spin3dplot

classdef spin3dplot
%SPIN3DPLOT Why so stiff? Take a spin!
%   This class allows you to spin your 3D plots.
%   At this time, only mesh and surf are supported.
%   Your SURFACEPLOT object will have a black background by default.
%   This results in your plot automagically turn awesome.
%   If you're boring and stiff, you may disable the black in the
%   constructor method. But you wouldn't do that, would you?
%
%   Side Note: The function is currently effective only on mesh and surf
%   plots. Maybe I'll add in more as time comes. Maybe I'll get distracted
%   whenever I set out on this task. Maybe...

%   Copyright 2013 TAN YU ANG [e-mail] 
%   $Revision: 0.1 $  $Date: 2013/02/28 20:20:20 $
%   Customised function.

properties
        xdata
        ydata
        zdata
        maxidx
        hax
        htimer
    end
    
    methods
        function o = spin3dplot(h,varargin)
        %SPIN3DPLOTX Construct a spin object.
        %
        %    S = SPIN3DPLOT(h) adds a spin to a Surfaceplot graphics
        %    object. It also sprinkles a little bit of awesomeness on you.
        %        
        %    Note that this function only works with the mesh and surf
        %    plots. By default, black mode is set. This means that face
        %    color and background will all be black, making a cool looking
        %    plot. 
        %   
        %    I would make the whole window black, but I'm betting on an
        %    awesome UI from Mathworks in the 2013b release. It might
        %    happen. It might not.
        %
        %    Example:
        %       % To construct a spin object feed in a handle to a surf and
        %       mesh plot:
        %         h = surf(magic(50));
        %         s = spin3dplot(h);
        %       % To begin the fun:
        %         s.start;
        %       % To pause the spin:
        %         s.pause;
        %       % To resume:
        %         s.start;
        %       % To close the graph and remove the timer:
        %         s.stop;
        %

            % Create timer object
            o.htimer = timer('ExecutionMode', 'fixedRate', ...
                'Period', .1, ...
                'UserData', 1);
            
            % Attach plot to object
            o = o.attach(h);

        end
        function o = attach(o,h,varargin)
        %ATTACH Attaches SURFACEPLOT object handle.
        %
        %    ATTACH(handle) attaches the SURFACEPLOT object handle to
        %    SPIN3DPLOT object. This is pre-requisite work for all the
        %    impending awesomeness.
        %
        %            
        
            o.hax = get(h,'Parent');

            % 'Transparent' /Black background
            black = true;
            if (black)
                black = [0 0 0];
                set(h,'FaceColor', black);
                set(h,'EdgeColor', 'interp');
                set(get(get(h,'Parent'),'Parent'),'Color', black)
                set(o.hax,'Color',black);
            else
                set(o.hax,'Color',[0.800000011920929 0.800000011920929 0.800000011920929]);
            end
            
            % Specify camera distance from target to maximum of x and y
            camdist = (abs(get(o.hax,'CameraPosition')));
            dist = max(camdist(1:2));
            
            % Specify point of focus
            center = get(gca,'CameraTarget');
         
            % Define camera trail
            theta = 0:.05:2*pi;
            o.maxidx = length(theta); % trail indexing
            o.xdata = center(1)-dist*sin(theta);
            o.ydata = center(2)- dist*cos(theta);
            o.zdata = camdist(3);

            % Tighten the axes
            dx= reshape(get(get(o.hax,'Children'),'XData'),[],1);
            dy= reshape(get(get(o.hax,'Children'),'YData'),[],1);
            temp = axis;
            axis([min(dx) max(dx) min(dy) max(dy) temp(5) temp(6)]);
            
            set(o.htimer,'TimerFcn', @(v1,v2)(o.step));

            % Fix Camera View Angle
            CameraViewAngle = get(o.hax,'CameraViewAngle');
            set(o.hax,'CameraViewAngle',CameraViewAngle)
            
        end
        function start(o)
        %START Starts spinning
        %
        %    START(o) starts spinning.
        %
        %
        axes(o.hax)
            try
                start(o.htimer)
            end
        end
        function o = step(o)
        %STEP Callback function
        %
        %    STEP(o) is called by the timer object periodically,
        %    incrementing the idx variable. This variable serves as the
        %    index to the position of the viewing camera, and then promptly
        %    refreshes its position.
        %
        %            
            % Increment and update index value
            idx = get(o.htimer,'UserData');
            if idx<o.maxidx
                idx = idx + 1;
            else
                idx = 1;
            end
            set(o.htimer,'UserData',idx);
            
            % Set camera position
            set(o.hax,'CameraPosition',[o.xdata(idx) o.ydata(idx) o.zdata]);
        end
        function pause(o)
        %PAUSE Pauses the spinning
        %
        %    PAUSE(o) pauses the spinning.
        %
        %            
            stop(o.htimer)
        end
        function stop(o)
        %STOP Stops the silliness
        %
        %    STOP(o) stops the spinning. Worst of all, it closes the
        %    surface plot, erasing all the trace of awesomeness that took
        %    place just not too long ago.
        %
        %    Sigh, oh well. Let's just get back to work.
        %
        %            
            stop(o.htimer)
            delete(o.htimer)
            close(get(o.hax,'Parent'))
        end

    end
    
end