Add clouds API

17 files changed, 357 insertions, 50 deletions

diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index eba8a5fef..479e38a2e 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -3077,6 +3077,15 @@ This is basically a reference to a C++ `ServerActiveObject`
         * `"skybox"`: Uses 6 textures, `bgcolor` used
         * `"plain"`: Uses 0 textures, `bgcolor` used
 * `get_sky()`: returns bgcolor, type and a table with the textures
+* `set_clouds(parameters)`: set cloud parameters
+	* `parameters` is a table with the following optional fields:
+		* `density`: from `0` (no clouds) to `1` (full clouds) (default `0.4`)
+		* `color`: basic cloud color, with alpha channel (default `#fff0f0e5`)
+		* `ambient`: cloud color lower bound, use for a "glow at night" effect (default `#000000`)
+		* `height`: cloud height, i.e. y of cloud base (default per conf, usually `120`)
+		* `thickness`: cloud thickness in nodes (default `16`)
+		* `speed`: 2D cloud speed + direction in nodes per second (default `{x=0, y=-2}`)
+* `get_clouds()`: returns a table with the current cloud parameters as in `set_clouds`
 * `override_day_night_ratio(ratio or nil)`
     * `0`...`1`: Overrides day-night ratio, controlling sunlight to a specific amount
     * `nil`: Disables override, defaulting to sunlight based on day-night cycle
diff --git a/src/client.h b/src/client.h
index f5b03f19d..7cbfadd50 100644
--- a/src/client.h
+++ b/src/client.h
@@ -77,6 +77,7 @@ enum ClientEventType
 	CE_HUDCHANGE,
 	CE_SET_SKY,
 	CE_OVERRIDE_DAY_NIGHT_RATIO,
+	CE_CLOUD_PARAMS,
 };
 
 struct ClientEvent
@@ -178,6 +179,15 @@ struct ClientEvent
 			bool do_override;
 			float ratio_f;
 		} override_day_night_ratio;
+		struct {
+			f32 density;
+			u32 color_bright;
+			u32 color_ambient;
+			f32 height;
+			f32 thickness;
+			f32 speed_x;
+			f32 speed_y;
+		} cloud_params;
 	};
 };
 
@@ -331,6 +341,7 @@ public:
 	void handleCommand_HudSetFlags(NetworkPacket* pkt);
 	void handleCommand_HudSetParam(NetworkPacket* pkt);
 	void handleCommand_HudSetSky(NetworkPacket* pkt);
+	void handleCommand_CloudParams(NetworkPacket* pkt);
 	void handleCommand_OverrideDayNightRatio(NetworkPacket* pkt);
 	void handleCommand_LocalPlayerAnimations(NetworkPacket* pkt);
 	void handleCommand_EyeOffset(NetworkPacket* pkt);
diff --git a/src/cloudparams.h b/src/cloudparams.h
new file mode 100644
index 000000000..dafec4b27
--- /dev/null
+++ b/src/cloudparams.h
@@ -0,0 +1,33 @@
+/*
+Minetest
+Copyright (C) 2017 bendeutsch, Ben Deutsch <ben@bendeutsch.de>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef CLOUDPARAMS_HEADER
+#define CLOUDPARAMS_HEADER
+
+struct CloudParams
+{
+	float density;
+	video::SColor color_bright;
+	video::SColor color_ambient;
+	float thickness;
+	float height;
+	v2f speed;
+};
+
+#endif
diff --git a/src/clouds.cpp b/src/clouds.cpp
index 82b63b6b3..627fac47a 100644
--- a/src/clouds.cpp
+++ b/src/clouds.cpp
@@ -32,6 +32,7 @@ irr::scene::ISceneManager *g_menucloudsmgr = NULL;
 
 static void cloud_3d_setting_changed(const std::string &settingname, void *data)
 {
+	// TODO: only re-read cloud settings, not height or radius
 	((Clouds *)data)->readSettings();
 }
 
