You should be able to use the surf function. The only problem you have is interpolating the data to a normal grid that surf understands (and fill the rest with NaN).
The code below assumes your text file is stored in a 2112 by 3 array named data
x=data(:,1);
y=data(:,2);
z=data(:,3);
SamplePerDim=500;
X=linspace(min(x),max(x),SamplePerDim);
Y=linspace(min(y),max(y),SamplePerDim);
[X,Y]=ndgrid(X,Y);
F=scatteredInterpolant(x,y,z,'linear','none');
Z=F(X,Y);
figure(1),clf(1)
surf(X,Y,Z,'EdgeColor','none')
view(-160,80)
