MATLAB: Transparency causes nonsmooth lines

smooth

When I set transparency in the figure, the original smooth line becomes nonsmooth.

[x,y] = meshgrid(-2:.2:2);

z = x.*exp(-x.^2-y.^2);

a = gradient(z);

figure; surf(x,y,z,'AlphaData',a,'FaceAlpha','flat','FaceColor','blue');

figure; surf(x,y,z)

Best Answer

Transparency requires the OpenGL renderer. The line-smoothing requires the Painters renderer. As far as I can see, you observe the expected behavior.

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MATLAB: How to export the whole figure data into MATLAB workspace

You can call the undocumented function hardcopy. But there are some pitfalls, e.g. the EraseMode of all objects must be 'normal', otherwise hardcopy crashs.

% Simulate PRINT command (save time for writing and reading image file):
% Set units of axes and text from PIXELS to POINTS to keep their sizes
% independent from from the output resolution:
% See: graphics/private/preparehg.m
root_SHH     = get(0, 'ShowHiddenHandles');
set(0, 'ShowHiddenHandles', 'on');
text_axes_H  = [findobj(FigH, 'Type', 'axes'); ...
       findobj(FigH, 'Type', 'text')];
pixelObj     = findobj(text_axes_H, 'Units',     'pixels');
fontPixelObj = findobj(text_axes_H, 'FontUnits', 'pixels');
set(pixelObj,     'Units',     'points');
set(fontPixelObj, 'FontUnits', 'points');
% Set image driver:
if strcmpi(fig_Renderer, 'painters')
   imageDriver = '-dzbuffer';
else
   imageDriver = ['-d', fig_Renderer];
end
fig_ResizeFcn = get(FigH, 'ResizeFcn');
set(FigH, 'ResizeFcn', '');
% "Normal" is the only erasemode, which can be rendered!
% See: NOANIMATE.
EraseModeH = [ ...
    findobj(FigH, 'EraseMode', 'xor'); ...
    findobj(FigH, 'EraseMode', 'none'); ...
    findobj(FigH, 'EraseMode', 'background')];
EraseMode = get(EraseModeH, {'EraseMode'});
set(EraseModeH, 'EraseMode', 'normal');
% Get image as RGB array:
high = hardcopy(FigH, imageDriver, '-r300');
% Restore units of axes and text objects, and EraseMode:
set(pixelObj,     'Units',     'pixels');
set(fontPixelObj, 'FontUnits', 'pixels');
set(EraseModeH, {'EraseMode'}, EraseMode);
set(0, 'ShowHiddenHandles', root_SHH);
set(FigH, 'ResizeFcn', fig_ResizeFcn);

MATLAB: Are UIPANELs renderered incorrectly, when using the OpenGL renderer

This bug has been fixed for Release 14 SP1 (R14SP1). For previous releases, please read below for any possible workarounds:

This is a bug in MATLAB 7.0 (R14), related to the calculation of the location of the background area in uipanels.

As a work around, use the zbuffer or painters renderers:

set(gcf,'Renderer','zbuffer')
set(gcf,'Renderer','painters')

Best Answer

Related Solutions

MATLAB: How to export the whole figure data into MATLAB workspace

MATLAB: Are UIPANELs renderered incorrectly, when using the OpenGL renderer

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