ImGui Interface class for forwarding all events to the original ImGui Handlers. More...

#include <SLImGui.h>

Inheritance diagram for SLImGui:

Public Member Functions
	SLImGui (cbOnImGuiBuild buildCB, cbOnImGuiLoadConfig loadConfigCB, cbOnImGuiSaveConfig saveConfigCB, int dpi, SLIOBuffer fontDataProp, SLIOBuffer fontDataFixed)

	~SLImGui () override

void	init (const string &configPath) override
	Initializes OpenGL handles to zero and sets the ImGui key map. More...

void	onInitNewFrame (SLScene s, SLSceneView sv) override
	Inits a new frame for the ImGui system. More...

void	onResize (const SLRecti &viewport) override
	Callback if window got resized. More...

void	onPaint (const SLRecti &viewport) override
	Callback for main rendering for the ImGui GUI system. More...

void	onMouseDown (SLMouseButton button, SLint x, SLint y) override
	Callback on mouse button down event. More...

void	onMouseUp (SLMouseButton button, SLint x, SLint y) override
	Callback on mouse button up event. More...

void	onMouseMove (SLint xPos, SLint yPos) override
	Updates the mouse cursor position. More...

void	onMouseWheel (SLfloat yoffset) override
	Callback for the mouse scroll movement. More...

void	onKeyPress (SLKey key, SLKey mod) override
	Callback on key press event. More...

void	onKeyRelease (SLKey key, SLKey mod) override
	Callback on key release event. More...

void	onCharInput (SLuint c) override
	Callback on character input. More...

void	onClose () override
	Callback on closing the application. More...

void	renderExtraFrame (SLScene s, SLSceneView sv, SLint mouseX, SLint mouseY) override
	Renders an extra frame with the current mouse position. More...

bool	doNotDispatchKeyboard () override
	inform if user keyboard input was consumed by the ui More...

bool	doNotDispatchMouse () override
	inform if user mouse input was consumed by the ui More...

void	loadFonts (SLfloat fontPropDots, SLfloat fontFixedDots)
	Loads the proportional and fixed size font depending on the passed DPI. More...

void	drawMouseCursor (bool doDraw) override
	Turns on or off the mouse cursor drawing. More...

Public Member Functions inherited from SLUiInterface
virtual	~SLUiInterface ()

Static Public Attributes
static SLfloat	fontPropDots = 16.0f
	Default font size of proportional font. More...

static SLfloat	fontFixedDots = 13.0f
	Default font size of fixed size font. More...

Private Member Functions
void	deleteOpenGLObjects ()

void	createOpenGLObjects ()

void	printCompileErrors (SLint shaderHandle, const SLchar *src)
	Prints the compile errors in case of a GLSL compile failure. More...

Private Attributes
cbOnImGuiBuild	_build = nullptr

cbOnImGuiSaveConfig	_saveConfig = nullptr

SLfloat	_timeSec
	Time in seconds. More...

SLVec2f	_mousePosPX
	Mouse cursor position. More...

SLfloat	_mouseWheel
	Mouse wheel position. More...

SLbool	_mousePressed [3]
	Mouse button press state. More...

SLfloat	_fontPropDots
	Active font size of proportional font. More...

SLfloat	_fontFixedDots
	Active font size of fixed size font. More...

SLstring	_configPath
	Path to config files. More...

SLIOBuffer	_fontDataProp
	Raw data of proportional font file. More...

SLIOBuffer	_fontDataFixed
	Raw data of fixed size font file. More...

Detailed Description

ImGui Interface class for forwarding all events to the original ImGui Handlers.

ImGui is a super easy GUI library for the rendering of a UI with OpenGL. For more information see: https://github.com/ocornut/imgui

This class provides only the interface into ImGui. In the event handlers of SLSceneView the according callback in ImGui is called.
Compared to the older SLGLImGui class this class contains no OpenGL code and only calls the original backend functions in ImGui_impl_OpenGL3.cpp provided by the ImGui framework.
There is no UI drawn with this class. It must be defined in another class that provides the build function. For the Demo apps this is done in the file AppDemoGui and the build function is passed e.g. in glfwMain function of the app-demo project.

The full call stack for rendering one frame is:

The top-level onPaint of the app (Win, Linux, MacOS, Android or iOS)
- slUpdateAndPaint: C-Interface function of SLProject
  - SLSceneView::onPaint: Main onPaint function of a sceneview
    - SLImGui::onInitNewFrame: Initializes a new GUI frame
      - ImGui::NewFrame()
    - ... normal scene rendering of SLProject
    - SLSceneView::draw2DGL:
      - SLImGui::onPaint: Draws the UI with ImGUI

Definition at line 61 of file SLImGui.h.

