From the MathWorks Support Team from How to set the transparency of LINE objects in MATLAB 7.14 (R2012a)? ( mirror ):
Line series objects do not support transparency values (alpha). To overcome this limitation, you can use the following workaround:
Example 1:n = 10; xs = rand(n,1); ys = rand(n,1); zs = rand(n,1)*3; plot3(xs,ys,zs,'r.') xlabel('x');ylabel('y');zlabel('z'); p = patchline(xs,ys,zs,'linestyle','--','edgecolor','g','linewidth',3,'edgealpha',0.2);
EXAMPLE 2:
t = 0:pi/64:4*pi; p(1) = patchline(t,sin(t),'edgecolor','b','linewidth',2,'edgealpha',0.5); p(2) = patchline(t,cos(t),'edgecolor','r','linewidth',2,'edgealpha',0.5); l = legend('sine(t)','cosine(t)'); tmp = sort(findobj(l,'type','patch')); for ii = 1:numel(tmp) set(tmp(ii),'facecolor',get(p(ii),'edgecolor'),'facealpha',get(p(ii),'edgealpha'),'edgecolor','none') end
patchline.m (by Brett Shoelson, June 20, 2012 (Updated September 1, 2016)):
function p = patchline(xs,ys,varargin) % Plot lines as patches (efficiently) % % SYNTAX: % patchline(xs,ys) % patchline(xs,ys,zs,...) % patchline(xs,ys,zs,'PropertyName',propertyvalue,...) % p = patchline(...) % % PROPERTIES: % Accepts all parameter-values accepted by PATCH. % % DESCRIPTION: % p = patchline(xs,ys,zs,'PropertyName',propertyvalue,...) % Takes a vector of x-values (xs) and a same-sized % vector of y-values (ys). z-values (zs) are % supported, but optional; if specified, zs must % occupy the third input position. Takes all PV % pairs supported by PATCH. Returns in p the handle % to the resulting patch object. % % NOTES: % Note that we are drawing 0-thickness patches here, % represented only by their edges. FACE PROPERTIES WILL % NOT NOTICEABLY AFFECT THESE OBJECTS! (Modify the % properties of the edges instead.) % % LINUX (UNIX) USERS: One test-user found that this code % worked well on his Windows machine, but crashed his % Linux box. We traced the problem to an openGL issue; % the problem can be fixed by calling 'opengl software' % in your <http://www.mathworks.com/help/techdoc/ref/startup.html startup.m>. % (That command is valid at startup, but not at runtime, % on a unix machine.) % % EXAMPLES: %%% Example 1: % % n = 10; % xs = rand(n,1); % ys = rand(n,1); % zs = rand(n,1)*3; % plot3(xs,ys,zs,'r.') % xlabel('x');ylabel('y');zlabel('z'); % p = patchline(xs,ys,zs,'linestyle','--','edgecolor','g',... % 'linewidth',3,'edgealpha',0.2); % %%% Example 2: (Note "hold on" not necessary here!) % % t = 0:pi/64:4*pi; % p(1) = patchline(t,sin(t),'edgecolor','b','linewidth',2,'edgealpha',0.5); % p(2) = patchline(t,cos(t),'edgecolor','r','linewidth',2,'edgealpha',0.5); % l = legend('sine(t)','cosine(t)'); % tmp = sort(findobj(l,'type','patch')); % for ii = 1:numel(tmp) % set(tmp(ii),'facecolor',get(p(ii),'edgecolor'),'facealpha',get(p(ii),'edgealpha'),'edgecolor','none') % end % %%% Example 3 (requires Image Processing Toolbox): %%% (NOTE that this is NOT the same as showing a transparent image on %%% of the existing image. (That functionality is %%% available using showMaskAsOverlay or imoverlay). %%% Instead, patchline plots transparent lines over %%% the image.) % % img = imread('rice.png'); % imshow(img) % img = imtophat(img,strel('disk',15)); % grains = im2bw(img,graythresh(img)); % grains = bwareaopen(grains,10); % edges = edge(grains,'canny'); % boundaries = bwboundaries(edges,'noholes'); % cmap = jet(numel(boundaries)); % ind = randperm(numel(boundaries)); % for ii = 1:numel(boundaries) % patchline(boundaries{ii}(:,2),boundaries{ii}(:,1),... % 'edgealpha',0.2,'edgecolor',cmap(ind(ii),:),'linewidth',3); % end % % Written by Brett Shoelson, PhD % brett.shoelson@mathworks.com % 5/31/2012 % % Revisions: % 6/26 Improved rice.png example, modified FEX image. % % Copyright 2012 MathWorks, Inc. % % See also: patch, line, plot [zs,PVs] = parseInputs(varargin{:}); if rem(numel(PVs),2) ~= 0 % Odd number of inputs! error('patchline: Parameter-Values must be entered in valid pairs') end % Facecolor = 'k' is (essentially) ignored here, but syntactically necessary if isempty(zs) p = patch([xs(:);NaN],[ys(:);NaN],'k'); else p = patch([xs(:);NaN],[ys(:);NaN],[zs(:);NaN],'k'); end % Apply PV pairs for ii = 1:2:numel(PVs) set(p,PVs{ii},PVs{ii+1}) end if nargout == 0 clear p end function [zs,PVs] = parseInputs(varargin) if isnumeric(varargin{1}) zs = varargin{1}; PVs = varargin(2:end); else PVs = varargin; zs = []; end
License:
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