From: Rudolf Polzer <divverent@alientrap.org>
Date: Sat, 28 Aug 2010 09:20:59 +0000 (+0200)
Subject: use Scharr operator instead of Sobel operator for edge detection
X-Git-Tag: xonotic-v0.1.0preview~255
X-Git-Url: http://git.xonotic.org/?p=xonotic%2Fxonotic.git;a=commitdiff_plain;h=443b4bfa9f18f22c56b22537ef856ad1ba617d74

use Scharr operator instead of Sobel operator for edge detection
---

diff --git a/misc/tools/fft-normalmap-to-heightmap.c b/misc/tools/fft-normalmap-to-heightmap.c
index aa4ac7ff..17f9fd89 100644
--- a/misc/tools/fft-normalmap-to-heightmap.c
+++ b/misc/tools/fft-normalmap-to-heightmap.c
@@ -354,11 +354,11 @@ void hmap_to_nmap_local(unsigned char *map, int w, int h, int src_chan, double s
 	int i, j;
 	double *img_reduced = malloc(w*h * sizeof(double));
 	static const double filter[3][3] = { /* filter to derive one component */
-		{ -1, 0, 1 },
-		{ -2, 0, 2 },
-		{ -1, 0, 1 }
+		{  -3, 0,  3 },
+		{ -10, 0, 10 },
+		{  -3, 0,  3 }
 	};
-	static const double filter_mult = 0.125;
+	static const double filter_mult = 0.03125;
 
 	for(y = 0; y < h; ++y)
 	for(x = 0; x < w; ++x)