OpenGL state storage. More...

#include <vtkOpenGLState.h>

Collaboration diagram for vtkOpenGLState:

Classes
class	GLState

class	ScopedglBlendFuncSeparate

class	ScopedglClearColor

class	ScopedglColorMask

class	ScopedglDepthMask

class	ScopedglEnableDisable

class	ScopedglScissor

class	ScopedglViewport

class	ScopedValue

Public Member Functions
	vtkOpenGLState ()

void	GetBlendFuncState (int *)

bool	GetEnumState (unsigned int name)

void	SetEnumState (unsigned int name, bool value)

void	ResetEnumState (unsigned int name)
	convenience method to reset an enum state from current openGL context More...

void	Initialize (vtkOpenGLRenderWindow *)
	Initialize OpenGL context using current state. More...


void	vtkglClearColor (float red, float green, float blue, float alpha)

void	vtkglClearDepth (double depth)

void	vtkglDepthFunc (unsigned int val)

void	vtkglDepthMask (unsigned char flag)

void	vtkglColorMask (unsigned char r, unsigned char g, unsigned char b, unsigned char a)

void	vtkglViewport (int x, int y, int width, int height)

void	vtkglScissor (int x, int y, int width, int height)

void	vtkglEnable (unsigned int cap)

void	vtkglDisable (unsigned int cap)

void	vtkglBlendFunc (unsigned int sfactor, unsigned int dfactor)

void	vtkglBlendFuncSeparate (unsigned int sfactorRGB, unsigned int dfactorRGB, unsigned int sfactorAlpha, unsigned int dfactorAlpha)

void	vtkglBlendEquation (unsigned int val)

void	vtkglBlendEquationSeparate (unsigned int col, unsigned int alpha)

void	vtkglCullFace (unsigned int val)


void	ResetGlClearColorState ()

void	ResetGlClearDepthState ()

void	ResetGlDepthFuncState ()

void	ResetGlDepthMaskState ()

void	ResetGlColorMaskState ()

void	ResetGlViewportState ()

void	ResetGlScissorState ()

void	ResetGlBlendFuncState ()

void	ResetGlBlendEquationState ()

void	ResetGlCullFaceState ()


void	vtkglClear (unsigned int mask)


void	vtkglGetBooleanv (unsigned int pname, unsigned char *params)

void	vtkglGetIntegerv (unsigned int pname, int *params)

void	vtkglGetDoublev (unsigned int pname, double *params)

void	vtkglGetFloatv (unsigned int pname, float *params)

Protected Member Functions
void	BlendFuncSeparate (std::array< unsigned int, 4 > val)

void	ClearColor (std::array< float, 4 > val)

void	ColorMask (std::array< unsigned char, 4 > val)

void	Scissor (std::array< int, 4 > val)

void	Viewport (std::array< int, 4 > val)

void	CheckState ()
	Check that this OpenGL state has consistent values with the current OpenGL context. More...

Protected Attributes
GLState	CurrentState

Detailed Description

OpenGL state storage.

vtkOpenGLState is a class designed to keep track of the state of an OpenGL context. Applications using VTK have so much ontrol over the rendering process that is can be difficult in VTK code to know if the OpenGL state is correct for your code. The two traditional solutions have been to set everything yourself and to save and restore OpenGL state that you change. The former makes your code work, the latter hels prevent your code from breaking something else. The problem is that the former results in tons of redundent OpenGL calls and the later is done by querying the OpenGL state which can cause a pipeline sync/stall which is very slow.

To address these issues this class stores OpenGL state for commonly used functions. Requests made to change state to the current state become no-ops. Queries of state can be done by querying the state stored in this class without impacting the OpenGL driver.

To fascilitate saving state and restoring it this class contains a number of nested classes named Scoped<glFunction> that store the state of that glFunction and when they go out of scope they restore it. This is useful when you want to change the OpenGL state and then automatically restore it when done. They can be used as follows

{ vtkOpenGLState *ostate = renWin->GetState(); vtkOpenGLState::ScopedglDepthMask dmsaved(ostate); // the prior state is now saved ... ostate->glDepthMask(GL_TRUE); // maybe change the state ... etc } // prior state will be restored here as it goes out of scope

You must use this class to make stat changing OpenGL class otherwise the results will be undefined.

For convenience some OpenGL calls that do not impact state are also provided.

