Need assistance with beginner collision code

Flinch (5)
I have taken quite a few hours to investigate this myself. I am very new to C++ and have only found trouble when trying to fix this. Perhaps someone can help.

I use allegro with Dev-C++.

This code was a tutorial from the internet, part 8 of 9.
http://www.loomsoft.net/resources/alltut/alltut_lesson8.htm

After spending those hours looking for a solution I finally gave in and simply copy/pasted the code from the site. It gave me the same error.

My errors are the following:
a function-definition is not allowed here before '{' token
expected `,' or `;' before '{' token
expected `}' at end of input

And here is the code:
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#include <allegro.h>
#include <stdlib.h>

volatile long speed_counter = 0; //integer to store value of the speed counter
void increment_speed_counter() //function to increment the speed counter
{
     speed_counter++;
     }
END_OF_FUNCTION(increment_speed_counter);

int main(int argc, char *argv[])
{
    allegro_init();
    install_keyboard();
    install_timer();
    
    LOCK_VARIABLE(speed_counter);
    LOCK_FUNCTION(increment_speed_counter);
    install_int_ex(increment_speed_counter, BPS_TO_TIMER(60));
    
    set_color_depth(16);
    set_gfx_mode(GFX_AUTODETECT, 640,480,0,0);
    
    BITMAP *buffer = create_bitmap(640,480); //create a buffer for smooth animation
    if(buffer == NULL)
    {
              set_gfx_mode(GFX_TEXT,0,0,0,0);
              allegro_message("Could not create buffer!");
              exit(EXIT_FAILURE);
              }
BITMAP *image1 = load_bitmap("C:/Dev-Cpp/Teh Stuph/AL8/image1.bmp", NULL);
if(image1 == NULL)
{
          set_gfx_mode(GFX_TEXT,0,0,0,0); //sets screen mode for allegro messages
          allegro_message("Could not load image1.bmp");
          exit(EXIT_FAILURE);
          }
BITMAP *image2 = load_bitmap ("C:/Dev-Cpp/Teh Stuph/AL8/image2.bmp", NULL);
if(image2 == NULL)
{
          set_gfx_mode(GFX_TEXT,0,0,0,0);
          allegro_message("Could not load image2.bmp");
          exit(EXIT_FAILURE);
          }
int image1_x_position = 0;
int image1_y_position = 0;

int image2_x_position = 100;
int image2_y_position = 100;

int image1_bb_left = image1_x_position;
int image1_bb_top = image1_y_position;
int image1_bb_right = (image1_bb_left + image1->w);
int image1_bb_bottom = (image1_bb_top + image1->h);

int image2_bb_left = image2_x_position;
int image2_bb_top = image2_y_position;
int image2_bb_right = (image2_bb_left + image2->w);
int image2_bb_bottom = (image2_bb_top + image2->h);

int show_bbox = FALSE;
int collision = FALSE;

while(!key[KEY_ESC])
{
                    while(speed_counter > 0)
                    {
                    if(key[KEY_LEFT])
                    image1_x_position --;
                    if(key[KEY_RIGHT])
                    image1_x_position ++;
                    if(key[KEY_DOWN])
                    image1_y_position ++;
                    if(key[KEY_UP])
                    image1_y_position --;
                    
                    if(key[KEY_A])
                    image2_x_position --;
                    if(key[KEY_D])
                    image2_x_position ++;
                    if(key[KEY_S])
                    image2_y_position --;
                    if(key[KEY_W])
                    image2_y_position ++;
                    
                    if(key[KEY_SPACE])
                    show_bbox = TRUE;
                    else if(!key[KEY_SPACE])
                    show_bbox = FALSE;
                    
                    image1_bb_left = image1_x_position;
                    image1_bb_top = image1_y_position;
                    image1_bb_right = (image1_bb_left + image1->w);
                    image1_bb_bottom = (image1_bb_top + image1->h);
                    