Constructor & Destructor Documentation

◆ SLImGui()

SLImGui::SLImGui	(	cbOnImGuiBuild	buildCB,
		cbOnImGuiLoadConfig	loadConfigCB,
		cbOnImGuiSaveConfig	saveConfigCB,
		int	dpi,
		SLIOBuffer	fontDataProp,
		SLIOBuffer	fontDataFixed
	)

Definition at line 27 of file SLImGui.cpp.

 {
     _build           = buildCB;
     _saveConfig      = saveConfigCB;
     _fontPropDots    = 13.0f;
     _fontFixedDots   = 16.0f;
     _mouseWheel      = 0.0f;
     _mousePressed[0] = false;
     _mousePressed[1] = false;
     _mousePressed[2] = false;
     _fontDataProp    = fontDataProp;
     _fontDataFixed   = fontDataFixed;
  
     // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO();
     (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;  // Enable Gamepad Controls
     io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;     // Enable Docking
     io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;   // Enable Multi-Viewport / Platform Windows
     ImGui::StyleColorsDark();
  
     // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
     ImGuiStyle& style = ImGui::GetStyle();
     if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
     {
         style.WindowRounding              = 0.0f;
         style.Colors[ImGuiCol_WindowBg].w = 1.0f;
     }
  
     // Setup Platform/Renderer backends
     ImGui_ImplOpenGL3_Init(nullptr);
  
     // load config
     if (loadConfigCB)
         loadConfigCB(dpi);
  
     // load GUI fonts depending on the resolution
     loadFonts(SLImGui::fontPropDots, SLImGui::fontFixedDots);
 }

◆ ~SLImGui()

SLImGui::~SLImGui ( )

override

Definition at line 75 of file SLImGui.cpp.

 {
     onClose();
 }

Member Function Documentation

◆ createOpenGLObjects()

void SLImGui::createOpenGLObjects ( )

private

◆ deleteOpenGLObjects()

void SLImGui::deleteOpenGLObjects ( )

private

◆ doNotDispatchKeyboard()

bool SLImGui::doNotDispatchKeyboard ( )

inlineoverridevirtual

inform if user keyboard input was consumed by the ui

Reimplemented from SLUiInterface.

Definition at line 85 of file SLImGui.h.

85 { return ImGui::GetIO().WantCaptureKeyboard; }

◆ doNotDispatchMouse()

bool SLImGui::doNotDispatchMouse ( )

inlineoverridevirtual

inform if user mouse input was consumed by the ui

(e.g. the ui was hit by a mouse click. In this case the user input would not be forwarded to 3D scene graph)

Reimplemented from SLUiInterface.

Definition at line 86 of file SLImGui.h.

86 { return ImGui::GetIO().WantCaptureMouse; }

◆ drawMouseCursor()

void SLImGui::drawMouseCursor ( bool doDraw )

inlineoverridevirtual

Turns on or off the mouse cursor drawing.

Reimplemented from SLUiInterface.

Definition at line 88 of file SLImGui.h.

88 { ImGui::GetIO().MouseDrawCursor = doDraw; }

◆ init()

void SLImGui::init ( const string & configPath )

overridevirtual

Initializes OpenGL handles to zero and sets the ImGui key map.

Reimplemented from SLUiInterface.

Definition at line 81 of file SLImGui.cpp.

 {
     _fontPropDots    = 13.0f;
     _fontFixedDots   = 16.0f;
     _mouseWheel      = 0.0f;
     _mousePressed[0] = false;
     _mousePressed[1] = false;
     _mousePressed[2] = false;
     _configPath      = configPath;
  
     ImGuiIO& io                    = ImGui::GetIO();
     io.IniSavingRate               = 1.0f;
     io.IniFilename                 = NULL; // Disable ini config saving because we handle that ourselves
     io.KeyMap[ImGuiKey_Tab]        = K_tab;
     io.KeyMap[ImGuiKey_LeftArrow]  = K_left;
     io.KeyMap[ImGuiKey_RightArrow] = K_right;
     io.KeyMap[ImGuiKey_UpArrow]    = K_up;
     io.KeyMap[ImGuiKey_DownArrow]  = K_down;
     io.KeyMap[ImGuiKey_PageUp]     = K_pageUp;
     io.KeyMap[ImGuiKey_PageDown]   = K_pageUp;
     io.KeyMap[ImGuiKey_Home]       = K_home;
     io.KeyMap[ImGuiKey_End]        = K_end;
     io.KeyMap[ImGuiKey_Delete]     = K_delete;
     io.KeyMap[ImGuiKey_Backspace]  = K_backspace;
     io.KeyMap[ImGuiKey_Enter]      = K_enter;
     io.KeyMap[ImGuiKey_Escape]     = K_esc;
     io.KeyMap[ImGuiKey_Space]      = K_space;
     io.KeyMap[ImGuiKey_A]          = 'A';
     io.KeyMap[ImGuiKey_C]          = 'C';
     io.KeyMap[ImGuiKey_V]          = 'V';
     io.KeyMap[ImGuiKey_X]          = 'X';
     io.KeyMap[ImGuiKey_Y]          = 'Y';
     io.KeyMap[ImGuiKey_Z]          = 'Z';
  
