X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Futil%2Fnumeric.cpp;h=cb984d8cb5b60879f7f11bb158c2162afca11848;hb=67a4cb7d8a4461fe7d5206189fd4e9539beb20b7;hp=67df4ffbafe0bf8cfdb201ae3084057cc5e5af3e;hpb=39ab22070e912b328b021731be8e1d983a2124ff;p=minetest.git

diff --git a/src/util/numeric.cpp b/src/util/numeric.cpp
index 67df4ffba..cb984d8cb 100644
--- a/src/util/numeric.cpp
+++ b/src/util/numeric.cpp
@@ -18,138 +18,100 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #include "numeric.h"
-#include "mathconstants.h"
 
-#include "../log.h"
-#include "../constants.h" // BS, MAP_BLOCKSIZE
-#include <iostream>
+#include "log.h"
+#include "constants.h" // BS, MAP_BLOCKSIZE
+#include "noise.h" // PseudoRandom, PcgRandom
+#include "threading/mutex_auto_lock.h"
+#include <cstring>
+#include <cmath>
 
-// Calculate the borders of a "d-radius" cube
-void getFacePositions(std::list<v3s16> &list, u16 d)
-{
-	if(d == 0)
-	{
-		list.push_back(v3s16(0,0,0));
-		return;
-	}
-	if(d == 1)
-	{
-		/*
-			This is an optimized sequence of coordinates.
-		*/
-		list.push_back(v3s16( 0, 1, 0)); // top
-		list.push_back(v3s16( 0, 0, 1)); // back
-		list.push_back(v3s16(-1, 0, 0)); // left
-		list.push_back(v3s16( 1, 0, 0)); // right
-		list.push_back(v3s16( 0, 0,-1)); // front
-		list.push_back(v3s16( 0,-1, 0)); // bottom
-		// 6
-		list.push_back(v3s16(-1, 0, 1)); // back left
-		list.push_back(v3s16( 1, 0, 1)); // back right
-		list.push_back(v3s16(-1, 0,-1)); // front left
-		list.push_back(v3s16( 1, 0,-1)); // front right
-		list.push_back(v3s16(-1,-1, 0)); // bottom left
-		list.push_back(v3s16( 1,-1, 0)); // bottom right
-		list.push_back(v3s16( 0,-1, 1)); // bottom back
-		list.push_back(v3s16( 0,-1,-1)); // bottom front
-		list.push_back(v3s16(-1, 1, 0)); // top left
-		list.push_back(v3s16( 1, 1, 0)); // top right
-		list.push_back(v3s16( 0, 1, 1)); // top back
-		list.push_back(v3s16( 0, 1,-1)); // top front
-		// 18
-		list.push_back(v3s16(-1, 1, 1)); // top back-left
-		list.push_back(v3s16( 1, 1, 1)); // top back-right
-		list.push_back(v3s16(-1, 1,-1)); // top front-left
-		list.push_back(v3s16( 1, 1,-1)); // top front-right
-		list.push_back(v3s16(-1,-1, 1)); // bottom back-left
-		list.push_back(v3s16( 1,-1, 1)); // bottom back-right
-		list.push_back(v3s16(-1,-1,-1)); // bottom front-left
-		list.push_back(v3s16( 1,-1,-1)); // bottom front-right
-		// 26
-		return;
-	}
 
-	// Take blocks in all sides, starting from y=0 and going +-y
-	for(s16 y=0; y<=d-1; y++)
-	{
-		// Left and right side, including borders
-		for(s16 z=-d; z<=d; z++)
-		{
-			list.push_back(v3s16(d,y,z));
-			list.push_back(v3s16(-d,y,z));
-			if(y != 0)
-			{
-				list.push_back(v3s16(d,-y,z));
-				list.push_back(v3s16(-d,-y,z));
-			}
-		}
-		// Back and front side, excluding borders
-		for(s16 x=-d+1; x<=d-1; x++)
-		{
-			list.push_back(v3s16(x,y,d));
-			list.push_back(v3s16(x,y,-d));
-			if(y != 0)
-			{
-				list.push_back(v3s16(x,-y,d));
-				list.push_back(v3s16(x,-y,-d));
-			}
-		}
-	}
+// myrand
 
-	// Take the bottom and top face with borders
-	// -d<x<d, y=+-d, -d<z<d
-	for(s16 x=-d; x<=d; x++)
-	for(s16 z=-d; z<=d; z++)
-	{
-		list.push_back(v3s16(x,-d,z));
-		list.push_back(v3s16(x,d,z));
-	}
-}
-
-/*
-    myrand
-*/
+PcgRandom g_pcgrand;
 
-static unsigned long next = 1;
+u32 myrand()
+{
+	return g_pcgrand.next();
+}
 
-/* RAND_MAX assumed to be 32767 */
-int myrand(void)
+void mysrand(unsigned int seed)
 {
-   next = next * 1103515245 + 12345;
-   return((unsigned)(next/65536) % 32768);
+	g_pcgrand.seed(seed);
 }
 
