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#define PLAYER_IS_OK 1
#define PLAYER_IS_DEAD 2
#define PLAYER_HAS_WON 3
// player_action moves the player
// It returns one of the three PLAYER_ define values ( top of this file )
int player_action( signed int xdiff, signed int ydiff, struct level_struct *currentlevel )
{
// Find the tile the player moved into/onto using the player's current position
int newx = currentlevel->px + xdiff;
int newy = currentlevel->py + ydiff;
// Cycle through the player's faces
currentlevel->player_face++;
if ( currentlevel->player_face == 4 ) currentlevel->player_face = 0;
// Check to make sure these directions are not solid ( ie walls )
// and also to see if they are interactive ( ie buttons )
char targetsquare = currentlevel->squares[newx][newy];
if ( targetsquare == T_WALL || targetsquare == T_YELL_DOOR_UP || targetsquare == T_BLUE_DOOR_UP || targetsquare == T_RED_DOOR_UP ) // remember '||' means 'OR'
{
// Cannot move, so do nothing
return PLAYER_IS_OK;
}
else
{
// Move onto the new square
currentlevel->px = newx;
currentlevel->py = newy;
// Check to see if the new square is interactive ( ie a button )
switch ( targetsquare )
{
case T_BLUE_BUTT_UP: // Blue button
// Change the button to be depressed
currentlevel->squares[newx][newy] = T_BLUE_BUTT_DOWN;
// Change all blue doors in the level to be unlocked
level_replace_tiles( currentlevel, T_BLUE_DOOR_UP, T_BLUE_DOOR_DOWN );
return PLAYER_IS_OK;
case T_YELL_BUTT_UP: // Yellow button
// Change the button to be depressed
currentlevel->squares[newx][newy] = T_YELL_BUTT_DOWN;
// Change all blue doors in the level to be unlocked
level_replace_tiles( currentlevel, T_YELL_DOOR_UP, T_YELL_DOOR_DOWN );
return PLAYER_IS_OK;
case T_EXIT:
// User is on the exit
return PLAYER_HAS_WON;
case T_SPIKE:
// The daft player walked onto spikes
return PLAYER_IS_DEAD;
default:
// This has to be here to stop the compiler complaining
// Basically the 'default' is run if no other case is run
return PLAYER_IS_OK;
}
}
// Code should never reach this point
// The return line here is just to make the compiler happy
return 0;
}
int play_level(SDL_Renderer* renderer, struct level_struct *currentlevel)
{
// Loop until the user completes the level
int player_status = PLAYER_IS_OK;
while ( player_status == PLAYER_IS_OK )
{
SDL_Event userinput;
// WaitEvent is like PollEvent, but instead we pause the program's
// execution until we get input
SDL_WaitEvent( &userinput );
render(renderer, currentlevel);
// Player movement
signed int y, x;
if ( userinput.type == SDL_KEYDOWN )
{
switch ( userinput.key.keysym.sym )
{
case SDLK_UP:
x = 0;
y = -1;
break;
case SDLK_DOWN:
x = 0;
y = 1;
break;
case SDLK_RIGHT:
x = 1;
y = 0;
break;
case SDLK_LEFT:
x = -1;
y = 0;
break;
case SDLK_q:
exit(0); // Quit the game
break;
case SDLK_h:
// View the help screen
help(renderer);
x = 0;
y = 0;
default:
// The user hits any other key
// ( do nothing )
x = 0;
y = 0;
break;
}
// Now move the player
player_status = player_action( x, y, currentlevel );
// Move all of the echidnas
run_all_echidnaAI_onestep( currentlevel );
// And make sure we open/close red doors if any of them are stepping on red levers
check_echidna_on_switches( currentlevel );
// Check to see if the player has run into an echidna
if ( check_echidna_proximity( currentlevel ) == 1 ) player_status = PLAYER_IS_DEAD;
// Show a losing screen if applicable
if (player_status == PLAYER_IS_DEAD) render_a_losingscreen(renderer, currentlevel);
}
}
// The code running play_level needs to know if too advance to the next level
// or just repeat the current one ( if the player has died )
return player_status;
}
void game_loop(SDL_Renderer* renderer)
{
struct level_struct currentlevel;
level_load_resources(renderer, ¤tlevel ); // load pixmaps
// Initialise initial player face
currentlevel.player_face = 2;
int level_number; // Level's number in progression of game, also used as the filename to load the level from
// Run through each of the levels
for ( level_number = 2; level_number <= 10; level_number++ )
{
int level_state = PLAYER_IS_OK;
while ( level_state != PLAYER_HAS_WON )
{
// Load the level
level_load( level_number, ¤tlevel );
// Set the player's new position
currentlevel.px = currentlevel.sx;
currentlevel.py = currentlevel.sy;
// Main game loop
level_state = play_level(renderer, ¤tlevel);
}
// When the game loop ends, then the user has successfully completed the level, and we can move on
}
// The user has now completed all of the game
// Show them the winning screen
SDL_RenderClear(renderer);
SDL_RenderCopy(renderer, currentlevel.winning_screen, NULL, NULL);
SDL_RenderPresent(renderer);
SDL_Delay(20 * 1000); // 20 * 1000msecs = 20 seconds
// Once this function ends, we return to the menu
}
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