...wd......wd......wd...實驗一追逐與攔截實驗報告一、實驗目的掌握游戲中追逐與攔截的人工智能算法二、實驗儀器Windows7系統(tǒng)MicrosoftVisualStudio2015三、實驗原理及過程//描述追逐與攔截的算法原理//描述程序實現(xiàn)時的思路包括對每個調用的API進展詳細說明〔1〕描述追逐與攔截的算法原理：連續(xù)環(huán)境中的視線追逐是最簡單的追逐算法，但是追逐者的移動不僅有線速度，而且還有角速度。算法思路就是：首先根據(jù)角速度把方向轉到視線方向，然后向目標追過去。完整追逐/閃躲由三局部組成：首先，作出追或逃的決策判斷。其次，開場追或逃〔本章重點〕最后，避開障礙物。攔截算法的根本原理是可以預測獵物未來的位置，然后直接到那個位置去，讓追擊者和獵物同時到達同一個位置。為了找出追擊者和獵物能同時到達的點，不僅要考慮他們的移動方向，還要考慮他們的速度。〔2〕Main和winmain進展函數(shù)的定義。RigidBody2D類：進展物體的質量，慣性，關系，坐標，長高寬即外形的定義，用向量表示他們移動的方向。UpdateSimulation函數(shù)對于物體1,2的移動進展反響和控制。DoCraft2Chase函數(shù)對于物體1,2追逐進展判斷，DoCraft2Evade函數(shù)對于物體1,2躲避進展判斷。DoCraft2InterceptAlt函數(shù)對于物體1,2攔截進展判斷。DoAttractCraft2函數(shù)判斷是否攻擊。四、實驗結果五、實驗心得(需包括有何缺乏如何改良)我認為目前的追逐與攔截的缺乏之處在于：本次實驗做的是連續(xù)環(huán)境中的視線追逐與攔截。相比磚塊環(huán)境中的追逐與攔截，肯定是要靈活變通很多，但是箭頭老要跑到屏幕外面去，這就非常為難了。獵物的速度向量和初始位置向量是固定的，而且靠攏時間的計算是需要相對位移和相對速度的，容易得到兩者不相遇的為難情況。如何改良：計算采用靠攏時間的方法，此外，再想方法讓箭頭留在屏幕以內，這樣視覺感受會比擬好。六、主要代碼main.cpp#include"main.h"#include"time.h"http://---------------------------------------------------------------------------/*Book:AIforGameDevelopersAuthors:DavidM.Bourg&GlennSeemannExample:Chasingandevadingincontinuousenvironments,Chapter2*///---------------------------------------------------------------------------//GlobalVariables:int FrameCounter=0;RigidBody2D Craft1,Craft2;Vector Target;#define _TIMESTEP 0.001#define _TOL 1e-10#define _FWDTIME 10#define _THRUSTFACTOR 3#define_CHASESETUP truebool Initialize(void){ Craft1.fMass=10; Craft1.fInertia=10; Craft1.fInertiaInverse=1/10; Craft1.vPosition.x=_WINWIDTH-60; Craft1.vPosition.y=_WINHEIGHT*0.8; Craft1.fWidth=10; Craft1.fLength=20; Craft1.fHeight=5; Craft1.fOrientation=135; Craft1.CD.y=-0.12*Craft1.fLength; Craft1.CD.x=0.0f; //coordinatesofthebodycenterofdrag Craft1.CT.y=-0.50*Craft1.fLength; Craft1.CT.x=0.0f; //coordinatesofthepropellerthrustvector Craft1.CPT.y=0.5*Craft1.fLength; Craft1.CPT.x=-0.5*Craft1.fWidth; //coordinatesoftheportbowthruster Craft1.CST.y=0.5*Craft1.fLength; Craft1.CST.x=0.5*Craft1.fWidth; //coordinatesofthestarboardbowthruster Craft1.ProjectedArea=(Craft1.fLength+Craft1.fWidth)*Craft1.fHeight; Craft1.ThrustForce=_THRUSTFORCE*1; Craft2.fMass=10; Craft2.fInertia=10; Craft2.fInertiaInverse=1/10; if(_CHASESETUP) { Craft2.vPosition.x=40; Craft2.vPosition.y=_WINHEIGHT*0.8; }else{ Craft2.vPosition.x=Craft1.vPosition.x-Craft1.fLength*8; Craft2.vPosition.y=Craft1.vPosition.y-Craft1.fLength*4; } Craft2.fWidth=10; Craft2.fLength=20; Craft2.fHeight=5; if(_CHASESETUP) Craft2.fOrientation=-135; else