How to preserve the 3d plot box, when changing patch visibility.

I have a 3d plot with a collection of patches. If I set a subset of patches Visible attributes to 'off', the plot box is recomputed. How can I capture and preserve all aspects of the plot box so that the visible patches don't jump around as other patches become visible or invisible.

Answer 1

[Matt J]

Here's something a little fancier, and maybe more robust. It captures (and reasserts) all relevant properties of the plot perspective, including camera angles and such:

figure;
ax = gca;
% drop some data between 1 and 5 in all 3 dimensions
for x = 1:4:5
    for y = 1:4:5
        line([x,x],[y,y],[1,5]);
    end
end
axis equal;
view(ax,[1,1,1]);

fpose=figPose(ax);
figPose(ax, fpose)

ax.XLimMode %Verify manual mode

ans = 'manual'

ax.YLimMode

ans = 'manual'

ax.ZLimMode

ans = 'manual'

function varargout = figPose(varargin)
%figPose Record or assert a 3-D camera/figure pose
%
%Record pose
%
%   S = figPose();
%   S = figPose(ax);
%
%Apply pose
%
%   figPose(S)
%   figPose(ax,S)
%
%The pose includes:
%   • Camera geometry
%   • Projection mode
%   • Axis limits / aspect ratios
%   • Figure size

    %--------------------------------------------
    % Resolve axis handle
    %--------------------------------------------
    
    if nargin == 0
        hAx = gca;
        varargin = {};
    else
        if isgraphics(varargin{1},'axes')
            hAx = varargin{1};
            varargin = varargin(2:end);
        else
            hAx = gca;
        end
    end
    
    assert(isvalid(hAx),'Axis invalid')
    
    hFig = ancestor(hAx,'figure');
    
    assertPose = ~isempty(varargin) && isstruct(varargin{1});
    
    %--------------------------------------------
    % Properties to clone
    %--------------------------------------------
    
    camProps = { ...
        'CameraPosition',...
        'CameraTarget',...
        'CameraUpVector',...
        'CameraViewAngle',...
        'Projection'};
    
    axisProps = { ...
        'XLim','YLim','ZLim',...
        'DataAspectRatio',...
        'PlotBoxAspectRatio'};
    
    %--------------------------------------------
    % Apply pose
    %--------------------------------------------
    
    if assertPose
    
        S = varargin{1};
    
        % Lock camera modes
        set(hAx,...
            'CameraPositionMode','manual',...
            'CameraTargetMode','manual',...
            'CameraUpVectorMode','manual',...
            'CameraViewAngleMode','manual');
    
        % Restore camera
        set(hAx,camProps,S.cam);
    
        % Restore axis geometry if present
        if isfield(S,'axis')
            set(hAx,axisProps,S.axis);
        end
    
        % Restore figure size
        if isfield(S,'figpos')
            set(hFig,'Position',S.figpos);
        end
    
    %--------------------------------------------
    % Capture pose
    %--------------------------------------------
    
    else
    
        S.cam  = get(hAx,camProps);
        S.axis = get(hAx,axisProps);
        S.figpos = hFig.Position;
    
        varargout = {S};
    
    end
end

Answer 2

[Matt J]

Using axis() twice, we can both capture and reassert the axis limits,

axis(axis)

This also then converts all X,Y,ZLimModes to 'manual' so automatic changes will not happen.

[Matt J]

Borrowing your example,

figure;
ax = gca;
% drop some data between 1 and 5 in all 3 dimensions
for x = 1:4:5
    for y = 1:4:5
        line([x,x],[y,y],[1,5]);
    end
end
axis equal;
view(ax,[1,1,1]);

originalLimits = axis %Check the current axis limits

originalLimits = 1×6

0.4628 5.5372 1.0000 5.0000 0.5000 5.5000

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axis(axis) %assert the limits and change to manual limit mode

isequal(originalLimits,axis) %recheck axis limits -- they're unchanged

ans = logical
   1

ax.XLimMode %Verify manual mode

ans = 'manual'

ax.YLimMode

ans = 'manual'

ax.ZLimMode

ans = 'manual'

[John]

Yes, that's working for me.

