ImGuiWrapper Class Reference

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

#include <ImGuiWrapper.h>

Inheritance diagram for ImGuiWrapper:

Public Member Functions
	ImGuiWrapper (ImGuiContext *context, ImGuiRenderer *renderer)
	~ImGuiWrapper () override
void	init (const std::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 (SLint scrW, SLint scrH) 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...
virtual void	build (SLScene *s, SLSceneView *sv)=0
Public Member Functions inherited from SLUiInterface
virtual	~SLUiInterface ()
virtual void	init (const string &configPath)
	initialization (called by SLSceneView init) More...
virtual void	onResize (const SLRecti &viewportRect)
	inform the ui about scene view size change More...
virtual void	drawMouseCursor (bool doDraw)
	Turns on or off the mouse cursor drawing. More...

Protected Attributes
PanScrolling	_panScroll
ImGuiContext *	_context {nullptr}

Private Attributes
SLfloat	_timeSec
	Time in seconds. More...
SLfloat	_mouseWheel {0}
	Mouse wheel position. More...
ImGuiRenderer *	_renderer {nullptr}

Detailed Description

ImGui Interface class for forwarding all events to the 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.
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 class SLDemoGui 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::newFrame: Initializes a new GUI frame
        • ImGui::NewFrame()
        • SLImGui::build: The UI build function
      • ... normal scene rendering of SLProject
      • SLSceneView::draw2DGL:
        • ImGui::Render
          • SLImGui::render(ImGui::GetDrawData())
          • SLDemoGui::buildDemoGui: Builds the full UI ImGuiWrapper implements SLUiInterface for ImGui.

The interface function are called by a SLSceneView instance

Definition at line 250 of file ImGuiWrapper.h.

Constructor & Destructor Documentation

ImGuiWrapper()

ImGuiWrapper::ImGuiWrapper	(	ImGuiContext *	context,
		ImGuiRenderer *	renderer
	)

Definition at line 431 of file ImGuiWrapper.cpp.

  : _context(context),
    _renderer(renderer)
{
    assert(_context);
    assert(_renderer);
}

~ImGuiWrapper()

ImGuiWrapper::~ImGuiWrapper ( )

override

Definition at line 439 of file ImGuiWrapper.cpp.

{
}

Member Function Documentation

build()

virtual void ImGuiWrapper::build ( SLScene *  s, SLSceneView *  sv  )

pure virtual

doNotDispatchKeyboard()

bool ImGuiWrapper::doNotDispatchKeyboard ( )

overridevirtual

inform if user keyboard input was consumed by the ui

Reimplemented from SLUiInterface.

Definition at line 592 of file ImGuiWrapper.cpp.

{
    return _context->IO.WantCaptureKeyboard;
}

doNotDispatchMouse()

bool ImGuiWrapper::doNotDispatchMouse ( )

overridevirtual

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 597 of file ImGuiWrapper.cpp.

{
    return _context->IO.WantCaptureMouse;
}

init()

void ImGuiWrapper::init ( const std::string &  configPath )

override

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

Definition at line 444 of file ImGuiWrapper.cpp.

{
    _mouseWheel = 0.0f;
}

onCharInput()

void ImGuiWrapper::onCharInput ( SLuint  c )

overridevirtual

Callback on character input.

Reimplemented from SLUiInterface.

Definition at line 571 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io = _context->IO;
    if (c > 0 && c < 0x10000)
        io.AddInputCharacter((unsigned short)c);
}

onClose()

void ImGuiWrapper::onClose ( )

overridevirtual

Callback on closing the application.

Reimplemented from SLUiInterface.

Definition at line 579 of file ImGuiWrapper.cpp.

{
}

onInitNewFrame()

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

overridevirtual

Inits a new frame for the ImGui system.

Reimplemented from SLUiInterface.

Definition at line 450 of file ImGuiWrapper.cpp.

