Allow the server to control fog_distance and fog_start via the sky-api (#13448)

client/shaders/nodes_shader/opengl_fragment.glsl

@@ -3,6 +3,7 @@ uniform sampler2D baseTexture;
 uniform vec3 dayLight;
 uniform vec4 skyBgColor;
 uniform float fogDistance;
+uniform float fogShadingParameter;
 uniform vec3 eyePosition;
 
 // The cameraOffset is the current center of the visible world.
@@ -49,9 +50,6 @@ varying vec3 tsEyeVec;
 varying vec3 lightVec;
 varying vec3 tsLightVec;
 
-const float fogStart = FOG_START;
-const float fogShadingParameter = 1.0 / ( 1.0 - fogStart);
-
 #ifdef ENABLE_DYNAMIC_SHADOWS
 
 // assuming near is always 1.0

client/shaders/object_shader/opengl_fragment.glsl

@@ -3,6 +3,7 @@ uniform sampler2D baseTexture;
 uniform vec3 dayLight;
 uniform vec4 skyBgColor;
 uniform float fogDistance;
+uniform float fogShadingParameter;
 uniform vec3 eyePosition;
 
 // The cameraOffset is the current center of the visible world.
@@ -48,9 +49,6 @@ varying float nightRatio;
 
 varying float vIDiff;
 
-const float fogStart = FOG_START;
-const float fogShadingParameter = 1.0 / (1.0 - fogStart);
-
 #ifdef ENABLE_DYNAMIC_SHADOWS
 
 // assuming near is always 1.0

doc/lua_api.md

@@ -7740,6 +7740,18 @@ child will follow movement and rotation of that bone.
                 abides by, `"custom"` uses `sun_tint` and `moon_tint`, while
                 `"default"` uses the classic Minetest sun and moon tinting.
                 Will use tonemaps, if set to `"default"`. (default: `"default"`)
+        * `fog`: A table with following optional fields:
+            * `fog_distance`: integer, set an upper bound the client's viewing_range (inluding range_all).
+               By default, fog_distance is controlled by the client's viewing_range, and this field is not set.
+               Any value >= 0 sets the desired upper bound for the client's viewing_range and disables range_all.
+               Any value < 0, resets the behavior to being client-controlled.
+               (default: -1)
+            * `fog_start`: float, override the client's fog_start.
+               Fraction of the visible distance at which fog starts to be rendered.
+               By default, fog_start is controlled by the client's `fog_start` setting, and this field is not set.
+               Any value between [0.0, 0.99] set the fog_start as a fraction of the viewing_range.
+               Any value < 0, resets the behavior to being client-controlled.
+               (default: -1)
 * `set_sky(base_color, type, {texture names}, clouds)`
     * Deprecated. Use `set_sky(sky_parameters)`
     * `base_color`: ColorSpec, defaults to white

src/client/game.cpp

@@ -372,6 +372,7 @@ class GameGlobalShaderConstantSetter : public IShaderConstantSetter
 	bool m_fog_enabled;
 	CachedPixelShaderSetting<float, 4> m_sky_bg_color;
 	CachedPixelShaderSetting<float> m_fog_distance;
+	CachedPixelShaderSetting<float> m_fog_shading_parameter;
 	CachedVertexShaderSetting<float> m_animation_timer_vertex;
 	CachedPixelShaderSetting<float> m_animation_timer_pixel;
 	CachedVertexShaderSetting<float> m_animation_timer_delta_vertex;
@@ -431,6 +432,7 @@ public:
 		m_fog_range(fog_range),
 		m_sky_bg_color("skyBgColor"),
 		m_fog_distance("fogDistance"),
+		m_fog_shading_parameter("fogShadingParameter"),
 		m_animation_timer_vertex("animationTimer"),
 		m_animation_timer_pixel("animationTimer"),
 		m_animation_timer_delta_vertex("animationTimerDelta"),
@@ -496,7 +498,10 @@ public:
 		if (m_fog_enabled && !*m_force_fog_off)
 			fog_distance = *m_fog_range;
 
+		float fog_shading_parameter = 1.0 / ( 1.0 - m_sky->getFogStart());
+
 		m_fog_distance.set(&fog_distance, services);
+		m_fog_shading_parameter.set(&fog_shading_parameter, services);
 
 		u32 daynight_ratio = (float)m_client->getEnv().getDayNightRatio();
 		video::SColorf sunlight;
@@ -961,7 +966,6 @@ private:
 	f32  m_cache_joystick_frustum_sensitivity;
 	f32  m_repeat_place_time;
 	f32  m_cache_cam_smoothing;
-	f32  m_cache_fog_start;
 
