Rewrite rendering engine (#6253)

* Clean draw_*() arguments

* Split rendering core

* Add anaglyph 3D

* Interlaced 3D

* Drop obsolete methods

19 files changed, 960 insertions, 613 deletions

diff --git a/src/client/CMakeLists.txt b/src/client/CMakeLists.txt
index 4ba8fea5b..3cc6c0351 100644
--- a/src/client/CMakeLists.txt
+++ b/src/client/CMakeLists.txt
@@ -1,4 +1,12 @@
 set(client_SRCS
+	${CMAKE_CURRENT_SOURCE_DIR}/render/anaglyph.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/core.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/factory.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/interlaced.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/pageflip.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/plain.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/sidebyside.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/render/stereo.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/renderingengine.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/clientlauncher.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/inputhandler.cpp
@@ -6,4 +14,3 @@ set(client_SRCS
 	${CMAKE_CURRENT_SOURCE_DIR}/joystick_controller.cpp
 	PARENT_SCOPE
 )
-
diff --git a/src/client/render/anaglyph.cpp b/src/client/render/anaglyph.cpp
new file mode 100644
index 000000000..1fad9e8d3
--- /dev/null
+++ b/src/client/render/anaglyph.cpp
@@ -0,0 +1,51 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "anaglyph.h"
+
+void RenderingCoreAnaglyph::drawAll()
+{
+	renderBothImages();
+	drawPostFx();
+	drawHUD();
+}
+
+void RenderingCoreAnaglyph::setupMaterial(int color_mask)
+{
+	video::SOverrideMaterial &mat = driver->getOverrideMaterial();
+	mat.Material.ColorMask = color_mask;
+	mat.EnableFlags = video::EMF_COLOR_MASK;
+	mat.EnablePasses = scene::ESNRP_SKY_BOX | scene::ESNRP_SOLID |
+			   scene::ESNRP_TRANSPARENT | scene::ESNRP_TRANSPARENT_EFFECT |
+			   scene::ESNRP_SHADOW;
+}
+
+void RenderingCoreAnaglyph::useEye(bool right)
+{
+	RenderingCoreStereo::useEye(right);
+	driver->clearZBuffer();
+	setupMaterial(right ? video::ECP_GREEN | video::ECP_BLUE : video::ECP_RED);
+}
+
+void RenderingCoreAnaglyph::resetEye()
+{
+	setupMaterial(video::ECP_ALL);
+	RenderingCoreStereo::resetEye();
+}
diff --git a/src/client/render/anaglyph.h b/src/client/render/anaglyph.h
new file mode 100644
index 000000000..6305efb90
--- /dev/null
+++ b/src/client/render/anaglyph.h
@@ -0,0 +1,34 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "stereo.h"
+
+class RenderingCoreAnaglyph : public RenderingCoreStereo
+{
+protected:
+	void setupMaterial(int color_mask);
+	void useEye(bool right) override;
+	void resetEye() override;
+
+public:
+	using RenderingCoreStereo::RenderingCoreStereo;
+	void drawAll() override;
+};
diff --git a/src/client/render/core.cpp b/src/client/render/core.cpp
new file mode 100644
index 000000000..7a4230c84
--- /dev/null
+++ b/src/client/render/core.cpp
@@ -0,0 +1,101 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "core.h"
+#include "camera.h"
+#include "client.h"
+#include "clientmap.h"
+#include "hud.h"
+#include "minimap.h"
+
+RenderingCore::RenderingCore(IrrlichtDevice *_device, Client *_client, Hud *_hud)
+    : device(_device), driver(device->getVideoDriver()), smgr(device->getSceneManager()),
