BeamNG ImGui Cheat Sheet

local im = ui_imgui
local ffi = require("ffi")

im.Begin("Title")                           -- Basic window
im.Begin("Title", boolPtr)                  -- With close button (X)
im.Begin("Title", nil, flags)               -- With flags
im.End()                                    -- ALWAYS call (even if Begin=false)

im.BeginChild1("id", size, border)          -- Scrollable sub-region
im.EndChild()

im.Text("Hello %s", name)                   -- Formatted text
im.TextColored(im.ImVec4(r,g,b,a), "text")  -- Colored
im.TextWrapped("Long text...")               -- Word-wrapped
im.TextDisabled("Greyed out")                -- Dimmed
im.BulletText("List item")                   -- Bulleted
im.SeparatorText("Section")                  -- Text with separator line
im.LabelText("Label", "Value")              -- Label: Value aligned

im.Button("Click", im.ImVec2(w, h))         -- Returns true on click
im.SmallButton("small")                      -- Compact button
im.ArrowButton("id", im.Dir_Right)           -- Arrow button
im.InvisibleButton("id", im.ImVec2(w, h))   -- Clickable area, no visual

-- Numeric
im.InputInt("Label", intPtr, step, fastStep)
im.InputFloat("Label", floatPtr, step, fastStep, "%.2f")
im.InputDouble("Label", doublePtr, step, fastStep, "%.5f")

-- Sliders
im.SliderInt("Label", intPtr, min, max)
im.SliderFloat("Label", floatPtr, min, max, "%.1f")
im.SliderAngle("Angle", floatPtr, min, max)
im.VSliderFloat("Label", im.ImVec2(w,h), floatPtr, min, max)

-- Drag (click+drag to change)
im.DragFloat("Label", floatPtr, speed, min, max)
im.DragInt("Label", intPtr, speed, min, max)

-- Text
im.InputText("Label", arrayChar, bufSize)
im.InputText("Label", buf, 256, im.InputTextFlags_EnterReturnsTrue)
im.InputTextMultiline("Label", buf, bufSize, im.ImVec2(w, h))
im.InputTextWithHint("Label", "placeholder...", buf, bufSize)

-- Bool
im.Checkbox("Label", boolPtr)

-- Radio
im.RadioButton2("A", intPtr, im.Int(0))
im.RadioButton2("B", intPtr, im.Int(1))

-- Combo (dropdown)
if im.BeginCombo("Label", previewText) then
  for i, item in ipairs(items) do
    if im.Selectable1(item, i == selected) then selected = i end
  end
  im.EndCombo()
end

-- Selectable (list item)
im.Selectable1("Item", isSelected)

-- Color
im.ColorEdit3("Color", floatArray3)
im.ColorEdit4("Color", floatArray4)
im.ColorPicker4("Picker", floatArray4)

im.SameLine()                                -- Next widget on same line
im.Spacing()                                 -- Small vertical space
im.Separator()                               -- Horizontal line
im.NewLine()                                 -- Force new line
im.Indent()                                  -- Increase indent
im.Unindent()                                -- Decrease indent
im.Dummy(im.ImVec2(w, h))                   -- Invisible spacer

im.SetNextItemWidth(200)                     -- Width of next widget
im.PushItemWidth(200)                        -- Width of all widgets until Pop
im.PopItemWidth()

im.BeginGroup()                              -- Group widgets (for layout)
im.EndGroup()

im.GetContentRegionAvail()                   -- Available space (.x, .y)
im.GetCursorPos()                            -- Current cursor position
im.SetCursorPosX(x)                          -- Set horizontal position

-- Collapsible header
if im.CollapsingHeader1("Section") then ... end

-- Tree node
if im.TreeNode1("Node") then
  im.Text("Child")
  im.TreePop()  -- REQUIRED
end

-- Tab bar
if im.BeginTabBar("tabs") then
  if im.BeginTabItem("Tab 1") then ... im.EndTabItem() end
  if im.BeginTabItem("Tab 2") then ... im.EndTabItem() end
  im.EndTabBar()
end

