Read glTF perspective camera aspectRatio (#3016)

Co-authored-by: Lay-quq <187484661+Lay-quq@users.noreply.github.com>
Co-authored-by: Riccardo Balbo <riccardo0blb@gmail.com>

Author: Lay-quq

jme3-plugins/src/gltf/java/com/jme3/scene/plugins/gltf/GltfLoader.java

@@ -972,7 +972,7 @@ public void readCameras() throws IOException {
             assertNotNull(type, "No type defined for camera");
             JsonObject camData = camObj.getAsJsonObject(type);
             if (type.equals("perspective")) {
-                float aspectRatio = getAsFloat(camData, "aspectRation", 1f);
+                float aspectRatio = getAsFloat(camData, "aspectRatio", 1f);
                 Float yfov = getAsFloat(camData, "yfov");
                 assertNotNull(yfov, "No yfov for perspective camera");
                 Float zNear = getAsFloat(camData, "znear");

jme3-plugins/src/test/java/com/jme3/scene/plugins/gltf/GltfLoaderTest.java

@@ -44,6 +44,8 @@
 import com.jme3.material.plugin.TestMaterialWrite;
 import com.jme3.math.ColorRGBA;
 import com.jme3.math.Vector3f;
+import com.jme3.renderer.Camera;
+import com.jme3.scene.CameraNode;
 import com.jme3.scene.Geometry;
 import com.jme3.scene.Mesh;
 import com.jme3.scene.Node;
@@ -168,6 +170,27 @@ public void testDracoExtension() {
         }
     }
 
+    @Test
+    public void testPerspectiveCameraAspectRatio() {
+        Camera camera = loadCamera("gltf/camera/perspectiveCamera.gltf");
+        float aspectRatio = camera.getFrustumRight() / camera.getFrustumTop();
+        Assertions.assertEquals(1.5f, aspectRatio, 1e-5f);
+    }
+
+    @Test
+    public void testPerspectiveCameraWithoutAspectRatio() {
+        Camera camera = loadCamera("gltf/camera/perspectiveCameraNoAspectRatio.gltf");
+        float aspectRatio = camera.getFrustumRight() / camera.getFrustumTop();
+        Assertions.assertEquals(1f, aspectRatio, 1e-5f);
+    }
+
+    private Camera loadCamera(String path) {
+        Node scene = (Node) assetManager.loadModel(path);
+        Spatial cameraNode = scene.getChild("cameraNode");
+        Assertions.assertInstanceOf(CameraNode.class, cameraNode, "Camera node not found");
+        return ((CameraNode) cameraNode).getCamera();
+    }
+
     private void dumpScene(Spatial s, int indent) {
         System.err.print(indentString.substring(0, indent) + s.getName() + " (" + s.getClass().getSimpleName() + ") / " +
                 s.getLocalTransform().getTranslation().toString() + ", " +

jme3-plugins/src/test/resources/gltf/README.md

@@ -10,4 +10,8 @@ Used in `com.jme3.scene.plugins.gltf.GltfLoaderTest`
   11x11 vertices, and texture coordinates that are stored as (normalized) unsigned
   short values. The asset is draco-compressed, to check the behavior of the Draco
   extension handler.
+- `camera/perspectiveCamera.gltf` and `camera/perspectiveCameraNoAspectRatio.gltf`
+  contain a single node with a perspective camera, with and without an
+  `aspectRatio`, to check that the camera frustum uses the aspect ratio
+  from the file.
 

jme3-plugins/src/test/resources/gltf/camera/perspectiveCamera.gltf

@@ -0,0 +1,12 @@
+{
+  "asset": { "version": "2.0" },
+  "scene": 0,
+  "scenes": [ { "nodes": [ 0 ] } ],
+  "nodes": [ { "name": "cameraNode", "camera": 0 } ],
+  "cameras": [
+    {
+      "type": "perspective",
+      "perspective": { "aspectRatio": 1.5, "yfov": 0.8, "znear": 0.1, "zfar": 100.0 }
+    }
+  ]
+}

jme3-plugins/src/test/resources/gltf/camera/perspectiveCameraNoAspectRatio.gltf

@@ -0,0 +1,12 @@
+{
+  "asset": { "version": "2.0" },
+  "scene": 0,
+  "scenes": [ { "nodes": [ 0 ] } ],
+  "nodes": [ { "name": "cameraNode", "camera": 0 } ],
+  "cameras": [
+    {
+      "type": "perspective",
+      "perspective": { "yfov": 0.8, "znear": 0.1, "zfar": 100.0 }
+    }
+  ]
+}