simple dynamic crosshair

godot/Scenes/Characters/first_person_player.tscn

@@ -24,3 +24,42 @@ transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0.1, 0)
 
 [node name="Steampunk Rifle" parent="Head/Camera" instance=ExtResource("1_i6keg")]
 transform = Transform3D(1, 0, 0, 0, 0.998135, -0.0610485, 0, 0.0610485, 0.998135, 0.19, -0.18, -0.55)
+
+[node name="UserInterface" type="Control" parent="."]
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+mouse_filter = 1
+
+[node name="Crosshair" type="Crosshair" parent="UserInterface"]
+layout_mode = 1
+anchors_preset = 8
+anchor_left = 0.5
+anchor_top = 0.5
+anchor_right = 0.5
+anchor_bottom = 0.5
+offset_left = -20.0
+offset_top = -20.0
+offset_right = 20.0
+offset_bottom = 20.0
+grow_horizontal = 2
+grow_vertical = 2
+
+[node name="Top" type="Line2D" parent="UserInterface/Crosshair"]
+points = PackedVector2Array(0, -5, 0, -15)
+width = 2.0
+
+[node name="Right" type="Line2D" parent="UserInterface/Crosshair"]
+points = PackedVector2Array(5, 0, 15, 0)
+width = 2.0
+
+[node name="Bottom" type="Line2D" parent="UserInterface/Crosshair"]
+points = PackedVector2Array(0, 5, 0, 15)
+width = 2.0
+
+[node name="Left" type="Line2D" parent="UserInterface/Crosshair"]
+points = PackedVector2Array(-5, 0, -15, 0)
+width = 2.0

src/BoneCollisionShape.cpp

@@ -24,7 +24,10 @@ BoneCollisionShape::BoneCollisionShape() {}
 
 BoneCollisionShape::~BoneCollisionShape() {}
 
-void BoneCollisionShape::_ready() {}
+void BoneCollisionShape::_ready() {
+    m_Crosshair = Object::cast_to<Crosshair>(get_parent()->get_parent()->get_parent()->get_parent()->get_parent()->get_parent()->get_parent()->find_child("Crosshair"));
+    DEV_ASSERT(m_Crosshair);
+}
 
 void BoneCollisionShape::set_head_damage(int a_D) {
     m_HeadDamage = a_D;
@@ -44,11 +47,13 @@ int BoneCollisionShape::get_body_damage() const {
 
 void BoneCollisionShape::headshot_hit() {
     ERR_PRINT("zombie headshot hit");
+    m_Crosshair->set_dot_color(Color(1,0,0,1));
     emit_signal("a_ZombieHeadShotHit", m_HeadDamage);
 }
 
 void BoneCollisionShape::bodyshot_hit() {
     ERR_PRINT("zombie body hit");
+    m_Crosshair->set_dot_color(Color(0,0,1,1));
     emit_signal("a_ZombieBodyShotHit", m_BodyDamage);
 }
 

src/BoneCollisionShape.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "Crosshair.h"
 #include <godot_cpp/classes/area3d.hpp>
 
 namespace blitz {
@@ -25,6 +26,7 @@ class BoneCollisionShape : public godot::Area3D {
 	int get_head_damage() const;
 	void set_body_damage(int d);
 	int get_body_damage() const;
+	Crosshair* m_Crosshair;
 };
 
 }  // namespace blitz

src/Bullet.cpp

@@ -25,6 +25,8 @@ void Bullet::_ready() {
 	m_Timer = memnew(Timer);
 	add_child(m_Timer);
 	m_Timer->connect("timeout", callable_mp(this, &Bullet::_on_timer_timeout));
+	m_Crosshair = Object::cast_to<Crosshair>(get_parent()->find_child("Crosshair"));
+	DEV_ASSERT(m_Crosshair);
 }
 
 void Bullet::_physics_process(float a_Delta) {
@@ -53,6 +55,7 @@ void Bullet::_physics_process(float a_Delta) {
 }
 
 void Bullet::_on_timer_timeout() {
+	m_Crosshair->set_dot_color(Color(1, 1, 1, 1));
 	queue_free();
 }
 

src/Bullet.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "Crosshair.h"
 #include <godot_cpp/classes/gpu_particles3d.hpp>
 #include <godot_cpp/classes/mesh_instance3d.hpp>
 #include <godot_cpp/classes/node3d.hpp>
@@ -24,6 +25,7 @@ class Bullet : public godot::Node3D {
 	godot::RayCast3D* m_Ray;
 	godot::MeshInstance3D* m_Mesh;
 	godot::Timer* m_Timer;
+	Crosshair* m_Crosshair;
 
