Overlap two pcolor with different color and set up transparency

I have two figures like below.

What I want to do is 1) overlap them into one figure. 2) set transparency at the place where they meet each other. The colour can be changed, can be any color where an overlap will look nice.

Many thanks

[Shaibal Ahmed]

I have a similar question, would be great if someone could answer it.

Answer 1

[Chad Greene]

What about this?

% Some sample data: 
[X,Y,Z1] = peaks; 
Z2 = flipud(Z1); 

% Blue layer: 
p1 = surf(X,Y,zeros(size(Z1)),'AlphaData',Z1,...
    'FaceAlpha','interp',...
    'FaceColor','blue',...
    'edgecolor','none');

% Red layer:  
hold on
p2 = surf(X,Y,zeros(size(Z2)),'AlphaData',Z2,...
    'FaceAlpha','interp',...
    'FaceColor','red',...
    'edgecolor','none');

view(2) 
grid off

[Xin]

Thanks for your reply! Another issue is that the two figure has different colormap, how would you deal with it? Is it possible to put two different colormap together in one figure?

[Alexander Audet]

Yes, just figured this out. You need to put them on separate axes, then turn off the second axis visibility:

% Some sample data: 
[X,Y,Z1] = peaks; 
Z2 = flipud(Z1); 

figure

%Create the first axis and colormap
ax1 = axes;
hold on
colormap(ax1, hot)

% Plot on first axis
h1 = surf(ax1,X,Y,zeros(size(Z1)),Z1,'edgecolor','none')

%Create the second axis and colormap
ax2 = axes;
hold on
colormap(ax2, winter)

% Plot on second axis
h2 = surf(ax2,X,Y,zeros(size(Z2)),Z2,'edgecolor','none', 'FaceAlpha', 0.5)

% Turn 3D surface into 2D surface (map view)
view(2) 
grid off

%Turn off ax2 so you can see the first plot
ax2.Visible = 'off';
ax2.XTick = [];
ax2.YTick = [];

[Walter Roberson]

Historically there could only be one colormap for each figure, but that was changed eventually to permit one colormap per axes.