Rectangular Image

Rectangular grid, sometimes referred to a logically rectangular is often used for body fitted grids. It is more flexible than uniform grid where the step size in x and y are uniform. For logically rectangular the values are in a rectangular array and indexed by (i,j) just like uniform grids, but the coordinate of (i,j) is given by (x(i,j),y(i,j)) instead of (origin.x + i*dx, origin.y+j*dy) like it is for uniform.

The following screen shot shows how a uniform grid is converted to a logically rectangular grid and then mapped using a conformal mapping.