draw_gouraud_sprite - Draws a sprite with gouraud shading. Allegro game programming library.

       More  sophisticated version of draw_lit_sprite(): the `color' parameter is not constant across the sprite
       image anymore but interpolated between the four specified corner colors. The corner values passed to this
       function indicate the strength of the color applied on them, ranging from 0 (no strength)  to  255  (full
       strength). Example:

          /* Some one time initialisation code. */
          COLOR_MAP global_light_table;
          create_light_table(&global_trans_table, my_palette,
                             0, 0, 0, NULL);
          ...
          if (get_color_depth() == 8)
             color_map = &global_light_table;
          else
             set_trans_blender(0, 0, 0, 128);

          /* Enemies are in shadow unless lit by torch. */
          draw_gouraud_sprite(buffer, menacing_spy, x, y,
                              light_strength_on_corner_1,
                              light_strength_on_corner_2,
                              light_strength_on_corner_3,
                              light_strength_on_corner_4);

       draw_gouraud_sprite - Draws a sprite with gouraud shading. Allegro game programming library.

draw_sprite(3alleg4),     draw_lit_sprite(3alleg4),    color_map(3alleg4),    set_trans_blender(3alleg4),
       bitmap_mask_color(3alleg4), exshade(3alleg4)

Allegro                                           version 4.4.3                     draw_gouraud_sprite(3alleg4)

#include<allegro.h>voiddraw_gouraud_sprite(BITMAP*bmp,BITMAP*sprite,intx,inty,intc1,intc2,intc3,intc4);