@@ -44,9 +45,10 @@ Clouds::Clouds(
 ):
 	scene::ISceneNode(parent, mgr, id),
 	m_seed(seed),
-	m_camera_pos(0,0),
-	m_time(0),
-	m_camera_offset(0,0,0)
+	m_camera_pos(0.0f, 0.0f),
+	m_origin(0.0f, 0.0f),
+	m_camera_offset(0.0f, 0.0f, 0.0f),
+	m_color(1.0f, 1.0f, 1.0f, 1.0f)
 {
 	m_material.setFlag(video::EMF_LIGHTING, false);
 	//m_material.setFlag(video::EMF_BACK_FACE_CULLING, false);
@@ -57,14 +59,18 @@ Clouds::Clouds(
 	//m_material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
 	m_material.MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL;
 
+	m_params.density       = 0.4f;
+	m_params.thickness     = 16.0f;
+	m_params.color_bright  = video::SColor(229, 255, 240, 240);
+	m_params.color_ambient = video::SColor(255, 0, 0, 0);
+	m_params.speed         = v2f(0.0f, -2.0f);
+
 	m_passed_cloud_y = cloudheight;
 	readSettings();
 	g_settings->registerChangedCallback("enable_3d_clouds",
 		&cloud_3d_setting_changed, this);
 
-	m_box = aabb3f(-BS*1000000,m_cloud_y-BS,-BS*1000000,
-			BS*1000000,m_cloud_y+BS,BS*1000000);
-
+	updateBox();
 }
 
 Clouds::~Clouds()
@@ -88,6 +94,10 @@ void Clouds::OnRegisterSceneNode()
 
 void Clouds::render()
 {
+
+	if (m_params.density <= 0.0f)
+		return; // no need to do anything
+
 	video::IVideoDriver* driver = SceneManager->getVideoDriver();
 
 	if(SceneManager->getSceneNodeRenderPass() != scene::ESNRP_TRANSPARENT)
@@ -107,15 +117,12 @@ void Clouds::render()
 		Clouds move from Z+ towards Z-
 	*/
 
-	const float cloud_size = BS * 64;
-	const v2f cloud_speed(0, -BS * 2);
+	static const float cloud_size = BS * 64.0f;
 	
 	const float cloud_full_radius = cloud_size * m_cloud_radius_i;
 	
-	// Position of cloud noise origin in world coordinates
-	v2f world_cloud_origin_pos_f = m_time * cloud_speed;
 	// Position of cloud noise origin from the camera
-	v2f cloud_origin_from_camera_f = world_cloud_origin_pos_f - m_camera_pos;
+	v2f cloud_origin_from_camera_f = m_origin - m_camera_pos;
 	// The center point of drawing in the noise
 	v2f center_of_drawing_in_noise_f = -cloud_origin_from_camera_f;
 	// The integer center point of drawing in the noise
@@ -127,7 +134,7 @@ void Clouds::render()
 	v2f world_center_of_drawing_in_noise_f = v2f(
 		center_of_drawing_in_noise_i.X * cloud_size,
 		center_of_drawing_in_noise_i.Y * cloud_size
-	) + world_cloud_origin_pos_f;
+	) + m_origin;
 
 	/*video::SColor c_top(128,b*240,b*240,b*255);
 	video::SColor c_side_1(128,b*230,b*230,b*255);
@@ -146,10 +153,6 @@ void Clouds::render()
 	c_bottom_f.r *= 0.80;
 	c_bottom_f.g *= 0.80;
 	c_bottom_f.b *= 0.80;
-	c_top_f.a = 0.9;
-	c_side_1_f.a = 0.9;
-	c_side_2_f.a = 0.9;
-	c_bottom_f.a = 0.9;
 	video::SColor c_top = c_top_f.toSColor();
 	video::SColor c_side_1 = c_side_1_f.toSColor();
 	video::SColor c_side_2 = c_side_2_f.toSColor();
@@ -187,11 +190,14 @@ void Clouds::render()
 				zi + center_of_drawing_in_noise_i.Y
 			);
 