Craft2.fOrientation=135; Craft2.CD.y=-0.12*Craft2.fLength; Craft2.CD.x=0.0f; //coordinatesofthebodycenterofdrag Craft2.CT.y=-0.50*Craft2.fLength; Craft2.CT.x=0.0f; //coordinatesofthepropellerthrustvector Craft2.CPT.y=0.5*Craft2.fLength; Craft2.CPT.x=0.5*Craft2.fWidth; //coordinatesoftheportbowthruster Craft2.CST.y=0.5*Craft2.fLength; Craft2.CST.x=-0.5*Craft2.fWidth; //coordinatesofthestarboardbowthruster Craft2.ProjectedArea=(Craft2.fLength+Craft2.fWidth)*Craft2.fHeight; Craft2.ThrustForce=_THRUSTFORCE*_THRUSTFACTOR; returntrue;}void UpdateSimulation(void){ double dt=_TIMESTEP; RECT r; Craft1.SetThrusters(false,false); if(IsKeyDown(VK_UP)) Craft1.ModulateThrust(true); if(IsKeyDown(VK_DOWN)) Craft1.ModulateThrust(false); if(IsKeyDown(VK_RIGHT)) Craft1.SetThrusters(true,false); if(IsKeyDown(VK_LEFT)) Craft1.SetThrusters(false,true); //Docraft2AI Craft2.Fa.x=0; Craft2.Fa.y=0; Craft2.Pa.x=0; Craft2.Pa.y=0; if(BasicChase) { DoCraft2Chase(); DoCraft2ModulateThrust(); } if(BasicEvade) DoCraft2Evade(); if(InterceptChase) { //DoCraft2Intercept(); //DoCraft2ModulateThrust(); DoCraft2InterceptAlt(); } if(PotentialChase) DoAttractCraft2(); //updatethesimulation Craft1.UpdateBodyEuler(dt); Craft2.UpdateBodyEuler(dt); if(FrameCounter>=_RENDER_FRAME_COUNT) { //updatethedisplay if(!ShowTrails) ClearBackBuffer(); DrawCraft(Craft1,RGB(0,0,255)); DrawCraft(Craft2,RGB(255,0,0)); RECT r; r.left=(int)(Target.x-3); r.top=(int)(Target.y-3); r.right=(int)(Target.x+3); r.bottom=(int)(Target.y+3); DrawEllipse(&r,1,RGB(0,255,0)); CopyBackBufferToWindow(); FrameCounter=0; }else FrameCounter++; if(Craft1.vPosition.x>_WINWIDTH)Craft1.vPosition.x=0; if(Craft1.vPosition.x<0)Craft1.vPosition.x=_WINWIDTH; if(Craft1.vPosition.y>_WINHEIGHT)Craft1.vPosition.y=0; if(Craft1.vPosition.y<0)Craft1.vPosition.y=_WINHEIGHT; if(Craft2.vPosition.x>_WINWIDTH)Craft2.vPosition.x=0; if(Craft2.vPosition.x<0)Craft2.vPosition.x=_WINWIDTH; if(Craft2.vPosition.y>_WINHEIGHT)Craft2.vPosition.y=0; if(Craft2.vPosition.y<0)Craft2.vPosition.y=_WINHEIGHT;}void DrawCraft(RigidBody2D craft,COLORREFclr){ Vector vList[5]; double wd,lg; int i; Vector