Abstract Class to run an OpenGL application. The following methods must be overridden:
More...

#include <OpenGLEngine.hpp>

Inheritance diagram for CSCI441::OpenGLEngine:

Public Member Functions
	OpenGLEngine (const OpenGLEngine &)=delete
	do not allow engines to be copied

OpenGLEngine &	operator= (const OpenGLEngine &)=delete
	do not allow engines to be copied

virtual void	initialize ()
	Initialize everything needed for OpenGL Rendering. This includes in order: GLFW, function pointers, OpenGL, Shader Programs, Buffer Objects, Textures, and any Scene information.

virtual void	run ()=0
	Initiate the draw loop.

virtual void	shutdown ()
	Cleanup everything needed for OpenGL Rendering. This includes freeing memory for data used in: any Scene information, Textures, Buffer Objects, Shader Programs, OpenGL, function pointers, GLFW.

virtual void	turnDebuggingOn () noexcept final
	Enable logging to command line.

virtual void	turnDebuggingOff () noexcept final
	Disable logging to command line.

virtual bool	isDebuggingEnabled () const noexcept final
	Returns if logging is enabled.

virtual bool	isExtensionEnabled (const std::string EXT) const noexcept final
	Returns if OpenGL extension exists.

virtual void	setCurrentWindowSize (const int WINDOW_WIDTH, const int WINDOW_HEIGHT) final
	Set the new window size.

virtual int	getWindowHeight () const noexcept final
	Return the height of the window.

virtual int	getWindowWidth () const noexcept final
	Return the width of the window.

virtual GLFWwindow *	getWindow () const noexcept final
	Return the window object.

virtual void	setWindowShouldClose () final
	Tell our engine's window to close.

virtual unsigned short	getError () noexcept final
	Return current value of error code and clear the error code back to no error.

Static Public Attributes
static const unsigned short	OPENGL_ENGINE_ERROR_NO_ERROR = 0
	no error is present, everything is currently working

static const unsigned short	OPENGL_ENGINE_ERROR_GLFW_INIT = 1
	an error occurred while initializing GLFW

static const unsigned short	OPENGL_ENGINE_ERROR_GLFW_WINDOW = 2
	an error occurred while creating the GLFW window

static const unsigned short	OPENGL_ENGINE_ERROR_GLEW_INIT = 3
	an error occurred while initializing GLEW

static const unsigned short	OPENGL_ENGINE_ERROR_GLAD_INIT = 4
	an error occurred while initializing GLAD

static const unsigned short	OPENGL_ENGINE_ERROR_UNKNOWN = 5
	a new error that does not correspond to a predefined scenario has occurred

static const unsigned short	OPENGL_ENGINE_ERROR_LAST = OPENGL_ENGINE_ERROR_UNKNOWN
	stores the error code number of the last possible error, this corresponds to the max error code value.

static const unsigned short	OPENGL_ENGINE_ERROR_SIZE = OPENGL_ENGINE_ERROR_LAST + 1
	stores the number of unique error codes that can be generated

Protected Member Functions
	OpenGLEngine (int OPENGL_MAJOR_VERSION, int OPENGL_MINOR_VERSION, int WINDOW_WIDTH, int WINDOW_HEIGHT, const char *WINDOW_TITLE, bool WINDOW_RESIZABLE=GLFW_FALSE)
	initializes our OpenGL Engine by setting the OpenGL context and GLFW window parameters

virtual	~OpenGLEngine ()
	cleans up our OpenGL Engine by destroying the OpenGL context, GLFW window, and cleaning up all GPU resources

virtual void	mSetupGLFW ()
	Used to setup everything GLFW related. This includes the OpenGL context and our window. By default, completes the following steps in order:

virtual void	mSetupOpenGL ()=0
	override to enable specific OpenGL features

virtual void	mSetupShaders ()
	override to register any shaders with the GPU

virtual void	mSetupBuffers ()
	override to register any buffer objects with the GPU

virtual void	mSetupTextures ()
	override to register any textures with the GPU

virtual void	mSetupScene ()
	override to setup any scene specific information

virtual void	mCleanupScene ()
	override to cleanup any scene specific information

virtual void	mCleanupTextures ()
	override to cleanup any textures from the GPU

virtual void	mCleanupBuffers ()
	override to cleanup any buffer objects from the GPU

virtual void	mCleanupShaders ()
	override to cleanup any shaders from the GPU

virtual void	mCleanupOpenGL ()
	override to cleanup any specific OpenGL features

virtual void	mCleanupGLFW ()
	Destroys the associated GLFW window and terminates the GLFW instance.