(But on code hygeine grounds, I hate it. What does axis(axis) do? In other languages, it might look like a copy constructor. Or maybe the Y combinator, invoking a function on itself. In matlab, it's some magic incantation whose semantics are completely independent of the rest of the language. Bleh.)

[Voss]

"What does axis(axis) do?"

It's the same as

lim = axis();
axis(lim)

but without assigning to the variable lim.

Both of those usages are documented.

[Matt J]

In matlab, it's some magic incantation whose semantics are completely independent of the rest of the language.

There must be dozens of other graphics commands that behave the same way:

xlim(xlim)  %reasserts x-limits
ylim(ylim)  %reasserts y-limits
zlim(zlim)  %reasserts z-limits
campos(campos)
camva(camva)
camup(camup)
view(view)
figure(figure(n))

Answer 3

[Voss]

You don't need to capture anything.

To preserve the axes limits as they are, set the axes XLimMode, YLimMode, and ZLimMode to 'manual'. Obviously you would do that at a point in the code where the axes limits are what you want them to be, e.g., after all patches are initialized.

Other axes properties besides the limits affect the plot box, so you may want to set some other properties' modes to 'manual' as well in order to disable all undesired automatic changes to the plot box, e.g., PlotBoxAspectRatioMode, CameraViewAngleMode, etc. Look through the axes properties to see what you have control over:

https://www.mathworks.com/help/matlab/ref/matlab.graphics.axis.axes-properties.html

[John]

It seems I do need to capture previous values because setting the ?LimMode's causes the limits to change.

See below how the ZLim values change when the YLimMode is set.

>> [ax.XLim, ax.YLim, ax.ZLim]

ans =

-0.1561    6.1561    1.0000    5.0000    0.5000    5.5000
>> ax.XLimMode = 'manual';
>> ax.YLimMode = 'manual';
>> [ax.XLim, ax.YLim, ax.ZLim]

ans =

-0.1561    6.1561    1.0000    5.0000    1.0000    5.0000

[Voss]

Interesting

[Stephen23]

Report it as a bug with R2025x: https://www.mathworks.com/support/contact_us.html

[John]

It's definitely an Xbug (i.e. unexpected behavior). Whether it's a bug depends on whether all the auto-scaling behavior has a comprehensive description somewhere in the documentation. This code demonstrates the (X)bug.

figure;
ax = gca;
% drop some data between 1 and 5 in all 3 dimensions
for x = 1:4:5
    for y = 1:4:5
        line([x,x],[y,y],[1,5]);
    end
end
axis equal;
view(ax,[1,1,1]);

[ax.XLim, ax.YLim, ax.ZLim]

ans = 1×6

0.4628 5.5372 1.0000 5.0000 0.5000 5.5000

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<mw-icon class=""></mw-icon>

ax.XLimMode = 'manual';
ax.YLimMode = 'manual';
[ax.XLim, ax.YLim, ax.ZLim]

ans = 1×6

0.4628 5.5372 1.0000 5.0000 1.0000 5.0000

<mw-icon class=""></mw-icon>

<mw-icon class=""></mw-icon>

ax.ZLimMode = 'manual';

[Voss]

If you set the modes all at once, i.e.,

set(ax,'XLimMode','manual','YLimMode','manual','ZLimMode','manual')

Then the limits don't change.

Answer 4

[Nick]

you may change patch color to fully transparent instead, e.g.

patch_handle.FaceAlpha = 0;
% or make use of the function
alpha(patch_handle, 'clear');
% prepend with "hold on;" if necessary

[John]

That's an interesting suggestion. One difference (between setting alpha and setting object visibility) might be in the behavior of tooltips. I haven't done much with tooltips yet, but plan to.