v1; wd=craft.fWidth; lg=craft.fLength; vList[0].y=lg/2; vList[0].x=wd/2; vList[1].y=-lg/2; vList[1].x=wd/2; vList[2].y=-lg/2; vList[2].x=-wd/2; vList[3].y=lg/2; vList[3].x=-wd/2; vList[4].y=lg/2*1.5;vList[4].x=0; for(i=0;i<5;i++) { v1=VRotate2D(craft.fOrientation,vList[i]); vList[i]=v1+craft.vPosition; } DrawLine(vList[0].x,vList[0].y,vList[1].x,vList[1].y,2,clr); DrawLine(vList[1].x,vList[1].y,vList[2].x,vList[2].y,2,clr); DrawLine(vList[2].x,vList[2].y,vList[3].x,vList[3].y,2,clr); DrawLine(vList[3].x,vList[3].y,vList[4].x,vList[4].y,2,clr); DrawLine(vList[4].x,vList[4].y,vList[0].x,vList[0].y,2,clr); if(ShowVectors) { Vector v,u; double f=5; //Showvelocityvectorsingreen DrawLine(craft.vPosition.x,craft.vPosition.y,craft.vPosition.x+craft.vVelocity.x,craft.vPosition.y+craft.vVelocity.y,3,RGB(0,255,0)); //Showforcevectorsinblack //thrustvector v.x=0; v.y=craft.ThrustForce*f; v=VRotate2D(craft.fOrientation,v); u.x=craft.CT.x; u.y=craft.CT.y; u=VRotate2D(craft.fOrientation,u); DrawLine(craft.vPosition.x+u.x,craft.vPosition.y+u.y,craft.vPosition.x+u.x+v.x,craft.vPosition.y+u.y+v.y,1,RGB(0,0,0)); //portsteeringforce v.x=craft.PThrust.x*f; v.y=craft.PThrust.y*f; v=VRotate2D(craft.fOrientation,v); u.x=craft.CPT.x; u.y=craft.CPT.y; u=VRotate2D(craft.fOrientation,u); DrawLine(craft.vPosition.x+u.x,craft.vPosition.y+u.y,craft.vPosition.x+u.x+v.x,craft.vPosition.y+u.y+v.y,1,RGB(0,0,0)); //stbdsteeringforce v.x=craft.SThrust.x*f; v.y=craft.SThrust.y*f; v=VRotate2D(craft.fOrientation,v); u.x=craft.CST.x; u.y=craft.CST.y; u=VRotate2D(craft.fOrientation,u); DrawLine(craft.vPosition.x+u.x,craft.vPosition.y+u.y,craft.vPosition.x+u.x+v.x,craft.vPosition.y+u.y+v.y,1,RGB(0,0,0)); //appliedforce v.x=craft.Fa.x*f; v.y=craft.Fa.y*f; v=VRotate2D(craft.fOrientation,v); u.x=craft.Pa.x; u.y=craft.Pa.y; u=VRotate2D(craft.fOrientation,u); DrawLine(craft.vPosition.x+u.x,craft.vPosition.y+u.y,craft.vPosition.x+u.x+v.x,craft.vPosition.y+u.y+v.y,1,RGB(0,0,0)); }}void DoCraft2Chase(void){ Vector u,v; bool p=false; bool s=false; u=VRotate2D(-Craft2.fOrientation,(Craft1.vPosition-Craft2.vPosition)); u.Normalize(); Target=Craft1.vPosition; if(u.x<-_TOL) p=true; elseif(u.x>_TOL) s=true; Craft2.SetThrusters(p,s);}void DoCraft2Evade(void){ Vector u,v; bool p=false; bool s=false; u=VRotate2D(-Craft2.fOrientation,(Craft1.vPosition-Craft2.vPosition)); u.Normalize(); if(u.x>0) p=true; elseif(u.x<0) s=true; Craft2.SetThrusters(p,s); Target=Craft2.vPosition;}void DoCraft2Intercept(void){ Vector u1,u2,u; Vector s1,s2; VectorVr; double t1,t2; Vector s1unit,s2unit; bool p=false; bool