From 9b5a2f1247208cb620a30de73ffce0a1e747f601 Mon Sep 17 00:00:00 2001
From: Elronnd <elronnd@elronnd.net>
Date: Sun, 29 Jul 2018 06:31:37 -0700
Subject: [PATCH] add *much nicer* brightness normalization, thanks to
 /u/dustyloops and /u/aotdev

---
 src/light.d |  5 +++--
 src/myfov.d | 10 +++++++++-
 src/util.d  |  5 ++++-
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/light.d b/src/light.d
index 67af244..e6a49ea 100644
--- a/src/light.d
+++ b/src/light.d
@@ -48,9 +48,10 @@ void do_colour(ref Map map, list!Being mons) {
 				continue;
 			}
 
-			float f = base[y][x].value / maxf;
+			float f1 = pow(base[y][x].value, .8) / 4.3;
+			float f = f1 / (f1+1); //smaxf;
 //			map[y, x].bgcolour = RGBColour(pow(f/2, 1.5), pow(f/1.4, 3), pow(f/16, 2));
-			map[y, x].bgcolour = RGBColour(f, f, f);
+			map[y, x].bgcolour = RGBColour(f*1.1, f, f/9);
 			//writefln("Set bg to %s", map[y, x].bgcolour);
 		}
 	}
diff --git a/src/myfov.d b/src/myfov.d
index 1e053f7..c5214f3 100644
--- a/src/myfov.d
+++ b/src/myfov.d
@@ -62,7 +62,15 @@ private void compute(const ref Map map, ref Lightmap lightmap, int octant, Point
 			default: break;
 		}
 		lightmap[ny, nx].visible = true;
-		lightmap[ny, nx].visibility = 1 - dist(nx, ny, origin.x, origin.y) / sqrt(rangeLimit);
+		float vis_sq = dist_sq(nx, ny, origin.x, origin.y);
+		float f3 = sqrt(rangeLimit) / (vis_sq);
+		//float f3 = f1 / (f1 + 5);
+		/*
+		float f1 = 1. / (1. + vis_sq/40.);
+		float f2 = f1 - 1. / (1. + rangeLimit);
+		float f3 = f2 / (1. - 1. / (1. + rangeLimit));
+		*/
+		lightmap[ny, nx].visibility = f3; //1 - dist(nx, ny, origin.x, origin.y) / sqrt(rangeLimit);
 		// this makes conentric squares.  Probably faster
 		//lightmap[ny, nx].visibility = 1 - cast(float)max(abs(nx - origin.x), abs(ny - origin.y)) / 32.;
 	}
diff --git a/src/util.d b/src/util.d
index 84aead0..f7eb432 100644
--- a/src/util.d
+++ b/src/util.d
@@ -101,9 +101,12 @@ alias get256colour = memoize!((RGBColour colour) {
 });
 
 float dist(int x1, int y1, int x2, int y2) {
+	return sqrt(dist_sq(x1, y1, x2, y2));
+}
+int dist_sq(int x1, int y1, int x2, int y2) {
 	int px = x1 - x2;
 	int py = y1 - y2;
-	return sqrt(cast(float)px * px + py * py);
+	return px * px + py * py;
 }
 
 
-- 
2.11.4.GIT