create_trans_table

create_trans_table(3alleg4)     Allegro manual     create_trans_table(3alleg4)



NAME
       create_trans_table - Fills a color mapping table for translucency
       effects. Allegro game programming library.

SYNOPSIS
       #include <allegro.h>


       void create_trans_table(COLOR_MAP *table, const PALETTE pal, int r, g,
       b, void (*callback)(int pos));

DESCRIPTION
       Fills the specified color mapping table with lookup data for doing
       translucency effects with the specified palette. When combining the
       colors c1 and c2 with this table, the result will be a color somewhere
       between the two. The r, g, and b parameters specify the solidity of
       each color component, ranging from 0 (totally transparent) to 255
       (totally solid). For 50% solidity, pass 128.

       This function treats source color #0 as a special case, leaving the
       destination unchanged whenever a zero source pixel is encountered, so
       that masked sprites will draw correctly. This function will take
       advantage of the global rgb_map variable to speed up color conversions.
       If the callback function is not NULL, it will be called 256 times
       during the calculation, allowing you to display a progress indicator.
       Example:

          COLOR_MAP trans_table;
          ...
          /* Build a color lookup table for translucent drawing. */
          create_trans_table(&trans_table, pal, 128, 128, 128, NULL);


SEE ALSO
       color_map(3alleg4), create_light_table(3alleg4),
       create_color_table(3alleg4), create_blender_table(3alleg4),
       draw_trans_sprite(3alleg4), draw_lit_sprite(3alleg4),
       draw_gouraud_sprite(3alleg4), rgb_map(3alleg4), ex3d(3alleg4),
       extrans(3alleg4)



Allegro                          version 4.4.2     create_trans_table(3alleg4)