Avoid draw list and shadow map update in the same frame to reduce dtime jitter (#11393)

* Separate draw list and shadows update to reduce jitter

* Avoid draw list update and shadow update in the same frame

* Force-update shadows when camera offset changes

1 files changed, 14 insertions, 3 deletions

diff --git a/src/client/game.cpp b/src/client/game.cpp
index 9f643e611..134c74d5d 100644
--- a/src/client/game.cpp
+++ b/src/client/game.cpp
@@ -609,6 +609,7 @@ struct GameRunData {
 	float jump_timer;
 	float damage_flash;
 	float update_draw_list_timer;
+	float update_shadows_timer;
 
 	f32 fog_range;
 
@@ -3874,10 +3875,10 @@ void Game::updateFrame(ProfilerGraph *graph, RunStats *stats, f32 dtime,
 		changed much
 	*/
 	runData.update_draw_list_timer += dtime;
+	runData.update_shadows_timer += dtime;
 
 	float update_draw_list_delta = 0.2f;
-	if (ShadowRenderer *shadow = RenderingEngine::get_shadow_renderer())
-		update_draw_list_delta = shadow->getUpdateDelta();
+	bool draw_list_updated = false;
 
 	v3f camera_direction = camera->getDirection();
 	if (runData.update_draw_list_timer >= update_draw_list_delta
@@ -3887,8 +3888,18 @@ void Game::updateFrame(ProfilerGraph *graph, RunStats *stats, f32 dtime,
 		runData.update_draw_list_timer = 0;
 		client->getEnv().getClientMap().updateDrawList();
 		runData.update_draw_list_last_cam_dir = camera_direction;
+		draw_list_updated = true;
+	}
 
-		updateShadows();
+	if (ShadowRenderer *shadow = RenderingEngine::get_shadow_renderer()) {
+		update_draw_list_delta = shadow->getUpdateDelta();
+
+		if (m_camera_offset_changed ||
+				(runData.update_shadows_timer > update_draw_list_delta &&
+				(!draw_list_updated || shadow->getDirectionalLightCount() == 0))) {
+			runData.update_shadows_timer = 0;
+			updateShadows();
+		}
 	}
 
 	m_game_ui->update(*stats, client, draw_control, cam, runData.pointed_old, gui_chat_console, dtime);