-- Table
if im.BeginTable("id", numColumns, flags) then
  im.TableSetupColumn("Col1")
  im.TableHeadersRow()
  im.TableNextRow()
  im.TableSetColumnIndex(0)
  im.Text("cell")
  im.EndTable()
end

im.OpenPopup("id")                           -- Open popup
if im.BeginPopup("id") then ... im.EndPopup() end
if im.BeginPopupModal("id") then ... im.EndPopup() end
im.CloseCurrentPopup()

-- Context menu (right-click)
if im.BeginPopupContextItem("id") then ... im.EndPopup() end

-- In a window with WindowFlags_MenuBar
if im.BeginMenuBar() then
  if im.BeginMenu("File") then
    if im.MenuItem1("Save") then ... end
    im.EndMenu()
  end
  im.EndMenuBar()
end

-- Colors (push/pop)
im.PushStyleColor2(im.Col_Text, im.ImVec4(r,g,b,a))
-- ... widgets ...
im.PopStyleColor(count)

-- Variables (push/pop)
im.PushStyleVar1(im.StyleVar_WindowBorderSize, 0)
im.PushStyleVar2(im.StyleVar_WindowPadding, im.ImVec2(10, 10))
-- ... widgets ...
im.PopStyleVar(count)

-- Disable widgets
im.BeginDisabled(true)
-- ... greyed out widgets ...
im.EndDisabled()

im.IsItemHovered()                           -- Mouse over last widget?
im.IsItemClicked()                           -- Clicked last widget?
im.IsItemActive()                            -- Holding/interacting?
im.IsItemEdited()                            -- Value changed?
im.IsItemDeactivatedAfterEdit()              -- Released after editing?
im.IsItemVisible()                           -- In visible area?
im.IsWindowFocused()                         -- Window has focus?
im.IsWindowHovered()                         -- Mouse over window?
im.IsAnyItemActive()                         -- Any widget active?
im.IsMouseClicked(0)                         -- Left mouse clicked? (0=left,1=right)
im.IsMouseDoubleClicked(0)
im.GetMousePos()                             -- Mouse position (.x, .y)

im.PushID1("string_id")                     -- String-based ID scope
im.PushID4(intId)                            -- Int-based ID scope
im.PopID()

-- Or use ## in labels:
im.Button("Click##unique1")
im.Button("Click##unique2")

-- MUST use TableToArrayFloat + GetLengthArrayFloat (not raw tables or ffi cdata)
local data = im.TableToArrayFloat({10, 20, 30, 40, 50})
im.PlotLines1("##plot", data, im.GetLengthArrayFloat(data), 0, "overlay", 0, 100, im.ImVec2(200, 80))
im.PlotHistogram1("##hist", data, im.GetLengthArrayFloat(data), 0, "overlay", 0, 100, im.ImVec2(200, 80))

local dl = im.GetWindowDrawList()
local c = im.GetColorU322(im.ImVec4(r,g,b,a))

im.ImDrawList_AddLine(dl, p1, p2, c, thickness)
im.ImDrawList_AddRect(dl, p1, p2, c, rounding, flags, thickness)
im.ImDrawList_AddRectFilled(dl, p1, p2, c, rounding, flags)
im.ImDrawList_AddCircle(dl, center, radius, c, segments, thickness)
im.ImDrawList_AddCircleFilled(dl, center, radius, c, segments)
im.ImDrawList_AddTriangleFilled(dl, p1, p2, p3, c)
im.ImDrawList_AddText1(dl, pos, c, text)

-- Fixed utility window
im.WindowFlags_AlwaysAutoResize + im.WindowFlags_NoCollapse + im.WindowFlags_NoResize

-- Overlay (no interaction)
im.WindowFlags_NoTitleBar + im.WindowFlags_NoResize + im.WindowFlags_NoMove + im.WindowFlags_NoInputs + im.WindowFlags_NoBackground

-- Full editor window
im.WindowFlags_MenuBar

-- Borderless child
im.BeginChild1("id", size, false, im.WindowFlags_NoScrollbar)