-			double noise = noise2d_perlin(
+			float noise = noise2d_perlin(
 					(float)p_in_noise_i.X * cloud_size_noise,
 					(float)p_in_noise_i.Y * cloud_size_noise,
 					m_seed, 3, 0.5);
-			grid[i] = (noise >= 0.4);
+			// normalize to 0..1 (given 3 octaves)
+			static const float noise_bound = 1.0f + 0.5f + 0.25f;
+			float density = noise / noise_bound * 0.5f + 0.5f;
+			grid[i] = (density < m_params.density);
 		}
 	}
 
@@ -236,8 +242,9 @@ void Clouds::render()
 			v[3].Color.setBlue(255);
 		}*/
 
-		f32 rx = cloud_size/2;
-		f32 ry = 8 * BS;
+		f32 rx = cloud_size / 2.0f;
+		// if clouds are flat, the top layer should be at the given height
+		f32 ry = m_enable_3d ? m_params.thickness * BS : 0.0f;
 		f32 rz = cloud_size / 2;
 
 		for(int i=0; i<num_faces_to_draw; i++)
@@ -265,8 +272,8 @@ void Clouds::render()
 				}
 				v[0].Pos.set(-rx, ry,-rz);
 				v[1].Pos.set( rx, ry,-rz);
-				v[2].Pos.set( rx,-ry,-rz);
-				v[3].Pos.set(-rx,-ry,-rz);
+				v[2].Pos.set( rx,  0,-rz);
+				v[3].Pos.set(-rx,  0,-rz);
 				break;
 			case 2: //right
 				if (INAREA(xi + 1, zi, m_cloud_radius_i)) {
@@ -280,8 +287,8 @@ void Clouds::render()
 				}
 				v[0].Pos.set( rx, ry,-rz);
 				v[1].Pos.set( rx, ry, rz);
-				v[2].Pos.set( rx,-ry, rz);
-				v[3].Pos.set( rx,-ry,-rz);
+				v[2].Pos.set( rx,  0, rz);
+				v[3].Pos.set( rx,  0,-rz);
 				break;
 			case 3: // front
 				if (INAREA(xi, zi + 1, m_cloud_radius_i)) {
@@ -295,8 +302,8 @@ void Clouds::render()
 				}
 				v[0].Pos.set( rx, ry, rz);
 				v[1].Pos.set(-rx, ry, rz);
-				v[2].Pos.set(-rx,-ry, rz);
-				v[3].Pos.set( rx,-ry, rz);
+				v[2].Pos.set(-rx,  0, rz);
+				v[3].Pos.set( rx,  0, rz);
 				break;
 			case 4: // left
 				if (INAREA(xi-1, zi, m_cloud_radius_i)) {
@@ -310,22 +317,22 @@ void Clouds::render()
 				}
 				v[0].Pos.set(-rx, ry, rz);
 				v[1].Pos.set(-rx, ry,-rz);
-				v[2].Pos.set(-rx,-ry,-rz);
-				v[3].Pos.set(-rx,-ry, rz);
+				v[2].Pos.set(-rx,  0,-rz);
+				v[3].Pos.set(-rx,  0, rz);
 				break;
 			case 5: // bottom
 				for(int j=0;j<4;j++){
 					v[j].Color = c_bottom;
 					v[j].Normal.set(0,-1,0);
 				}
-				v[0].Pos.set( rx,-ry, rz);
-				v[1].Pos.set(-rx,-ry, rz);
-				v[2].Pos.set(-rx,-ry,-rz);
-				v[3].Pos.set( rx,-ry,-rz);
+				v[0].Pos.set( rx,  0, rz);
+				v[1].Pos.set(-rx,  0, rz);
+				v[2].Pos.set(-rx,  0,-rz);
+				v[3].Pos.set( rx,  0,-rz);
 				break;
 			}
 
-			v3f pos(p0.X, m_cloud_y, p0.Y);
+			v3f pos(p0.X, m_params.height * BS, p0.Y);
 			pos -= intToFloat(m_camera_offset, BS);
 
 			for(u16 i=0; i<4; i++)
@@ -345,22 +352,25 @@ void Clouds::render()
 
 void Clouds::step(float dtime)
 {
-	m_time += dtime;
+	m_origin = m_origin + dtime * BS * m_params.speed;
 }
 