 	void _on_timer_timeout();
 };

src/Crosshair.cpp

@@ -0,0 +1,59 @@
+#include "Crosshair.h"
+
+using namespace godot;
+
+namespace blitz {
+void Crosshair::_bind_methods() {}
+
+Crosshair::Crosshair() :
+	m_DotRadius(1.0f),
+	m_DotColor(Color(1, 1, 1, 1)),
+	m_CrosshairSpeed(0.25f),
+	m_CrosshairDistance(2.0f),
+	m_Origin(Vector3(0, 0, 0)),
+	m_Pos(Vector2(0, 0)) {}
+Crosshair::~Crosshair() {}
+
+void Crosshair::_ready() {
+	m_Player = Object::cast_to<FirstPersonPlayer>(get_parent()->get_parent()->get_parent()->find_child("FirstPersonPlayer"));
+	DEV_ASSERT(m_Player);
+	m_CrosshairLines = {Object::cast_to<Line2D>(find_child("Top")), Object::cast_to<Line2D>(find_child("Right")),
+		Object::cast_to<Line2D>(find_child("Bottom")), Object::cast_to<Line2D>(find_child("Left"))};
+	for (size_t i = 0; i < m_CrosshairLines.size(); i++) {
+		DEV_ASSERT(m_CrosshairLines[i]);
+	}
+	queue_redraw();
+}
+
+void Crosshair::_process(float a_Delta) {
+	adjust_crosshair_lines();
+}
+
+void Crosshair::_draw() {
+	draw_circle(Vector2(0, 0), m_DotRadius, m_DotColor);
+}
+
+void Crosshair::adjust_crosshair_lines() {
+	Vector3 vel = m_Player->get_real_velocity();
+
+	float speed = m_Origin.distance_to(vel);
+
+	m_CrosshairLines[0]->set_position(
+		m_CrosshairLines[0]->get_position().lerp(m_Pos + Vector2(0, -speed * m_CrosshairDistance), m_CrosshairSpeed));
+
+	m_CrosshairLines[1]->set_position(
+		m_CrosshairLines[1]->get_position().lerp(m_Pos + Vector2(speed * m_CrosshairDistance, 0), m_CrosshairSpeed));
+
+	m_CrosshairLines[2]->set_position(
+		m_CrosshairLines[2]->get_position().lerp(m_Pos + Vector2(0, speed * m_CrosshairDistance), m_CrosshairSpeed));
+
+	m_CrosshairLines[3]->set_position(
+		m_CrosshairLines[3]->get_position().lerp(m_Pos + Vector2(-speed * m_CrosshairDistance, 0), m_CrosshairSpeed));
+}
+
+void Crosshair::set_dot_color(Color a_Color) {
+	m_DotColor = a_Color;
+	queue_redraw();
+}
+
+}  // namespace blitz

src/Crosshair.h

@@ -0,0 +1,35 @@
+#pragma once
+
+#include "FirstPersonPlayer.h"
+#include <godot_cpp/classes/center_container.hpp>
+#include <godot_cpp/classes/line2d.hpp>
+
+namespace blitz {
+class Crosshair : public godot::CenterContainer {
+	GDCLASS(Crosshair, godot::CenterContainer)
+  protected:
+	static void _bind_methods();
+
+  public:
+	Crosshair();
+	~Crosshair();
+
+	void _ready();
+	void _process(float delta);
+	void _draw();
+	void set_dot_color(godot::Color col);
+
+  private:
+	godot::Color m_DotColor;
+	float m_DotRadius;
+	std::array<godot::Line2D*, 4> m_CrosshairLines;
+	FirstPersonPlayer* m_Player;
+	float m_CrosshairSpeed;
+	float m_CrosshairDistance;
+	godot::Vector3 m_Origin;
+	godot::Vector2 m_Pos;
+
+	void adjust_crosshair_lines();
+};
+
+}  // namespace blitz

src/register_types.cpp

@@ -7,6 +7,7 @@
 #include "SpringArmPivot.h"
 #include "World.h"
 #include "Zombie.h"
+#include  "Crosshair.h"
 
 #include <gdextension_interface.h>
 #include <godot_cpp/core/defs.hpp>
@@ -26,6 +27,7 @@ void initialize_example_module(ModuleInitializationLevel p_level) {
 	ClassDB::register_class<blitz::Zombie>();
 	ClassDB::register_class<blitz::BoneCollisionShape>();
 	ClassDB::register_class<blitz::World>();
+	ClassDB::register_class<blitz::Crosshair>();
 }
 
 void uninitialize_example_module(ModuleInitializationLevel p_level) {