X-Git-Url: http://bicyclesonthemoon.info/git-projects/?a=blobdiff_plain;f=core.c;h=0a3d1c41da19d3670bb4bd1a238113063a1f8384;hb=c9c9c6198f49a3a9159ed2f90753be548f42ecac;hp=6e2928aebebc9dec8afe88e2d4a7b8cf9b713bcc;hpb=8c85da0b525fbdc75e486d1a1c756c77086cb657;p=ott%2Fenhance

diff --git a/core.c b/core.c
index 6e2928a..0a3d1c4 100644
--- a/core.c
+++ b/core.c
@@ -1,7 +1,7 @@
 /*
 core.c
 The tool with multiple enhancements and manipulations of pictures
-26.11.2022
+03.12.2022
 
 Copyright (C) 2014, 2015, 2022  Balthasar Szczepański
 
@@ -1561,6 +1561,67 @@ int palette_mix_index (ILuint n, struct PixelInfo *p, void *data)
 	return 0;
 }
 
+ILuint tsqrt(ILuint s)
+{
+	switch(s)
+	{
+	case 256:
+		return 16;
+	case 225:
+		return 15;
+	case 196:
+		return 14;
+	case 169:
+		return 13;
+	case 144:
+		return 12;
+	case 121:
+		return 11;
+	case 100:
+		return 10;
+	case 81:
+		return 9;
+	case 64:
+		return 8;
+	case 49:
+		return 7;
+	case 36:
+		return 6;
+	case 25:
+		return 5;
+	case 16:
+		return 4;
+	case 9:
+		return 3;
+	case 4:
+		return 2;
+	case 1:
+		return 1;
+	default: // not a square - please fail
+		return 0;
+	}
+}
+
+//unsigned short isqrt(unsigned s)
+//{
+//      unsigned short r;
+//      unsigned short b=0x0040;
+//      
+//      while(b>s)
+//	      b>>=2;
+//      while(b)
+//      {
+//	      if(s>=r+b)
+//	      {
+//		      s-=r+b;
+//		      r=(r>>1)+b;
+//	      }
+//	      else
+//		      r>>1;
+//	      b>>2;
+//      }
+//      return r;
+//}
 
 
 // int action(