 	bool m_invert_mouse;
 	bool m_enable_hotbar_mouse_wheel;
@@ -2490,6 +2494,9 @@ void Game::increaseViewRange()
 		range_new = 4000;
 		std::wstring msg = fwgettext("Viewing range is at maximum: %d", range_new);
 		m_game_ui->showStatusText(msg);
+	} else if (sky->getFogDistance() >= 0 && range_new > sky->getFogDistance()) {
+		std::wstring msg = fwgettext("Viewing range changed to %d, but limited to %d set by server", range_new, sky->getFogDistance());
+		m_game_ui->showStatusText(msg);
 	} else {
 		std::wstring msg = fwgettext("Viewing range changed to %d", range_new);
 		m_game_ui->showStatusText(msg);
@@ -2507,6 +2514,9 @@ void Game::decreaseViewRange()
 		range_new = 20;
 		std::wstring msg = fwgettext("Viewing range is at minimum: %d", range_new);
 		m_game_ui->showStatusText(msg);
+	} else if (sky->getFogDistance() >= 0 && range_new > sky->getFogDistance()) {
+		std::wstring msg = fwgettext("Viewing range changed to %d, but limited to %d set by server", range_new, sky->getFogDistance());
+		m_game_ui->showStatusText(msg);
 	} else {
 		std::wstring msg = fwgettext("Viewing range changed to %d", range_new);
 		m_game_ui->showStatusText(msg);
@@ -2518,10 +2528,15 @@ void Game::decreaseViewRange()
 void Game::toggleFullViewRange()
 {
 	draw_control->range_all = !draw_control->range_all;
-	if (draw_control->range_all)
+	if (draw_control->range_all) {
-		m_game_ui->showTranslatedStatusText("Enabled unlimited viewing range");
+		if (sky->getFogDistance() >= 0) {
-	else
+			m_game_ui->showTranslatedStatusText("The server has disabled unlimited viewing range");
+		} else {
+			m_game_ui->showTranslatedStatusText("Enabled unlimited viewing range");
+		}
+	} else {
 		m_game_ui->showTranslatedStatusText("Disabled unlimited viewing range");
+	}
 }
 
 
@@ -2996,6 +3011,20 @@ void Game::handleClientEvent_SetSky(ClientEvent *event, CameraOrientation *cam)
 	// Orbit Tilt:
 	sky->setBodyOrbitTilt(event->set_sky->body_orbit_tilt);
 
+	// fog
+	// do not override a potentially smaller client setting.
+	sky->setFogDistance(event->set_sky->fog_distance);
+
+	// if the fog distance is reset, switch back to the client's viewing_range
+	if (event->set_sky->fog_distance < 0)
+		draw_control->wanted_range = g_settings->getS16("viewing_range");
+
+	if (event->set_sky->fog_start >= 0)
+		sky->setFogStart(rangelim(event->set_sky->fog_start, 0.0f, 0.99f));
+	else
+		sky->setFogStart(rangelim(g_settings->getFloat("fog_start"), 0.0f, 0.99f));
+
+
 	delete event->set_sky;
 }
 
@@ -3915,7 +3944,10 @@ void Game::updateFrame(ProfilerGraph *graph, RunStats *stats, f32 dtime,
 		Fog range
 	*/
 
-	if (draw_control->range_all) {
+	if (sky->getFogDistance() >= 0) {
+		draw_control->wanted_range = MYMIN(draw_control->wanted_range, sky->getFogDistance());
+	}
+	if (draw_control->range_all && sky->getFogDistance() < 0) {
 		runData.fog_range = 100000 * BS;
 	} else {
 		runData.fog_range = draw_control->wanted_range * BS;
@@ -4006,12 +4038,11 @@ void Game::updateFrame(ProfilerGraph *graph, RunStats *stats, f32 dtime,
 	/*
 		Fog
 	*/
-
 	if (m_cache_enable_fog) {
 		driver->setFog(
 				sky->getBgColor(),
 				video::EFT_FOG_LINEAR,
-				runData.fog_range * m_cache_fog_start,
+				runData.fog_range * sky->getFogStart(),
 				runData.fog_range * 1.0,
 				0.01,
 				false, // pixel fog
@@ -4284,15 +4315,12 @@ void Game::readSettings()
 	m_cache_enable_noclip                = g_settings->getBool("noclip");
 	m_cache_enable_free_move             = g_settings->getBool("free_move");
 
-	m_cache_fog_start                    = g_settings->getFloat("fog_start");
-
 	m_cache_cam_smoothing = 0;
 	if (g_settings->getBool("cinematic"))
 		m_cache_cam_smoothing = 1 - g_settings->getFloat("cinematic_camera_smoothing");
 	else
 		m_cache_cam_smoothing = 1 - g_settings->getFloat("camera_smoothing");
 
-	m_cache_fog_start = rangelim(m_cache_fog_start, 0.0f, 0.99f);
 	m_cache_cam_smoothing = rangelim(m_cache_cam_smoothing, 0.01f, 1.0f);
 	m_cache_mouse_sensitivity = rangelim(m_cache_mouse_sensitivity, 0.001, 100.0);
 

src/client/shader.cpp

@@ -752,8 +752,6 @@ ShaderInfo ShaderSource::generateShader(const std::string &name,
 	shaders_header << "#define ENABLE_WAVING_PLANTS " << g_settings->getBool("enable_waving_plants") << "\n";
 	shaders_header << "#define ENABLE_TONE_MAPPING " << g_settings->getBool("tone_mapping") << "\n";
 