-void Clouds::update(v2f camera_p, video::SColorf color)
+void Clouds::update(v2f camera_p, video::SColorf color_diffuse)
 {
 	m_camera_pos = camera_p;
-	m_color = color;
-	//m_brightness = brightness;
-	//dstream<<"m_brightness="<<m_brightness<<std::endl;
+	m_color.r = MYMIN(MYMAX(color_diffuse.r * m_params.color_bright.getRed(),
+			m_params.color_ambient.getRed()), 255) / 255.0f;
+	m_color.g = MYMIN(MYMAX(color_diffuse.r * m_params.color_bright.getGreen(),
+			m_params.color_ambient.getGreen()), 255) / 255.0f;
+	m_color.b = MYMIN(MYMAX(color_diffuse.b * m_params.color_bright.getBlue(),
+			m_params.color_ambient.getBlue()), 255) / 255.0f;
+	m_color.a = m_params.color_bright.getAlpha() / 255.0f;
 }
 
 void Clouds::readSettings()
 {
-	m_cloud_y = BS * (m_passed_cloud_y ? m_passed_cloud_y :
+	m_params.height = (m_passed_cloud_y ? m_passed_cloud_y :
 		g_settings->getS16("cloud_height"));
 	m_cloud_radius_i = g_settings->getU16("cloud_radius");
 	m_enable_3d = g_settings->getBool("enable_3d_clouds");
 }
-
diff --git a/src/clouds.h b/src/clouds.h
index 9c6b41786..a0bda28df 100644
--- a/src/clouds.h
+++ b/src/clouds.h
@@ -23,6 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "irrlichttypes_extrabloated.h"
 #include <iostream>
 #include "constants.h"
+#include "cloudparams.h"
 
 // Menu clouds
 class Clouds;
@@ -79,27 +80,68 @@ public:
 	void updateCameraOffset(v3s16 camera_offset)
 	{
 		m_camera_offset = camera_offset;
-		m_box = aabb3f(-BS * 1000000, m_cloud_y - BS - BS * camera_offset.Y, -BS * 1000000,
-			BS * 1000000, m_cloud_y + BS - BS * camera_offset.Y, BS * 1000000);
+		updateBox();
 	}
 
 	void readSettings();
 
+	void setDensity(float density)
+	{
+		m_params.density = density;
+		// currently does not need bounding
+	}
+
+	void setColorBright(const video::SColor &color_bright)
+	{
+		m_params.color_bright = color_bright;
+	}
+
+	void setColorAmbient(const video::SColor &color_ambient)
+	{
+		m_params.color_ambient = color_ambient;
+	}
+
+	void setHeight(float height)
+	{
+		m_params.height = height; // add bounding when necessary
+		updateBox();
+	}
+
+	void setSpeed(v2f speed)
+	{
+		m_params.speed = speed;
+	}
+
+	void setThickness(float thickness)
+	{
+		m_params.thickness = thickness;
+		updateBox();
+	}
+
 private:
+	void updateBox()
+	{
+		float height_bs    = m_params.height    * BS;
+		float thickness_bs = m_params.thickness * BS;
+		m_box = aabb3f(-BS * 1000000.0f, height_bs - BS * m_camera_offset.Y, -BS * 1000000.0f,
+				BS * 1000000.0f, height_bs + thickness_bs - BS * m_camera_offset.Y, BS * 1000000.0f);
+	}
+
 	video::SMaterial m_material;
 	aabb3f m_box;
 	s16 m_passed_cloud_y;
-	float m_cloud_y;
 	u16 m_cloud_radius_i;
 	bool m_enable_3d;
-	video::SColorf m_color;
 	u32 m_seed;
 	v2f m_camera_pos;
-	float m_time;
+	v2f m_origin;
+	v2f m_speed;
 	v3s16 m_camera_offset;
+	video::SColorf m_color;
+	CloudParams m_params;
+
 };
 
 
 
 #endif
-
diff --git a/src/game.cpp b/src/game.cpp
index a1cc1ab15..ba6530d80 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -3295,6 +3295,19 @@ void Game::processClientEvents(CameraOrientation *cam)
 					event.override_day_night_ratio.ratio_f * 1000);
 			break;
 
