基于Irrlicht引擎的3D游戏实例v0.7

这一版实现了某大型游戏的第一人称视角UI，包括以下功能：

- WS前进后退

- AD左右转向

- 鼠标左键控制视角旋转

- 鼠标右键控制物体旋转

- 鼠标滚轮控制视距

还加入了简单爆炸效果和音效播放。

附上第一人称视角主要代码：

//! animates a scene node
void CSceneNodeAnimatorMagicFPS::animateNode(ISceneNode* node, u32 timeMs)
{
bool bTargetNeedUpdate = false;
bool bRotNeedUpdate = false;
if (!node)
return;

if(FirstUpdate)
{
if (CursorControl )
{
CursorControl->setPosition(0.5f, 0.5f);
CursorPos = LastCursorPos = CursorControl->getRelativePosition();
}
LastAnimationTime = StartTime;
FirstUpdate = false;
}
u32 diffTime = timeMs - LastAnimationTime;
if (diffTime != 0)
{
if(bWindowActive) animateMouseMove();

updateRotateSpeed();

core::vector3df oldObjRot = node->getRotation();
core::vector3df newObjRot = oldObjRot;
core::vector3df oldObjPos = node->getPosition();
core::vector3df newObjPos = oldObjPos;
if( MovingRotateSpeed != core::vector3df(0,0,0) )
{
newObjRot += MovingRotateSpeed;
newObjRot = rotationMod(newObjRot);
node->setRotation(newObjRot);
updateDirection(newObjRot);
}

updateMovingStraightDiret();

core::vector3df rel = MovingStraightDiret * diffTime * StraightSpeed;
newObjPos += rel;
node->setPosition(newObjPos);
// move the camema, current version doesn't change 'Y'
if(Camera)
{
core::vector3df oldCameraPos = Camera->getPosition();
core::vector3df newCameraPos = oldCameraPos;
core::vector3df oldCameraRot = Camera->getRotation();
core::vector3df newCameraRot = oldCameraRot;
core::vector3df oldTarget = Camera->getTarget();
core::vector3df newTarget = oldTarget;

{
bTargetNeedUpdate = true;
bRotNeedUpdate = true;
//! update camera position
/* if( !KeyMouseMagicStatus.S_mouse_down_right )
{
if(newObjPos.Y > -90 && newObjRot.Y < 90)
{
newCameraPos.X = newObjPos.X - Distance * sin(newObjRot.Y / 180.0 * M_PI);
newCameraPos.Z = newObjPos.Z - Distance * cos(newObjRot.Y / 180.0 * M_PI);
}
else
{
newCameraPos.X = newObjPos.X - Distance * sin((180.0 - newObjRot.Y) / 180.0 * M_PI);
newCameraPos.Z = newObjPos.Z + Distance * cos((180.0 - newObjRot.Y) / 180.0 * M_PI);
}
newCameraPos.Y = newObjPos.Y;// + Hight; //deleted 2015/02/16: hight is not nessary for FPS
//? why the point is shaking? because target is not set properly
Camera->setPosition(newCameraPos);
}
else */
if( MovingMagicStatus.S_camara_move_with_mouse )
{
//! right click to reset position and rotation and target
// first, get the rotation of mouse moving
core::vector3df mouseRot;
mouseRot.Y = DiffCursorPos.X * 100; // TODO:Change speed By user input
mouseRot.X = DiffCursorPos.Y * 100; // TODO:Change speed By user input
// fix bug: up/down is also controled by Z
mouseRot.Z = DiffCursorPos.Y * 100; // TODO:Change speed By user input
f32 diffR = DiffCursorPos.Y * (-2); // TODO:Change speed By user input
// fix bug: when up/down, the rotation is changed with face or back of obj and camera
f32 judgeDirection = ( oldObjPos.X - oldCameraPos.X ) * Direction.X + (oldObjPos.Z - oldCameraPos.Z) * Direction.Z;
if( judgeDirection > 0 )
{
// the same direction
mouseRot.X *= -1;
mouseRot.Z *= -1;
}
else if( judgeDirection == 0)
{
// 90 degree
// !!!!!!!!!!!  TODO !!!!!!!!!!!! why the speed near 90 degree is 0?
}
else
{
// the negtive direction
}
// second, update the vector
core::vector3df oldVectorTC = oldCameraPos - oldObjPos;
core::vector3df newVectorTC = oldVectorTC;
//! magic algorithm to caculate x,y,z
{
f32 sin_r0 = oldVectorTC.Y / Distance;
f32 cos_r0 = sqrt( 1 - sin_r0 * sin_r0 );
f32 cos_r = cos( diffR );
f32 sin_r = sin( diffR );
newVectorTC.Y = Distance*( sin_r0*cos_r + cos_r0*sin_r );
f32 alpha;
if( cos_r0 == 0 )
{
alpha = cos_r;
}
else
{
alpha = cos_r - (sin_r0*sin_r)/cos_r0;
}
newVectorTC.X = alpha*oldVectorTC.X;
newVectorTC.Z = alpha*oldVectorTC.Z;
newVectorTC.rotateXZBy( mouseRot.Y );
}
core::vector3df midPoint = (oldVectorTC+newVectorTC)/2;
f32 smallDis = Distance / 20;
if( ( midPoint.Y - Distance >=0 && midPoint.Y - Distance < smallDis )
|| ( midPoint.Y - Distance <=0 && midPoint.Y - Distance > -smallDis )
|| ( midPoint.Y + Distance >=0 && midPoint.Y + Distance < smallDis )
|| ( midPoint.Y + Distance <=0 && midPoint.Y + Distance > -smallDis )
|| ( newVectorTC.Y - Distance >=0 && newVectorTC.Y - Distance < smallDis )
|| ( newVectorTC.Y - Distance <=0 && newVectorTC.Y - Distance > -smallDis )
|| ( newVectorTC.Y + Distance >=0 && newVectorTC.Y + Distance < smallDis )
|| ( newVectorTC.Y + Distance <=0 && newVectorTC.Y + Distance > -smallDis ) )
{
// deal with 90 degree UP/DOWN
newVectorTC = oldVectorTC;
newVectorTC.rotateXZBy( mouseRot.Y );
}
// third, update the pos
resetCameraPosition(node, newVectorTC);

if( KeyMouseMagicStatus.S_mouse_down_right && ( DiffCursorPos.X != 0 || DiffCursorPos.Y != 0 ) )
{
// reset the rotation to match the camara
resetObjRotation(node);
}

bTargetNeedUpdate = false;
bRotNeedUpdate = false;
}
else if( MovingStraightDiret != core::vector3df(0,0,0) || MovingRotateSpeed != core::vector3df(0,0,0) )
{
core::vector3df newVectorTC = core::vector3df(oldCameraPos.X - oldObjPos.X,oldCameraPos.Y - oldObjPos.Y,oldCameraPos.Z - oldObjPos.Z);
if( MovingRotateSpeed != core::vector3df(0,0,0) )
{
newVectorTC.rotateXZBy( -MovingRotateSpeed.Y );
newVectorTC.rotateYZBy( MovingRotateSpeed.X );
}
resetCameraPosition(node, newVectorTC);
}
else if( MovingMagicStatus.S_distance_changed )
{
core::vector3df oldVectorTC = oldCameraPos - oldObjPos;
resetCameraPosition(node, oldVectorTC);
MovingMagicStatus.S_distance_changed = false;
}

//! update camera rotation
}
}
LastAnimationTime = timeMs;
}
}