+      guienv(device->getGUIEnvironment()), client(_client), camera(client->getCamera()),
+      mapper(client->getMinimap()), hud(_hud)
+{
+	screensize = driver->getScreenSize();
+	virtual_size = screensize;
+}
+
+RenderingCore::~RenderingCore()
+{
+	clearTextures();
+}
+
+void RenderingCore::initialize()
+{
+	// have to be called late as the VMT is not ready in the constructor:
+	initTextures();
+}
+
+void RenderingCore::updateScreenSize()
+{
+	virtual_size = screensize;
+	clearTextures();
+	initTextures();
+}
+
+void RenderingCore::draw(video::SColor _skycolor, bool _show_hud, bool _show_minimap,
+		bool _draw_wield_tool, bool _draw_crosshair)
+{
+	v2u32 ss = driver->getScreenSize();
+	if (screensize != ss) {
+		screensize = ss;
+		updateScreenSize();
+	}
+	skycolor = _skycolor;
+	show_hud = _show_hud;
+	show_minimap = _show_minimap;
+	draw_wield_tool = _draw_wield_tool;
+	draw_crosshair = _draw_crosshair;
+
+	beforeDraw();
+	drawAll();
+}
+
+void RenderingCore::draw3D()
+{
+	smgr->drawAll();
+	driver->setTransform(video::ETS_WORLD, core::IdentityMatrix);
+	if (!show_hud)
+		return;
+	hud->drawSelectionMesh();
+	if (draw_wield_tool)
+		camera->drawWieldedTool();
+}
+
+void RenderingCore::drawHUD()
+{
+	if (show_hud) {
+		if (draw_crosshair)
+			hud->drawCrosshair();
+		hud->drawHotbar(client->getPlayerItem());
+		hud->drawLuaElements(camera->getOffset());
+		camera->drawNametags();
+		if (mapper && show_minimap)
+			mapper->drawMinimap();
+	}
+	guienv->drawAll();
+}
+
+void RenderingCore::drawPostFx()
+{
+	client->getEnv().getClientMap().renderPostFx(camera->getCameraMode());
+}
diff --git a/src/client/render/core.h b/src/client/render/core.h
new file mode 100644
index 000000000..35def7f20
--- /dev/null
+++ b/src/client/render/core.h
@@ -0,0 +1,75 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "irrlichttypes_extrabloated.h"
+
+class Camera;
+class Client;
+class Hud;
+class Minimap;
+
+class RenderingCore
+{
+protected:
+	v2u32 screensize;
+	v2u32 virtual_size;
+	video::SColor skycolor;
+	bool show_hud;
+	bool show_minimap;
+	bool draw_wield_tool;
+	bool draw_crosshair;
+
+	IrrlichtDevice *device;
+	video::IVideoDriver *driver;
+	scene::ISceneManager *smgr;
+	gui::IGUIEnvironment *guienv;
+
+	Client *client;
+	Camera *camera;
+	Minimap *mapper;
+	Hud *hud;
+
+	void updateScreenSize();
+	virtual void initTextures() {}
+	virtual void clearTextures() {}
+
+	virtual void beforeDraw() {}
+	virtual void drawAll() = 0;
+
+	void draw3D();
+	void drawHUD();
+	void drawPostFx();
+
+public:
+	RenderingCore(IrrlichtDevice *_device, Client *_client, Hud *_hud);
+	RenderingCore(const RenderingCore &) = delete;
+	RenderingCore(RenderingCore &&) = delete;
+	virtual ~RenderingCore();
+
+	RenderingCore &operator=(const RenderingCore &) = delete;
+	RenderingCore &operator=(RenderingCore &&) = delete;
+
+	void initialize();
+	void draw(video::SColor _skycolor, bool _show_hud, bool _show_minimap,
+			bool _draw_wield_tool, bool _draw_crosshair);
+
+	inline v2u32 getVirtualSize() const { return virtual_size; }
+};
diff --git a/src/client/render/factory.cpp b/src/client/render/factory.cpp
new file mode 100644
index 000000000..c2c3f341e
--- /dev/null
+++ b/src/client/render/factory.cpp
