diff --git a/source/games/blood/src/aitchern.cpp b/source/games/blood/src/aitchern.cpp
index 07154b05f..1c056b506 100644
--- a/source/games/blood/src/aitchern.cpp
+++ b/source/games/blood/src/aitchern.cpp
@@ -228,20 +228,22 @@ static void sub_725A4(DBloodActor* actor)
 			auto ppos = pPlayer->actor->spr.pos;
 			auto dvect = ppos.XY() - actor->spr.pos;
 			auto pSector = pPlayer->actor->sector();
-			int nDist = approxDist(dvect);
-			if (nDist > pDudeInfo->seeDist && nDist > pDudeInfo->hearDist)
+			DAngle nAngle = VecToAngle(dvect);
+			double nDist = dvect.Length();
+
+			if (nDist > pDudeInfo->SeeDist() && nDist > pDudeInfo->Heardist())
 				continue;
 			double height = (pDudeInfo->eyeHeight * actor->spr.yrepeat) * REPEAT_SCALE;
 			if (cansee(ppos, pSector, actor->spr.pos.plusZ(-height), actor->sector()))
 				continue;
-			int nDeltaAngle = getincangle(actor->int_ang(), getangle(dvect));
-			if (nDist < pDudeInfo->seeDist && abs(nDeltaAngle) <= pDudeInfo->periphery)
+			DAngle nDeltaAngle = absangle(actor->spr.angle, nAngle);
+			if (nDist < pDudeInfo->SeeDist() && abs(nDeltaAngle) <= pDudeInfo->Periphery())
 			{
 				pDudeExtraE->thinkTime = 0;
 				aiSetTarget(actor, pPlayer->actor);
 				aiActivateDude(actor);
 			}
-			else if (nDist < pDudeInfo->hearDist)
+			else if (nDist < pDudeInfo->Heardist())
 			{
 				pDudeExtraE->thinkTime = 0;
 				aiSetTarget(actor, ppos);