Class-ify caves & move to cavegen.cpp, fix cave regression, add caves to Mapgen V7

1 files changed, 266 insertions, 0 deletions

diff --git a/src/cavegen.cpp b/src/cavegen.cpp
new file mode 100644
index 000000000..bef50c7a7
--- /dev/null
+++ b/src/cavegen.cpp
@@ -0,0 +1,266 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "util/numeric.h"
+#include "map.h"
+#include "mapgen.h"
+#include "cavegen.h"
+
+
+CaveV6::CaveV6(Mapgen *mg, PseudoRandom *ps, PseudoRandom *ps2,
+			bool is_large_cave, content_t c_water, content_t c_lava) {
+	this->vm = mg->vm;
+	this->water_level = mg->water_level;
+	this->large_cave = is_large_cave;
+	this->ps  = ps;
+	this->ps2 = ps2;
+	this->c_water_source = c_water;
+	this->c_lava_source  = c_lava;
+
+	min_tunnel_diameter = 2;
+	max_tunnel_diameter = ps->range(2, 6);
+	dswitchint = ps->range(1, 14);
+	flooded = true;
+	
+	if (large_cave) {
+		part_max_length_rs = ps->range(2,4);
+		tunnel_routepoints = ps->range(5, ps->range(15,30));
+		min_tunnel_diameter = 5;
+		max_tunnel_diameter = ps->range(7, ps->range(8,24));
+	} else {
+		part_max_length_rs = ps->range(2,9);
+		tunnel_routepoints = ps->range(10, ps->range(15,30));
+	}
+	
+	large_cave_is_flat = (ps->range(0,1) == 0);
+}
+
+
+void CaveV6::makeCave(v3s16 nmin, v3s16 nmax, int max_stone_height) {
+	node_min = nmin;
+	node_max = nmax;
+	max_stone_y = max_stone_height;
+	main_direction = v3f(0, 0, 0);
+
+	// Allowed route area size in nodes
+	ar = node_max - node_min + v3s16(1, 1, 1);
+	// Area starting point in nodes
+	of = node_min;
+
+	// Allow a bit more
+	//(this should be more than the maximum radius of the tunnel)
+	const s16 max_spread_amount = MAP_BLOCKSIZE;
+	s16 insure = 10;
+	s16 more = max_spread_amount - max_tunnel_diameter / 2 - insure;
+	ar += v3s16(1,0,1) * more * 2;
+	of -= v3s16(1,0,1) * more;
+
+	route_y_min = 0;
+	// Allow half a diameter + 7 over stone surface
+	route_y_max = -of.Y + max_stone_y + max_tunnel_diameter / 2 + 7;
+
+	// Limit maximum to area
+	route_y_max = rangelim(route_y_max, 0, ar.Y - 1);
+
+	if (large_cave) {
+		s16 min = 0;
+		if (node_min.Y < water_level && node_max.Y > water_level) {
+			min = water_level - max_tunnel_diameter/3 - of.Y;
+			route_y_max = water_level + max_tunnel_diameter/3 - of.Y;
+		}
+		route_y_min = ps->range(min, min + max_tunnel_diameter);
+		route_y_min = rangelim(route_y_min, 0, route_y_max);
+	}
+
+	s16 route_start_y_min = route_y_min;
+	s16 route_start_y_max = route_y_max;
+
+	route_start_y_min = rangelim(route_start_y_min, 0, ar.Y-1);
+	route_start_y_max = rangelim(route_start_y_max, route_start_y_min, ar.Y-1);
+
+	// Randomize starting position
+	orp = v3f(
+		(float)(ps->next() % ar.X) + 0.5,
+		(float)(ps->range(route_start_y_min, route_start_y_max)) + 0.5,
+		(float)(ps->next() % ar.Z) + 0.5
+	);
+
+	// Generate some tunnel starting from orp
+	for (u16 j = 0; j < tunnel_routepoints; j++)
+		makeTunnel(j % dswitchint == 0);
+}
+
+
+void CaveV6::makeTunnel(bool dirswitch) {
+	if (dirswitch && !large_cave) {
+		main_direction = v3f(
+			((float)(ps->next() % 20) - (float)10) / 10,
+			((float)(ps->next() % 20) - (float)10) / 30,
+			((float)(ps->next() % 20) - (float)10) / 10
+		);
+		main_direction *= (float)ps->range(0, 10) / 10;
+	}
+
+	// Randomize size
+	s16 min_d = min_tunnel_diameter;
+	s16 max_d = max_tunnel_diameter;
+	rs = ps->range(min_d, max_d);
+
+	v3s16 maxlen;
+	if (large_cave) {
+		maxlen = v3s16(
+			rs * part_max_length_rs,
+			rs * part_max_length_rs / 2,
