Initial commit: base-road-network copy

src/simulator.odin

@@ -0,0 +1,192 @@
+package main
+
+import rl "vendor:raylib"
+
+import "common"
+import "core:fmt"
+import inf "infrastructure"
+
+Simulator :: struct {
+	// Stores all nodes
+	nodes: [dynamic]inf.Node,
+	// Stores all roads
+	roads: [dynamic]inf.Road,
+	// Tracks the temporary node location
+	temp_node: Maybe(u32),
+	// Tracks the selected road
+	highlighted_road: Maybe(u32),
+	// Tracks whether the user wishes to see node's snapping radius
+	show_details: bool,
+	// Tracks whether after placing a road new one will start being placed
+	auto_continue: bool,
+	// Tracks whether the delete mode is activated
+	delete_mode: bool,
+}
+
+// Destructor
+deinit :: proc(self: ^Simulator) {
+	self.temp_node = nil
+	self.highlighted_road = nil
+	
+	delete(self.roads)
+	
+	for &node in self.nodes {
+		inf.node_deinit(&node)
+	}
+	delete(self.nodes)
+}
+
+// Functionality that runs every tick regardless of input
+update :: proc(self: ^Simulator, pos: rl.Vector2) {
+	update_highlighted_road(self, pos)
+}
+
+// Implementation of road building after a click has been registered
+@private
+create_road :: proc(self: ^Simulator, pos: rl.Vector2) {
+	// BUILD
+	cur_node_index := get_node_or_new(self, pos)
+	
+	if temp, ok := self.temp_node.?; ok {
+		// If both values are identical this means the user has to create a new road using the same nodes
+		if cur_node_index == temp do return
+		data := get_intersecting_roads(self, temp, cur_node_index)
+		split_roads_by_points(self, data, temp, cur_node_index)
+		
+		self.temp_node = self.auto_continue ? cur_node_index : nil
+		return
+	}
+	
+	self.temp_node = cur_node_index
+}
+
+// Returns data about roads that intersect the given 2 nodes (points)
+@(private="file")
+get_intersecting_roads :: proc(self: ^Simulator, start: u32, end: u32) -> []common.Intersection_Data {
+	intersections: [dynamic]common.Intersection_Data
+	collision_point: rl.Vector2
+	
+	outer: for road, index in self.roads {
+		road_start_node := road.nodes[0]
+		road_end_node := road.nodes[1]
+		
+		if !rl.CheckCollisionLines(self.nodes[start].pos, self.nodes[end].pos, self.nodes[road_start_node].pos, self.nodes[road_end_node].pos, &collision_point) do continue
+		
+		// Save the collision info
+		data := common.Intersection_Data {
+			road = u32(index),
+			point = collision_point
+		}
+		
+		node := inf.node_init(data.point)
+		// Here we check if the intersection points that were recorded before, are already within snapping radius of our current intersected point
+		for collision in intersections {
+			if (inf.node_within_snapping_radius(&node, collision.point)) do continue outer
+		}
+		
+		// Here we check if our new intersected point node is too close to already established nodes
+		if _, ok := get_node_index_if_exists(self, data.point); ok do continue
+		
+		append(&intersections, data)
+	}
+	
+	return intersections[:]
+}
+
+// Given intersection data, the function splits all existing roads and adds new nodes on intersections
+@(private="file")
+split_roads_by_points :: proc(self: ^Simulator, intersections: []common.Intersection_Data, start: u32, end: u32) {
+	if len(intersections) == 0 {
+		add_road(self, start, end)
+		return
+	}
+	
+	first_intersection_node := get_node_or_new(self, intersections[0].point)
+	add_road(self, start, first_intersection_node)
+	
+	for i in 0..<len(intersections) {
+		intersection := intersections[i]
+		// The node created at the point of intersection
+		new_node := get_node_or_new(self, intersection.point)
+		
+		// Pointer to the node that borders the road that was intersected
+		// This node and the new node will become nodes for the new road being created
+		road_old_node := self.roads[intersection.road].nodes[1]
+		
+		// The old road that was intersected now borders the new node
+		// and the old node is removed from the road's end node reference,
+		// as is the end node's road reference
+		ok := update_node_reference(self, intersection.road, road_old_node, new_node)
+		if !ok do fmt.panicf("Failed to update the node reference to the Road ID=%d, because I couldn't find old reference ID=%d\n", 
+			intersection.road, road_old_node)
+		
+		// This adds the road (to the road manager) and also references the road at both nodes (pointers)
+		add_road(self, new_node, road_old_node)
+		
+		if (i == len(intersections) - 1) do continue
+		
+		node_start := get_node_or_new(self, intersection.point)
+		node_end := get_node_or_new(self, intersections[i + 1].point)
+		
+		add_road(self, node_start, node_end)
+	}
+	
+	last_intersection_road := intersections[len(intersections) - 1]
+	last_intersection_node := get_node_or_new(self, last_intersection_road.point)
+	add_road(self, last_intersection_node, end)
+}
+
+// Adds a new road into roads array, start and end are indexes of existing nodes
+@(private="file")
+add_road :: proc(self: ^Simulator, start: u32, end: u32) {
+	road := inf.road_init(start, end)
+	append(&self.roads, road)
+	
+	road_index := u32(len(self.roads) - 1)
+	append(&self.nodes[start].roads, road_index)
+	append(&self.nodes[end].roads, road_index)
+}
+
+// Deletes the road which index was sent in, alongside deleting references of said road and removal of nodes if that road was their only connection
+@private
+delete_road :: proc(self: ^Simulator, road_to_delete: u32) {
+	// First we need to unreference this road from surrounding nodes and then delete those nodes IF this was the last road connection
+	road := self.roads[road_to_delete]
+	// Pointers to the nodes bordering the road we wish to delete
+	start_node := &self.nodes[road.nodes[0]]
+	end_node := &self.nodes[road.nodes[1]]
+	
+	// We unreference the road from the nodes bordering the road
+	start_unref := inf.node_unreference_road(start_node, road_to_delete)
+	end_unref := inf.node_unreference_road(end_node, road_to_delete)
+	if !start_unref || !end_unref do fmt.panicf("Failed to unreference one (or both) of the nodes of the Road ID=%d\n", road_to_delete)
+	
+	// Now we delete the road
+	delete_entity(self, road_to_delete, .Road)
+	
+	// After the remove we have to replace references
+	if len(start_node.roads) == 0 {
+		// If the id of the next node gets swapped we must update it accordingly
+		if result, ok := delete_entity(self, road.nodes[0], .Node); ok && result[0] == road.nodes[1] {
+			road.nodes[1] = result[1]
+		}
+	}
+	
+	if len(end_node.roads) == 0 do delete_entity(self, road.nodes[1], .Node)
+}
+
+// Keeps track of the selected/highlighted road
+@(private="file")
+update_highlighted_road :: proc(self: ^Simulator, pos: rl.Vector2) {
+	for road, index in self.roads {
+		start_node := self.nodes[road.nodes[0]]
+		end_node := self.nodes[road.nodes[1]]
+		
+		if !rl.CheckCollisionPointLine(pos, start_node.pos, end_node.pos, common.ROAD_SIZE) do continue
+		
+		self.highlighted_road = u32(index)
+		return
+	}
+	
+	self.highlighted_road = nil
+}