     // The screen size is set again in onResize
     io.DisplaySize             = ImVec2(0, 0);
     io.DisplayFramebufferScale = ImVec2(1, 1);
  
 #if defined(SL_OS_ANDROID) || defined(SL_OS_MACIOS) || defined(SL_EMSCRIPTEN)
     io.MouseDrawCursor = false;
 #else
     io.MouseDrawCursor = true;
 #endif
  
     // Change default style to show the widget border
     ImGuiStyle& style     = ImGui::GetStyle();
     style.FrameBorderSize = 1;
  
     // Load ImGui config from imgui.ini
     SLstring iniFile = configPath + "imgui.ini";
     if (SLFileStorage::exists(iniFile, IOK_config))
     {
         SLstring iniContents = SLFileStorage::readIntoString(iniFile,
                                                              IOK_config);
         ImGui::LoadIniSettingsFromMemory(iniContents.c_str(),
                                          iniContents.size());
     }
 }

◆ loadFonts()

void SLImGui::loadFonts	(	SLfloat	fontPropDots,
		SLfloat	fontFixedDots
	)

Loads the proportional and fixed size font depending on the passed DPI.

Definition at line 151 of file SLImGui.cpp.

 {
     _fontPropDots  = fontPropDotsToLoad;
     _fontFixedDots = fontFixedDotsToLoad;
  
     ImGuiIO& io = ImGui::GetIO();
     io.Fonts->Clear();
  
     // Create copies of the font data because ImGUI takes ownerhip of the data.
     SLIOBuffer fontDataProp  = _fontDataProp.copy();
     SLIOBuffer fontDataFixed = _fontDataFixed.copy();
  
     // Load proportional font for menu and text displays
     io.Fonts->AddFontFromMemoryTTF(fontDataProp.data,
                                    static_cast<int>(fontDataProp.size),
                                    fontPropDotsToLoad);
  
     // Load fixed size font for statistics windows
     io.Fonts->AddFontFromMemoryTTF(fontDataFixed.data,
                                    static_cast<int>(fontDataFixed.size),
                                    fontFixedDotsToLoad);
     ImGui_ImplOpenGL3_DestroyDeviceObjects();
     ImGui_ImplOpenGL3_CreateDeviceObjects();
 }

◆ onCharInput()

void SLImGui::onCharInput ( SLuint c )

overridevirtual

Callback on character input.

Reimplemented from SLUiInterface.

Definition at line 298 of file SLImGui.cpp.

 {
     ImGuiIO& io = ImGui::GetIO();
     if (c > 0 && c < 0x10000)
         io.AddInputCharacter((unsigned short)c);
 }

◆ onClose()

void SLImGui::onClose ( )

overridevirtual

Callback on closing the application.

Reimplemented from SLUiInterface.

Definition at line 141 of file SLImGui.cpp.

 {
     ImGui::SetCurrentContext(ImGui::GetCurrentContext());
     if (_saveConfig)
         _saveConfig();
     ImGui_ImplOpenGL3_Shutdown();
     ImGui::DestroyContext();
 }

◆ onInitNewFrame()

void SLImGui::onInitNewFrame	(	SLScene *	s,
		SLSceneView *	sv
	)

overridevirtual

Inits a new frame for the ImGui system.

Reimplemented from SLUiInterface.

Definition at line 183 of file SLImGui.cpp.

