assets: add animated test backpack

src/main/resources/assets/citrus-dev/geckolib/animations/backpack.animation.json

@@ -0,0 +1,18 @@
+{
+  "format_version": "1.8.0",
+  "animations": {
+    "animation.backpack.idle": {
+      "loop": true,
+      "animation_length": 2.0,
+      "bones": {
+        "flap": {
+          "rotation": {
+            "0.0": [0, 0, 0],
+            "1.0": [2, 0, 0],
+            "2.0": [0, 0, 0]
+          }
+        }
+      }
+    }
+  }
+}

src/main/resources/assets/citrus-dev/geckolib/models/player/backpack.geo.json

@@ -0,0 +1,50 @@
+{
+  "format_version": "1.12.0",
+  "minecraft:geometry": [
+    {
+      "description": {
+        "identifier": "geometry.citrus_backpack",
+        "texture_width": 32,
+        "texture_height": 32,
+        "visible_bounds_width": 2,
+        "visible_bounds_height": 3,
+        "visible_bounds_offset": [0, 1, 0]
+      },
+      "bones": [
+        {
+          "name": "root",
+          "pivot": [0, 0, 0]
+        },
+        {
+          "name": "backpack",
+          "parent": "root",
+          "pivot": [0, 1, 2],
+          "cubes": [
+            {
+              "origin": [-4, 1, 2],
+              "size": [8, 10, 4],
+              "uv": [0, 0]
+            },
+            {
+              "origin": [-3, 3, 6],
+              "size": [6, 5, 1],
+              "uv": [0, 16]
+            }
+          ]
+        },
+        {
+          "name": "flap",
+          "parent": "backpack",
+          "pivot": [0, 2, 6],
+          "cubes": [
+            {
+              "origin": [-3.5, 1, 5.75],
+              "size": [7, 3, 1],
+              "uv": [14, 16]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}