SelectorGPU Class Reference

Implements the GPU based object selection. More...

#include <selectorGPU.hpp>

Inheritance diagram for SelectorGPU:

Public Member Functions
	SelectorGPU (const std::string &name, Scene *scene)
	Defined in compute shader. More...
	~SelectorGPU ()
void	changeMode ()
	debug, change kernel count More...
void	pickObject (const glm::ivec2 &mouse)
	select closest object to mouse More...
void	getPixelCount (int &width, int &height) const
Public Member Functions inherited from SelectorBase
	SelectorBase (const std::string &name, Scene *scene)
	~SelectorBase ()
void	reset ()
	set up EffectObject More...
void	draw () const
	draw selectable object ids into a texture More...
void	update (double deltaT)
	empty function More...
int	getBufferWidth () const
int	getBufferHeight () const
size_t	getLastSelected () const
size_t	getLastDistance () const
Public Member Functions inherited from SceneObject
	SceneObject (std::shared_ptr< SceneObject > &effectParent, const glm::mat4 &modelMatrix=glm::mat4(1))
	SceneObject (const std::string &name, Scene *scene=0, Model *model=0, const glm::mat4 &modelMatrix=glm::mat4(1))
virtual	~SceneObject ()
Model *	getModel () const
Shader *	getShader () const
glm::mat4	getModelMatrix () const
glm::mat4	getGlobalModelMatrix () const
std::string	getName () const
std::shared_ptr< SceneObject >	getParent () const
void	setAnimationTime (double time)
bool	setAnimation (const Animation &anim)
bool	delChild (size_t idx)
bool	getChild (size_t idx, std::shared_ptr< SceneObject > &child) const
bool	addChild (std::shared_ptr< SceneObject > &child)
bool	remEffect (const std::string &name)
SceneObject *	getEffect (const std::string &name) const
bool	addEffect (const std::string &name, std::unique_ptr< SceneObject > &effect)
bool	doNotRender ()
bool	getIsVolSun ()
virtual bool	animate (double time)
virtual void	setShader (Shader *val)

Private Types
enum	{ KernelSize = 8 }

Private Attributes
int	mode
	debug, help to set window More...
int	windowX
	number of kernels used in compute shader More...
int	windowY
	number of kernels used in compute shader More...
GLuint	objectBuffer
	buffer to store compute shader result on GPU More...
Shader *	computeShader
	the compute shader to use More...
std::vector< GLuint >	buffer
	buffer to store compute shader result on CPU More...

Additional Inherited Members
Public Types inherited from SceneObject
typedef std::vector< std::pair< double, glm::mat4 > >	Animation
Protected Attributes inherited from SelectorBase
int	width
	width of screen More...
int	height
	height of screen More...
GLuint	idBuffer
	frame buffer More...
GLuint	idTexture
	texture of rendered object indices More...
size_t	lastDistance
	distance after pickObject() call More...
size_t	lastSelected
	selected object id after pickObject() call More...
Protected Attributes inherited from SceneObject
GLuint	vao
Scene *	scene
Model *	model
Shader *	shader
glm::mat4	modelMatrix
std::string	name
std::weak_ptr< SceneObject >	parent
std::vector< std::shared_ptr< SceneObject > >	childs
std::map< std::string, std::unique_ptr< SceneObject > >	effectChilds
size_t	animIDX
Animation	animation
bool	norender
bool	isVolSun

Detailed Description

Implements the GPU based object selection.

The SelectorGPU class implements an alternative selection method. The selectable objects are rendered into a texture the same way as in the quadtree based method. After rendering a compute shader is executed on the texture, returning the id and the distance of the closest object to the mouse. This way memory transfer and cpu time can be saved. By selecting different count of kernels, the size of the screen ROI can be modified. The following pseudocode demonstrates the object selection by the compute shader:

//the compute shader, executed for each pixel

ivec2 pixel = compute pixel position from thread id

if pixel out of pick buffer bounds
 return;

//load object id at pixel position
uint id = imageLoad(pickBuffer, pixel)

//no object at pixel
if id == 0
 return;

//compute distance, pack id and store if less
uint dist = (distance(mouse, pixel) << 16) | id;
atomicMin(buffer, dist);

Author

Adam

Member Enumeration Documentation

anonymous enum

private

Enumerator
KernelSize

Constructor & Destructor Documentation

SelectorGPU::SelectorGPU	(	const std::string &	name,
		Scene *	scene
	)

Defined in compute shader.

SelectorGPU::~SelectorGPU

(

)

Member Function Documentation

void SelectorGPU::changeMode ( )

virtual

debug, change kernel count

Implements SelectorBase.

void SelectorGPU::getPixelCount ( int &  width, int &  height  ) const

inline

void SelectorGPU::pickObject ( const glm::ivec2 &  mouse )

virtual

select closest object to mouse

Implements SelectorBase.

Member Data Documentation

std::vector<GLuint> SelectorGPU::buffer

private

buffer to store compute shader result on CPU

Shader* SelectorGPU::computeShader

private

the compute shader to use

int SelectorGPU::mode

private

debug, help to set window

GLuint SelectorGPU::objectBuffer

private

buffer to store compute shader result on GPU

int SelectorGPU::windowX

private

number of kernels used in compute shader

int SelectorGPU::windowY

private

number of kernels used in compute shader

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

• C:/Users/FLx/Selektron/include/selectorGPU.hpp
• C:/Users/FLx/Selektron/src/selectorGPU.cpp