GetSubTable

Map RGB from color table to nearest match on target table

#include <Quickdraw.h> Color Manager

void GetSubTable(myColors, iTabRes, targetTbl );

CTabHandle myColors ; handle to a source color table

short iTabRes ; controls the resolution of the inverse table

short targetTbl; table for which colors are being matched

GetSubTable maps colors between two or more color tables, returning the

nearest matches in myColor's colorSpec.value fields, and placing the returned

indices into targetTbl.

myColors is a handle to a ColorTable.

iTabRes specifies the resolution of a temporary inverse color table.

targetTbl is the target table for which each RGB value is being matched.

Notes: GetSubTable uses myColors to show the address of a ColorTable,

maps each RGB value to its closest equivalent for each target table,

and returns these approximations in myColor's colorSpec. value

fields. The colors are chosen using Color2Index. GetSubTable

builds and then discards a temporary inverse table (which requires

memory in the application heap equivalent to twice the size of the

table, plus a fixed overhead for each inverse table resolution of 3 to

15K bytes). ITabRes controls the temporary inverse table's

resolution. The only time your application doesn't build a temporary

table is if the targetTbl is NIL. In that case, the current gDevice's

color table is used--along with its inverse table. You can pass an

explicit targetTbl parameter (other than NIL) if you want to provide

a resolution different than the current inverse table.

Referenced by (1):