@@ -0,0 +1,45 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "factory.h"
+#include <stdexcept>
+#include "plain.h"
+#include "anaglyph.h"
+#include "interlaced.h"
+#include "pageflip.h"
+#include "sidebyside.h"
+
+RenderingCore *createRenderingCore(const std::string &stereo_mode, IrrlichtDevice *device,
+		Client *client, Hud *hud)
+{
+	if (stereo_mode == "none")
+		return new RenderingCorePlain(device, client, hud);
+	if (stereo_mode == "anaglyph")
+		return new RenderingCoreAnaglyph(device, client, hud);
+	if (stereo_mode == "interlaced")
+		return new RenderingCoreInterlaced(device, client, hud);
+	if (stereo_mode == "pageflip")
+		return new RenderingCorePageflip(device, client, hud);
+	if (stereo_mode == "sidebyside")
+		return new RenderingCoreSideBySide(device, client, hud);
+	if (stereo_mode == "topbottom")
+		return new RenderingCoreSideBySide(device, client, hud, true);
+	throw std::invalid_argument("Invalid rendering mode: " + stereo_mode);
+}
diff --git a/src/client/render/factory.h b/src/client/render/factory.h
new file mode 100644
index 000000000..c7c5cdc1e
--- /dev/null
+++ b/src/client/render/factory.h
@@ -0,0 +1,25 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include <string>
+#include "core.h"
+
+RenderingCore *createRenderingCore(const std::string &stereo_mode, IrrlichtDevice *device,
+		Client *client, Hud *hud);
diff --git a/src/client/render/interlaced.cpp b/src/client/render/interlaced.cpp
new file mode 100644
index 000000000..ccd4e60cf
--- /dev/null
+++ b/src/client/render/interlaced.cpp
@@ -0,0 +1,116 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "interlaced.h"
+#include "client.h"
+#include "shader.h"
+#include "client/tile.h"
+
+RenderingCoreInterlaced::RenderingCoreInterlaced(
+		IrrlichtDevice *_device, Client *_client, Hud *_hud)
+    : RenderingCoreStereo(_device, _client, _hud)
+{
+	initMaterial();
+}
+
+void RenderingCoreInterlaced::initMaterial()
+{
+	IShaderSource *s = client->getShaderSource();
+	mat.UseMipMaps = false;
+	mat.ZBuffer = false;
+	mat.ZWriteEnable = false;
+	u32 shader = s->getShader("3d_interlaced_merge", TILE_MATERIAL_BASIC, 0);
+	mat.MaterialType = s->getShaderInfo(shader).material;
+	for (int k = 0; k < 3; ++k) {
+		mat.TextureLayer[k].AnisotropicFilter = false;
+		mat.TextureLayer[k].BilinearFilter = false;
+		mat.TextureLayer[k].TrilinearFilter = false;
+		mat.TextureLayer[k].TextureWrapU = video::ETC_CLAMP_TO_EDGE;
+		mat.TextureLayer[k].TextureWrapV = video::ETC_CLAMP_TO_EDGE;
+	}
+}
+
+void RenderingCoreInterlaced::initTextures()
+{
+	v2u32 image_size{screensize.X, screensize.Y / 2};
+	left = driver->addRenderTargetTexture(
+			image_size, "3d_render_left", video::ECF_A8R8G8B8);
+	right = driver->addRenderTargetTexture(
+			image_size, "3d_render_right", video::ECF_A8R8G8B8);
+	mask = driver->addTexture(screensize, "3d_render_mask", video::ECF_A8R8G8B8);
+	initMask();
+	mat.TextureLayer[0].Texture = left;
+	mat.TextureLayer[1].Texture = right;
+	mat.TextureLayer[2].Texture = mask;
+}
+
+void RenderingCoreInterlaced::clearTextures()
+{
+	driver->removeTexture(left);
+	driver->removeTexture(right);
+	driver->removeTexture(mask);
+}
+
+void RenderingCoreInterlaced::initMask()
+{
