Messages

1

Graphics / Re: plotting path of a robot in an obstacle filled environment

« on: September 04, 2012, 06:34:24 pm »

i will definitely give it a thought
thanks a lot for your help

2

Graphics / Re: plotting path of a robot in an obstacle filled environment

« on: September 04, 2012, 05:38:44 pm »

i just realized that I actually went through your tutorial before this post..read it in a hurry though (i was very impatient at that time)  so couldn't understand it properly but i felt the answer lied somewhere there...i will go through it again...and yeah using a vector is a good solution but i was wondering why such a capability (of retaining the current state  of the window) isn't incorporated in this library...it would have been really good

Thanks a lot for your help...i am quite clear about  most of the stuff now 

3

Graphics / Re: plotting path of a robot in an obstacle filled environment

« on: September 04, 2012, 05:16:53 pm »

by setting the limits to the window i would be better able to monitor the motion of my robot...it can traverse anywhere....first quadrant or may be the third quadrant ...if the default mode only has the 1st quadrant to display then it's a problem....if the problem can be solved using views then i will try to look at it in greater depth...i was really tired searching for simple to use libraries all around...sfml seemed to be very user friendly.....and  i am currently going through the documentation...and i really like it

I have one more question though....as you know i need to see the robot traversing the space...that means the window has to update itself after every iteration....but from what i have seen we need to use App.clear() command everytime which means i have to store the previous states of my robot and every time display them again rather than just displaying the current position over the existing window..is there a way of retaining the current state of the window so i can just update it with a new position of the robot?
thnks

4

Graphics / Re: plotting path of a robot in an obstacle filled environment

« on: September 04, 2012, 04:48:39 pm »

Thanks for the reply...what i meant was how to check whether a point lies inside a polygon created using sfml
My polygon would be defined using polygon.addpoint().How should i go abt checking this?
in matlab you have a function inpolygon() that does this job...what abt sfml
i am aware of the methods to check for collision...for eg writing the eqns of lines forming the polygon and then checking the sign of the expression and so on.....the thing is ...isn't there a direct method or function available to do this job?If i have to do this by writing eqns and all then i may as well use a much simpler library like koolplot....there ought to be a better way of doing this

For the window limits part...i want to basically set x and y axes limits...for eg x limit:-100 to 100 and y limit:-150 to 200
i hope you get the point
 

5

Graphics / plotting path of a robot in an obstacle filled environment

« on: September 04, 2012, 01:00:20 pm »

Hi guys!
I am writing code for rrt(rapidly exploring random trees) which is a sampling based motion planning algorithm.I wrote the code in MATLAB but now i am writing it in c++. I am trying to use sfml but I am having problems with it.
Basically this is what I am trying to do:
calculate the position of the robot and plot it.So when the program executes I would be seeing my robot traversing the space and avoiding the obstacles and finally reaching the goal position.This means that window needs to update dynamically retaining te previous state.
Q-1 how to check whether a point lies inside a polygon (this is for obstacle detection)?
Q-2  the default window only works in the first coordinate....how can i deal with negative coordinates? if i try to give position values which are negative then i can't see anything on the window.Does it have to do something with the views?
Q-3 is it even possible to do what i intend to do using sfml?
Thanks a lot