%PLOTBEZIER   Plot Bezier Curve
% Plot Bezure curve, Bezure points and velocity.
%
% Syntax:  plotbezier(dt, CP)
%
% Inputs:
%    dt - the parameter increment size that you want points along the 
%         curve to be plotted at.  Remember the parameter varies from 
%         0 - 1 along the curve, dt = .01 will give 100 points
%    CP - a nxm vector of n control points in 1, 2 or 3-space 
%
% Outputs:
%    - a plot of the characteristic polygon
%    - a plot of the curve as a series of equi-spaced points in terms of
%      the curve parameter t.
%    - a separate plot of velocity variation as a function of the parameter t
%
% Other m-files required: bezier.m
%
% See also: BEZIER

% Author: Travis Hydzik
% Last revision: 20 October 2004

function plotbezier(dt, CP)
    v = [];
    p = CP(1,:);
    x = p;
	
    for t = dt:dt:1
        pNew = bezier(t, CP);
        v = [v norm(pNew - p)];
        p = pNew;
        x = [x; p];
	end
    
	[n, m] = size(x);
    
    clf
    subplot(1,2,1)
    if m == 1
        line(CP(:,1), zeros(1,m), 'Marker', '+', 'MarkerEdgeColor','b' );
        hold on
	    line(x(:,1), zeros(1,m), 'LineStyle','none', 'Marker', '.', 'MarkerEdgeColor','r' );
    elseif m == 2
        line(CP(:,1),CP(:,2), 'Marker', '+', 'MarkerEdgeColor','b' );
        hold on
	    line(x(:,1),x(:,2),'LineStyle','none', 'Marker', '.', 'MarkerEdgeColor','r' );
    elseif m == 3
        line(CP(:,1),CP(:,2),CP(:,3), 'Marker', '+', 'MarkerEdgeColor','b' );
        hold on
        line(x(:,1),x(:,2),x(:,3),'LineStyle','none', 'Marker', '.', 'MarkerEdgeColor','r' );
        cosmetics(3)
    end
    hold off

    subplot(1,2,2)
    plot(v)