Show Posts
211
General / Re: C++ SFML, Circular Movement - Help!
« on: September 19, 2013, 04:45:16 am »
you can convert degrees to radians by :
radians = degrees * PI / 180.0
and if i m not wrong, the paddle s absolute position would be, as zsbzsb said, but adding it to the center of the circle:
paddle.Position = new Vector2f( cos(angle) * radius + 320, sin(angle) * radius + 240 );
where 320,240 would be the center of the circle, from where its radius moves the paddle, ... actually, the paddle s angle is taken between the segments from the center of the circle to the center of the paddle, and from the center to the paddle s origin point
another matter:
you would have to get the angle of the ball, including when it touches the paddle, or the circunpherence:
first you should give and initial angle to the ball, por example, 60 degrees
when it bounces with any ot the 2 paddles,
ballAngle = 180 - 2 * paddleAngle - ballAngle;
while (ballAngle < 0) ballAngle += 360;
when the ball bounces with the circunpherence:
i see the circunpherence as a great polygon, as if it had too many edges, then we would have to get the angle of that edge or segment where the ball hits, and apply the same formula (as if the edges were static paddles):
let s suppose we have the (xHit, yHit) Point of where the ball hit. That point belongs to the circunpherence.
the angle would be:
angleCirc = ASin( (yHit - 240) / radius ) + PI / 2; // this angle is already in radians
ASin is the function that returns the angle whose sine is x. Here the only way to get the angle is getting the Sine, that is Y / radius. Adding PI /2 (that is 90 degrees) is because the edge is normal to the radius
then when the ball bounces with the circle line, the new ball angle could be:
ballAngle = 180 - 2 * angleCirc - ballAngle; // remember angleCirc is already in radians
Perhaps you will need to detect in every loop if the ball hits weather the circle wall or a paddle. I suppose you will need the trigonometrical functions again ...
please let us know if you need more help ...
I agree with zsbzsb ... it s very nice your idea, very original ... I won t steal it, cos i m very busy with my poor Sonic ... then, when you finish the game, please post the link to it
the last thing: don t you forget the goal lines?
I hope it helps
... and also hope i m not wrong, i haven t tested it ... just into my mind 
Pablo
(from Bs As Argentina)
radians = degrees * PI / 180.0
and if i m not wrong, the paddle s absolute position would be, as zsbzsb said, but adding it to the center of the circle:
paddle.Position = new Vector2f( cos(angle) * radius + 320, sin(angle) * radius + 240 );
where 320,240 would be the center of the circle, from where its radius moves the paddle, ... actually, the paddle s angle is taken between the segments from the center of the circle to the center of the paddle, and from the center to the paddle s origin point
another matter:
you would have to get the angle of the ball, including when it touches the paddle, or the circunpherence:
first you should give and initial angle to the ball, por example, 60 degrees
when it bounces with any ot the 2 paddles,
ballAngle = 180 - 2 * paddleAngle - ballAngle;
while (ballAngle < 0) ballAngle += 360;
when the ball bounces with the circunpherence:
i see the circunpherence as a great polygon, as if it had too many edges, then we would have to get the angle of that edge or segment where the ball hits, and apply the same formula (as if the edges were static paddles):
let s suppose we have the (xHit, yHit) Point of where the ball hit. That point belongs to the circunpherence.
the angle would be:
angleCirc = ASin( (yHit - 240) / radius ) + PI / 2; // this angle is already in radians
ASin is the function that returns the angle whose sine is x. Here the only way to get the angle is getting the Sine, that is Y / radius. Adding PI /2 (that is 90 degrees) is because the edge is normal to the radius
then when the ball bounces with the circle line, the new ball angle could be:
ballAngle = 180 - 2 * angleCirc - ballAngle; // remember angleCirc is already in radians
Perhaps you will need to detect in every loop if the ball hits weather the circle wall or a paddle. I suppose you will need the trigonometrical functions again ...
please let us know if you need more help ...
I agree with zsbzsb ... it s very nice your idea, very original ... I won t steal it, cos i m very busy with my poor Sonic ... then, when you finish the game, please post the link to it
the last thing: don t you forget the goal lines?
I hope it helps
... and also hope i m not wrong, i haven t tested it ... just into my mind Pablo
(from Bs As Argentina)
are along side the EXE, as it is in the link I gave you in my last thread, ... when you have a little time, if you want you can see it