NL3D::CMotionBlur Class Reference

#include <motion_blur.h>

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Detailed Description

This class help perfoming motion blur on a portion of the screen

Author:

Nicolas Vizerie

Nevrax France

Date:

2001

Definition at line 45 of file motion_blur.h.

Public Member Functions
	CMotionBlur ()
void	performMotionBlur (IDriver *driver, float motionBlurAmount)
void	releaseMotionBlur ()
	release the resources used by motion blur
void	startMotionBlur (uint x, uint y, uint width, uint height)
Protected Attributes
uint	_H
NLMISC::CSmartPtr< ITexture >	_Tex
uint	_W
uint	_X
uint	_Y

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Constructor & Destructor Documentation

NL3D::CMotionBlur::CMotionBlur (   )

Definition at line 39 of file motion_blur.cpp. : _Tex(NULL), _X(0), _Y(0), _W(0), _H(0) { }

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Member Function Documentation

void NL3D::CMotionBlur::performMotionBlur (  IDriver *  driver, float  motionBlurAmount )

perform motion blur, using the given driver This can only have been called between a startMotionBlur / releaseMotionBlur pair. It must be called after the scene has been drawn of course. WARNING : this change the projection matrix and the frustum in the driver. Parameters: motionBlurAmount  ranges from 0.f to 1.f. Blend using the following : motionBlurAmount * previous frame + (1 - motionBlurAmount) * current Frame buffer state Definition at line 62 of file motion_blur.cpp. References _H, _W, NL3D::IDriver::activeVertexBuffer(), NL3D::IDriver::copyFrameBufferToTexture(), NL3D::IDriver::getWindowSize(), height, nlassert, NLMISC::raiseToNextPowerOf2(), NL3D::IDriver::renderQuads(), NL3D::CMaterial::setBlend(), NL3D::CMaterial::setBlendFunc(), NL3D::CMaterial::setColor(), NL3D::CMaterial::setDoubleSided(), NL3D::IDriver::setFrustum(), NL3D::CVertexBuffer::setNumVertices(), NL3D::CVertexBuffer::setTexCoord(), NL3D::CMaterial::setTexture(), NL3D::IDriver::setupModelMatrix(), NL3D::IDriver::setupViewMatrix(), NL3D::CVertexBuffer::setVertexCoord(), NL3D::CVertexBuffer::setVertexFormat(), NL3D::CMaterial::setZFunc(), NL3D::CMaterial::setZWrite(), NL3D::CMaterial::texEnvArg0Alpha(), NL3D::CMaterial::texEnvOpAlpha(), NL3D::CMaterial::texEnvOpRGB(), uint, uint32, uint8, and width. { nlassert(_Tex) ; //start motion blur has not been called !! nlassert(driver) ; nlassert(motionBlurAmount >= 0.f && motionBlurAmount <= 1.f) ; static CVertexBuffer vb ; vb.setVertexFormat(CVertexBuffer::PositionFlag | CVertexBuffer::TexCoord0Flag ) ; vb.setNumVertices(4) ; uint32 width, height ; driver->getWindowSize(width, height) ; float widthRatio = _W / (float) NLMISC::raiseToNextPowerOf2 (_W) ; float heightRatio = _H / (float) NLMISC::raiseToNextPowerOf2 (_H) ; driver->setFrustum(0, (float) width, 0, (float) height, -1, 1, false) ; for (uint sn = 0 ; sn < 2 ; ++sn) { vb.setTexCoord(0, sn, CUV(0, 0)) ; vb.setTexCoord(1, sn, CUV(widthRatio, 0)) ; vb.setTexCoord(2, sn, CUV(widthRatio, heightRatio)) ; vb.setTexCoord(3, sn, CUV(0, heightRatio)) ; } static CMaterial mbMat ; static bool matSetup = false ; // set to true when mbMat has Been setup if (!matSetup) { mbMat.setBlend(true) ; mbMat.setBlendFunc(CMaterial::srcalpha, CMaterial::invsrcalpha) ; mbMat.setZWrite(false) ; mbMat.setZFunc(CMaterial::always) ; // stage 0 mbMat.setTexture(0, _Tex) ; mbMat.texEnvOpRGB(0, CMaterial::Replace ); mbMat.texEnvArg0Alpha(0, CMaterial::Diffuse, CMaterial::SrcAlpha); mbMat.texEnvOpAlpha(0, CMaterial::Replace); mbMat.setDoubleSided(true) ; matSetup = true ; } mbMat.setColor(CRGBA(255, 255, 255, (uint8) (255.f * motionBlurAmount) ) ) ; vb.setVertexCoord(0, CVector((float) _X, 0, 0) ) ; vb.setVertexCoord(1, CVector((float) (_X + _W), 0 ,0) ) ; vb.setVertexCoord(2, CVector((float) (_X + _W), 0, (float) (_Y + _H) ) ); vb.setVertexCoord(3, CVector(0 , 0, (float) (_Y + _H) ) ) ; driver->setupViewMatrix(CMatrix::Identity) ; driver->setupModelMatrix(CMatrix::Identity) ; driver->activeVertexBuffer(vb) ; driver->renderQuads(mbMat, 0, 1) ; // blit back frame buffer to save this frame driver->copyFrameBufferToTexture(_Tex, 0, 0, 0, _X, _Y, _W, _H) ; }

void NL3D::CMotionBlur::releaseMotionBlur (   )

release the resources used by motion blur Definition at line 56 of file motion_blur.cpp. References _H, and _W. { _Tex = NULL ; _X = _Y = _W = _H = 0 ; }

void NL3D::CMotionBlur::startMotionBlur (  uint  x, uint  y, uint  width, uint  height )

Must be called before performing motion blur on a image sequence. Motion blur is performed on a rectangular area. 2 calls -> nlassert. Once motion blur must be stopped, you must call releaseMotionBlur. Parameters: x  the x position of the top-left coener of the rectangle on which motion blur apply y  the y position of the top-left coener of the rectangle on which motion blur apply width  the width of the rectangle on which motion blur apply height  the height of the rectangle on which motion blur apply Definition at line 45 of file motion_blur.cpp. References _H, _W, height, nlassert, uint, width, x, and y. { nlassert(width > 0 && height > 0) ; _X = x ; _Y = y ; _W = width ; _H = height ; _Tex = new CTextureBlank ; _Tex->resize(NLMISC::raiseToNextPowerOf2(width), NLMISC::raiseToNextPowerOf2(height)) ; }

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Field Documentation

uint NL3D::CMotionBlur::_H [protected]

Definition at line 73 of file motion_blur.h. Referenced by performMotionBlur(), releaseMotionBlur(), and startMotionBlur().

NLMISC::CSmartPtr<ITexture> NL3D::CMotionBlur::_Tex [protected]

Definition at line 72 of file motion_blur.h.

uint NL3D::CMotionBlur::_W [protected]

Definition at line 73 of file motion_blur.h. Referenced by performMotionBlur(), releaseMotionBlur(), and startMotionBlur().

uint NL3D::CMotionBlur::_X [protected]

Definition at line 73 of file motion_blur.h.

uint NL3D::CMotionBlur::_Y [protected]

Definition at line 73 of file motion_blur.h.

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

• motion_blur.h
• motion_blur.cpp

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