+		case CE_CLOUD_PARAMS:
+			if (clouds) {
+				clouds->setDensity(event.cloud_params.density);
+				clouds->setColorBright(video::SColor(event.cloud_params.color_bright));
+				clouds->setColorAmbient(video::SColor(event.cloud_params.color_ambient));
+				clouds->setHeight(event.cloud_params.height);
+				clouds->setThickness(event.cloud_params.thickness);
+				clouds->setSpeed(v2f(
+						event.cloud_params.speed_x,
+						event.cloud_params.speed_y));
+			}
+			break;
+
 		default:
 			// unknown or unhandled type
 			break;
diff --git a/src/network/clientopcodes.cpp b/src/network/clientopcodes.cpp
index 563baf77b..1be6e5522 100644
--- a/src/network/clientopcodes.cpp
+++ b/src/network/clientopcodes.cpp
@@ -108,7 +108,7 @@ const ToClientCommandHandler toClientCommandTable[TOCLIENT_NUM_MSG_TYPES] =
 	{ "TOCLIENT_LOCAL_PLAYER_ANIMATIONS",  TOCLIENT_STATE_CONNECTED, &Client::handleCommand_LocalPlayerAnimations }, // 0x51
 	{ "TOCLIENT_EYE_OFFSET",               TOCLIENT_STATE_CONNECTED, &Client::handleCommand_EyeOffset }, // 0x52
 	{ "TOCLIENT_DELETE_PARTICLESPAWNER",   TOCLIENT_STATE_CONNECTED, &Client::handleCommand_DeleteParticleSpawner }, // 0x53
-	null_command_handler,
+	{ "TOCLIENT_CLOUD_PARAMS",             TOCLIENT_STATE_CONNECTED, &Client::handleCommand_CloudParams }, // 0x54
 	null_command_handler,
 	null_command_handler,
 	null_command_handler,
diff --git a/src/network/clientpackethandler.cpp b/src/network/clientpackethandler.cpp
index 772ffe905..defc83f31 100644
--- a/src/network/clientpackethandler.cpp
+++ b/src/network/clientpackethandler.cpp
@@ -1168,6 +1168,34 @@ void Client::handleCommand_HudSetSky(NetworkPacket* pkt)
 	m_client_event_queue.push(event);
 }
 
+void Client::handleCommand_CloudParams(NetworkPacket* pkt)
+{
+	f32 density;
+	video::SColor color_bright;
+	video::SColor color_ambient;
+	f32 height;
+	f32 thickness;
+	v2f speed;
+
+	*pkt >> density >> color_bright >> color_ambient
+			>> height >> thickness >> speed;
+
+	ClientEvent event;
+	event.type                       = CE_CLOUD_PARAMS;
+	event.cloud_params.density       = density;
+	// use the underlying u32 representation, because we can't
+	// use struct members with constructors here, and this way
+	// we avoid using new() and delete() for no good reason
+	event.cloud_params.color_bright  = color_bright.color;
+	event.cloud_params.color_ambient = color_ambient.color;
+	event.cloud_params.height        = height;
+	event.cloud_params.thickness     = thickness;
+	// same here: deconstruct to skip constructor
+	event.cloud_params.speed_x       = speed.X;
+	event.cloud_params.speed_y       = speed.Y;
+	m_client_event_queue.push(event);
+}
+
 void Client::handleCommand_OverrideDayNightRatio(NetworkPacket* pkt)
 {
 	bool do_override;
diff --git a/src/network/networkprotocol.h b/src/network/networkprotocol.h
index e7a3469b7..a1a4f5bfa 100644
--- a/src/network/networkprotocol.h
+++ b/src/network/networkprotocol.h
@@ -610,6 +610,16 @@ enum ToClientCommand
 		u32 id
 	*/
 
