Add simple unit test for mjv_updateScene.

PiperOrigin-RevId: 709334033
Change-Id: I69adc1d3ad0565f3684346749a372894d12ce99a

test/engine/CMakeLists.txt

@@ -73,3 +73,5 @@ mujoco_test(
   ENVIRONMENT
   "MUJOCO_PLUGIN_DIR=$<TARGET_FILE_DIR:elasticity>"
 )
+
+mujoco_test(engine_vis_visualize_test)

test/engine/engine_vis_visualize_test.cc

@@ -0,0 +1,81 @@
+// Copyright 2024 DeepMind Technologies Limited
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <cstring>
+#include <string>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <mujoco/mjvisualize.h>
+#include <mujoco/mujoco.h>
+#include "test/fixture.h"
+
+namespace mujoco {
+namespace {
+
+using ::testing::NotNull;
+using MjvSceneTest = MujocoTest;
+
+constexpr int kMaxGeom = 10000;
+
+static const char* const kModelPath = "testdata/model.xml";
+
+TEST_F(MjvSceneTest, UpdateScene) {
+  for (const char* path : {kModelPath}) {
+    const std::string xml_path = GetTestDataFilePath(path);
+    mjModel* model = mj_loadXML(xml_path.c_str(), nullptr, 0, 0);
+    ASSERT_THAT(model, NotNull()) << "Failed to load model from " << path;
+    mjData* data = mj_makeData(model);
+
+    while (data->time < .2) {
+      mj_step(model, data);
+    }
+
+    mjvScene scn;
+    mjv_defaultScene(&scn);
+    mjv_makeScene(model, &scn, kMaxGeom);
+
+    mjvOption opt;
+    mjv_defaultOption(&opt);
+
+    mjvPerturb pert;
+    mjv_defaultPerturb(&pert);
+
+    mjvCamera cam;
+    mjv_defaultFreeCamera(model, &cam);
+
+    // Enable all flags to exercise all code paths
+    for (int i = 0; i < mjNVISFLAG; ++i) {
+      opt.flags[i] = 1;
+    }
+
+    mjv_updateScene(model, data, &opt, &pert, &cam, mjCAT_ALL, &scn);
+    EXPECT_GT(scn.ngeom, 0);
+    if (model->nskin) EXPECT_GT(scn.nskin, 0);
+    EXPECT_GT(scn.nlight, 0);
+
+    mjv_updateScene(model, data, &opt, &pert, &cam, mjCAT_ALL, &scn);
+
+    // call mj_copyData to expose any memory leaks mjv_updateScene.
+    mjData* data_copy = mj_copyData(nullptr, model, data);
+
+    mjv_freeScene(&scn);
+    mj_deleteData(data_copy);
+    mj_deleteData(data);
+    mj_deleteModel(model);
+  }
+}
+
+}  // namespace
+}  // namespace mujoco