+			rs * part_max_length_rs
+		);
+	} else {
+		maxlen = v3s16(
+			rs * part_max_length_rs,
+			ps->range(1, rs * part_max_length_rs),
+			rs * part_max_length_rs
+		);
+	}
+
+	v3f vec(
+		(float)(ps->next() % (maxlen.X * 1)) - (float)maxlen.X / 2,
+		(float)(ps->next() % (maxlen.Y * 1)) - (float)maxlen.Y / 2,
+		(float)(ps->next() % (maxlen.Z * 1)) - (float)maxlen.Z / 2
+	);
+
+	// Jump downward sometimes
+	if (!large_cave && ps->range(0, 12) == 0) {
+		vec = v3f(
+			(float)(ps->next() % (maxlen.X * 1)) - (float)maxlen.X / 2,
+			(float)(ps->next() % (maxlen.Y * 2)) - (float)maxlen.Y,
+			(float)(ps->next() % (maxlen.Z * 1)) - (float)maxlen.Z / 2
+		);
+	}
+
+	/*if(large_cave){
+		v3f p = orp + vec;
+		s16 h = find_ground_level_clever(vmanip, v2s16(p.X, p.Z), ndef);
+		route_y_min = h - rs/3;
+		route_y_max = h + rs;
+	}*/
+
+	vec += main_direction;
+
+	v3f rp = orp + vec;
+	if (rp.X < 0)
+		rp.X = 0;
+	else if (rp.X >= ar.X)
+		rp.X = ar.X - 1;
+	
+	if (rp.Y < route_y_min)
+		rp.Y = route_y_min;
+	else if (rp.Y >= route_y_max)
+		rp.Y = route_y_max - 1;
+	
+	if (rp.Z < 0)
+		rp.Z = 0;
+	else if (rp.Z >= ar.Z)
+		rp.Z = ar.Z - 1;
+	
+	vec = rp - orp;
+
+	float veclen = vec.getLength();
+	// As odd as it sounds, veclen is *exactly* 0.0 sometimes, causing a FPE
+	if (veclen == 0.0)
+		veclen = 1.0;
+		
+	// Every second section is rough
+	bool randomize_xz = (ps2->range(1, 2) == 1);
+
+	// Carve routes
+	for (float f = 0; f < 1.0; f += 1.0 / veclen)
+		carveRoute(vec, f, randomize_xz);
+	
+	orp = rp;
+}
+
+
+void CaveV6::carveRoute(v3f vec, float f, bool randomize_xz) {
+	MapNode airnode(CONTENT_AIR);
+	MapNode waternode(c_water_source);
+	MapNode lavanode(c_lava_source);
+	
+	v3s16 startp(orp.X, orp.Y, orp.Z);
+	startp += of;
+	
+	v3f fp = orp + vec * f;
+	fp.X += 0.1 * ps->range(-10, 10);
+	fp.Z += 0.1 * ps->range(-10, 10);
+	v3s16 cp(fp.X, fp.Y, fp.Z);
+
+	s16 d0 = -rs/2;
+	s16 d1 = d0 + rs;
+	if (randomize_xz) {
+		d0 += ps->range(-1, 1);
+		d1 += ps->range(-1, 1);
+	}
+	
+	for (s16 z0 = d0; z0 <= d1; z0++) {
+		s16 si = rs / 2 - MYMAX(0, abs(z0) - rs / 7 - 1);
+		for (s16 x0 = -si - ps->range(0,1); x0 <= si - 1 + ps->range(0,1); x0++) {
+			s16 maxabsxz = MYMAX(abs(x0), abs(z0));
+			s16 si2 = rs / 2 - MYMAX(0, maxabsxz - rs / 7 - 1);
+			for (s16 y0 = -si2; y0 <= si2; y0++) {
+				// Make better floors in small caves
+				//if(y0 <= -rs/2 && rs<=7)
+				//	continue;
+				
+				if (large_cave_is_flat) {
+					// Make large caves not so tall
+					if (rs > 7 && abs(y0) >= rs / 3)
+						continue;
+				}
+
+				v3s16 p(cp.X + x0, cp.Y + y0, cp.Z + z0);
+				p += of;
+
+				if (vm->m_area.contains(p) == false)
+					continue;
+
+				u32 i = vm->m_area.index(p);
+
+				if (large_cave) {
+					int full_ymin = node_min.Y - MAP_BLOCKSIZE;
+					int full_ymax = node_max.Y + MAP_BLOCKSIZE;
+					
+					if (flooded && full_ymin < water_level && full_ymax > water_level) {
+						vm->m_data[i] = (p.Y <= water_level) ? waternode : airnode;
+					} else if (flooded && full_ymax < water_level) {
+						vm->m_data[i] = (p.Y < startp.Y - 2) ? lavanode : airnode;
+					} else {
+						vm->m_data[i] = airnode;
+					}
+				} else {
+					// Don't replace air or water or lava or ignore
+					content_t c = vm->m_data[i].getContent();
+					if (c == CONTENT_IGNORE || c == CONTENT_AIR ||
+						c == c_water_source || c == c_lava_source)
+						continue;
+
+					vm->m_data[i] = airnode;
+					vm->m_flags[i] |= VMANIP_FLAG_CAVE;
+				}
+			}
+		}
+	}
+}