+	TOCLIENT_CLOUD_PARAMS = 0x54,
+	/*
+		f1000 density
+		u8[4] color_diffuse (ARGB)
+		u8[4] color_ambient (ARGB)
+		f1000 height
+		f1000 thickness
+		v2f1000 speed
+	*/
+
 	TOCLIENT_SRP_BYTES_S_B = 0x60,
 	/*
 		Belonging to AUTH_MECHANISM_LEGACY_PASSWORD and AUTH_MECHANISM_SRP.
diff --git a/src/network/serveropcodes.cpp b/src/network/serveropcodes.cpp
index 31b571ff0..450730ca2 100644
--- a/src/network/serveropcodes.cpp
+++ b/src/network/serveropcodes.cpp
@@ -197,7 +197,7 @@ const ClientCommandFactory clientCommandFactoryTable[TOCLIENT_NUM_MSG_TYPES] =
 	{ "TOCLIENT_LOCAL_PLAYER_ANIMATIONS",  0, true }, // 0x51
 	{ "TOCLIENT_EYE_OFFSET",               0, true }, // 0x52
 	{ "TOCLIENT_DELETE_PARTICLESPAWNER",   0, true }, // 0x53
-	null_command_factory,
+	{ "TOCLIENT_CLOUD_PARAMS",             0, true }, // 0x54
 	null_command_factory,
 	null_command_factory,
 	null_command_factory,
diff --git a/src/remoteplayer.cpp b/src/remoteplayer.cpp
index 2dbfe9d9d..2b4db62f5 100644
--- a/src/remoteplayer.cpp
+++ b/src/remoteplayer.cpp
@@ -65,6 +65,14 @@ RemotePlayer::RemotePlayer(const char *name, IItemDefManager *idef):
 	movement_liquid_fluidity_smooth = g_settings->getFloat("movement_liquid_fluidity_smooth") * BS;
 	movement_liquid_sink            = g_settings->getFloat("movement_liquid_sink")            * BS;
 	movement_gravity                = g_settings->getFloat("movement_gravity")                * BS;
+
+	// copy defaults
+	m_cloud_params.density = 0.4f;
+	m_cloud_params.color_bright = video::SColor(255, 255, 240, 240);
+	m_cloud_params.color_ambient = video::SColor(255, 0, 0, 0);
+	m_cloud_params.height = 120.0f;
+	m_cloud_params.thickness = 16.0f;
+	m_cloud_params.speed = v2f(0.0f, -2.0f);
 }
 
 void RemotePlayer::serializeExtraAttributes(std::string &output)
diff --git a/src/remoteplayer.h b/src/remoteplayer.h
index 4b96835fc..b9d9c74f5 100644
--- a/src/remoteplayer.h
+++ b/src/remoteplayer.h
@@ -22,6 +22,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define REMOTEPLAYER_HEADER
 
 #include "player.h"
+#include "cloudparams.h"
 
 class PlayerSAO;
 
@@ -99,6 +100,16 @@ public:
 		*params = m_sky_params;
 	}
 
+	void setCloudParams(const CloudParams &cloud_params)
+	{
+		m_cloud_params = cloud_params;
+	}
+
+	const CloudParams &getCloudParams() const
+	{
+		return m_cloud_params;
+	}
+
 	bool checkModified() const { return m_dirty || inventory.checkModified(); }
 
 	void setModified(const bool x)
@@ -154,6 +165,7 @@ private:
 	std::string m_sky_type;
 	video::SColor m_sky_bgcolor;
 	std::vector<std::string> m_sky_params;
+	CloudParams m_cloud_params;
 };
 
 #endif
diff --git a/src/script/lua_api/l_object.cpp b/src/script/lua_api/l_object.cpp
index a5b6e3941..6cd852299 100644
--- a/src/script/lua_api/l_object.cpp
+++ b/src/script/lua_api/l_object.cpp
@@ -1729,6 +1729,85 @@ int ObjectRef::l_get_sky(lua_State *L)
 	return 3;
 }
 
