From 573eed58ab2f9cd4b76439555d10c3356a7a58df Mon Sep 17 00:00:00 2001
From: Cat Flynn <me@ktyl.dev>
Date: Thu, 8 Dec 2022 21:15:20 +0000
Subject: [PATCH] pulsing cursor #5

---
 half-earth/materials/cursor.tres |  4 ++--
 half-earth/nodes/game.tscn       | 13 +++++++----
 half-earth/scripts/GridCursor.cs | 40 ++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/half-earth/materials/cursor.tres b/half-earth/materials/cursor.tres
index 91a714d..7cc3f5c 100644
--- a/half-earth/materials/cursor.tres
+++ b/half-earth/materials/cursor.tres
@@ -4,6 +4,6 @@
 
 [resource]
 shader = ExtResource( 1 )
-shader_param/lowColor = Color( 1, 0.960784, 0, 1 )
-shader_param/highColor = Color( 0.921569, 0, 1, 1 )
+shader_param/lowColor = Color( 0, 0, 0, 0 )
+shader_param/highColor = Color( 0, 0.976471, 1, 1 )
 shader_param/t = null
diff --git a/half-earth/nodes/game.tscn b/half-earth/nodes/game.tscn
index 5515fad..abfc88c 100644
--- a/half-earth/nodes/game.tscn
+++ b/half-earth/nodes/game.tscn
@@ -1,4 +1,4 @@
-[gd_scene load_steps=7 format=2]
+[gd_scene load_steps=8 format=2]
 
 [ext_resource path="res://nodes/grid.tscn" type="PackedScene" id=1]
 [ext_resource path="res://nodes/grid_cursor.tscn" type="PackedScene" id=2]
@@ -7,16 +7,20 @@
 [ext_resource path="res://nodes/interaction_mode.tscn" type="PackedScene" id=5]
 [ext_resource path="res://nodes/ui/build_mode_ui.tscn" type="PackedScene" id=6]
 
+[sub_resource type="Curve" id=1]
+_data = [ Vector2( 0, 0 ), 0.0, 5.0, 0, 0, Vector2( 0.5, 1 ), 0.0, 0.0, 0, 0, Vector2( 1, 0 ), -4.0, 0.0, 0, 0 ]
+
 [node name="Root" type="Node"]
 
+[node name="Clock" parent="." instance=ExtResource( 4 )]
+_autoTick = true
+
 [node name="Grid" parent="." instance=ExtResource( 1 )]
 DiffusionCoefficient = 0.1
 
 [node name="Cursor" parent="." instance=ExtResource( 2 )]
 Grid = NodePath("../Grid")
-
-[node name="Clock" parent="." instance=ExtResource( 4 )]
-_autoTick = true
+_pulseShape = SubResource( 1 )
 
 [node name="Interaction Mode" parent="." instance=ExtResource( 5 )]
 
@@ -31,6 +35,7 @@ anchor_bottom = 1.0
 [connection signal="OnPauseChanged" from="Clock" to="UI/Debug" method="_on_Clock_OnPauseChanged"]
 [connection signal="OnTick" from="Clock" to="Grid" method="_on_Clock_OnTick"]
 [connection signal="OnTick" from="Clock" to="UI/Debug" method="_on_Clock_OnTick"]
+[connection signal="OnInteractionModeChanged" from="Interaction Mode" to="Cursor" method="_on_Interaction_Mode_OnInteractionModeChanged"]
 [connection signal="OnInteractionModeChanged" from="Interaction Mode" to="UI/Debug" method="_on_Interaction_Mode_OnInteractionModeChanged"]
 [connection signal="OnInteractionModeChanged" from="Interaction Mode" to="UI/Build Mode" method="_on_Interaction_Mode_OnInteractionModeChanged"]
 [connection signal="OnExit" from="UI/Build Mode" to="Interaction Mode" method="Reset"]
diff --git a/half-earth/scripts/GridCursor.cs b/half-earth/scripts/GridCursor.cs
index c2f1631..8159385 100644
--- a/half-earth/scripts/GridCursor.cs
+++ b/half-earth/scripts/GridCursor.cs
@@ -8,6 +8,17 @@ public class GridCursor : Sprite
     private WorldGrid _grid;
     private ShaderMaterial _material;
 
+    #region Animation
+    [Export]
+    private Curve _pulseShape;
+    [Export]
+    private float _pulseRate = 1.0f;
+    private float PulsePeriod => 1.0f / _pulseRate;
+    #endregion
+
+    private float _elapsed = 0.0f;
+    private bool _pulsing = false;
+
     private const string T = "t";
 
     public override void _Ready()
@@ -48,4 +59,33 @@ public class GridCursor : Sprite
             }
         }
     }
+
+    public override void _Process(float delta)
+    {
+        _elapsed += delta * _pulseRate;
+
+        if (!_pulsing)
+        {
+            _material.SetShaderParam(T, 1f);
+            return;
+        }
+
+        var a = _pulseShape.Interpolate(_elapsed % 1.0f);
+        _material.SetShaderParam(T, a);
+    }
+
+
+    public void _on_Interaction_Mode_OnInteractionModeChanged(InteractionMode.Mode oldMode, InteractionMode.Mode newMode)
+    {
+        switch (newMode)
+        {
+            case InteractionMode.Mode.SELECT:
+                _pulsing = false;
+                break;
+
+            case InteractionMode.Mode.BUILD:
+                _pulsing = true;
+                break;
+        }
+    }
 }