+	u8 *data = reinterpret_cast<u8 *>(mask->lock());
+	for (u32 j = 0; j < screensize.Y; j++) {
+		u8 val = j % 2 ? 0xff : 0x00;
+		memset(data, val, 4 * screensize.X);
+		data += 4 * screensize.X;
+	}
+	mask->unlock();
+}
+
+void RenderingCoreInterlaced::drawAll()
+{
+	renderBothImages();
+	merge();
+	drawHUD();
+}
+
+void RenderingCoreInterlaced::merge()
+{
+	static const video::S3DVertex vertices[4] = {
+			video::S3DVertex(1.0, -1.0, 0.0, 0.0, 0.0, -1.0,
+					video::SColor(255, 0, 255, 255), 1.0, 0.0),
+			video::S3DVertex(-1.0, -1.0, 0.0, 0.0, 0.0, -1.0,
+					video::SColor(255, 255, 0, 255), 0.0, 0.0),
+			video::S3DVertex(-1.0, 1.0, 0.0, 0.0, 0.0, -1.0,
+					video::SColor(255, 255, 255, 0), 0.0, 1.0),
+			video::S3DVertex(1.0, 1.0, 0.0, 0.0, 0.0, -1.0,
+					video::SColor(255, 255, 255, 255), 1.0, 1.0),
+	};
+	static const u16 indices[6] = {0, 1, 2, 2, 3, 0};
+	driver->setMaterial(mat);
+	driver->drawVertexPrimitiveList(&vertices, 4, &indices, 2);
+}
+
+void RenderingCoreInterlaced::useEye(bool _right)
+{
+	driver->setRenderTarget(_right ? right : left, true, true, skycolor);
+	RenderingCoreStereo::useEye(_right);
+}
+
+void RenderingCoreInterlaced::resetEye()
+{
+	driver->setRenderTarget(nullptr, false, false, skycolor);
+	RenderingCoreStereo::resetEye();
+}
diff --git a/src/client/render/interlaced.h b/src/client/render/interlaced.h
new file mode 100644
index 000000000..d0c1d9e62
--- /dev/null
+++ b/src/client/render/interlaced.h
@@ -0,0 +1,43 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "stereo.h"
+
+class RenderingCoreInterlaced : public RenderingCoreStereo
+{
+protected:
+	video::ITexture *left = nullptr;
+	video::ITexture *right = nullptr;
+	video::ITexture *mask = nullptr;
+	video::SMaterial mat;
+
+	void initMaterial();
+	void initTextures() override;
+	void clearTextures() override;
+	void initMask();
+	void useEye(bool right) override;
+	void resetEye() override;
+	void merge();
+
+public:
+	RenderingCoreInterlaced(IrrlichtDevice *_device, Client *_client, Hud *_hud);
+	void drawAll() override;
+};
diff --git a/src/client/render/pageflip.cpp b/src/client/render/pageflip.cpp
new file mode 100644
index 000000000..8d6fa7423
--- /dev/null
+++ b/src/client/render/pageflip.cpp
@@ -0,0 +1,55 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "pageflip.h"
+
+void RenderingCorePageflip::initTextures()
+{
+	hud = driver->addRenderTargetTexture(
+			screensize, "3d_render_hud", video::ECF_A8R8G8B8);
+}
+
+void RenderingCorePageflip::clearTextures()
+{
+	driver->removeTexture(hud);
+}
+
+void RenderingCorePageflip::drawAll()
+{
+	driver->setRenderTarget(hud, true, true, video::SColor(0, 0, 0, 0));
+	drawHUD();
+	driver->setRenderTarget(nullptr, false, false, skycolor);
+	renderBothImages();
+}
+
+void RenderingCorePageflip::useEye(bool _right)
+{
+	driver->setRenderTarget(_right ? video::ERT_STEREO_RIGHT_BUFFER
+				       : video::ERT_STEREO_LEFT_BUFFER,
+			true, true, skycolor);
+	RenderingCoreStereo::useEye(_right);
+}
+
+void RenderingCorePageflip::resetEye()
+{
+	driver->draw2DImage(hud, v2s32(0, 0));
+	driver->setRenderTarget(video::ERT_FRAME_BUFFER, false, false, skycolor);
+	RenderingCoreStereo::resetEye();
+}
diff --git a/src/client/render/pageflip.h b/src/client/render/pageflip.h
