From f79863d3c1468dd6bfaa87088f53f9c9d0ba5ef5 Mon Sep 17 00:00:00 2001
From: Marco Hladik <marco@icculus.org>
Date: Thu, 23 Apr 2020 04:33:11 +0200
Subject: [PATCH] Counter-Strike: WEAPON_FLASHBANG now does some fancy
 calculation for flashing players.

---
 src/shared/cstrike/fx_flashbang.c | 44 +++++++++++++++++++++++++++----
 src/shared/cstrike/w_flashbang.c  |  1 +
 src/shared/valve/fx_blood.c       | 14 +++++-----
 3 files changed, 46 insertions(+), 13 deletions(-)

diff --git a/src/shared/cstrike/fx_flashbang.c b/src/shared/cstrike/fx_flashbang.c
index 42e134f5..f747286d 100644
--- a/src/shared/cstrike/fx_flashbang.c
+++ b/src/shared/cstrike/fx_flashbang.c
@@ -16,11 +16,45 @@
 
 #ifdef SERVER
 void
-FX_Flashbang(entity eTarget)
+FX_Flashbang(vector org)
 {
-	WriteByte(MSG_MULTICAST, SVC_CGAMEPACKET);
-	WriteByte(MSG_MULTICAST, EV_FLASH);
-	msg_entity = eTarget;
-	multicast([0,0,0], MULTICAST_ONE);
+	for (entity e = world; (e = find(e, ::classname, "player"));) {
+		float fov_dot;
+		vector val;
+		float blindness;
+		float fade;
+
+		/* wall check */
+		traceline(e.origin + e.view_ofs, org, FALSE, e);
+		if (trace_fraction < 1.0f)
+			continue;
+
+		/* calculate the fov in dotproduct form */
+		makevectors(e.v_angle);
+		val = normalize(org - (e.origin + e.view_ofs));
+		fov_dot = val * v_forward;
+
+		/* it's behind us */
+		if (fov_dot < 0) {
+			blindness = 0.1;
+			fade = 1.0f;
+		} else {
+			blindness = 2 * fov_dot;
+			fade = 4 * fov_dot;
+		}
+
+		/* send the blinding env_fade event */
+		WriteByte(MSG_MULTICAST, SVC_CGAMEPACKET);
+		WriteByte(MSG_MULTICAST, EV_FADE);
+		WriteFloat(MSG_MULTICAST, 1.0f);
+		WriteFloat(MSG_MULTICAST, 1.0f);
+		WriteFloat(MSG_MULTICAST, 1.0f);
+		WriteFloat(MSG_MULTICAST, 1.0f);
+		WriteFloat(MSG_MULTICAST, blindness);
+		WriteFloat(MSG_MULTICAST, fade);
+		WriteByte(MSG_MULTICAST, EVF_FADEDROM);
+		msg_entity = e;
+		multicast('0 0 0', MULTICAST_ONE_R);
+	}
 }
 #endif 
diff --git a/src/shared/cstrike/w_flashbang.c b/src/shared/cstrike/w_flashbang.c
index 1a91953d..16b2db6a 100644
--- a/src/shared/cstrike/w_flashbang.c
+++ b/src/shared/cstrike/w_flashbang.c
@@ -101,6 +101,7 @@ void w_flashbang_throw(void)
 {
 	static void flashbang_explode(void)
 	{
+		FX_Flashbang(self.origin);
 		Sound_Play(self, CHAN_BODY, "weapon_flashbang.explode");
 		remove(self);
 	}
diff --git a/src/shared/valve/fx_blood.c b/src/shared/valve/fx_blood.c
index 92fd9e5f..446a01c6 100644
--- a/src/shared/valve/fx_blood.c
+++ b/src/shared/valve/fx_blood.c
@@ -32,11 +32,11 @@ FX_Blood(vector pos, vector color)
 #ifdef SERVER
 	WriteByte(MSG_MULTICAST, SVC_CGAMEPACKET);
 	WriteByte(MSG_MULTICAST, EV_BLOOD);
-	WriteCoord(MSG_MULTICAST, pos[0]); 
-	WriteCoord(MSG_MULTICAST, pos[1]); 
+	WriteCoord(MSG_MULTICAST, pos[0]);
+	WriteCoord(MSG_MULTICAST, pos[1]);
 	WriteCoord(MSG_MULTICAST, pos[2]);
-	WriteByte(MSG_MULTICAST, color[0] * 255); 
-	WriteByte(MSG_MULTICAST, color[1] * 255); 
+	WriteByte(MSG_MULTICAST, color[0] * 255);
+	WriteByte(MSG_MULTICAST, color[1] * 255);
 	WriteByte(MSG_MULTICAST, color[2] * 255);
 	msg_entity = self;
 	multicast(pos, MULTICAST_PVS);
@@ -51,8 +51,6 @@ FX_Blood(vector pos, vector color)
 	setorigin(eBlood, pos);
 	setmodel(eBlood, "sprites/bloodspray.spr");
 
-	//eExplosion.think = FX_Explosion_Animate;
-	//eBlood.effects = EF_ADDITIVE;
 	eBlood.drawmask = MASK_ENGINE;
 	eBlood.maxframe = modelframecount(eBlood.modelindex);
 	eBlood.loops = 0;
@@ -60,7 +58,7 @@ FX_Blood(vector pos, vector color)
 	eBlood.colormod = color;
 	eBlood.framerate = 20;
 	eBlood.nextthink = time + 0.05f;
-	
+
 	for (int i = 0; i < 3; i++) {
 		env_sprite ePart = spawn(env_sprite);
 		setorigin(ePart, pos);
@@ -80,4 +78,4 @@ FX_Blood(vector pos, vector color)
 		setsize(ePart, [0,0,0], [0,0,0]);
 	}
 #endif
-} 
+}