Deleting plotted image from a figure if conditions are met

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Hi, I am trying to make a game where one progresses vertically upwards by bouncing off platforms and the platforms underneath disappear once they are off the screen. I reckon this should be done by deleting them from the plot, but I don't know how to do this. This is my platform generating loop which makes 50 random platforms:
%Generate platform field
xpf = [];
ypf = [];
platformrecord = [];
for n = 1:1:50
hold on
xpf = [xpf randi(512)];
ypf = [ypf randi(30)];
platformcentre = [xpf(n) ypf(n)+70*(n-1)];
pfgen(48,16);
end
where pfgen() draws the platform image out of a random selection of 4 images, as below
function pfgen(x,y)
%generates a platform at specified x and y coordinates.
global platformcentre
n = randi(4);
d = randi(2);
platforms = [".\Assets\art\bin\simpleplatform-48x16-v1.png"...
".\Assets\art\bin\simpleplatform-48x16-v2.png"...
".\Assets\art\bin\simpleplatform-48x16-v3.png"...
".\Assets\art\bin\simpleplatform-48x16-v4.png"
];
if d == 1
[pfimage, map, alphachannel] = imread(platforms(n));
imagesc('XData',[platformcentre(1)-x/2 platformcentre(1)+x/2], ...
'YData',[platformcentre(2)-y/2 platformcentre(2)+y/2], ...
'CData',flip(pfimage,1), ...
'AlphaData',flip(alphachannel,1));
else
[pfimage, map, alphachannel] = imread(platforms(n));
pfimage = flip(pfimage,1);
alphachannel = flip(alphachannel,1);
imagesc('XData',[platformcentre(1)-x/2 platformcentre(1)+x/2], ...
'YData',[platformcentre(2)-y/2 platformcentre(2)+y/2], ...
'CData',flip(pfimage,2), ...
'AlphaData',flip(alphachannel,2));
end
Is there a way to say if the y-coordinate of my platform is less than the lowest y-coordinate visible, to remove said platform from the plot? Thanks.

Accepted Answer

Philippe Lebel
Philippe Lebel on 11 Dec 2019
Edited: Philippe Lebel on 11 Dec 2019
If you get the handle of the plot like so:
h = plot(1,1,'Xr')
you can just delete the handle and the data disapears
delete(h)
like wise for imagesc you can do:
doge = true;
h = imagesc
% wow such image
% very pixel
if doge
delete(h)
end
% such blank
% many empty
  1 Comment
Daniel Goh
Daniel Goh on 12 Dec 2019
Ah, thank you, this works! I did not know that deleting the handle deletes the plot.

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