > 0.0f)
+        RenderText(ImVec2(frame_bb.Max.x + style.ItemInnerSpacing.x, frame_bb.Min.y + style.FramePadding.y), label);
+
+    IMGUI_TEST_ENGINE_ITEM_INFO(id, label, g.LastItemData.StatusFlags);
+    return any_val_changed;
+}
+
+bool ImGui::TestLine(ImVec2 p0, ImVec2 p1)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return false;
+
+    bool Toggle = false;
+
+    ImDrawList* draw_list = window->DrawList;
+    // ImGuiStyle& style = g.Style;
+
+    ImVec2 point = ImLineClosestPoint(p0, p1, g.IO.MousePos);
+
+    ImU32 col = ImGui::GetColorU32(ImGuiCol_ScrollbarGrab);
+
+    if (ImFabs(g.IO.MousePos.x - point.x) < 3 &&  ImFabs(g.IO.MousePos.y - point.y) < 3 &&
+        point.x != p0.x && point.y != p0.y &&
+        point.x != p1.x && point.y != p1.y)
+    {
+        col = ImGui::GetColorU32(ImGuiCol_Button);
+        Toggle = true;
+    }
+
+    draw_list->AddLine(p0, p1, col, 2.0f);
+
+    return Toggle;
+}
+
+// Currently not used anywhere outside of debug UI. I'll keep it in case
+// there's a place where doing this operation in UI space is useful. Note that
+// the version of this function in bezier.cpp differs in precision by about
+// 0.001.
+
+ImVec2 ImGui::RatioToPoint(ImVec2 a, ImVec2 b, float ratio)
+{
+    ImVec2 ab_dir = b - a;
+    float ab_len_sqr = ab_dir.x * ab_dir.x + ab_dir.y * ab_dir.y;
+    float dot = ratio*ab_len_sqr;
+    return a + ab_dir * dot / ab_len_sqr;
+}
+
+// Returns true when cursor is close to the curve but not too close to the
+// beginning/end points. Basically just a wrapper for that ClosestPoint
+// function.
+bool ImGui::BezierInteractive(ImVec2 p0, ImVec2 p1, ImVec2 p2, ImVec2 p3)
+{
+    bool hovered = false;
+
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return false;
+
+    ImVec2 point = ImBezierCubicClosestPointCasteljau(p0, p1, p2, p3, g.IO.MousePos, GetStyle().CurveTessellationTol);
+
+    if (ImFabs(g.IO.MousePos.x - point.x) < 3 && ImFabs(g.IO.MousePos.y - point.y) < 3 &&
+        ImFabs(p0.x - point.x) > 3 && ImFabs(p0.y - point.y) > 3 &&
+        ImFabs(p1.x - point.x) > 3 && ImFabs(p1.y - point.y) > 3)
+    {
+        hovered = true;
+    }
+
+    return hovered;
+}
+
+bool ImGui::LineInteractive(ImVec2 p0, ImVec2 p1)
+{
+    bool hovered = false;
+
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return false;
+
+    ImVec2 point = ImLineClosestPoint(p0, p1, g.IO.MousePos);
+
+    if (ImFabs(g.IO.MousePos.x - point.x) < 3 && ImFabs(g.IO.MousePos.y - point.y) < 3 &&
+        ImFabs(p0.x - point.x) > 3 && ImFabs(p0.y - point.y) > 3 &&
+        ImFabs(p1.x - point.x) > 3 && ImFabs(p1.y - point.y) > 3)
+    {
+        hovered = true;
+    }
+
+    return hovered;
+}