1 files changed, 60 insertions, 0 deletions

diff --git a/simloop/test/simloop_test.c b/simloop/test/simloop_test.c
new file mode 100644
index 0000000..3f2aa46
--- /dev/null
+++ b/simloop/test/simloop_test.c
@@ -0,0 +1,60 @@
+#include <simloop.h>
+
+#include <test.h>
+#include <timer.h>
+
+/// An initial render should always trigger on frame 0.
+TEST_CASE(simloop_initial_render) {
+  constexpr int UPDATE_FPS = 10;
+
+  Timer      timer   = {};
+  Simloop    simloop = simloop_make(&(SimloopArgs){
+         .update_fps = UPDATE_FPS, .max_render_fps = 0, .timer = &timer});
+  SimloopOut simout;
+
+  simloop_update(&simloop, &simout);
+  TEST_TRUE(simout.should_render);
+}
+
+/// A simulation loop with no render frame cap.
+TEST_CASE(simloop_test_no_render_frame_cap) {
+  constexpr int    UPDATE_FPS   = 10;
+  const time_delta STEP         = sec_to_time_delta(1);
+  const time_delta SIM_TIME_SEC = sec_to_time_delta(30);
+
+  Timer      timer   = {};
+  Simloop    simloop = simloop_make(&(SimloopArgs){
+         .update_fps = UPDATE_FPS, .max_render_fps = 0, .timer = &timer});
+  SimloopOut simout;
+
+  for (time_delta t = STEP; t < SIM_TIME_SEC; t += STEP) {
+    timer_advance(&timer, t);
+    simloop_update(&simloop, &simout);
+    TEST_TRUE(simout.should_render);
+    TEST_EQUAL(simout.updates_pending, UPDATE_FPS);
+  }
+}
+
+/// A simulation loop with a render frame cap.
+TEST_CASE(simloop_test_with_render_frame_cap) {
+  constexpr int    UPDATE_FPS    = 10;
+  constexpr int    RENDER_FPS    = 5;
+  const time_delta STEP          = sec_to_time_delta(0.1);
+  const time_delta SIM_TIME_SEC  = sec_to_time_delta(30);
+  const time_delta EXPECT_UPDATE = sec_to_time_delta(1.0 / (double)UPDATE_FPS);
+  const time_delta EXPECT_RENDER = sec_to_time_delta(1.0 / (double)RENDER_FPS);
+
+  Timer      timer   = {};
+  Simloop    simloop = simloop_make(&(SimloopArgs){
+         .update_fps = UPDATE_FPS, .max_render_fps = 0, .timer = &timer});
+  SimloopOut simout;
+
+  for (time_delta t = STEP; t < SIM_TIME_SEC; t += STEP) {
+    timer_advance(&timer, t);
+    simloop_update(&simloop, &simout);
+    TEST_TRUE(((STEP % EXPECT_RENDER) == 0) ? simout.should_render : true);
+    TEST_TRUE(((STEP % EXPECT_UPDATE) == 0) ? simout.updates_pending : true);
+  }
+}
+
+int main() { return 0; }