extrans(3) - Linux man page
Name
extrans - Lighting and translucency effects. Allegro game programming library.
Synopsis
#include <allegro.h>
Example extrans
Description
This program demonstrates how to use the lighting and translucency functions. The first part of the
example will show a dark screen iluminated by a spotlight you can move with your mouse. After a keypress the example shows the full bitmap and the spotlight
changes to be a reduced version of the background with 50% of translucency.
The translucency effect is easy to do in all color depths. However, the lighting effect has to be performed in a different way depending on whether the
screen is in 8bit mode or another color depth. This is because additive drawing mode uses a different set of routines for truecolor modes.
See Also
bitmap(3), color_map(3), end_of_main(3), palette(3),
rgb(3), rgb_map(3), screen_h(3), screen_w(3), allegro_error(3),
allegro_init(3), allegro_message(3), bitmap_color_depth(3), blit(3), circlefill(3),
clear_bitmap(3), clear_keybuf(3), color_map(3), create_bitmap(3), create_bitmap_ex(3),
create_light_table(3), create_rgb_table(3), create_trans_table(3), destroy_bitmap(3),
draw_trans_sprite(3), drawing_mode(3), install_keyboard(3), install_mouse(3),
install_timer(3), keypressed(3), load_bitmap(3), mouse_x(3), mouse_y(3),
poll_mouse(3), rectfill(3), replace_filename(3), rest(3), rgb_map(3),
screen(3), set_alpha_blender(3), set_gfx_mode(3), set_palette(3), set_trans_blender(3),
set_write_alpha_blender(3), stretch_blit(3)