add comments

src/image.jl

@@ -278,11 +278,15 @@ function project_qi_lagrange!(u::FeFunction, img)
             # size: nrdims
             value = evaluate(f, xhat)
             # size: nldofs
+            # actually: transformation to barycentric coordinates!
             phix = evaluate_basis(space.element, xhat)
 
             # no integration element used
             #u.data[gdofs] .+= qw[k] ./ area_refel .* 3 .* value * phix'
             u.data[gdofs] .+= qw[k] ./ area_refel * value * (12 .* phix' .- 3)
+
+            #rhox = SA[-12 -12; 12 0; 0 12] * xhat + SA[9, -3, -3]
+            #u.data[gdofs] .+= qw[k] ./ area_refel * value * rhox'
         end
         gdofcount[gdofs] .+= 1
     end