From e0d0e6393d65f08db09e2f0422946681eb6a4591 Mon Sep 17 00:00:00 2001
From: Ivan Avdeev <me@w23.ru>
Date: Sun, 24 Oct 2021 13:17:13 -0700
Subject: [PATCH] rtx: add target support for spotlights, fix #128

---
 ref_vk/vk_mapents.c | 67 ++++++++++++++++++++++++++++++++++++++++++++-
 ref_vk/vk_mapents.h | 14 ++++++++++
 2 files changed, 80 insertions(+), 1 deletion(-)

diff --git a/ref_vk/vk_mapents.c b/ref_vk/vk_mapents.c
index 6de92d16..efeacbac 100644
--- a/ref_vk/vk_mapents.c
+++ b/ref_vk/vk_mapents.c
@@ -46,6 +46,15 @@ static unsigned parseEntPropInt(const char* value, int *out, unsigned bit) {
 	return (1 == sscanf(value, "%d", out)) ? bit : 0;
 }
 
+static unsigned parseEntPropString(const char* value, string *out, unsigned bit) {
+	const int len = Q_strlen(value);
+	if (len >= sizeof(string))
+		gEngine.Con_Printf(S_ERROR, "Map entity value '%s' is too long, max length is %d\n",
+			value, sizeof(string));
+	Q_strncpy(*out, value, sizeof(*out));
+	return bit;
+}
+
 static unsigned parseEntPropVec3(const char* value, vec3_t *out, unsigned bit) {
 	return (3 == sscanf(value, "%f %f %f", &(*out)[0], &(*out)[1], &(*out)[2])) ? bit : 0;
 }
@@ -175,7 +184,8 @@ static void addLightEntity( const entity_props_t *props, unsigned have_fields )
 			break;
 	}
 
-	// TODO target entity support
+	if (have_fields & Field_target)
+		Q_strcpy(le->target_entity, props->target);
 
 	if ((have_fields & expected_fields) != expected_fields) {
 		gEngine.Con_Printf(S_ERROR "Missing some fields for light entity\n");
@@ -208,6 +218,33 @@ static void addLightEntity( const entity_props_t *props, unsigned have_fields )
 	g_map_entities.num_lights++;
 }
 
+static void addTargetEntity( const entity_props_t *props ) {
+	xvk_mapent_target_t *target = g_map_entities.targets + g_map_entities.num_targets;
+
+	gEngine.Con_Reportf("Adding target entity %s at (%f, %f, %f)\n",
+		props->targetname, props->origin[0], props->origin[1], props->origin[2]);
+
+	if (g_map_entities.num_targets == MAX_MAPENT_TARGETS) {
+		gEngine.Con_Printf(S_ERROR "Too many map target entities\n");
+		return;
+	}
+
+	Q_strcpy(target->targetname, props->targetname);
+	VectorCopy(props->origin, target->origin);
+
+	++g_map_entities.num_targets;
+}
+
+const xvk_mapent_target_t *findTargetByName(const char *name) {
+	for (int i = 0; i < g_map_entities.num_targets; ++i) {
+		const xvk_mapent_target_t *target = g_map_entities.targets + i;
+		if (Q_strcmp(name, target->targetname) == 0)
+			return target;
+	}
+
+	return NULL;
+}
+
 static void readWorldspawn( const entity_props_t *props ) {
 	Q_strcpy(g_map_entities.wadlist, props->wad);
 }
@@ -220,6 +257,7 @@ void XVK_ParseMapEntities( void ) {
 
 	ASSERT(map);
 
+	g_map_entities.num_targets = 0;
 	g_map_entities.num_lights = 0;
 	g_map_entities.single_environment_index = NoEnvironmentLights;
 
@@ -239,6 +277,9 @@ void XVK_ParseMapEntities( void ) {
 			values = (entity_props_t){0};
 			continue;
 		} else if (key[0] == '}') {
+			const int target_fields = Field_targetname | Field_origin;
+			if ((have_fields & target_fields) == target_fields)
+				addTargetEntity( &values );
 			switch (values.classname) {
 				case Light:
 				case LightSpot:
@@ -276,4 +317,28 @@ void XVK_ParseMapEntities( void ) {
 		}
 #undef CHECK_FIELD
 	}
+
+	// Patch spotlight directions based on target entities
+	for (int i = 0; i < g_map_entities.num_lights; ++i) {
+		vk_light_entity_t *const light = g_map_entities.lights + i;
+		const xvk_mapent_target_t *target;
+
+		if (light->type != LightSpot)
+			continue;
+
+		if (light->target_entity[0] == '\0')
+			continue;
+
+		target = findTargetByName(light->target_entity);
+		if (!target) {
+			gEngine.Con_Printf(S_ERROR "Couldn't find target entity '%s' for spot light %d\n", light->target_entity, i);
+			continue;
+		}
+
+		VectorSubtract(target->origin, light->origin, light->dir);
+		VectorNormalize(light->dir);
+
+		gEngine.Con_Reportf("Light %d patched direction towards '%s': %f %f %f\n", i, target->targetname,
+			light->dir[0], light->dir[1], light->dir[2]);
+	}
 }
diff --git a/ref_vk/vk_mapents.h b/ref_vk/vk_mapents.h
index 3376ad2e..fd5c3189 100644
--- a/ref_vk/vk_mapents.h
+++ b/ref_vk/vk_mapents.h
@@ -15,6 +15,8 @@
 	X(7, float, _cone2, Float) \
 	X(8, int, _sky, Int) \
 	X(9, string, wad, WadList) \
+	X(10, string, targetname, String) \
+	X(11, string, target, String) \
 
 typedef enum {
 	Unknown = 0,
@@ -52,8 +54,17 @@ typedef struct {
 	float stopdot, stopdot2;
 	//char pattern[64];
 	//int dark;
+	
+	string target_entity;
 } vk_light_entity_t;
 
+typedef struct {
+	string targetname;
+	vec3_t origin;
+} xvk_mapent_target_t;
+
+#define MAX_MAPENT_TARGETS 256
+
 typedef struct {
 	int num_lights;
 	vk_light_entity_t lights[256];
@@ -61,6 +72,9 @@ typedef struct {
 	int single_environment_index;
 
 	string wadlist;
+
+	int num_targets;
+	xvk_mapent_target_t targets[MAX_MAPENT_TARGETS];
 } xvk_map_entities_t;
 
 extern xvk_map_entities_t g_map_entities;