Static Protected Member Functions
static void	mErrorCallback (int error, const char *DESCRIPTION)
	We will register this function as GLFW's error callback. When an error within OpenGL occurs, GLFW will tell us by calling this function. We can then print this info to the terminal to alert the user.

static void	mDebugMessageCallback (GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar message, const void userParam)
	callback called whenever a debug message is signaled

static void	mWindowResizeCallback (GLFWwindow *pWindow, int width, int height)

Protected Attributes
bool	DEBUG
	if information should be printed to console while running

unsigned int	mErrorCode
	tracks the current status of the OpenGL engine via error codes

int	mOpenGLMajorVersion
	the major version of the requested OpenGL context

int	mOpenGLMinorVersion
	the minor version of the requested OpenGL context

int	mWindowWidth
	the window width of the requested GLFW window

int	mWindowHeight
	the window height of the requested GLFW window

bool	mWindowResizable
	if the GLFW window can be resized while open

char *	mWindowTitle
	the title of the GLFW window

GLFWwindow *	mpWindow
	pointer to the GLFW window object

Detailed Description

Abstract Class to run an OpenGL application. The following methods must be overridden:

Constructor & Destructor Documentation

◆ OpenGLEngine()

CSCI441::OpenGLEngine::OpenGLEngine	(	int	OPENGL_MAJOR_VERSION,
		int	OPENGL_MINOR_VERSION,
		int	WINDOW_WIDTH,
		int	WINDOW_HEIGHT,
		const char *	WINDOW_TITLE,
		bool	WINDOW_RESIZABLE = `GLFW_FALSE`
	)

inlineprotected

initializes our OpenGL Engine by setting the OpenGL context and GLFW window parameters

Parameters

OPENGL_MAJOR_VERSION	OpenGL Major version to request context of (for example 4.X)
OPENGL_MINOR_VERSION	OpenGL Minor version to request context of (for example X.1)
WINDOW_WIDTH	width of window to request creation of
WINDOW_HEIGHT	height of window to request creation of
WINDOW_TITLE	title to place on window bar
WINDOW_RESIZABLE	if window should be resizable or not (defaults to false)

Note: does not actually create the context nor the window at this time. To do so, call the initialize() method after the object has been created

Member Function Documentation

◆ initialize()

void CSCI441::OpenGLEngine::initialize ( )

inlinevirtual

Initialize everything needed for OpenGL Rendering. This includes in order: GLFW, function pointers, OpenGL, Shader Programs, Buffer Objects, Textures, and any Scene information.

Warning: If this method is overridden, then the parent implementation must be called first as part of the derived implementation

◆ isExtensionEnabled()

virtual bool CSCI441::OpenGLEngine::isExtensionEnabled ( const std::string EXT ) const

inlinefinalvirtualnoexcept

Returns if OpenGL extension exists.

Parameters

EXT	name of extension

Returns: true if extension exists, false otherwise

◆ mCleanupBuffers()

virtual void CSCI441::OpenGLEngine::mCleanupBuffers ( )

inlineprotectedvirtual

override to cleanup any buffer objects from the GPU

Note: called after textures have been cleaned up and prior to shaders, OpenGL, or GLFW being cleaned

◆ mCleanupGLFW()

void CSCI441::OpenGLEngine::mCleanupGLFW ( )

inlineprotectedvirtual

Destroys the associated GLFW window and terminates the GLFW instance.

Warning: If this method is overridden, then the parent implementation must be called last as part of the derived implementation

Note: final cleanup method to be called

◆ mCleanupOpenGL()

virtual void CSCI441::OpenGLEngine::mCleanupOpenGL ( )

inlineprotectedvirtual

override to cleanup any specific OpenGL features

Note: called after shaders have been cleaned and prior to GLFW being cleaned

◆ mCleanupScene()

virtual void CSCI441::OpenGLEngine::mCleanupScene ( )

inlineprotectedvirtual

override to cleanup any scene specific information

Note: first cleanup method to be called

◆ mCleanupShaders()

virtual void CSCI441::OpenGLEngine::mCleanupShaders ( )

inlineprotectedvirtual

override to cleanup any shaders from the GPU

Note: called after buffer objects have been cleaned up and prior to OpenGL or GLFW being cleaned

◆ mCleanupTextures()

virtual void CSCI441::OpenGLEngine::mCleanupTextures ( )

inlineprotectedvirtual

override to cleanup any textures from the GPU

Note: called after scene cleanup and prior to any other cleanup processes

◆ mSetupBuffers()

virtual void CSCI441::OpenGLEngine::mSetupBuffers ( )

inlineprotectedvirtual

override to register any buffer objects with the GPU

Note: called after shaders are setup and prior to textures or scene setup has been performed; If overridden, then it is likely that mCleanupBuffers should be overridden as well

◆ mSetupGLFW()

void CSCI441::OpenGLEngine::mSetupGLFW ( )

inlineprotectedvirtual

Used to setup everything GLFW related. This includes the OpenGL context and our window.

By default, completes the following steps in order:

sets error callback
initializes GLFW
sets window hints for OpenGL MAJOR.minor
requests Core Profile
requests double buffering
marks window as resizable or not based on constructor creation
creates a window
makes the window the current context
sets the swap interval to 1
Note
This method should be overridden if any additional callbacks need to be registered. When registering additional callbacks, the parent implementation must be called first and then the additional callbacks may be registered as desired.

