Rasterizing Delaunay triangulation in Matlab

Question

I have computed a Delaunay triangulation using DelaunayTri() in Matlab R2010b . Now I would like to burn a subset of the triangles (ie 12200 triangles) into a matrix (Raster). Is there any fast/efficient way of doing this?

I have tried using both poly2mask() and inpolygon() to select pixels inside the triangles, but this is rather slow.

Answer 1

I implemented this fast solution:

qrypts=[xgridcoords, ygridccords]; %grid x and y coordinates
triids = pointLocation(dt, qrypts); %associate each grid point to its Delaunay triangle
Lia = ismember(triids,dtsubset); %keep subset of points contained in the desired triangles (dtsubset contains the indices of desired triangles)
IM=false(size(grid)); 
IM(Lia)=1;