s=false; Vr=Craft1.vVelocity-Craft2.vVelocity; s2=GetVelocityIntersection()-Craft2.vPosition; s2unit=s2; s2unit.Normalize(); u2=VRotate2D(-Craft2.fOrientation,s2); t2=s2.Magnitude()/(Vr*s2unit); s1=Craft1.vPosition-Craft2.vPosition; s1unit=s1; s1unit.Normalize(); u1=VRotate2D(-Craft2.fOrientation,s1); t1=s1.Magnitude()/(Vr*s1unit); if(t1<0.0) { u=u2; Target=s2+Craft2.vPosition; }elseif(t2<0.0){ u=u1; Target=s1+Craft2.vPosition; }elseif(t2<t1) { u=u2; Target=s2+Craft2.vPosition; }else{ u=u1; Target=s1+Craft2.vPosition; } u.Normalize(); if(u.x<-_TOL) p=true; elseif(u.x>_TOL) s=true; Craft2.SetThrusters(p,s);}void DoCraft2InterceptAlt(void){ Vector u; Vector s1,s2,s12; bool p=false; bool s=false; double tClose; Vector Vr12; double vr; //turnaroundifwegetaheadoftheprey... s12=Craft1.vPosition-Craft2.vPosition; u=VRotate2D(-Craft2.fOrientation,s12); if(u.y<-_TOL) { //if(GetRandomNumber(0,10,true)<5) p=true; //else // s=true; Craft2.SetThrusters(p,s); Target=Craft2.vPosition; return; } Vr12=Craft1.vVelocity-Craft2.vVelocity;//closingvelocity s12=Craft1.vPosition-Craft2.vPosition;//rangetoclose tClose=s12.Magnitude()/Vr12.Magnitude();//timetoclose s1=Craft1.vPosition+(Craft1.vVelocity*tClose); Target=s1; s2=s1-Craft2.vPosition; u=VRotate2D(-Craft2.fOrientation,s2); u.Normalize(); if(u.x<-_TOL) p=true; elseif(u.x>_TOL) s=true; Craft2.SetThrusters(p,s);}void DoAttractCraft2(void){ //ApplyLenard-JonespotentialforcetoCraft2 Vector r=Craft2.vPosition-Craft1.vPosition; Vectoru=r; u.Normalize(); doubleU,A,B,n,m,d; A=2000; B=4000; n=2; m=3; d=r.Magnitude()/Craft2.fLength; U=-A/pow(d,n)+B/pow(d,m); Craft2.Fa=VRotate2D(-Craft2.fOrientation,U*u); Craft2.Pa.x=0; Craft2.Pa.y=Craft2.fLength/2; Target=Craft1.vPosition;}Vector GetVelocityIntersection(void){ doubles,t,num,denom; Vector a,b,c,d; a=Craft1.vPosition; b=a+Craft1.vVelocity; c=Craft2.vPosition; d=c+Craft2.vVelocity; denom=a.x*(d.y-c.y)+ b.x*(c.y-d.y)+ d.x*(b.y-a.y)+ c.x*(a.y-b.y); if(denom==0) returnVector(a.x,a.y,0); num= a.x*(d.y-c.y)+ c.x*(a.y-d.y)+ d.x*(c.y-a.y); s=num/denom; num= -(a.x*(c.y-b.y)+ b.x*(a.y-c.y)+ c.x*(b.y-a.y)); t=num/denom; if((s>=0)&&(t>=0)) returnVector(a.x+s*(b.x-a.x),a.y+s*(b.y-a.y),0); else returnVector(a.x,a.y,0);}intGetRandomNumber(intmin,intmax,boolseed){ int number; if(seed) srand((unsigned)time(NULL));number=(((abs(rand())%(max-min+1))+min));if(number>max) number=max;if(number<min) number=min; returnnumber;}void DoCraft2ModulateThrust(void){ Vector r=Craft1.vPosition-Craft2.vPosition; double dmax=Craft2.fLength*10; if((Craft2.PThrust.Magnitude()>0)||(Craft2.SThrust.Magnitude()>0))//turning { if(r.Magnitude()>dmax) Craft2.ThrustForce=_MAXTHRUST; else