axmol/extensions/ImGui

cocos2d-x-imgui

This project is ImGui binding for cocos2d-x, with most things bind to lua.

Currently it works with cocos2d-x 4.0 and ImGui docking branch. Branch v3 can work with cocos2d-x 3.x, but will not be maintained.

How to use

• Include headers.

#include "CCImGuiLayer.h"

• Add ImGui layer (usually on top).

std::string layerName = "ImGUILayer";
auto order = INT_MAX;
auto layer = ImGuiLayer::create();
Director::getInstance()->getRunningScene()->addChild(layer, order, layerName);

• Keep the layer when scene changes.

auto e = Director::getInstance()->getEventDispatcher();
auto detached = false;
e->addCustomEventListener(Director::EVENT_BEFORE_SET_NEXT_SCENE, [&](EventCustom*){
	layer = dynamic_cast<ImGuiLayer*>(Director::getInstance()->getRunningScene()->getChildByName(layerName));
	if (layer) {
		layer->retain();
		layer->removeFromParent();
		detached = true;
	}
});
e->addCustomEventListener(Director::EVENT_AFTER_SET_NEXT_SCENE, [&](EventCustom*){
	if (layer && detached) {
		Director::getInstance()->getRunningScene()->addChild(layer, order, layerName);
		layer->release();
		detached = false;
	}
});

• Use ImGui.

// enable docking
auto& io = ImGui::GetIO();
io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
auto sp = Sprite::create("filename.png");
layer->addChild(sp);
// add ui callbacks
CCIMGUI::getInstance()->addCallback([=](){
	ImGui::Text("Hello, world!");
	// create button with Sprite, auto pushID / popID with texture id
	CCIMGUI::getInstance()->imageButton(sp, ImVec2(0, 0));
}, "hello");
// remove ui callbacks to stop rendering
CCIMGUI::getInstance()->removeCallback("hello");
// add chinese font
io.Fonts->AddFontFromFileTTF("path/to/font.ttf", 16.0f, 0, io.Fonts->GetGlyphRangesChineseFull());

• Enable lua binding.

#include "lua-bindings/imgui_lua.hpp"
auto L = LuaEngine::getInstance()->getLuaStack()->getLuaState();
luaopen_imgui(L);

• Use in lua. Note that all functions are start with a lower letter. The lua_doc folder contains docs for lua, just include it to your lua IDE (docs are in EmmyLua format). The lua_src folder contains helpers and wrappers for lua development.
  • Without helper

  local ret, buf, float = nil, '', 0
  imgui.draw = function()
  	-- new window
  	if imgui.begin("Window From Lua") then
  		-- text
  		imgui.text("Hello, World!")
  		-- text button
  		imgui.button("text button")
  		-- input text
  		ret, buf = imgui.inputText("input", buf)
  		-- slider
  		ret, float = imgui.sliderFloat("float", float, 0, 8)
  		-- end window
  		imgui.endToLua()
  	end
  end
  -- check error somewhere
  if imgui.error then
  	error(imgui.error)
  end
  

  • With helper

  require('imgui.__init__')
  local wi = require('imgui.Widget')
  local im = imgui
  local la = im.on()
  local sp = cc.Sprite:create('filename.png'):setVisible(false)
  la:addChild(sp) -- retain sprite
  local flags = im.WindowFlags.HorizontalScrollbar
  local content = wi.Widget(function()
  	imgui.text("Hello, World!")
  	im.image(sp)
  end)
  la:addChild(wi.Window('Window From Lua', nil, flags)
  	:addChild(content)
  	:addChild(wi.TreeNode('Tree')
  		:addChild(wi.Text('text', cc.c3b(255, 0, 0), 'bullet'))
  		:addChild(im.sameLine)
  		:addChild(wi.Button('button'))
  		:addChild(im.separator)
  		:addChild(wi.Checkbox('checkbox'))
  	)
  )
  

Thanks

Thanks to all previous works:

• https://github.com/namkazt/cocos2d-x-ImGui
• https://github.com/Mjarkiew/cocos2dx-imgui
• https://github.com/c0i/imguix