The
Source
0 <= x < Width,
0 <= y < Height
|
The X
Map
0 <= X(x , y)
<= 255
|
The Y
Map
0 <= Y(x , y)
<= 255
|
|
The three textures
can come from anywhere and the X , Y Maps
do not have to be the same
picture.
We split the main
colours (Red Green Blue) and treat each
independantly.
As we see, there are
two kinds of mapping, Direct and Offset.
Each produces
radically different results from the same
sources.
The Source
coordinates are modulated to point inside
the picture.
|
|
The
Direct Map
D(x , y) = S(X(x , y)
, Y(x , y))
|
If the Source is
larger than 256x256, only the square of
that size contributes to
D(x,y).
|
|
The
Offset Map
A(x , y) = S(x + X(x
, y) , y + Y(x , y))
|
If the Source is
larger than 512x512 only the square of
that size will contribute to
A(x,y).
|
|