Definition at line 67 of file vtkOpenGLState.h.

Constructor & Destructor Documentation

vtkOpenGLState::vtkOpenGLState ( )

Member Function Documentation

void vtkOpenGLState::vtkglClearColor	(	float	red,
		float	green,
		float	blue,
		float	alpha
	)

void vtkOpenGLState::vtkglClearDepth ( double depth )

void vtkOpenGLState::vtkglDepthFunc ( unsigned int val )

void vtkOpenGLState::vtkglDepthMask ( unsigned char flag )

void vtkOpenGLState::vtkglColorMask	(	unsigned char	r,
		unsigned char	g,
		unsigned char	b,
		unsigned char	a
	)

void vtkOpenGLState::vtkglViewport	(	int	x,
		int	y,
		int	width,
		int	height
	)

void vtkOpenGLState::vtkglScissor	(	int	x,
		int	y,
		int	width,
		int	height
	)

void vtkOpenGLState::vtkglEnable ( unsigned int cap )

void vtkOpenGLState::vtkglDisable ( unsigned int cap )

void vtkOpenGLState::vtkglBlendFunc	(	unsigned int	sfactor,
		unsigned int	dfactor
	)

inline

Definition at line 86 of file vtkOpenGLState.h.

void vtkOpenGLState::vtkglBlendFuncSeparate	(	unsigned int	sfactorRGB,
		unsigned int	dfactorRGB,
		unsigned int	sfactorAlpha,
		unsigned int	dfactorAlpha
	)

void vtkOpenGLState::vtkglBlendEquation ( unsigned int val )

void vtkOpenGLState::vtkglBlendEquationSeparate	(	unsigned int	col,
		unsigned int	alpha
	)

void vtkOpenGLState::vtkglCullFace ( unsigned int val )

void vtkOpenGLState::ResetGlClearColorState ( )

void vtkOpenGLState::ResetGlClearDepthState ( )

void vtkOpenGLState::ResetGlDepthFuncState ( )

void vtkOpenGLState::ResetGlDepthMaskState ( )

void vtkOpenGLState::ResetGlColorMaskState ( )

void vtkOpenGLState::ResetGlViewportState ( )

void vtkOpenGLState::ResetGlScissorState ( )

void vtkOpenGLState::ResetGlBlendFuncState ( )

void vtkOpenGLState::ResetGlBlendEquationState ( )

void vtkOpenGLState::ResetGlCullFaceState ( )

void vtkOpenGLState::vtkglClear ( unsigned int mask )

void vtkOpenGLState::vtkglGetBooleanv	(	unsigned int	pname,
		unsigned char *	params
	)

void vtkOpenGLState::vtkglGetIntegerv	(	unsigned int	pname,
		int *	params
	)

void vtkOpenGLState::vtkglGetDoublev	(	unsigned int	pname,
		double *	params
	)

void vtkOpenGLState::vtkglGetFloatv	(	unsigned int	pname,
		float *	params
	)

void vtkOpenGLState::GetBlendFuncState ( int * )

bool vtkOpenGLState::GetEnumState ( unsigned int name )

void vtkOpenGLState::SetEnumState	(	unsigned int	name,
		bool	value
	)

void vtkOpenGLState::ResetEnumState ( unsigned int name )

convenience method to reset an enum state from current openGL context

void vtkOpenGLState::Initialize ( vtkOpenGLRenderWindow * )

Initialize OpenGL context using current state.

void vtkOpenGLState::BlendFuncSeparate ( std::array< unsigned int, 4 > val )

protected

void vtkOpenGLState::ClearColor ( std::array< float, 4 > val )

protected

void vtkOpenGLState::ColorMask ( std::array< unsigned char, 4 > val )

protected

void vtkOpenGLState::Scissor ( std::array< int, 4 > val )

protected

void vtkOpenGLState::Viewport ( std::array< int, 4 > val )

protected

void vtkOpenGLState::CheckState ( )

protected

Check that this OpenGL state has consistent values with the current OpenGL context.

Member Data Documentation

GLState vtkOpenGLState::CurrentState

protected

Definition at line 244 of file vtkOpenGLState.h.

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

/home/demarle/Source/VTK/release/8.2/build/Utilities/Doxygen/dox/Rendering/OpenGL2/vtkOpenGLState.h

Classes

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation