Saving animation of projectile motion

Hi there

I'm struggling to find a way of saving three projectiles on the same graph as a video file. I have three for loops for each iteration that looks like this:

  for i1=1:length(Y1(:,1))
        addpoints(curve1,Y1(i1,1),Y1(i1,2));
        drawnow
        pause(0.1)
  end

And then the code that actually saves only a piece of the animation so far is:

 F(i2) = getframe(gcf);
    video = VideoWriter('trajectories.avi', 'MPEG-4');
    open(video) 
    writeVideo(video, F);
    close(video)

Please help, it only saves the last trajectory.

Thanks!

[darova]

Can you please attach your entire script?

[Christo van Rensburg]

Hi, below is the entire script for the function:

function a = animatevid(Y1, Y2, Y3)

curve1 = animatedline('Color','r','Marker','o');

curve2 = animatedline('Color','b','Marker','^');

curve3 = animatedline('Color','g','Marker','*');

set(gca, 'XLim', [0 100], 'YLim', [-1 8]);

grid on, hold on

xlabel('Distance [m]'), ylabel('Height [m]')

title('Dart Trajectories'),

% --- FOR LOOP FOR ANGLE 1 --- %

for i1=1:length(Y1(:,1))

addpoints(curve1,Y1(i1,1),Y1(i1,2));

drawnow

pause(0.1)

end

pause(0.5)

% --- FOR LOOP FOR ANGLE 2 --- %

for i2=1:length(Y2(:,1))

addpoints(curve2,Y2(i2,1),Y2(i2,2));

drawnow

pause(0.1)

end

pause(0.5)

% --- FOR LOOP FOR ANGLE 3 --- %

for i3=1:length(Y3(:,1))

addpoints(curve3,Y3(i3,1),Y3(i3,2));

drawnow

pause(0.05)

end

legend('Angle 1', 'Angle 2', 'Angle 3')

end

Answer 1

[KSSV]

Convert your animation into .gif file:

https://in.mathworks.com/matlabcentral/answers/94495-how-can-i-create-animated-gif-images-in-matlab

[Christo van Rensburg]

I can maybe see how this would help, but how do I apply that to three different for loops instead of one major for loop like in script?

Answer 2

[darova]

Am i correct?

video = VideoWriter('trajectories.avi', 'MPEG-4');
open(video) 

for i1 = 1:n1
    % draw something
    F = getframe;
    writeVideo(video, F);
    pause(0.02);
end
for i2 = 1:n2
    % draw something
    F = getframe;
    writeVideo(video, F);
    pause(0.02);
end
for i3 = 1:n3
    % draw something
    F = getframe;
    writeVideo(video, F);
    pause(0.02);
end

close(video)

Or you want three curves drawing simultaneously?

[Christo van Rensburg]

Hi

No the it plots the three trajectories after each other which is fine. I now get the following error and the mp4-file generated doesn't include the graph axis and legend which I assume has something to do with the error message displayed:

Warning: The video's width and height has been padded to be a multiple

of two as required by the H.264 codec.