typedef struct {
	gp_spr *top,*north,*south,*east,*west; /* The textures for the 5 visible sides */
	int flags; /* Flags */
	f1616 h1,h2; /* Heights of the two edges */
} block;

/* Block flags */
/* This would work better using a proper bitfield type */
#define BLOCK_ROT 3	/* Mask to use when reading/writing rotation of top texture */
#define BLOCK_ROT_NONE 0	/* No rotation */
#define BLOCK_ROT_LEFT 1	/* Rotated left 90 degrees */
#define BLOCK_ROT_RIGHT 2	/* Rotated right 90 degrees */
#define BLOCK_ROT_180 3	/* Rotated 180 degrees */

#define BLOCK_CONTENT 28	/* Mask to use when reading/writing contents of block */
#define BLOCK_CONTENT_AIR 0	/* Block contains air */
#define BLOCK_CONTENT_SOLID 4	/* Solid ground */
#define BLOCK_CONTENT_WATER 8	/* Water */
#define BLOCK_CONTENT_DIRT 12 	/* Grass/dirt */
#define BLOCK_CONTENT_RADIATION 16 /* Deadly radiation */
/* ... etc */

#define BLOCK_SLOPE_HORZ 32	/* h1 & h2 are the heights of the east and west edges of the block,
as opposed to the heights of the north & south edges */
#define BLOCK_PED_PATH 64 /* Pedestrians will try and stick to these blocks */

#define BLOCK_ROAD_NORTH 128 /* Road goes north */
#define BLOCK_ROAD_SOUTH 256 /* Road goes sorth */
#define BLOCK_ROAD_EAST 512 /* Road goes east */
#define BLOCK_ROAD_WEST 1024 /* Road goes west */
/* Set multiple flags to create junctions */

#define BLOCK_WALL_NORTH 2048 /* Flags to control if the north/west sides of the block are solid */
#define BLOCK_WALL_WEST 4096 /* e.g. to create a solid fence between two blocks */
#define BLOCK_WALL_TOP 8192 /* Top side is solid, useful if the block below must contain air */

typedef struct {
	int height; /* Number of blocks in the stack */
	block *b[0]; /* Blocks (Using GCC variable length array wotsit) */
} stack;

typedef struct {
	f1616 base; /* Base of the bottom block in the stack */
	stack *s; /* The stack */
} stack2;

typedef struct {
	int width,height; /* Map size in blocks */
	stack2 m[0]; /* width*height array of block stacks */
} map;

int contenttype(map *m,f1616 x,f1616 y,f1616 z)
{
	int ix,iy,iz;
	stack *s;
	stack2 *s2;
	/* Get integer coords & apply limits */
	ix = x >> 16;
	iy = y >> 16;
	if (ix < 0)
		ix = 0;
	else if (ix >= m->width)
		ix = m->width-1;
	if (iy < 0)
		iy = 0;
	else if (iy >= m->height)
		iy = m->height-1;
	/* Get stack data */
	s2 = &(m->m[ix+iy*m->width]);
	/* Get index into stack */
	z = z-s2->base;
	if (z < 0)
		iz = z = 0;
	else
		iz = z >> 16;
	s = s2->s;
	if (iz >= s->height)
		iz = s->height-1;
	/* Examine slope data in the block */
	x &= 0xFFFF;
	y &= 0xFFFF;
	z &= 0xFFFF;
	if ((z > s->b[iz]->h1) && (z > s->b[iz]->h2)) { /* Above the surface? */
		if (iz == s->height-1)
			return BLOCK_CONTENT_AIR; /* Assume everything above the map is air */
		else
			return s->b[iz+1]->flags & BLOCK_CONTENT; /* Return content of the next block up */
	} else if ((z <= s->b[iz]->h1) && (z <= s->b[iz]->h2)) /* Below the surface? */
		return s->b[iz]->flags & BLOCK_CONTENT; /* Return the content of this block */
	else if (s->b[iz]->flags & BLOCK_SLOPE_HORZ) /* We are in the sloping section */
		x = s->b[iz]->h1+f1616_mul(s->b[iz]->h2-s->b[iz]->h1,x); /* Surface height at our coords */
	else
		x = s->b[iz]->h1+f1616_mul(s->b[iz]->h2-s->b[iz]->h1,y);
	if (z <= x)
		return s->b[iz]->flags & BLOCK_CONTENT;
	else if (iz == s->height-1)
		return BLOCK_CONTENT_AIR;
	else
		return s->b[iz+1]->flags & BLOCK_CONTENT;
}

Why do you want such a deep map?

