问题由原始的海报撤销问题打圈计算
嘿所以运行下面的代码我方应该周游了一圈的时候,但有某种问题与计算功能x,y应该根据行进的速度和角度发生移动。
它成功地四处走动,但没有正确的方式。第二和第四象限是倒转的,向内弯曲而不是向外弯曲。
我无法弄清楚问题是什么......任何人都想帮忙?
#include<SFML/Graphics.hpp>
#include<SFML/System.hpp>
#include<cmath>
#include<vector>
# define M_PI 3.14159265358979323846
sf::RenderWindow Window;
template<typename T>
void CalculateMove(T Time, T Speed, T Angle, T& buffX, T& buffY)
{ //Make the degrees positive
if(Angle<0) Angle= 360-Angle;
//determine what quadrant of circle we're in
unsigned int Quadrant= 1;
if(Angle>90) Quadrant= 2;
if(Angle>180) Quadrant= 3;
if(Angle>270) Quadrant= 4;
//anything above 90 would be impossible triangle
Angle= (float)(Angle-(int)Angle)+(float)((int)Angle%90);
// calculates x and y based on angle and Hypotenuse.02433
if((int)Angle!=0){
buffX= sin(Angle/180 * M_PI)/ (1.f/(Speed*Time));
buffY= sin((180-Angle-90)/ 180 * M_PI)/ (1.f/(Speed*Time));}
else{// Movement is a straight line on X or Y axis
if(Quadrant==0 || Quadrant==2) buffX= Speed*Time;
if(Quadrant==1 || Quadrant==4) buffY= Speed*Time;}
//Quadrant Factor (positive or negative movement on the axis)
switch(Quadrant){
case 1: break;
case 2: buffX=-buffX; break;
case 3: buffX=-buffX; buffY=-buffY; break;
case 4: buffY=-buffY; break;}
};
///////////////////////////////////////// Mysprite ////////////////////////////////
class mySprite : public sf::Sprite
{
private:
float velocity;
float angle;
public:
// all the values needed by the base class sprite();
mySprite(
const sf::Image& Img,
const sf::Vector2f& Position = sf::Vector2f(0, 0),
const sf::Vector2f& Scale = sf::Vector2f(1, 1),
float Rotation = 0.f,
const float Angle= 0.f,
const float Velocity= 0.f,
const sf::Color& Col = sf::Color(255, 255, 255, 255)):
Sprite(Img, Position, Scale, Rotation, Col){
angle= Angle;
velocity= Velocity;};
float Velocity(){return velocity;};
void SetVelocity(float newVelocity){velocity=newVelocity;};
float Angle(){return angle;};
void SetAngle(float newAngle){angle=(float)(newAngle-(int)newAngle)+(float)((int)newAngle%360);};
void Update(){
float frameTime= Window.GetFrameTime();
float X=0,Y=0;
CalculateMove(frameTime,velocity,angle,X,Y);
Move(X,-Y);
};
void Accelerate(float PPS){velocity+=PPS;};
void Turn(float degrees){
float test= (float)((angle+degrees)- (int)(angle+degrees)); //TODO: Get rid of these test
float test2=(float)((int)(angle+degrees)%360);
float test3=test+test2;
angle=(float)((angle+degrees)-(int)(angle+degrees))+(float)((int)(angle+degrees)%360);};
void Reflect(float CollAngle){
SetRotation(-GetRotation());
angle=-angle;
//TODO: factor in the collision angle
};
};
int main()
{
Window.Create(sf::VideoMode(800, 600), "Pong! by Griffin Howlett");
sf::Image img;
img.Create(30,50,sf::Color(255,0,0));
mySprite box(img, sf::Vector2f(400,200), sf::Vector2f(1,1), 0, 180, 200);
Window.Display();
for(;;){
Window.Clear();
box.Update();
box.Turn(45.0*Window.GetFrameTime());
Window.Draw(box);
Window.Display();
}
}
所以我可以后来使x和y运动基于象限为负或正位于 – Griffin 2011-06-17 03:19:03
@Griffin,sin(和cos)函数将自动提供适当角度的负数。 – 2011-06-17 03:20:42