LOVE-IMGUI

imgui module for the LÖVE game engine including lua bindings based on this project. The main difference is that now by default in this version the return values ordering is reverted. For instance to retrieve the value from a slider, you need to do:

floatValue, status = imgui.SliderFloat("SliderFloat", floatValue, 0.0, 1.0);

Or if you're not interested to know if the field was modified, just:

floatValue = imgui.SliderFloat("SliderFloat", floatValue, 0.0, 1.0);

To reverse this behavior and receive back the return values from a function first before the modified fields, just call at the beginning of your application:

imgui.SetReturnValueLast(false)

Another notable difference is that enum values are handled using strings (and array of strings) instead of numerical values, for instance to create a window:

imgui.Begin("Test Window", true, { "ImGuiWindowFlags_AlwaysAutoResize", "ImGuiWindowFlags_NoTitleBar" });

Or for a single flag:

imgui.Begin("Test Window", true, "ImGuiWindowFlags_AlwaysAutoResize");

It uses imgui 1.73 and is based on LÖVE 11.1.

Getting Started

Build the project using CMake:

cmake -Bbuild -H. -DCMAKE_INSTALL_PREFIX=$PWD/installdir -DCMAKE_BUILD_TYPE=Release
cmake --build build --config Release --target install

(Windows users may want to change $PWD with %CD% when running from cmd)

Then copy the generated dynamic module next to your love executable or into the LÖVE application data folder (for instance "C:/Users//AppData/Roaming/LOVE" on Windows or ~/.local/shared/love on Linux).

Pre-built binaries for Windows and Mas OSX are provided in the releases page.

Examples

Simple integration

local imgui = require "imgui"

local showTestWindow = false
local showAnotherWindow = false
local floatValue = 0;
local sliderFloat = { 0.1, 0.5 }
local clearColor = { 0.2, 0.2, 0.2 }
local comboSelection = 1
local textValue = "text"

--
-- LOVE callbacks
--
function love.load(arg)
end

function love.update(dt)
    imgui.NewFrame()
end

function love.draw()

    -- Menu
    if imgui.BeginMainMenuBar() then
        if imgui.BeginMenu("File") then
            imgui.MenuItem("Test")
            imgui.EndMenu()
        end
        imgui.EndMainMenuBar()
    end

    -- Debug window
    imgui.Text("Hello, world!");
    clearColor[1], clearColor[2], clearColor[3] = imgui.ColorEdit3("Clear color", clearColor[1], clearColor[2], clearColor[3]);
    
    -- Sliders
    floatValue = imgui.SliderFloat("SliderFloat", floatValue, 0.0, 1.0);
    sliderFloat[1], sliderFloat[2] = imgui.SliderFloat2("SliderFloat2", sliderFloat[1], sliderFloat[2], 0.0, 1.0);
    
    -- Combo
    comboSelection = imgui.Combo("Combo", comboSelection, { "combo1", "combo2", "combo3", "combo4" }, 4);

    -- Windows
    if imgui.Button("Test Window") then
        showTestWindow = not showTestWindow;
    end
    
    if imgui.Button("Another Window") then
        showAnotherWindow = not showAnotherWindow;
    end
    
    if showAnotherWindow then
        imgui.SetNextWindowPos(50, 50, "ImGuiCond_FirstUseEver")
        showAnotherWindow = imgui.Begin("Another Window", true, { "ImGuiWindowFlags_AlwaysAutoResize", "ImGuiWindowFlags_NoTitleBar" });
        imgui.Text("Hello");
        -- Input text
        textValue = imgui.InputTextMultiline("InputText", textValue, 200, 300, 200);
        imgui.End();
    end

    if showTestWindow then
        showTestWindow = imgui.ShowDemoWindow(true)
    end

    love.graphics.clear(clearColor[1], clearColor[2], clearColor[3])
    imgui.Render();
end

function love.quit()
    imgui.ShutDown();
end

--
-- User inputs
--
function love.textinput(t)
    imgui.TextInput(t)
    if not imgui.GetWantCaptureKeyboard() then
        -- Pass event to the game
    end
end

function love.keypressed(key)
    imgui.KeyPressed(key)
    if not imgui.GetWantCaptureKeyboard() then
        -- Pass event to the game
    end
end

function love.keyreleased(key)
    imgui.KeyReleased(key)
    if not imgui.GetWantCaptureKeyboard() then
        -- Pass event to the game
    end
end

function love.mousemoved(x, y)
    imgui.MouseMoved(x, y)
    if not imgui.GetWantCaptureMouse() then
        -- Pass event to the game
    end
end

function love.mousepressed(x, y, button)
    imgui.MousePressed(button)
    if not imgui.GetWantCaptureMouse() then
        -- Pass event to the game
    end
end

function love.mousereleased(x, y, button)
    imgui.MouseReleased(button)
    if not imgui.GetWantCaptureMouse() then
        -- Pass event to the game
    end
end

function love.wheelmoved(x, y)
    imgui.WheelMoved(y)
    if not imgui.GetWantCaptureMouse() then
        -- Pass event to the game
    end
end

Fonts

Since ImGui::IO isn't exposed to Lua, the ImFontAtlas::AddFontFileFromTTF function is forwarded to the main API table, enabling the use of custom fonts:

local fontHandle = imgui.AddFontFileFromTTF("pathToFont.tff", 16)
imgui.PushFont(fontHandle)
imgui.Text "Hello"
imgui.PopFont()

Note that imgui.NewFrame() must be called at least once before using imgui.PushFont().

License