X-Git-Url: https://git.xonotic.org/?a=blobdiff_plain;f=misc%2Ftools%2Fspherefunc2skybox.c;h=201cefb955c5446652816170cb0f56b83f355df1;hb=611be7dbdb01ee7206e1e52dba0c54596c76a92f;hp=3e3e7a5ad007bed931add27f01fcdee1233521d3;hpb=e5832bf2ecac60a672a29c85cd8dec341a215e1c;p=xonotic%2Fxonotic.git

diff --git a/misc/tools/spherefunc2skybox.c b/misc/tools/spherefunc2skybox.c
index 3e3e7a5a..201cefb9 100644
--- a/misc/tools/spherefunc2skybox.c
+++ b/misc/tools/spherefunc2skybox.c
@@ -141,6 +141,110 @@ void color_mandelbrot(double x, double y, double z, double *r, double *g, double
 	*b = pow(iterations, color_mandelbrot_parms[12]);
 }
 
+struct
+{
+	int n;
+	double darkness;
+	double power;
+	double density;
+	int g;
+	double gpower;
+	double gfactor;
+	double gdpower;
+}
+color_starfield_parms;
+typedef struct
+{
+	double x, y, z, e;
+	double R, G, B, A;
+} starfield_t;
+starfield_t *starfield = NULL;
+int starfield_cmp(const void *a_, const void *b_)
+{
+	const starfield_t *a = a_;
+	const starfield_t *b = b_;
+	if(a->z < b->z)
+		return -1;
+	if(a->z > b->z)
+		return +1;
+	return 0;
+}
+void color_starfield(double x, double y, double z, double *r, double *g, double *b)
+{
+	int i, j, k;
+	double f, mindot, d;
+
+	if(!starfield)
+	{
+		fprintf(stderr, "Initializing starfield...\n");
+		starfield = malloc(sizeof(*starfield) * color_starfield_parms.n);
+		for(i = 0; i < color_starfield_parms.n; ++i)
+		{
+			double r;
+			do
+			{
+				starfield[i].x = rnd() * 2 - 1;
+				starfield[i].y = rnd() * 2 - 1;
+				starfield[i].z = rnd() * 2 - 1;
+				r = starfield[i].x * starfield[i].x
+				  + starfield[i].y * starfield[i].y
+				  + starfield[i].z * starfield[i].z;
+			}
+			while(r > 1);
+
+			starfield[i].R = rnd();
+			starfield[i].G = rnd();
+			starfield[i].B = rnd();
+			f = starfield[i].R * 0.299 + starfield[i].G * 0.587 + starfield[i].B * 0.114;
+			starfield[i].R /= f;
+			starfield[i].G /= f;
+			starfield[i].B /= f;
+			starfield[i].A = rnd();
+			starfield[i].e = color_starfield_parms.density * pow(rnd(), -color_starfield_parms.power);
+		}
+		fprintf(stderr, "Gravitating starfield...\n");
+		for(k = 0; k < color_starfield_parms.g; ++k)
+		{
+			i = rand() % color_starfield_parms.n;
+			j = rand() % color_starfield_parms.n;
+			f = pow(rnd(), color_starfield_parms.gpower);
+			f = f * color_starfield_parms.gfactor;
+			d = pow(starfield[j].x - starfield[i].x, 2)
+			  + pow(starfield[j].y - starfield[i].y, 2)
+			  + pow(starfield[j].z - starfield[i].z, 2);
+			f *= pow(1 / (1 + d), color_starfield_parms.gdpower);
+			starfield[i].x += f * (starfield[j].x - starfield[i].x);
+			starfield[i].y += f * (starfield[j].y - starfield[i].y);
+			starfield[i].z += f * (starfield[j].z - starfield[i].z);
+			double r = starfield[i].x * starfield[i].x + starfield[i].y * starfield[i].y + starfield[i].z * starfield[i].z;
+			r = sqrt(r);
+			starfield[i].x /= r;
+			starfield[i].y /= r;
+			starfield[i].z /= r;
+		}
+		fprintf(stderr, "Sorting starfield...\n");
+		qsort(starfield, sizeof(*starfield), color_starfield_parms.n, starfield_cmp);
+		fprintf(stderr, "Done.\n");
+	}
+
+	*r = *g = *b = 0;
+	mindot = pow(1/256.0, 1.0/color_starfield_parms.density);
+	for(i = 0; i < color_starfield_parms.n; ++i)
+	{
+		double dot = x * starfield[i].x + y * starfield[i].y + z * starfield[i].z;
+		if(dot <= mindot)
+			continue;
+		double f = pow(dot, starfield[i].e) * starfield[i].A;
+		*r += starfield[i].R * f;
+		*g += starfield[i].G * f;
+		*b += starfield[i].B * f;
+	}
+	// make fit in 0..1
+	*r = *r / (color_starfield_parms.darkness + *r);
+	*g = *g / (color_starfield_parms.darkness + *g);
+	*b = *b / (color_starfield_parms.darkness + *b);
+}
+
 void map_back(double x_in, double y_in, double *x_out, double *y_out, double *z_out)
 {
 	*x_out = 2 * x_in - 1;
@@ -187,6 +291,7 @@ void writepic(colorfunc_t f, mapfunc_t m, const char *fn, int width, int height)
 {
 	int x, y;
 	uint8_t tga[18];
+	int percent, p;
 
