www.pudn.com > XFileLoadingCode.zip > Camera.cpp

//************************************************************************************************** 
// 
// Camera.cpp: implementation of the CCamera class. 
// 
// Description: basic 1st person camera - see site for more details 
// 
// Created by: Keith Ditchburn 15/06/01 
// 
//************************************************************************************************** 
#include "dxstdafx.h" 
#include "Camera.h" 
 
/************************************************************************************************** 
**************************************************************************************************/ 
CCamera::CCamera() 
{ 
	// Set member variable defaults 
	m_movementSpeed = 0.3f; 
	m_rotationSpeed = 0.009f; 
 
	// Start position 
	m_position=D3DXVECTOR3(0.0f,2.0f,-4.0f); 
	m_look=D3DXVECTOR3(0.0f,0.0f,1.0f); 
	m_right=D3DXVECTOR3(1.0f,0.0f,0.0f); 
	m_up=D3DXVECTOR3(0.0f,1.0f,0.0f); 
	m_rotationChange=D3DXVECTOR3(0.0f,0.0f,0.0f); 
} 
 
/************************************************************************************************** 
**************************************************************************************************/ 
CCamera::~CCamera() 
{ 
 
} 
 
/************************************************************************************************** 
Desc: Create view matrix 
Date: 24/02/00 
**************************************************************************************************/ 
void CCamera::CalculateViewMatrix(D3DXMATRIX *view)  
{ 
	assert(view); 
 
	BaseRegenerateVectors(); 
 
	// If we want to simulate YAW we must Create a Matrix that rotates around the Cameras UP vector 
	D3DXMATRIX YawMatrix; 
	D3DXMatrixRotationAxis(& YawMatrix, &m_up, m_rotationChange.y);  
 
	// Next, if we need to simulate Pitch, we now Create a Matrix that rotates around the Camera RIGHT vector 
	D3DXMATRIX PitchMatrix; 
	D3DXMatrixRotationAxis(& PitchMatrix, &m_right, m_rotationChange.x );  
 
	// To apply the 'Yaw' we rotate the LOOK & RIGHT Vectors about the UP Vector (YawMatrix) 
	D3DXVec3TransformCoord(&m_look , &m_look, &YawMatrix);  
	D3DXVec3TransformCoord(&m_right, &m_right, &YawMatrix);  
	 
	// And then we rotate the LOOK & UP Vectors about the RIGHT Vector (PitchMatrix)  
	D3DXVec3TransformCoord(&m_look , &m_look, & PitchMatrix);  
	D3DXVec3TransformCoord(&m_up, &m_up, & PitchMatrix);  
 
	// Now set up the View Matrix 
	D3DXMatrixIdentity(view); 
	 
	view->_11 = m_right.x; view->_12 = m_up.x; view->_13 = m_look.x; 
	view->_21 = m_right.y; view->_22 = m_up.y; view->_23 = m_look.y; 
	view->_31 = m_right.z; view->_32 = m_up.z; view->_33 = m_look.z; 
	 
	view->_41 = - D3DXVec3Dot( &m_position, &m_right );  
	view->_42 = - D3DXVec3Dot( &m_position, &m_up ); 
	view->_43 = - D3DXVec3Dot( &m_position, &m_look ); 
 
	// Reset rotations 
	m_rotationChange.x=0.0f; 
	m_rotationChange.y=0.0f; 
	m_rotationChange.z=0.0f; 
 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 24/02/00 
**************************************************************************************************/ 
void CCamera::MoveUp() 
{ 
	m_position+=(m_up*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 24/02/00 
**************************************************************************************************/ 
void CCamera::MoveDown() 
{ 
	m_position-=(m_up*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::MoveForward() 
{ 
	m_position+=(m_look*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::MoveBack() 
{ 
	m_position-=(m_look*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::MoveLeft() 
{ 
	m_position+=(-m_right*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter position 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::MoveRight() 
{ 
	m_position+=(m_right*m_movementSpeed); 
} 
 
/************************************************************************************************** 
Desc: Alter rotation 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::RotateLeft() 
{ 
	m_rotationChange.y=-m_rotationSpeed; 
} 
 
/************************************************************************************************** 
Desc: Alter rotation 
Date: 15/06/01 
**************************************************************************************************/ 
void CCamera::RotateRight() 
{ 
	m_rotationChange.y=m_rotationSpeed; 
} 
 
/************************************************************************************************** 
Desc: Mouse has moved, change into a rotation 
Date: 24/02/00 
**************************************************************************************************/ 
void CCamera::MouseMove(int dx,int dy) 
{ 
	// note: mouse screen movement of 30 is about maximum, so scale accordingly	 
	m_rotationChange.y=m_rotationSpeed*dx*0.5f; 
	m_rotationChange.x=m_rotationSpeed*dy*0.5f;	 
} 
 
/************************************************************************************************** 
Desc: rotation inacuracies can cause matrix to lose its 'axis' shape so regenerate 
Date: 08/03/2002 
**************************************************************************************************/ 
void CCamera::BaseRegenerateVectors() 
{ 
	D3DXVec3Normalize(&m_look,&m_look); 
 
	// Fix it so we are always upright, No roll. 
	m_up   = D3DXVECTOR3( 0.0f, 1.0f,0.0f ); 
 
	D3DXVec3Cross(&m_right,&m_up,&m_look); 
 
	D3DXVec3Normalize(&m_right,&m_right); 
 
	D3DXVec3Cross(&m_up,&m_look,&m_right); 
 
	D3DXVec3Normalize(&m_up,&m_up); 
} 
 
/************************************************************************************************** 
Desc: Set position and view direction 
Date: 28/07/2002 
**************************************************************************************************/ 
void CCamera::SetView(const D3DXVECTOR3 &pos,const D3DXVECTOR3 &look) 
{ 
	m_movementSpeed = 0.3f; 
	m_rotationSpeed = 0.009f; 
 
	m_position=pos; 
	m_look=look; 
 
	BaseRegenerateVectors(); 
 
	m_rotationChange=D3DXVECTOR3( 0.0f, 0.0f,0.0f ); 
} 
 
/************************************************************************************************** 
Desc: allows camera position to be altered 
Date: 15/03/2003 
**************************************************************************************************/ 
void CCamera::SetPosition(const D3DXVECTOR3 &pos) 
{ 
	m_position=pos; 
 
	BaseRegenerateVectors(); 
}