-	shaders_header << "#define FOG_START " << core::clamp(g_settings->getFloat("fog_start"), 0.0f, 0.99f) << "\n";
-
 	if (g_settings->getBool("enable_dynamic_shadows")) {
 		shaders_header << "#define ENABLE_DYNAMIC_SHADOWS 1\n";
 		if (g_settings->getBool("shadow_map_color"))

src/client/sky.cpp

@@ -98,6 +98,7 @@ Sky::Sky(s32 id, RenderingEngine *rendering_engine, ITextureSource *tsrc, IShade
 
 	m_directional_colored_fog = g_settings->getBool("directional_colored_fog");
 	m_sky_params.body_orbit_tilt = g_settings->getFloat("shadow_sky_body_orbit_tilt", -60., 60.);
+	m_sky_params.fog_start = rangelim(g_settings->getFloat("fog_start"), 0.0f, 0.99f);
 
 	setStarCount(1000);
 }

src/client/sky.h

@@ -114,6 +114,11 @@ public:
 	void addTextureToSkybox(const  std::string &texture, int material_id,
 		ITextureSource *tsrc);
 	const video::SColorf &getCurrentStarColor() const { return m_star_color; }
+	void setFogDistance(s16 fog_distance) { m_sky_params.fog_distance = fog_distance; }
+	s16 getFogDistance() const { return m_sky_params.fog_distance; }
+
+	void setFogStart(float fog_start) { m_sky_params.fog_start = fog_start; }
+	float getFogStart() const { return m_sky_params.fog_start; }
 
 private:
 	aabb3f m_box;

src/network/clientpackethandler.cpp

@@ -1395,9 +1395,13 @@ void Client::handleCommand_HudSetSky(NetworkPacket* pkt)
 				>> skybox.sky_color.indoors;
 		}
 
-		try {
+		if (pkt->getRemainingBytes() >= 4) {
 			*pkt >> skybox.body_orbit_tilt;
-		} catch (PacketError &e) {}
+		}
+
+		if (pkt->getRemainingBytes() >= 6) {
+			*pkt >> skybox.fog_distance >> skybox.fog_start;
+		}
 
 		ClientEvent *event = new ClientEvent();
 		event->type = CE_SET_SKY;

src/script/lua_api/l_object.cpp

@@ -1803,6 +1803,11 @@ int ObjectRef::l_set_sky(lua_State *L)
 			// pop "sky_color" table
 			lua_pop(L, 1);
 		}
+		lua_getfield(L, 2, "fog");
+		if (lua_istable(L, -1)) {
+			sky_params.fog_distance = getintfield_default(L, -1,  "fog_distance", sky_params.fog_distance);
+			sky_params.fog_start = getfloatfield_default(L, -1,  "fog_start", sky_params.fog_start);
+		}
 	} else {
 		// Handle old set_sky calls, and log deprecated:
 		log_deprecated(L, "Deprecated call to set_sky, please check lua_api.md");
@@ -1923,7 +1928,6 @@ int ObjectRef::l_get_sky(lua_State *L)
 		lua_pushnumber(L, skybox_params.body_orbit_tilt);
 		lua_setfield(L, -2, "body_orbit_tilt");
 	}
-
 	lua_newtable(L);
 	s16 i = 1;
 	for (const std::string &texture : skybox_params.textures) {
@@ -1936,6 +1940,14 @@ int ObjectRef::l_get_sky(lua_State *L)
 
 	push_sky_color(L, skybox_params);
 	lua_setfield(L, -2, "sky_color");
+
+	lua_newtable(L); // fog
+	lua_pushinteger(L, skybox_params.fog_distance >= 0 ? skybox_params.fog_distance : -1);
+	lua_setfield(L, -2, "fog_distance");
+	lua_pushnumber(L, skybox_params.fog_start >= 0 ? skybox_params.fog_start : -1.0f);
+	lua_setfield(L, -2, "fog_start");
+	lua_setfield(L, -2, "fog");
+
 	return 1;
 }
 

src/server.cpp

@@ -1846,6 +1846,7 @@ void Server::SendSetSky(session_t peer_id, const SkyboxParams &params)
 		}
 
 		pkt << params.body_orbit_tilt;
+		pkt << params.fog_distance << params.fog_start;
 	}
 
 	Send(&pkt);

src/skyparams.h

@@ -44,6 +44,8 @@ struct SkyboxParams
 	video::SColor fog_moon_tint;
 	std::string fog_tint_type;
 	float body_orbit_tilt { INVALID_SKYBOX_TILT };
+	s16 fog_distance { -1 };
+	float fog_start { -1.0f };
 };
 
 struct SunParams