 {
     if ((SLint)SLImGui::fontPropDots != (SLint)_fontPropDots ||
         (SLint)SLImGui::fontFixedDots != (SLint)_fontFixedDots)
         loadFonts(SLImGui::fontPropDots, SLImGui::fontFixedDots);
  
     ImGui_ImplOpenGL3_NewFrame();
  
     ImGuiIO& io = ImGui::GetIO();
  
     // Setup time step
     SLfloat nowSec = GlobalTimer::timeS();
     io.DeltaTime   = _timeSec > 0.0 ? nowSec - _timeSec : 1.0f / 60.0f;
     if (io.DeltaTime < 0) io.DeltaTime = 1.0f / 60.0f;
     _timeSec = nowSec;
  
     io.MouseWheel = _mouseWheel;
     _mouseWheel   = 0.0f;
  
     // Start the frame
     ImGui::NewFrame();
  
     // Save ImGui config to imgui.ini
     if (ImGui::GetIO().WantSaveIniSettings)
     {
         SLstring    iniFile = _configPath + "imgui.ini";
         size_t      iniContentsSize;
         const char* rawIniContents = ImGui::SaveIniSettingsToMemory(&iniContentsSize);
         SLstring    iniContents(rawIniContents, rawIniContents + iniContentsSize);
         SLFileStorage::writeString(iniFile, IOK_config, iniContents);
         ImGui::GetIO().WantSaveIniSettings = false;
     }
  
     // Call the _build function. The whole UI is constructed here
     // This function is provided by the top-level project.
     // For the SLProject demo apps this _build function is implemented in the
     // class SLDemoGui.
     if (_build)
         _build(s, sv);
 }

◆ onKeyPress()

void SLImGui::onKeyPress	(	SLKey	key,
		SLKey	mod
	)

overridevirtual

Callback on key press event.

Reimplemented from SLUiInterface.

Definition at line 278 of file SLImGui.cpp.

 {
     ImGuiIO& io      = ImGui::GetIO();
     io.KeysDown[key] = true;
     io.KeyCtrl       = mod & K_ctrl ? true : false;
     io.KeyShift      = mod & K_shift ? true : false;
     io.KeyAlt        = mod & K_alt ? true : false;
 }

◆ onKeyRelease()

void SLImGui::onKeyRelease	(	SLKey	key,
		SLKey	mod
	)

overridevirtual

Callback on key release event.

Reimplemented from SLUiInterface.

Definition at line 288 of file SLImGui.cpp.

 {
     ImGuiIO& io      = ImGui::GetIO();
     io.KeysDown[key] = false;
     io.KeyCtrl       = mod & K_ctrl ? true : false;
     io.KeyShift      = mod & K_shift ? true : false;
     io.KeyAlt        = mod & K_alt ? true : false;
 }

◆ onMouseDown()

void SLImGui::onMouseDown	(	SLMouseButton	button,
		SLint	x,
		SLint	y
	)

overridevirtual

Callback on mouse button down event.

Reimplemented from SLUiInterface.

Definition at line 242 of file SLImGui.cpp.

 {
     ImGuiIO& io = ImGui::GetIO();
     io.MousePos = ImVec2((SLfloat)x, (SLfloat)y);
     if (button == MB_left) io.MouseDown[0] = true;
     if (button == MB_right) io.MouseDown[1] = true;
     if (button == MB_middle) io.MouseDown[2] = true;
     // SL_LOG("D");
 }

◆ onMouseMove()

void SLImGui::onMouseMove	(	SLint	xPos,
		SLint	yPos
	)

overridevirtual

Updates the mouse cursor position.

Reimplemented from SLUiInterface.

Definition at line 264 of file SLImGui.cpp.

 {
     ImGui::GetIO().MousePos = ImVec2((SLfloat)xPos, (SLfloat)yPos);
     // SL_LOG("M");
 }

◆ onMouseUp()

void SLImGui::onMouseUp	(	SLMouseButton	button,
		SLint	x,
		SLint	y
	)

overridevirtual

Callback on mouse button up event.

Reimplemented from SLUiInterface.

Definition at line 253 of file SLImGui.cpp.

 {
     ImGuiIO& io = ImGui::GetIO();
     io.MousePos = ImVec2((SLfloat)x, (SLfloat)y);
     if (button == MB_left) io.MouseDown[0] = false;
     if (button == MB_right) io.MouseDown[1] = false;
     if (button == MB_middle) io.MouseDown[2] = false;
     // SL_LOG("U\n");
 }

◆ onMouseWheel()

void SLImGui::onMouseWheel ( SLfloat yoffset )

overridevirtual

Callback for the mouse scroll movement.

Reimplemented from SLUiInterface.

Definition at line 271 of file SLImGui.cpp.

 {
     // Use fractional mouse wheel, 1.0 unit 5 lines.
     _mouseWheel += yoffset;
 }

◆ onPaint()

void SLImGui::onPaint ( const SLRecti & viewport )

overridevirtual

Callback for main rendering for the ImGui GUI system.

Reimplemented from SLUiInterface.

Definition at line 234 of file SLImGui.cpp.

