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    <p>Note that the function <a href="https://www.mathworks.com/help/matlab/ref/trisurf.html" rel="nofollow noreferrer"><code>trisurf</code></a> that you were originally trying to use returns a handle to a <em>patch</em> object. If you look at the <a href="https://www.mathworks.com/help/matlab/ref/patch-properties.html#property_d0e724248" rel="nofollow noreferrer"><code>'FaceColor'</code> property for patch objects</a>, you can see that there is no <code>'texturemap'</code> option. That option is only valid for the <a href="https://www.mathworks.com/help/matlab/ref/primitivesurface-properties.html#property_d0e891374" rel="nofollow noreferrer"><code>'FaceColor'</code> property of <em>surface</em> objects</a>. You will therefore have to find a way to plot your triangular surface as a <em>surface</em> object instead of a <em>patch</em> object. Here are two ways to approach this:</p> <h2>If your data is in a uniform grid...</h2> <p>If the coordinates of your surface data represent a uniform grid such that <code>z</code> is a rectangular set of points that span from <code>xmin</code> to <code>xmax</code> in the x-axis and <code>ymin</code> to <code>ymax</code> in the y-axis, you can plot it using <a href="https://www.mathworks.com/help/matlab/ref/surf.html" rel="nofollow noreferrer"><code>surf</code></a> instead of <a href="https://www.mathworks.com/help/matlab/ref/trisurf.html" rel="nofollow noreferrer"><code>trisurf</code></a>:</p> <pre><code>Z = ... % N-by-M matrix of data x = linspace(xmin, xmax, size(Z, 2)); % x-coordinates for columns of Z y = linspace(ymin, ymax, size(Z, 1)); % y-coordinates for rows of Z [X, Y] = meshgrid(x, y); % Create meshes for x and y C = imread('image1.jpg'); % Load RGB image h = surf(X, Y, Z, flipdim(C, 1), ... % Plot surface (flips rows of C, if needed) 'FaceColor', 'texturemap', ... 'EdgeColor', 'none'); axis equal </code></pre> <p>In order to illustrate the results of the above code, I initialized the data as <code>Z = peaks;</code>, used the built-in sample image <code>'peppers.png'</code>, and set the <code>x</code> and <code>y</code> values to span from 1 to 16. This resulted in the following texture-mapped surface:</p> <p><a href="https://i.stack.imgur.com/gxZNt.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gxZNt.jpg" alt="enter image description here"></a></p> <h2>If your data is non-uniformly spaced...</h2> <p>If your data are not regularly spaced, you can create a set of regularly-spaced <code>X</code> and <code>Y</code> coordinates (as I did above using <a href="https://www.mathworks.com/help/matlab/ref/meshgrid.html" rel="nofollow noreferrer"><code>meshgrid</code></a>) and then use one of the functions <a href="https://www.mathworks.com/help/matlab/ref/griddata.html" rel="nofollow noreferrer"><code>griddata</code></a> or <a href="https://www.mathworks.com/help/matlab/ref/triscatteredinterp.html" rel="nofollow noreferrer"><code>TriScatteredInterp</code></a> to interpolate a regular grid of <code>Z</code> values from your irregular set of <code>z</code> values. I discuss how to use these two functions in <a href="https://stackoverflow.com/a/1674574/52738">my answer to another SO question</a>. Here's a refined version of the code you posted using <code>TriScatteredInterp</code> (Note: as of R2013a <a href="https://www.mathworks.com/help/matlab/ref/scatteredinterpolant-object.html" rel="nofollow noreferrer"><code>scatteredInterpolant</code></a> is the recommended alternative):</p> <pre><code>x = ... % Scattered x data y = ... % Scattered y data z = ... % Scattered z data xmin = min(x); xmax = max(x); ymin = min(y); ymax = max(y); F = TriScatteredInterp(x(:), y(:), z(:)); % Create interpolant N = 50; % Number of y values in uniform grid M = 50; % Number of x values in uniform grid xu = linspace(xmin, xmax, M); % Uniform x-coordinates yu = linspace(ymin, ymax, N); % Uniform y-coordinates [X, Y] = meshgrid(xu, yu); % Create meshes for xu and yu Z = F(X, Y); % Evaluate interpolant (N-by-M matrix) C = imread('image1.jpg'); % Load RGB image h = surf(X, Y, Z, flipdim(C, 1), ... % Plot surface 'FaceColor', 'texturemap', ... 'EdgeColor', 'none'); axis equal </code></pre> <p>In this case, you have to <em>first</em> choose the values of <code>N</code> and <code>M</code> for the size of your matrix <code>Z</code>. In order to illustrate the results of the above code, I initialized the data for <code>x</code>, <code>y</code>, and <code>z</code> as follows and used the built-in sample image <code>'peppers.png'</code>:</p> <pre><code>x = rand(1, 100)-0.5; % 100 random values in the range -0.5 to 0.5 y = rand(1, 100)-0.5; % 100 random values in the range -0.5 to 0.5 z = exp(-(x.^2+y.^2)./0.125); % Values from a 2-D Gaussian distribution </code></pre> <p>This resulted in the following texture-mapped surface:</p> <p><a href="https://i.stack.imgur.com/dnKlJ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dnKlJ.jpg" alt="enter image description here"></a></p> <p>Notice that there are jagged edges near the corners of the surface. These are places where there were too few points for <code>TriScatteredInterp</code> to adequately fit an interpolated surface. The <code>Z</code> values at these points are therefore <a href="https://www.mathworks.com/help/matlab/ref/nan.html" rel="nofollow noreferrer"><code>nan</code></a>, resulting in the surface point not being plotted.</p>
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    1. COI'm not particular to using trisurf, as long as I get some sort of mesh, may it be a patch, surface, mesh, or etc. object type. What additional information do you need to know about the patch object?
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    2. CO@srand: I updated my answer with some general guidelines for creating a surface of regularly-spaced points from your data, whatever it may be.
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    3. COI keep getting ??? Error using ==> flipud at 19 X must be a 2-D matrix.
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