Allegro Programming Tutorial, by Richard G Baldwin

The draw function

When the draw function is called in Listing 2:

The coordinate and color values stored in the local variables in Listing 1
Are passed as parameters.

A pointer to the off-screen buffer is also passed to the draw function.

The draw function is shown in its entirety in Listing 5.

Listing 5. The draw function.

void draw(int xCoor,int yCoor,BITMAP* buf,int color){ show_mouse(NULL);//hide mouse pointer while drawing //Draw filled circle at mouse coor on off-screen buffer. circlefill(buf,xCoor,yCoor,5,color); //Copy the off-screen image to the screen. blit(buf,screen,0,0,0,0,440,500); show_mouse(screen);//show mouse when drawing finished }//end draw