-void mysrand(unsigned seed)
+void myrand_bytes(void *out, size_t len)
 {
-   next = seed;
+	g_pcgrand.bytes(out, len);
 }
 
 int myrand_range(int min, int max)
 {
-	if(max-min > MYRAND_MAX)
-	{
-		errorstream<<"WARNING: myrand_range: max-min > MYRAND_MAX"<<std::endl;
-        max = min + MYRAND_MAX;
+	return g_pcgrand.range(min, max);
+}
+
+
+/*
+	64-bit unaligned version of MurmurHash
+*/
+u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed)
+{
+	const u64 m = 0xc6a4a7935bd1e995ULL;
+	const int r = 47;
+	u64 h = seed ^ (len * m);
+
+	const u64 *data = (const u64 *)key;
+	const u64 *end = data + (len / 8);
+
+	while (data != end) {
+		u64 k;
+		memcpy(&k, data, sizeof(u64));
+		data++;
+
+		k *= m;
+		k ^= k >> r;
+		k *= m;
+
+		h ^= k;
+		h *= m;
 	}
-	if(min > max)
-	{
-		errorstream<<"WARNING: myrand_range: min > max"<<std::endl;
-		return max;
+
+	const unsigned char *data2 = (const unsigned char *)data;
+	switch (len & 7) {
+		case 7: h ^= (u64)data2[6] << 48;
+		case 6: h ^= (u64)data2[5] << 40;
+		case 5: h ^= (u64)data2[4] << 32;
+		case 4: h ^= (u64)data2[3] << 24;
+		case 3: h ^= (u64)data2[2] << 16;
+		case 2: h ^= (u64)data2[1] << 8;
+		case 1: h ^= (u64)data2[0];
+				h *= m;
 	}
-	return (myrand()%(max-min+1))+min;
+
+	h ^= h >> r;
+	h *= m;
+	h ^= h >> r;
+
+	return h;
 }
 
 /*
-	blockpos: position of block in block coordinates
+	blockpos_b: position of block in block coordinates
 	camera_pos: position of camera in nodes
 	camera_dir: an unit vector pointing to camera direction
 	range: viewing range
+	distance_ptr: return location for distance from the camera
 */
 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
 		f32 camera_fov, f32 range, f32 *distance_ptr)
 {
+	// Maximum radius of a block.  The magic number is
+	// sqrt(3.0) / 2.0 in literal form.
+	const f32 block_max_radius = 0.866025403784 * MAP_BLOCKSIZE * BS;
+
 	v3s16 blockpos_nodes = blockpos_b * MAP_BLOCKSIZE;
-	
+
 	// Block center position
 	v3f blockpos(
 			((float)blockpos_nodes.X + MAP_BLOCKSIZE/2) * BS,
@@ -161,22 +123,18 @@ bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
 	v3f blockpos_relative = blockpos - camera_pos;
 
 	// Total distance
-	f32 d = blockpos_relative.getLength();
+	f32 d = MYMAX(0, blockpos_relative.getLength() - block_max_radius);
 
 	if(distance_ptr)
 		*distance_ptr = d;
-	
+
 	// If block is far away, it's not in sight
 	if(d > range)
 		return false;
 
-	// Maximum radius of a block.  The magic number is
-	// sqrt(3.0) / 2.0 in literal form.
-	f32 block_max_radius = 0.866025403784 * MAP_BLOCKSIZE * BS;
-	
 	// If block is (nearly) touching the camera, don't
 	// bother validating further (that is, render it anyway)
-	if(d < block_max_radius)
+	if(d == 0)
 		return true;
 
 	// Adjust camera position, for purposes of computing the angle,
@@ -194,11 +152,26 @@ bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
 	// Cosine of the angle between the camera direction
 	// and the block direction (camera_dir is an unit vector)
 	f32 cosangle = dforward / blockpos_adj.getLength();
-	
+
 	// If block is not in the field of view, skip it
-	if(cosangle < cos(camera_fov / 2))
+	// HOTFIX: use sligthly increased angle (+10%) to fix too agressive
+	// culling. Somebody have to find out whats wrong with the math here.
+	// Previous value: camera_fov / 2
+	if(cosangle < cos(camera_fov * 0.55))
 		return false;
 
 	return true;
 }
 
+s16 adjustDist(s16 dist, float zoom_fov)
+{
+	// 1.775 ~= 72 * PI / 180 * 1.4, the default on the client
+	const float default_fov = 1.775f;
+	// heuristic cut-off for zooming
+	if (zoom_fov > default_fov / 2.0f)
+		return dist;
+
+	// new_dist = dist * ((1 - cos(FOV / 2)) / (1-cos(zoomFOV /2))) ^ (1/3)
+	return round(dist * cbrt((1.0f - std::cos(default_fov / 2.0f)) /
+		(1.0f - std::cos(zoom_fov / 2.0f))));
+}