[mapserver-users] Using CLASS and SCALE at the same time

[Axel Bayerl]

Hello,

i was wondering if it is possible to use PROCESSING "SCALE=min,max",
and the output of that feed it to CLASS to classify the data.

Example:

I have a image which min and max is 0 and 5.4 respectively.

I want to SCALE it to get it in the 0-255 range.
PROCESSING "SCALE=0,5.4"

Then i want to apply a LUT, and classify the values (all with the 0-255 range)
PROCESSING "LUT=u.curve"

CLASS
    NAME "0"
    EXPRESSION ([pixel] = 0)
    STYLE
        COLOR 0   0   0
    END
END
CLASS
    NAME "1"
    EXPRESSION ([pixel] >= 1 AND [pixel] < 3)
    STYLE
        COLOR 255   0   0
    END
END
CLASS
    NAME "2"
    EXPRESSION ([pixel] >= 3 AND [pixel] < 7)
    STYLE
        COLOR 255  23   0
    END
END
CLASS
    NAME "3"
    EXPRESSION ([pixel] >= 7 AND [pixel] < 11)
    STYLE
        COLOR 255  47   0
    END
END
CLASS
    NAME "4"
    EXPRESSION ([pixel] >= 11 AND [pixel] < 15)
    STYLE
        COLOR 255  71   0
    END
END
....

But when i classify the processing scale is ignored (and LUT).

In short, i want for the expression of class to manage the scaled (and
LUTed) value of the pixel, not the pixel value itself.

Thanks.
Axel.

PS: the raster is of type Float32.