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| #include <iostream>
#include <GL/GLAux.h>
#include <GL/glut.h>
#include <GL/GLU.h>
#include <GL/GL.h>
#pragma comment (lib, "opengl32.lib")
#pragma comment (lib, "glut32.lib")
#pragma comment (lib, "Box2D.lib")
#include <Box2D/Box2D.h>
#include <SDL.h>
const int WIDTH=640;
const int HEIGHT=480;
const float M2P=70;
const float P2M=0.0142;
b2World* world;
SDL_Surface* screen;
void putPixel(SDL_Surface* dest,int x,int y,int r,int g,int b)
{
// std::cout << x << " " << y << std::endl;
if(x>=0 && x<dest->w && y>=0 && y<dest->h)
((Uint32*)dest->pixels)[y*dest->pitch/4+x]=SDL_MapRGB(dest->format,r,g,b);
}
void swapValue(int& a,int& b)
{
int tmp=a;
a=b;
b=tmp;
}
void drawLine(SDL_Surface* dest,int x0,int y0,int x1,int y1)
{
int tmp;
bool step;
step=abs(y1-y0)>abs(x1-x0);
if(step)
{
swapValue(x0,y0);
swapValue(x1,y1);
}
if(x0>x1)
{
swapValue(x1,x0);
swapValue(y1,y0);
}
float error=0.0;
float y=y0;
float roundError=(float)abs(y1-y0)/(x1-x0);
int ystep=(y1>y0 ? 1 : -1);
for(int i=x0;i<x1;i++)
{
if(step)
putPixel(dest,y,i,255,255,255);
else
putPixel(dest,i,y,255,255,255);
error+=roundError;
if(error>=0.5)
{
y+=ystep;
error-=1;
}
}
}
void rotateTranslate(b2Vec2& vector,const b2Vec2& center,float angle)
{
b2Vec2 tmp;
tmp.x=vector.x*cos(angle)-vector.y*sin(angle);
tmp.y=vector.x*sin(angle)+vector.y*cos(angle);
vector=tmp+center;
}
b2Body* addRect(int x,int y,int w,int h,bool dyn=true)
{
b2BodyDef bodydef;
bodydef.position.Set(x*P2M,y*P2M);
if(dyn)
bodydef.type=b2_dynamicBody;
b2Body* body=world->CreateBody(&bodydef);
b2PolygonShape shape;
shape.SetAsBox(P2M*w/2,P2M*h/2);
b2FixtureDef fixturedef;
fixturedef.shape=&shape;
fixturedef.density=1.0;
body->CreateFixture(&fixturedef);
return body;
}
void drawSquare(b2Vec2* points,b2Vec2 center,float angle)
{
for(int i=0;i<4;i++)
drawLine(screen,points[i].x*M2P,points[i].y*M2P,points[(i+1)>3 ? 0 : (i+1)].x*M2P,points[(i+1)>3 ? 0 : (i+1)].y*M2P);
}
void init()
{
world=new b2World(b2Vec2(0.0,9.81));
addRect(WIDTH/2,HEIGHT-50,WIDTH,30,false);
}
void display()
{
SDL_FillRect(screen,NULL,0);
b2Body* tmp=world->GetBodyList();
b2Vec2 points[4];
while(tmp)
{
for(int i=0;i<4;i++)
{
points[i]=((b2PolygonShape*)tmp->GetFixtureList()->GetShape())->GetVertex(i);
rotateTranslate(points[i],tmp->GetWorldCenter(),tmp->GetAngle());
}
drawSquare(points,tmp->GetWorldCenter(),tmp->GetAngle());
tmp=tmp->GetNext();
}
}
int Main(int argc,char** argv)
{
SDL_Init(SDL_INIT_EVERYTHING);
screen=SDL_SetVideoMode(640,480,32,SDL_SWSURFACE);
Uint32 start;
SDL_Event event;
bool running=true;
init();
while(running)
{
start=SDL_GetTicks();
while(SDL_PollEvent(&event))
{
switch(event.type)
{
case SDL_QUIT:
running=false;
break;
case SDL_KEYDOWN:
switch(event.key.keysym.sym)
{
case SDLK_ESCAPE:
running=false;
break;
}
break;
case SDL_MOUSEBUTTONDOWN:
switch(event.button.button)
{
case SDL_BUTTON_LEFT:
addRect(event.button.x,event.button.y,30,10,true);
break;
case SDL_BUTTON_RIGHT:
addRect(event.button.x,event.button.y,10,30,true);
break;
}
}
}
display();
world->Step(1.0/30.0,8,3); //update
SDL_Flip(screen);
if(1000.0/30>SDL_GetTicks()-start)
SDL_Delay(1000.0/30-(SDL_GetTicks()-start));
}
SDL_Quit();
return 0;
} |
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