 {
     ImGuiIO& io = ImGui::GetIO();
     ImGui::Render();
     ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
 }

◆ onResize()

void SLImGui::onResize ( const SLRecti & viewport )

overridevirtual

Callback if window got resized.

Reimplemented from SLUiInterface.

Definition at line 225 of file SLImGui.cpp.

 {
     SLGLState* stateGL         = SLGLState::instance();
     ImGuiIO&   io              = ImGui::GetIO();
     io.DisplaySize             = ImVec2((SLfloat)viewport.width, (SLfloat)viewport.height);
     io.DisplayFramebufferScale = ImVec2(1, 1);
 }

◆ printCompileErrors()

void SLImGui::printCompileErrors	(	SLint	shaderHandle,
		const SLchar *	src
	)

private

Prints the compile errors in case of a GLSL compile failure.

Definition at line 178 of file SLImGui.cpp.

179 {

180 }

◆ renderExtraFrame()

void SLImGui::renderExtraFrame	(	SLScene *	s,
		SLSceneView *	sv,
		SLint	mouseX,
		SLint	mouseY
	)

overridevirtual

Renders an extra frame with the current mouse position.

Reimplemented from SLUiInterface.

Definition at line 306 of file SLImGui.cpp.

 {
     // If ImGui _build function exists render the ImGui
     if (_build)
     {
         ImGui::GetIO().MousePos = ImVec2((SLfloat)mouseX, (SLfloat)mouseY);
         onInitNewFrame(s, sv);
         onPaint(sv->viewportRect());
     }
 }

Member Data Documentation

◆ _build

cbOnImGuiBuild SLImGui::_build = nullptr

private

Definition at line 101 of file SLImGui.h.

◆ _configPath

SLstring SLImGui::_configPath

private

Path to config files.

Definition at line 112 of file SLImGui.h.

◆ _fontDataFixed

SLIOBuffer SLImGui::_fontDataFixed

private

Raw data of fixed size font file.

Definition at line 114 of file SLImGui.h.

◆ _fontDataProp

SLIOBuffer SLImGui::_fontDataProp

private

Raw data of proportional font file.

Definition at line 113 of file SLImGui.h.

◆ _fontFixedDots

SLfloat SLImGui::_fontFixedDots

private

Active font size of fixed size font.

Definition at line 111 of file SLImGui.h.

◆ _fontPropDots

SLfloat SLImGui::_fontPropDots

private

Active font size of proportional font.

Definition at line 110 of file SLImGui.h.

◆ _mousePosPX

SLVec2f SLImGui::_mousePosPX

private

Mouse cursor position.

Definition at line 107 of file SLImGui.h.

◆ _mousePressed

SLbool SLImGui::_mousePressed[3]

private

Mouse button press state.

Definition at line 109 of file SLImGui.h.

◆ _mouseWheel

SLfloat SLImGui::_mouseWheel

private

Mouse wheel position.

Definition at line 108 of file SLImGui.h.

◆ _saveConfig

cbOnImGuiSaveConfig SLImGui::_saveConfig = nullptr

private

Definition at line 104 of file SLImGui.h.

◆ _timeSec

SLfloat SLImGui::_timeSec

private

Time in seconds.

Definition at line 106 of file SLImGui.h.

◆ fontFixedDots

SLfloat SLImGui::fontFixedDots = 13.0f

static

Default font size of fixed size font.

Definition at line 92 of file SLImGui.h.

◆ fontPropDots

SLfloat SLImGui::fontPropDots = 16.0f

static

Default font size of proportional font.

Definition at line 91 of file SLImGui.h.

The documentation for this class was generated from the following files:

Public Member Functions

Static Public Attributes

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ SLImGui()

◆ ~SLImGui()

Member Function Documentation

◆ createOpenGLObjects()

◆ deleteOpenGLObjects()

◆ doNotDispatchKeyboard()

◆ doNotDispatchMouse()

◆ drawMouseCursor()

◆ init()

◆ loadFonts()

◆ onCharInput()

◆ onClose()

◆ onInitNewFrame()

◆ onKeyPress()

◆ onKeyRelease()

◆ onMouseDown()

◆ onMouseMove()

◆ onMouseUp()

◆ onMouseWheel()

◆ onPaint()

◆ onResize()

◆ printCompileErrors()

◆ renderExtraFrame()

Member Data Documentation

◆ _build

◆ _configPath

◆ _fontDataFixed

◆ _fontDataProp

◆ _fontFixedDots

◆ _fontPropDots

◆ _mousePosPX

◆ _mousePressed

◆ _mouseWheel

◆ _saveConfig

◆ _timeSec

◆ fontFixedDots

◆ fontPropDots