If overridden, then it is likely that mCleanupGLFW should be overridden as well

Sets mErrorCode if process does not complete successfully

◆ mSetupOpenGL()

virtual void CSCI441::OpenGLEngine::mSetupOpenGL ( )

protectedpure virtual

override to enable specific OpenGL features

Note: called after GLFW window is created and OpenGL context is created and prior to any other shader, buffer, texture, or scene setup has been performed; If overridden, then it is likely that mCleanupOpenGL should be overridden as well

◆ mSetupScene()

virtual void CSCI441::OpenGLEngine::mSetupScene ( )

inlineprotectedvirtual

override to setup any scene specific information

Note: final setup method to be called; If overridden, then it is likely that mCleanupScene should be overridden as well

◆ mSetupShaders()

virtual void CSCI441::OpenGLEngine::mSetupShaders ( )

inlineprotectedvirtual

override to register any shaders with the GPU

Note: called after OpenGL features are setup and prior to buffers, textures, or scene setup has been performed; If overridden, then it is likely that mCleanupShaders should be overridden as well

◆ mSetupTextures()

virtual void CSCI441::OpenGLEngine::mSetupTextures ( )

inlineprotectedvirtual

override to register any textures with the GPU

Note: called after buffer objects are setup and prior to scene setup has been performed; If overridden, then it is likely that mCleanupTextures should be overridden as well

◆ mWindowResizeCallback()

void CSCI441::OpenGLEngine::mWindowResizeCallback	(	GLFWwindow *	pWindow,
		int	width,
		int	height
	)

inlinestaticprotected

callback called when GLFW pWindow is resized. internally updated mWindowWidth and mWindowHeight to new values

Parameters

pWindow	pointer to the window that was resized
width	new width of the window
height	new height of the window

◆ setCurrentWindowSize()

virtual void CSCI441::OpenGLEngine::setCurrentWindowSize	(	const int	WINDOW_WIDTH,
		const int	WINDOW_HEIGHT
	)

inlinefinalvirtual

Set the new window size.

Parameters

WINDOW_WIDTH	width of the new window
WINDOW_HEIGHT	height of the new window

Warning: This function does not cause the window to be resized, rather after the window has been resized this function is used to update the data members storing the current window size.

◆ shutdown()

void CSCI441::OpenGLEngine::shutdown ( )

inlinevirtual

Cleanup everything needed for OpenGL Rendering. This includes freeing memory for data used in: any Scene information, Textures, Buffer Objects, Shader Programs, OpenGL, function pointers, GLFW.

Warning: If this method is overridden, then the parent implementation must be called last as part of the derived implementation

◆ turnDebuggingOff()

virtual void CSCI441::OpenGLEngine::turnDebuggingOff ( )

inlinefinalvirtualnoexcept

Disable logging to command line.

Note: Enabled by default

◆ turnDebuggingOn()

virtual void CSCI441::OpenGLEngine::turnDebuggingOn ( )

inlinefinalvirtualnoexcept

Enable logging to command line.

Note: Enabled by default

Member Data Documentation

◆ DEBUG

bool CSCI441::OpenGLEngine::DEBUG

protected

if information should be printed to console while running

Note: defaults to true

◆ mOpenGLMajorVersion

int CSCI441::OpenGLEngine::mOpenGLMajorVersion

protected

the major version of the requested OpenGL context

Note: may not correspond to the actual OpenGL context created

◆ mOpenGLMinorVersion

int CSCI441::OpenGLEngine::mOpenGLMinorVersion

protected

the minor version of the requested OpenGL context

Note: may not correspond to the actual OpenGL context created

◆ mWindowHeight

int CSCI441::OpenGLEngine::mWindowHeight

protected

the window height of the requested GLFW window

Note: may not correspond to the actual GLFW window created

◆ mWindowResizable

bool CSCI441::OpenGLEngine::mWindowResizable

protected

if the GLFW window can be resized while open

Note: by default false

◆ mWindowWidth

int CSCI441::OpenGLEngine::mWindowWidth

protected

the window width of the requested GLFW window

Note: may not correspond to the actual GLFW window created

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

OpenGLEngine.hpp

Public Member Functions

Static Public Attributes

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ OpenGLEngine()

Member Function Documentation

◆ initialize()

◆ isExtensionEnabled()

◆ mCleanupBuffers()

◆ mCleanupGLFW()

◆ mCleanupOpenGL()

◆ mCleanupScene()

◆ mCleanupShaders()

◆ mCleanupTextures()

◆ mSetupBuffers()

◆ mSetupGLFW()

◆ mSetupOpenGL()

◆ mSetupScene()

◆ mSetupShaders()

◆ mSetupTextures()

◆ mWindowResizeCallback()

◆ setCurrentWindowSize()

◆ shutdown()

◆ turnDebuggingOff()

◆ turnDebuggingOn()

Member Data Documentation

◆ DEBUG

◆ mOpenGLMajorVersion

◆ mOpenGLMinorVersion

◆ mWindowHeight

◆ mWindowResizable

◆ mWindowWidth