+// set_clouds(self, {density=, color=, ambient=, height=, thickness=, speed=})
+int ObjectRef::l_set_clouds(lua_State *L)
+{
+	NO_MAP_LOCK_REQUIRED;
+	ObjectRef *ref = checkobject(L, 1);
+	RemotePlayer *player = getplayer(ref);
+	if (!player)
+		return 0;
+	if (!lua_istable(L, 2))
+		return 0;
+
+	CloudParams cloud_params = player->getCloudParams();
+
+	cloud_params.density = getfloatfield_default(L, 2, "density", cloud_params.density);
+
+	lua_getfield(L, 2, "color");
+	if (!lua_isnil(L, -1))
+		read_color(L, -1, &cloud_params.color_bright);
+	lua_pop(L, 1);
+	lua_getfield(L, 2, "ambient");
+	if (!lua_isnil(L, -1))
+		read_color(L, -1, &cloud_params.color_ambient);
+	lua_pop(L, 1);
+
+	cloud_params.height    = getfloatfield_default(L, 2, "height",    cloud_params.height   );
+	cloud_params.thickness = getfloatfield_default(L, 2, "thickness", cloud_params.thickness);
+
+	lua_getfield(L, 2, "speed");
+	if (lua_istable(L, -1)) {
+		v2f new_speed;
+		new_speed.X = getfloatfield_default(L, -1, "x", 0);
+		new_speed.Y = getfloatfield_default(L, -1, "y", 0);
+		cloud_params.speed = new_speed;
+	}
+	lua_pop(L, 1);
+
+	if (!getServer(L)->setClouds(player, cloud_params.density,
+			cloud_params.color_bright, cloud_params.color_ambient,
+			cloud_params.height, cloud_params.thickness,
+			cloud_params.speed))
+		return 0;
+
+	player->setCloudParams(cloud_params);
+
+	lua_pushboolean(L, true);
+	return 1;
+}
+
+int ObjectRef::l_get_clouds(lua_State *L)
+{
+	NO_MAP_LOCK_REQUIRED;
+	ObjectRef *ref = checkobject(L, 1);
+	RemotePlayer *player = getplayer(ref);
+	if (!player)
+		return 0;
+	const CloudParams &cloud_params = player->getCloudParams();
+
+	lua_newtable(L);
+	lua_pushnumber(L, cloud_params.density);
+	lua_setfield(L, -2, "density");
+	push_ARGB8(L, cloud_params.color_bright);
+	lua_setfield(L, -2, "color");
+	push_ARGB8(L, cloud_params.color_ambient);
+	lua_setfield(L, -2, "ambient");
+	lua_pushnumber(L, cloud_params.height);
+	lua_setfield(L, -2, "height");
+	lua_pushnumber(L, cloud_params.thickness);
+	lua_setfield(L, -2, "thickness");
+	lua_newtable(L);
+	lua_pushnumber(L, cloud_params.speed.X);
+	lua_setfield(L, -2, "x");
+	lua_pushnumber(L, cloud_params.speed.Y);
+	lua_setfield(L, -2, "y");
+	lua_setfield(L, -2, "speed");
+
+	return 1;
+}
+
+
 // override_day_night_ratio(self, brightness=0...1)
 int ObjectRef::l_override_day_night_ratio(lua_State *L)
 {
@@ -1911,6 +1990,8 @@ const luaL_Reg ObjectRef::methods[] = {
 	luamethod(ObjectRef, hud_get_hotbar_selected_image),
 	luamethod(ObjectRef, set_sky),
 	luamethod(ObjectRef, get_sky),
+	luamethod(ObjectRef, set_clouds),
+	luamethod(ObjectRef, get_clouds),
 	luamethod(ObjectRef, override_day_night_ratio),
 	luamethod(ObjectRef, get_day_night_ratio),
 	luamethod(ObjectRef, set_local_animation),
diff --git a/src/script/lua_api/l_object.h b/src/script/lua_api/l_object.h
index 98f5c2b11..0912a1c49 100644
--- a/src/script/lua_api/l_object.h
+++ b/src/script/lua_api/l_object.h
@@ -289,6 +289,12 @@ private:
 	// get_sky(self, type, list)
 	static int l_get_sky(lua_State *L);
 
