From 620d3b56e05ccb66128db432ba3a2ec7bb7a61b3 Mon Sep 17 00:00:00 2001
From: Marto <marto@marto.si>
Date: Mon, 27 Apr 2026 09:42:50 +0200
Subject: [PATCH] Pathfinding initial implementation [2 errors]

---
 src/common/utils.odin           | 15 ++++++++++++
 src/infrastructure_helpers.odin | 15 ++++++++++++
 src/pathfinding.odin            | 43 +++++++++++++++++++++++++++++++++
 src/system/pathfinding.odin     | 11 ---------
 src/vehicles/car.odin           | 23 +++++++++---------
 5 files changed, 84 insertions(+), 23 deletions(-)
 create mode 100644 src/common/utils.odin
 create mode 100644 src/pathfinding.odin
 delete mode 100644 src/system/pathfinding.odin

diff --git a/src/common/utils.odin b/src/common/utils.odin
new file mode 100644
index 0000000..885b36b
--- /dev/null
+++ b/src/common/utils.odin
@@ -0,0 +1,15 @@
+package common
+
+// Generic contains function for an (dynamic) array
+list_contains :: proc(list: []$T, element: T) -> bool {
+	for el in list do if el == element do return true
+	
+	return false
+}
+
+// Inserts element into the list after asserting that element is not already within
+insert_if_not_exists :: proc(list: ^[]$T, element: T) {
+	if list_contains(list, element) do return
+	
+	append(list, element)
+}
\ No newline at end of file
diff --git a/src/infrastructure_helpers.odin b/src/infrastructure_helpers.odin
index df974c2..b8ce09b 100644
--- a/src/infrastructure_helpers.odin
+++ b/src/infrastructure_helpers.odin
@@ -1,6 +1,7 @@
 package main
 
 import rl "vendor:raylib"
+import "core:math/rand"
 
 import "common"
 import inf "infrastructure"
@@ -99,5 +100,19 @@ delete_entity :: proc(self: ^Simulator, entity_index: u32, type: common.Entity)
 
 // Returns a random node that has no cars on it
 get_free_node :: proc(self: ^Simulator) -> u32 {
+	car_occupied_nodes: [dynamic]u32
 	
+	for car in self.cars {
+		node, ok := car.node_pos.?
+		if !ok do continue
+		
+		if common.list_contains(car_occupied_nodes[:], node) do continue
+		append(&car_occupied_nodes, node)
+	}
+	
+	for {
+		node := rand.uint32_max(u32(len(self.nodes)))
+		
+		if !common.list_contains(car_occupied_nodes[:], node) do return node
+	}
 }
\ No newline at end of file
diff --git a/src/pathfinding.odin b/src/pathfinding.odin
new file mode 100644
index 0000000..5235044
--- /dev/null
+++ b/src/pathfinding.odin
@@ -0,0 +1,43 @@
+package main
+
+import "common"
+import inf "infrastructure"
+
+// Returns path to destination node => road => node
+get_path_to_destination :: proc(self: ^Simulator, source: u32, destination: u32) -> []u32 {
+	source_node := self.nodes[source]
+	destination_node := self.nodes[destination]
+	
+	return nil
+}
+
+// Returns if path is reachable from node => destination
+get_destination_reachable :: proc(self: ^Simulator, node_to_search: u32, destination: u32, nodes_to_ignore: ^[]u32) -> bool {
+	if !self.nodes[node_to_search].enabled || common.list_contains(nodes_to_ignore[:], node_to_search) do return false
+	append(nodes_to_ignore, node_to_search)
+	
+	if node_to_search == destination do return true
+	for node in get_neighbouring_nodes(self, node_to_search) {
+		if get_destination_reachable(self, node, destination, nodes_to_ignore) do return true
+	}
+	
+	return false
+}
+
+@(private="file")
+get_neighbouring_nodes :: proc(self: ^Simulator, node_index: u32) -> []u32 {
+	node := self.nodes[node_index]
+	neighbour_nodes := make([dynamic]u32, 0, len(node.roads))
+	
+	for road_index in node.roads {
+		road := self.roads[road_index]
+		
+		// We pick the node that is not the original node with which we reached the node
+		// But rather the other node, on the end
+		next_node := road.nodes[0] == node_index ? road.nodes[1] : road.nodes[0]
+		
+		if !common.list_contains(neighbour_nodes[:], next_node) do append(&neighbour_nodes, next_node)
+	}
+	
+	return neighbour_nodes[:]
+}
\ No newline at end of file
diff --git a/src/system/pathfinding.odin b/src/system/pathfinding.odin
deleted file mode 100644
index c43bc05..0000000
--- a/src/system/pathfinding.odin
+++ /dev/null
@@ -1,11 +0,0 @@
-package system
-
-import inf "../infrastructure"
-
-get_path_to_destination :: proc(source: u32, destination: u32, nodes: []inf.Node) {
-	source_node := nodes[source]
-	destination_node := nodes[destination]
-	
-	
-}
-
diff --git a/src/vehicles/car.odin b/src/vehicles/car.odin
index 45c295e..330f797 100644
--- a/src/vehicles/car.odin
+++ b/src/vehicles/car.odin
@@ -19,32 +19,31 @@ Car :: struct {
 	// Car's destination node
 	destination: Maybe(u32),
 	// Tracks on which node car has been last
-	node_pos: u32,
+	// 
+	// if null car is not on node
+	node_pos: Maybe(u32), 
+	// if null car is not on road
 	road_pos: Maybe(u32),
+	// tracks absolute pos
 	actual_pos: rl.Vector2,
 }
 
 // Constructor
-car_init :: proc(nodes: []inf.Node) -> Car {
-	rand_origin := rand.uint32_max(nodes_len)
-	
+car_init :: proc(node: u32, nodes: []inf.Node) -> Car {	
 	return {
 		fuel_level = common.FUEL_MAX,
 		max_speed = common.CAR_MAX_SPEED,
-		origin = rand_origin,
-		node_pos = rand_origin,
-		actual_pos = 
+		origin = node,
+		node_pos = node,
+		actual_pos = nodes[node].pos
 	}
 }
 
 // Sets a (valid) route for the car
 // 
-// Does NOT guarantee the route is reachable (TODO?)
+// Does NOT guarantee the route is reachable (TODO!)
 car_set_route :: proc(self: ^Car, nodes_len: u32) {
-	for self.origin == self.destination {
-		self.destination = rand.uint32_max(nodes_len)
-	}
-	
+	for self.origin == self.destination do self.destination = rand.uint32_max(nodes_len)
 }
 
 // Updates (origin and destination) node reference