Craft2.ThrustForce=r.Magnitude()/dmax*_MAXTHRUST; }else{ //todo:checkhowclosewearetotargetandadjustspeedtostaywithit Craft2.ThrustForce=_MAXTHRUST; }}RigidBody2D.cpp#include"RigidBody2D.h"RigidBody2D::RigidBody2D(void){}voidRigidBody2D::CalcLoads(void){Vector Fb; //storesthesumofforcesVector Mb; //storesthesumofmomentsVector Thrust; //thrustvector//resetforcesandmoments: vForces.x=0.0f; vForces.y=0.0f; vForces.z=0.0f; //alwayszeroin2D vMoment.x=0.0f; //alwayszeroin2D vMoment.y=0.0f; //alwayszeroin2D vMoment.z=0.0f; Fb.x=0.0f; Fb.y=0.0f; Fb.z=0.0f; Mb.x=0.0f; Mb.y=0.0f; Mb.z=0.0f;//Definethethrustvector,whichactsthroughthecraft'sCG Thrust.x=0.0f; Thrust.y=1.0f; Thrust.z=0.0f;//zeroin2D Thrust*=ThrustForce;//Calculateforcesandmomentsinbodyspace:Vector vLocalVelocity;float fLocalSpeed;Vector vDragVector; float tmp;Vector vResultant; Vector vtmp; //Calculatetheaerodynamicdragforce://Calculatelocalvelocity://Thelocalvelocityincludesthevelocityduetolinearmotionofthecraft,//plusthevelocityateachelementduetotherotationofthecraft. vtmp=vAngularVelocity^CD;//rotationalpart vLocalVelocity=vVelocityBody+vtmp;//Calculatelocalairspeed fLocalSpeed=vLocalVelocity.Magnitude();//Findthedirectioninwhichdragwillact.//Dragalwaysactsinlinewiththerelativevelocitybutintheopposingdirectionif(fLocalSpeed>tol) { vLocalVelocity.Normalize(); vDragVector=-vLocalVelocity; //Determinetheresultantforceontheelement.doublef;if((Thrust*vLocalVelocity)/(Thrust.Magnitude()*vLocalVelocity.Magnitude())>0) f=2; else f=1; tmp=0.5f*rho*fLocalSpeed*fLocalSpeed*ProjectedArea*f; vResultant=vDragVector*_LINEARDRAGCOEFFICIENT*tmp;//simulatefuselagedrag//Keeparunningtotaloftheseresultantforces(totalforce) Fb+=vResultant;//CalculatethemomentabouttheCGofthiselement'sforce//andkeeparunningtotalofthesemoments(totalmoment) vtmp=CD^vResultant; Mb+=vtmp; }//CalculatethePort&Starboardbowthrusterforces://Keeparunningtotaloftheseresultantforces(totalforce) Fb+=3*PThrust;//CalculatethemomentabouttheCGofthiselement'sforce//andkeeparunningtotalofthesemoments(totalmoment) vtmp=CPT^PThrust; Mb+=vtmp;//Keeparunningtotaloftheseresultantforces(totalforce) Fb+=3*SThrust;//CalculatethemomentabouttheCGofthiselement'sforce//andkeeparunningtotalofthesemoments(totalmoment) vtmp=CST^SThrust; Mb+=vtmp;//dootherappliedforceshere Fb+=Fa; vtmp=Pa^Fa; Mb+=vtmp;//Calculaterotationaldragif(vAngularVelocity.Magnitude()>tol) { vtmp.x=0; vtmp.y=0; tmp=0.5f*rho*vAngularVelocity.z*vAngularVelocity.z*