Won't it affect (reduce) the playablility?

If not, how will it improve the game?

[Snipped feckin huge quote - RG]

Yes. You're a genius.

Also, what exactly does ray casting mean? Calculate a distance based on stored coordinates? Always wondered this.

[snip game world description]

this sounds a bit like flashback

; R0=Source 8bpp
; R1=Dest 16bpp
; R2=Number of pixels in image
; R3=Palette ptr
.loop
LDRB R4,[R0],#1
MOVS R4,R4,LSL #1 ; Using index 0 for real-mask
LDRNEB R5,[R4,R3]!
LDRNEB R6,[R4,#1]
STRNEB R5,[R1],#1
STRNEB R6,[R1],#1
ADDEQ R1,R1,#2
SUBS R2,R2,#1
BNE loop

So presumably (because I only understood about half of that ) you draw the car in one direction, and rotate it as you need it?

How many rotations (16? 32? more?)? Do you have to cache loads of rotations?

16bpp

So presumably (because I only understood about half of that ) you draw the car in one direction, and rotate it as you need it? How many rotations (16? 32? more?)? Do you have to cache loads of rotations?

Which bits didn't you understand btw? I could probably rewrite it to make it clearer.

Cheers,
Rich.

Which bits didn't you understand btw? I could probably rewrite it to make it clearer.

The bits where my brain isn't set up to handle technical stuff? Which is pretty much all of it.

Please rewrite the entire thread with single syllable words using only concepts I'll understand

Please rewrite the entire thread with single syllable words using only concepts I'll understand

-ol

99 ammo max? You're 'avin a larf aintcha? That's only three and a third clips for an SMG (e.g. MP5) or automatic rifle (e.g. M16). It's less than two clips for a P90 (SMG)!

Add at least one extra digit. Or make a distinction between hand guns and larger weapons.

99 ammo max? You're 'avin a larf aintcha? That's only three and a third clips for an SMG (e.g. MP5) or automatic rifle (e.g. M16). It's less than two clips for a P90 (SMG)!

Add at least one extra digit. Or make a distinction between hand guns and larger weapons.

Add at least one extra digit. Or make a distinction between hand guns and larger weapons.

99 ammo seems plenty, considering that most people you'd want to shoot will be armed with a gun, thus allowing you to collect their ammo once you've killed them. For zombies and stuff you can use infinite ammo weapons (chainsaws!). Or just run the buggers over. It's a little thing called strategy

Cheers,
Rich.

The GTA series I've played (admittedly from 3 onwards) I usually like to have around 1000 rounds for any automatic weaponry. Then when a gang comes after you, you can hole up and pick them off without breaking cover. That's strategy.

Why do you want such a deep map?

So I can have big buildings, mountains, and levels which gradually get higher (or lower) the further you travel from one side to another.

Won't it affect (reduce) the playablility?

How could it?

In that case wouldn't a heightmap be useful? OK, so you'd still need stacks if you wanted tall buildings or steep slopes.

Won't it affect (reduce) the playablility?

How could it?

Well if you can be at the same (x,y) but at many different heights, I find it tends to be confusing. And this buggers the gameplay.

I may have misunderstood your description...
Probably around 2 or 3 possible heights max, with the average being close to 1 would be OK. Depending on the circumstances you use the stack in, and your display method, you may be able to have more possible heights I suppose.

Since you have a limited number of stack types (presumably around 256) you probably don't want them to be too complicated anyway.

Since each pedestrian is going to be cached separately, why not stack clothing etc. on them like you have cars? I like your forced mask idea, incidentally.

Regarding ammo, perhaps you could make it really scarce, so that the 99 limit wasn't significant. Like in the film Mad Max 2.

Why 99 anyway? so it can be displayed as 2 digits?