{
    // If no build function is provided there is no ImGui
    // if (!build) return;
 
    // if ((SLint)ImGuiWrapper::fontPropDots != (SLint)_fontPropDots ||
    //     (SLint)ImGuiWrapper::fontFixedDots != (SLint)_fontFixedDots)
    //     loadFonts(ImGuiWrapper::fontPropDots, ImGuiWrapper::fontFixedDots);
 
    // if (!_fontTexture)
    //     createOpenGLObjects();
 
    ImGuiIO& io = _context->IO;
 
    // 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;
 
    if (_panScroll.enabled())
    {
        io.MouseWheel = _panScroll.getScrollInMouseWheelCoords(io.MouseDown[0], _context->FontSize, nowSec);
    }
    else
    {
        io.MouseWheel = _mouseWheel;
        _mouseWheel   = 0.0f;
    }
 
    // Start the frame
    ImGui::SetCurrentContext(_context);
    ImGui::NewFrame();
 
    // Call the build function to construct the ui
    build(s, sv);
    ImGui::SetCurrentContext(nullptr);
    // SL_LOG(".");
}

onKeyPress()

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

overridevirtual

Callback on key press event.

Reimplemented from SLUiInterface.

Definition at line 551 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io      = _context->IO;
    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 ImGuiWrapper::onKeyRelease ( SLKey  key, SLKey  mod  )

overridevirtual

Callback on key release event.

Reimplemented from SLUiInterface.

Definition at line 561 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io      = _context->IO;
    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 ImGuiWrapper::onMouseDown ( SLMouseButton  button, SLint  x, SLint  y  )

overridevirtual

Callback on mouse button down event.

Reimplemented from SLUiInterface.

Definition at line 507 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io = _context->IO;
    io.MousePos = ImVec2((SLfloat)x, (SLfloat)y);
    if (button == MB_left)
    {
        io.MouseDown[0] = true;
        if (_panScroll.enabled())
            _panScroll.start((SLfloat)y);
    }
    if (button == MB_right) io.MouseDown[1] = true;
    if (button == MB_middle) io.MouseDown[2] = true;
    // SL_LOG("D");
}

onMouseMove()

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

overridevirtual

Updates the mouse cursor position.

Reimplemented from SLUiInterface.

Definition at line 534 of file ImGuiWrapper.cpp.

{
    _context->IO.MousePos = ImVec2((SLfloat)xPos, (SLfloat)yPos);
    ImGuiIO& io           = _context->IO;
    if (io.MouseDown[0] && _panScroll.enabled())
        _panScroll.moveTo((float)yPos);
    // SL_LOG("M");
}

onMouseUp()

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

overridevirtual

Callback on mouse button up event.

Reimplemented from SLUiInterface.

Definition at line 523 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io = _context->IO;
    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");
}

onMouseWheel()

void ImGuiWrapper::onMouseWheel ( SLfloat  yoffset )

overridevirtual

Callback for the mouse scroll movement.

Reimplemented from SLUiInterface.

Definition at line 544 of file ImGuiWrapper.cpp.

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

onPaint()

void ImGuiWrapper::onPaint ( const SLRecti &  viewport )

overridevirtual

Callback for main rendering for the ImGui GUI system.

Reimplemented from SLUiInterface.

Definition at line 500 of file ImGuiWrapper.cpp.

{
    // do the opengl rendering
    _renderer->render(viewportRect);
}

onResize()

void ImGuiWrapper::onResize ( SLint  scrW, SLint  scrH  )

override

Callback if window got resized.

Definition at line 491 of file ImGuiWrapper.cpp.

{
    ImGuiIO& io                = _context->IO;
    io.DisplaySize             = ImVec2((SLfloat)scrW, (SLfloat)scrH);
    io.DisplayFramebufferScale = ImVec2(1, 1);
}

renderExtraFrame()

void ImGuiWrapper::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 584 of file ImGuiWrapper.cpp.

{
    // If ImGui build function exists render the ImGui
    _context->IO.MousePos = ImVec2((SLfloat)mouseX, (SLfloat)mouseY);
    onInitNewFrame(s, sv);
    onPaint(sv->viewportRect());
}

Member Data Documentation

_context

ImGuiContext* ImGuiWrapper::_context {nullptr}

protected

Definition at line 278 of file ImGuiWrapper.h.

_mouseWheel

SLfloat ImGuiWrapper::_mouseWheel {0}

private

Mouse wheel position.

Definition at line 282 of file ImGuiWrapper.h.

_panScroll

PanScrolling ImGuiWrapper::_panScroll

protected

Definition at line 277 of file ImGuiWrapper.h.

_renderer

ImGuiRenderer* ImGuiWrapper::_renderer {nullptr}

private

Definition at line 284 of file ImGuiWrapper.h.

_timeSec

SLfloat ImGuiWrapper::_timeSec

private

Time in seconds.

Definition at line 281 of file ImGuiWrapper.h.

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

• ImGuiWrapper.h
• ImGuiWrapper.cpp