User interactive animation in matlab - matlab

Question

I am trying to make a user interactive animation in matlab. It is a square that translates and rotates across the screen and the user has to click on it. If they click on it, they will receive points and the animation will repeat. If they click on the whitespace (eg. anywhere except within the square) The animation will exit and YOU LOSE will be displayed. I have the animation almost finished using two functions. One to create the animation and another that registers the mouse click. So far I can recognize the mouse click and the animation will stop if the user clicks on the whitespace but the animation will not repeat if the user clicks within the polygon. I am unsure how to modify my code so that the animation will repeat until the user clicks the white space. I have pasted my code below. Any help would be greatly appreciated.
Animation function:
function movingPolygon
global gUserHitPolygon;
global gCurrentXVertices;
global gCurrentYVertices;
gUserHitPolygon = true;
nSides =4;
%Polar points
r=1;
theta = pi/nSides * (1:2:2*nSides-1);
%Cartesisn points
x0 = r * cos(theta);
y0 = r * sin(theta);
nFrames = 100;
xx = linspace(0,10, nFrames);
yy = xx;
rr = linspace(0, 2*pi, nFrames);
h = figure;
set(h,'WindowButtonDownFcn', #mouseDownCallback);
for i = 1:nFrames
rX = [cos(rr(i)), -sin(rr(i))];
rY = [sin(rr(i)), cos(rr(i))];
x1 = rX * [x0; y0];
y1 = rY * [x0; y0];
x2= x1 + xx(i);
y2= y1 + yy(i);
gCurrentXVertices=x2;
gCurrentYVertices=y2;
y=fill(x2, y2, 'b');
xlim([0,10]); ylim([0,10]);
hold on;
pause(0.000000003);
if ~gUserHitPolygon
clear GLOBAL gUserHitPolygon gCurrentXVertices gCurrentYVertices;
break;
end
delete(y);
end
end
Callback Function:
function mouseDownCallback(~,~)
global UserHitPolygon;
global CurrentXVertices;
global CurrentYVertices;
xVertices = gCurrentXVertices;
yVertices = gCurrentYVertices;
% if we have valid (so non-empty) sets of x- and y-vertices then...
if ~isempty(xVertices) && ~isempty(yVertices)
% get the coordinate on the current axis
coordinates = get(gca,'CurrentPoint');
coordinates = coordinates(1,1:2);
% if the coordinate is not in the polygon, then change the
% flag
if ~inpolygon(coordinates(1),coordinates(2),xVertices,yVertices)
gUserHitPolygon = false;
end
end
end
Edit: fixed some bugs in the callback function.

Answer 1

Short answer
include your animation in a while loop
Long Answer
No matter what a user does, the animation will only play once, because it doesn't know to repeat. The answer to this is to use a while loop, which will repeat your animation until you tell it to stop. Your main loop then becomes
done = false; % your stopping condition
while ~done
for i = 1:nFrames
rX = [cos(rr(i)), -sin(rr(i))];
rY = [sin(rr(i)), cos(rr(i))];
x1 = rX * [x0; y0];
y1 = rY * [x0; y0];
x2= x1 + xx(i);
y2= y1 + yy(i);
gCurrentXVertices=x2;
gCurrentYVertices=y2;
y=fill(x2, y2, 'b');
xlim([0,10]); ylim([0,10]);
hold on;
pause(0.000000003);
if ~gUserHitPolygon
clear GLOBAL gUserHitPolygon gCurrentXVertices gCurrentYVertices;
done = true; % set your stopping condition
break;
end
delete(y);
end
end