// worldlight.cpp
#include "cube.h"
#import "DynamicEntity.h"
#import "Entity.h"
#import "Monster.h"
#import "Variable.h"
extern bool hasoverbright;
VAR(lightscale, 1, 4, 100);
// done in realtime, needs to be fast
void
lightray(float bx, float by, Entity *light)
{
float lx = light.x + (rnd(21) - 10) * 0.1f;
float ly = light.y + (rnd(21) - 10) * 0.1f;
float dx = bx - lx;
float dy = by - ly;
float dist = (float)sqrt(dx * dx + dy * dy);
if (dist < 1.0f)
return;
int reach = light.attr1;
int steps = (int)(reach * reach * 1.6f /
dist); // can change this for speedup/quality?
const int PRECBITS = 12;
const float PRECF = 4096.0f;
int x = (int)(lx * PRECF);
int y = (int)(ly * PRECF);
int l = light.attr2 << PRECBITS;
int stepx = (int)(dx / (float)steps * PRECF);
int stepy = (int)(dy / (float)steps * PRECF);
// incorrect: light will fade quicker if near edge of the world
int stepl = l / (float)steps;
if (hasoverbright) {
l /= lightscale;
stepl /= lightscale;
// coloured light version, special case because most lights are
// white
if (light.attr3 || light.attr4) {
int dimness = rnd((255 - (light.attr2 + light.attr3 +
light.attr4) / 3) / 16 + 1);
x += stepx * dimness;
y += stepy * dimness;
if (OUTBORD(x >> PRECBITS, y >> PRECBITS))
return;
int g = light.attr3 << PRECBITS;
int stepg = g / (float)steps;
int b = light.attr4 << PRECBITS;
int stepb = b / (float)steps;
g /= lightscale;
stepg /= lightscale;
b /= lightscale;
stepb /= lightscale;
for (int i = 0; i < steps; i++) {
struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
int tl = (l >> PRECBITS) + s->r;
s->r = tl > 255 ? 255 : tl;
tl = (g >> PRECBITS) + s->g;
s->g = tl > 255 ? 255 : tl;
tl = (b >> PRECBITS) + s->b;
s->b = tl > 255 ? 255 : tl;
if (SOLID(s))
return;
x += stepx;
y += stepy;
l -= stepl;
g -= stepg;
b -= stepb;
stepl -= 25;
stepg -= 25;
stepb -= 25;
}
} else // white light, special optimized version
{
int dimness = rnd((255 - light.attr2) / 16 + 1);
x += stepx * dimness;
y += stepy * dimness;
if (OUTBORD(x >> PRECBITS, y >> PRECBITS))
return;
for (int i = 0; i < steps; i++) {
struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
int tl = (l >> PRECBITS) + s->r;
s->r = s->g = s->b = tl > 255 ? 255 : tl;
if (SOLID(s))
return;
x += stepx;
y += stepy;
l -= stepl;
stepl -= 25;
}
}
} else // the old (white) light code, here for the few people with old
// video cards that don't support overbright
{
for (int i = 0; i < steps; i++) {
struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
int light = l >> PRECBITS;
if (light > s->r)
s->r = s->g = s->b = (unsigned char)light;
if (SOLID(s))
return;
x += stepx;
y += stepy;
l -= stepl;
}
}
}
void
calclightsource(Entity *l)
{
int reach = l.attr1;
int sx = l.x - reach;
int ex = l.x + reach;
int sy = l.y - reach;
int ey = l.y + reach;
rndreset();
const float s = 0.8f;
for (float sx2 = (float)sx; sx2 <= ex; sx2 += s * 2) {
lightray(sx2, (float)sy, l);
lightray(sx2, (float)ey, l);
}
for (float sy2 = sy + s; sy2 <= ey - s; sy2 += s * 2) {
lightray((float)sx, sy2, l);
lightray((float)ex, sy2, l);
}
rndtime();
}
// median filter, smooths out random noise in light and makes it more mipable
void
postlightarea(const struct block *a)
{
// assumes area not on edge of world
for (int x = 0; x < a->xs; x++) {
for (int y = 0; y < a->ys; y++) {
struct sqr *s = S(x + a->x, y + a->y);
// median is 4/2/1 instead
#define median(m) \
s->m = (s->m * 2 + SW(s, 1, 0)->m * 2 + SW(s, 0, 1)->m * 2 + \
SW(s, -1, 0)->m * 2 + SW(s, 0, -1)->m * 2 + SW(s, 1, 1)->m + \
SW(s, 1, -1)->m + SW(s, -1, 1)->m + SW(s, -1, -1)->m) / 14;
median(r);
median(g);
median(b);
}
}
remip(a, 0);
}
void
calclight()
{
for (int x = 0; x < ssize; x++) {
for (int y = 0; y < ssize; y++) {
struct sqr *s = S(x, y);
s->r = s->g = s->b = 10;
}
}
for (Entity *e in ents)
if (e.type == LIGHT)
calclightsource(e);
struct block b = { 1, 1, ssize - 2, ssize - 2 };
postlightarea(&b);
setvar(@"fullbright", 0);
}
VARP(dynlight, 0, 16, 32);
static OFMutableData *dlights;
void
cleardlights()
{
while (dlights.count > 0) {
struct block *backup = *(struct block **)[dlights lastItem];
[dlights removeLastItem];
blockpaste(backup);
OFFreeMemory(backup);
}
}
void
dodynlight(OFVector3D vold, OFVector3D v, int reach, int strength,
DynamicEntity *owner)
{
if (!reach)
reach = dynlight;
if ([owner isKindOfClass: Monster.class])
reach = reach / 2;
if (!reach)
return;
if (v.x < 0 || v.y < 0 || v.x > ssize || v.y > ssize)
return;
int creach = reach + 16; // dependant on lightray random offsets!
struct block b = { (int)v.x - creach, (int)v.y - creach, creach * 2 + 1,
creach * 2 + 1 };
if (b.x < 1)
b.x = 1;
if (b.y < 1)
b.y = 1;
if (b.xs + b.x > ssize - 2)
b.xs = ssize - 2 - b.x;
if (b.ys + b.y > ssize - 2)
b.ys = ssize - 2 - b.y;
if (dlights == nil)
dlights = [[OFMutableData alloc]
initWithItemSize: sizeof(struct block *)];
// backup area before rendering in dynlight
struct block *copy = blockcopy(&b);
[dlights addItem: ©];
Entity *l = [Entity entity];
l.x = v.x;
l.y = v.y;
l.z = v.z;
l.attr1 = reach;
l.type = LIGHT;
l.attr2 = strength;
calclightsource(l);
postlightarea(&b);
}
// utility functions also used by editing code
struct block *
blockcopy(const struct block *s)
{
struct block *b = OFAllocZeroedMemory(
1, sizeof(struct block) + s->xs * s->ys * sizeof(struct sqr));
*b = *s;
struct sqr *q = (struct sqr *)(b + 1);
for (int x = s->x; x < s->xs + s->x; x++)
for (int y = s->y; y < s->ys + s->y; y++)
*q++ = *S(x, y);
return b;
}
void
blockpaste(const struct block *b)
{
struct sqr *q = (struct sqr *)(b + 1);
for (int x = b->x; x < b->xs + b->x; x++)
for (int y = b->y; y < b->ys + b->y; y++)
*S(x, y) = *q++;
remipmore(b, 0);
}