+	// set_clouds(self, {density=, color=, ambient=, height=, thickness=, speed=})
+	static int l_set_clouds(lua_State *L);
+
+	// get_clouds(self)
+	static int l_get_clouds(lua_State *L);
+
 	// override_day_night_ratio(self, type)
 	static int l_override_day_night_ratio(lua_State *L);
 
diff --git a/src/server.cpp b/src/server.cpp
index 2edf83947..9ef69cb37 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -1882,6 +1882,20 @@ void Server::SendSetSky(u16 peer_id, const video::SColor &bgcolor,
 	Send(&pkt);
 }
 
+void Server::SendCloudParams(u16 peer_id, float density,
+		const video::SColor &color_bright,
+		const video::SColor &color_ambient,
+		float height,
+		float thickness,
+		const v2f &speed)
+{
+	NetworkPacket pkt(TOCLIENT_CLOUD_PARAMS, 0, peer_id);
+	pkt << density << color_bright << color_ambient
+			<< height << thickness << speed;
+
+	Send(&pkt);
+}
+
 void Server::SendOverrideDayNightRatio(u16 peer_id, bool do_override,
 		float ratio)
 {
@@ -3196,6 +3210,22 @@ bool Server::setSky(RemotePlayer *player, const video::SColor &bgcolor,
 	return true;
 }
 
+bool Server::setClouds(RemotePlayer *player, float density,
+	const video::SColor &color_bright,
+	const video::SColor &color_ambient,
+	float height,
+	float thickness,
+	const v2f &speed)
+{
+	if (!player)
+		return false;
+
+	SendCloudParams(player->peer_id, density,
+			color_bright, color_ambient, height,
+			thickness, speed);
+	return true;
+}
+
 bool Server::overrideDayNightRatio(RemotePlayer *player, bool do_override,
 	float ratio)
 {
diff --git a/src/server.h b/src/server.h
index 948fb8fc2..3a082b9a4 100644
--- a/src/server.h
+++ b/src/server.h
@@ -332,6 +332,12 @@ public:
 
 	bool setSky(RemotePlayer *player, const video::SColor &bgcolor,
 			const std::string &type, const std::vector<std::string> &params);
+	bool setClouds(RemotePlayer *player, float density,
+			const video::SColor &color_bright,
+			const video::SColor &color_ambient,
+			float height,
+			float thickness,
+			const v2f &speed);
 
 	bool overrideDayNightRatio(RemotePlayer *player, bool do_override, float brightness);
 
@@ -401,6 +407,12 @@ private:
 	void SendHUDSetParam(u16 peer_id, u16 param, const std::string &value);
 	void SendSetSky(u16 peer_id, const video::SColor &bgcolor,
 			const std::string &type, const std::vector<std::string> &params);
+	void SendCloudParams(u16 peer_id, float density,
+			const video::SColor &color_bright,
+			const video::SColor &color_ambient,
+			float height,
+			float thickness,
+			const v2f &speed);
 	void SendOverrideDayNightRatio(u16 peer_id, bool do_override, float ratio);
 
 	/*
diff --git a/src/sky.cpp b/src/sky.cpp
index 211a2dcdc..7f999feb0 100644
--- a/src/sky.cpp
+++ b/src/sky.cpp
@@ -534,8 +534,10 @@ void Sky::update(float time_of_day, float time_brightness,
 	video::SColorf skycolor_bright_dawn_f = video::SColor(255, 180, 186, 250);
 	video::SColorf skycolor_bright_night_f = video::SColor(255, 0, 107, 255);
 	
-	video::SColorf cloudcolor_bright_normal_f = video::SColor(255, 240, 240, 255);
-	video::SColorf cloudcolor_bright_dawn_f = video::SColor(255, 255, 223, 191);
+	// pure white: becomes "diffuse light component" for clouds
+	video::SColorf cloudcolor_bright_normal_f = video::SColor(255, 255, 255, 255);
+	// dawn-factoring version of pure white (note: R is above 1.0)
+	video::SColorf cloudcolor_bright_dawn_f(255.0f/240.0f, 223.0f/240.0f, 191.0f/255.0f);
 
 	float cloud_color_change_fraction = 0.95;
 	if (sunlight_seen) {