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 col-
ors 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. Exam-
ple:
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)