                    image2_bb_left = image1_x_position;
                    image2_bb_top = image1_y_position;
                    image2_bb_right = (image2_bb_left + image2->w);
                    image2_bb_bottom = (image2_bb_top + image2->h);
                    
                    collision = TRUE; //assume there is a collision
                    if(image1_bb_bottom < image2_bb_top)
                    {
                                        collision = FALSE;
                                        }
                    if(image1_bb_top > image2_bb_bottom)
                    {
                                     collision = FALSE;
                                     }
                    if(image1_bb_right < image2_bb_left)
                    {
                                       collision = FALSE;
                                       }
                    if(image1_bb_left < image2_bb_right)
                    {
                                      collision = FALSE;
                                      }
                    speed_counter --;
                    }

draw_sprite(buffer, image1, image1_x_position, image1_y_position);
draw_sprite(buffer, image2, image2_x_position, image2_y_position);

if(show_bbox == TRUE)
{
line(buffer, image1_bb_left, image1_bb_top, image1_bb_right, image1_bb_top, makecol(255,0,0));
line(buffer, image1_bb_left, image1_bb_bottom, image1_bb_right, image1_bb_bottom, makecol(255,0,0));
line(buffer, image1_bb_left, image1_bb_top, image1_bb_left, image1_bb_bottom, makecol(255,0,0));
line(buffer, image1_bb_right, image1_bb_top, image1_bb_right, image1_bb_bottom, makecol(255,0,0));

line(buffer, image2_bb_left, image2_bb_top, image2_bb_right, image2_bb_top, makecol(255,0,0));
line(buffer, image2_bb_left, image2_bb_bottom, image2_bb_right, image2_bb_bottom, makecol(255,0,0));
line(buffer, image2_bb_left, image2_bb_top, image2_bb_left, image2_bb_bottom, makecol(255,0,0));
line(buffer, image2_bb_right, image2_bb_top, image2_bb_right, image2_bb_bottom, makecol(255,0,0));
}

if(collision == TRUE)
{
             textprintf_ex(buffer, font, 0,0, makecol(255,255,255), -1, "Collision!");
             }

blit(buffer, screen, 0,0,0,0,640,480); //blit the buffer
clear(buffer); //clear the buffer

destroy_bitmap(buffer);
destroy_bitmap(image1);
destroy_bitmap(image2);

return 0;
}
END_OF_MAIN()
Last edited on
Timaster (52)
I'd recommend that you start C++ without Allegro, first... but I don't know anything about Allegro, so I can't help you with this specifically.
Flinch (5)
I have done quite a few things without allegro, my interests just push me into it. It's so tempting to try this idea. Two objects that can collide, I know it's simple but I couldn't resist. I will take your advice and work on C++ mainly at first.
firedraco (6243)
I believe the loop on line 64 while(!key[KEY_ESC]) is missing an ending brace somewhere...I can't tell for sure because the indentation got kind of weird at the end.
Flinch (5)
I've been working on the possible solution of a missing brace, no luck yet. Thank for your input though Firedraco, hopefully I'll get it soon.
Zaita (2770)
I have some Collission Detection code at home that doesn't use Allegro. Would you like me to post it after work?
omegazero (8)
Might it have to do with END_OF_MAIN() [assuming that is a function in allegro] being called after the main executes? or that increment_speed_counter() never appears to be called? maybe I'm just blind.
Mal Reynolds (111)
firedraco is right, put it in notepad++, use folding, the while loop has no closing brace. he is again also correct that it is unclear where that loop is supposed to end, otherwise i could pinpoint it for you.
Flinch (5)
Zaita, I would appreciate that! Please do.

Mal, I'm going to try the idea with notepad++. I actually wasn't aware of that until you said something, so thank you.

Omega, I was thinking along the same lines and have been trying each idea I can think of. I'm probably overlooking something simple.

Thank you all for aiding me in finding a solution.
Last edited on
Zaita (2770)
No worries. Have left myself a message to post it tonight when I get home.

Z.
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