 	FILE *file = fopen(fn, "wb");
 	if(!file)
@@ -201,7 +306,9 @@ void writepic(colorfunc_t f, mapfunc_t m, const char *fn, int width, int height)
 	tga[16] = 24;        // pixel size
 
 	fwrite(&tga, sizeof(tga), 1, file);
+	percent = 0;
 	for(y = height-1; y >= 0; --y)
+	{
 		for(x = 0; x < width; ++x)
 		{
 			uint8_t rgb[3];
@@ -222,6 +329,14 @@ void writepic(colorfunc_t f, mapfunc_t m, const char *fn, int width, int height)
 			rgb[0] = floor(rnd() + bb * 255);
 			fwrite(rgb, sizeof(rgb), 1, file);
 		}
+		p = (100 * (height - y)) / height;
+		if(p != percent)
+		{
+			percent = p;
+			fprintf(stderr, "%d%%\r", percent);
+		}
+	}
+	fprintf(stderr, "\n");
 	
 	fclose(file);
 }
@@ -229,11 +344,17 @@ void writepic(colorfunc_t f, mapfunc_t m, const char *fn, int width, int height)
 void map_all(const char *fn, colorfunc_t f, int width, int height)
 {
 	char buf[1024];
+	fprintf(stderr, "%s_bk.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_bk.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_back, buf, width, height);
+	fprintf(stderr, "%s_ft.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_ft.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_front, buf, width, height);
+	fprintf(stderr, "%s_rt.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_rt.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_right, buf, width, height);
+	fprintf(stderr, "%s_lf.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_lf.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_left, buf, width, height);
+	fprintf(stderr, "%s_up.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_up.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_up, buf, width, height);
+	fprintf(stderr, "%s_dn.tga\n", fn);
 	snprintf(buf, sizeof(buf), "%s_dn.tga", fn); buf[sizeof(buf) - 1] = 0; writepic(f, map_down, buf, width, height);
 }
 
@@ -260,10 +381,22 @@ int main(int argc, char **argv)
 		color_mandelbrot_parms[11] = argc<=15 ?   0.5   : atof(argv[15]);
 		color_mandelbrot_parms[12] = argc<=16 ?   0.2   : atof(argv[16]);
 	}
+	else if(!strcmp(argv[3], "starfield"))
+	{
+		f = color_starfield;
+		color_starfield_parms.n = argc<= 4 ? 8192 : atoi(argv[4]);
+		color_starfield_parms.darkness = argc<= 5 ? 0.4 : atof(argv[5]);
+		color_starfield_parms.power = argc<= 6 ? 2.5 : atof(argv[6]);
+		color_starfield_parms.density = argc<= 7 ? 60000 : atof(argv[7]);
+		color_starfield_parms.g = argc<= 8 ? 10000000 : atoi(argv[8]);
+		color_starfield_parms.gpower = argc<= 9 ? 3 : atoi(argv[9]);
+		color_starfield_parms.gfactor = argc<= 10 ? 0.9 : atof(argv[10]);
+		color_starfield_parms.gdpower = argc<= 11 ? 15 : atof(argv[11]);
+	}
 	else
 	{
 		f = color_test;
 	}
-	map_all(argv[1], color_mandelbrot, res, res);
+	map_all(argv[1], f, res, res);
 	return 0;
 }