From: Martin Taibr <taibr.martin@gmail.com>
Date: Mon, 12 Nov 2018 22:27:46 +0000 (+0100)
Subject: comment NaN handling
X-Git-Tag: xonotic-v0.8.5~1258^2~43
X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=c5724c3955aaa0135aebf8875b70a8f91358d582;p=xonotic%2Fxonotic-data.pk3dir.git

comment NaN handling
---

diff --git a/qcsrc/lib/deglobalization.qh b/qcsrc/lib/deglobalization.qh
index 1097035bf..d9417b489 100644
--- a/qcsrc/lib/deglobalization.qh
+++ b/qcsrc/lib/deglobalization.qh
@@ -20,13 +20,20 @@
 #ifdef GAMEQC
 STATIC_INIT(globals) {
 	// set to NaN to more easily detect uninitialized use
-    // TODO when all functions are wrapped and the raw functions are not used anymore,
-    // assert that the global vectors are NaN before calling the raw functions
-    // to make sure nobody (even builtins) is accidentally using them - NaN is the most likely value to expose remaining usages
+	// TODO when all functions are wrapped and the raw functions are not used anymore,
+	// assert that the global vectors are NaN before calling the raw functions
+	// to make sure nobody (even builtins) is accidentally using them - NaN is the most likely value to expose remaining usages
+
+	// TODO make sure `isnan` actually works - potential compiler bug:
+	//LOG_INFOF("%f\n", 0.0/0.0 == 0.0/0.0);
+	//LOG_INFOF("%f\n", 0.0/0.0 != 0.0/0.0);
+	//float x = 0.0/0.0;
+	//LOG_INFOF("%f\n", x == x);
+	//LOG_INFOF("%f\n", x != x);
+
 	v_forward = VEC_NAN;
 	v_right = VEC_NAN;
 	v_up = VEC_NAN;
-	// FIXME check this is actually NaN
 }
 #endif
 
diff --git a/qcsrc/lib/vector.qh b/qcsrc/lib/vector.qh
index eae8d4397..d49322efb 100644
--- a/qcsrc/lib/vector.qh
+++ b/qcsrc/lib/vector.qh
@@ -109,6 +109,11 @@ noref vector _vec3;
 
 #define VEC_NAN vec3(FLOAT_NAN, FLOAT_NAN, FLOAT_NAN);
 
+ERASEABLE
+bool is_all_nans(vector v) {
+	return isnan(v.x) && isnan(v.y) && isnan(v.z);
+}
+
 ERASEABLE
 vector Rotate(vector v, float a)
 {