added comments

1 files changed, 27 insertions, 1 deletions

diff --git a/mapgen.c b/mapgen.c
index f18df4d..6b169c4 100644
--- a/mapgen.c
+++ b/mapgen.c
@@ -4,6 +4,9 @@
 #include "hardware.h"

 #include "sprites.h"

 

+// this code is a random map generator based on the kill and hunt algorithm

+

+// this counts unempty neighbours

 static int cntunvisit(union st_field cnt)

 {

 	int c = 0;

@@ -15,6 +18,7 @@ static int cntunvisit(union st_field cnt)
 	return (c > 1)?c:0;

 }

 

+// count empty ones, including ones that are outside which are counted as wall

 static int cntempty(int x, int y)

 {

 	union st_field c;

@@ -35,6 +39,7 @@ static int cntempty(int x, int y)
 	return cnt;

 }

 

+// count walls

 static int cntwall(int x, int y)

 {

 	union st_field c;

@@ -55,6 +60,7 @@ static int cntwall(int x, int y)
 	return cnt;

 }

 

+// return as st_field from map point

 static union st_field get(int x, int y)

 {

 	union st_field c;

@@ -69,6 +75,7 @@ static union st_field get(int x, int y)
 	return c;

 }

 

+// try to find a wall with unvisited neighbours

 static int hunt(int *x, int *y)

 {

 	for(*x = 1; *x < MAPSIZE - 1; *x+=2)

@@ -84,6 +91,7 @@ static int hunt(int *x, int *y)
 			}

 		}

 	}

+	// if there is none, we can start the main game

 	return FALSE;

 }

 

@@ -94,6 +102,7 @@ static int kill(int *x, int *y, union st_field this)
 	{

 		if(cntunvisit(this) == 0)fail1 = fail2 = fail3 = fail4 = TRUE;

 		

+		// try to 'digg' in random directions

 		switch(random() % 4)

 		{

 			case 0:

@@ -179,12 +188,15 @@ static int kill(int *x, int *y, union st_field this)
 		

 		if(fail1 == TRUE && fail2 == TRUE && fail3 == TRUE && fail4 == TRUE)

 		{

+			// dead end, try to find a new starting point

 			return hunt(x, y);

 		}

 	}

+	// no possible move left, let's go and kill some robots

 	return FALSE;

 }

 

+// see if we can walk through that maze

 static int solve()

 {

 	int priotable[4];

@@ -193,6 +205,7 @@ static int solve()
 	int deltax = 1, deltay = 0;

 	int dir, dirx, diry;

 start:

+	// that's dirty, I know, but it works

 	for(curx = 0; curx < MAPSIZE; curx++)

 	{

 		for(cury = 0; cury < MAPSIZE; cury++)

@@ -236,6 +249,7 @@ start:
 				dir = WEST;

 		}

 		

+		// this is called the right-hand method, I think

 		switch(dir)

 		{

 			case NORTH:

@@ -263,6 +277,7 @@ start:
 				priotable[3] = EAST;

 		}

 		

+		// try again with left-hand :D

 		for(dir = 0; dir < 4; dir++)

 		{

 			switch(priotable[dir])

@@ -294,12 +309,15 @@ start:
 			}

 		}

 		

+		// we are at the start again?

 		if(curx == 1 && cury == 1)

 		{

+			// this maze has no exit, make another one

 			return FALSE;

 		}

 		

-		if(IsEmulator())

+		// debug only

+		if(IsEmulator)

 		{

 			clear_vram();

 			drawgenmap();

@@ -308,6 +326,7 @@ start:
 		}

 	}

 	

+	// make changes permanent

 	for(curx = 0; curx < MAPSIZE; curx++)

 	{

 		for(cury = 0; cury < MAPSIZE; cury++)

@@ -325,6 +344,7 @@ start:
 		}

 	}

 	

+	// create packs in dead-ends

 	for(curx = 0; curx < MAPSIZE; curx++)

 	{

 		for(cury = 0; cury < MAPSIZE; cury++)

@@ -348,6 +368,7 @@ start:
 			}

 			else if(map[curx][cury] == WALL)

 			{

+				// reduce the height of low walls, this gives a nice effect

 				if(cntwall(curx, cury) == 2)

 				{

 					heights[curx][cury] = 32;

@@ -362,6 +383,7 @@ start:
 		{

 			if(map[curx][cury] == SPACE && cntwall(curx, cury) < 2)

 			{

+				// it is easier with some doors that connect two floors

 				int dx, dy, fail1, fail2, fail3, fail4;

 				fail1 = fail2 = fail3 = fail4 = FALSE;

 				

@@ -395,13 +417,17 @@ start:
 	return TRUE;

 }

 

+// main loop

 void maze()

 {

 	do

 	{

 		int x = 1, y = 1, exit = TRUE;

 

+		// create an empty map

 		fill(&map, WALL, MAPSIZE * MAPSIZE);

+		

+		// render it until it is solvable

 		while(exit == TRUE)

 		{

 			map[x][y] = SPACE;