new file mode 100644
index 000000000..ee4567ac4
--- /dev/null
+++ b/src/client/render/pageflip.h
@@ -0,0 +1,37 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "stereo.h"
+
+class RenderingCorePageflip : public RenderingCoreStereo
+{
+protected:
+	video::ITexture *hud = nullptr;
+
+	void initTextures() override;
+	void clearTextures() override;
+	void useEye(bool right) override;
+	void resetEye() override;
+
+public:
+	using RenderingCoreStereo::RenderingCoreStereo;
+	void drawAll() override;
+};
diff --git a/src/client/render/plain.cpp b/src/client/render/plain.cpp
new file mode 100644
index 000000000..94921245b
--- /dev/null
+++ b/src/client/render/plain.cpp
@@ -0,0 +1,76 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "plain.h"
+#include "settings.h"
+
+inline u32 scaledown(u32 coef, u32 size)
+{
+	return (size + coef - 1) / coef;
+}
+
+RenderingCorePlain::RenderingCorePlain(
+		IrrlichtDevice *_device, Client *_client, Hud *_hud)
+    : RenderingCore(_device, _client, _hud)
+{
+	scale = g_settings->getU16("undersampling");
+}
+
+void RenderingCorePlain::initTextures()
+{
+	if (!scale)
+		return;
+	v2u32 size{scaledown(scale, screensize.X), scaledown(scale, screensize.Y)};
+	lowres = driver->addRenderTargetTexture(
+			size, "render_lowres", video::ECF_A8R8G8B8);
+}
+
+void RenderingCorePlain::clearTextures()
+{
+	if (!scale)
+		return;
+	driver->removeTexture(lowres);
+}
+
+void RenderingCorePlain::beforeDraw()
+{
+	if (!scale)
+		return;
+	driver->setRenderTarget(lowres, true, true, skycolor);
+}
+
+void RenderingCorePlain::upscale()
+{
+	if (!scale)
+		return;
+	driver->setRenderTarget(0, true, true);
+	v2u32 size{scaledown(scale, screensize.X), scaledown(scale, screensize.Y)};
+	v2u32 dest_size{scale * size.X, scale * size.Y};
+	driver->draw2DImage(lowres, core::rect<s32>(0, 0, dest_size.X, dest_size.Y),
+			core::rect<s32>(0, 0, size.X, size.Y));
+}
+
+void RenderingCorePlain::drawAll()
+{
+	draw3D();
+	drawPostFx();
+	upscale();
+	drawHUD();
+}
diff --git a/src/client/render/plain.h b/src/client/render/plain.h
new file mode 100644
index 000000000..af9d7036b
--- /dev/null
+++ b/src/client/render/plain.h
@@ -0,0 +1,38 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "core.h"
+
+class RenderingCorePlain : public RenderingCore
+{
+protected:
+	int scale = 0;
+	video::ITexture *lowres = nullptr;
+
+	void initTextures() override;
+	void clearTextures() override;
+	void beforeDraw() override;
+	void upscale();
+
+public:
+	RenderingCorePlain(IrrlichtDevice *_device, Client *_client, Hud *_hud);
+	void drawAll() override;
+};
diff --git a/src/client/render/sidebyside.cpp b/src/client/render/sidebyside.cpp
new file mode 100644
index 000000000..2af09ee33
--- /dev/null
+++ b/src/client/render/sidebyside.cpp
@@ -0,0 +1,74 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "sidebyside.h"
+#include <ICameraSceneNode.h>
+#include "hud.h"
+
+RenderingCoreSideBySide::RenderingCoreSideBySide(
+		IrrlichtDevice *_device, Client *_client, Hud *_hud, bool _horizontal)
+    : RenderingCoreStereo(_device, _client, _hud), horizontal(_horizontal)
+{
+}
+
+void RenderingCoreSideBySide::initTextures()
+{
+	if (horizontal) {
+		image_size = {screensize.X, screensize.Y / 2};
+		rpos = v2s32(0, screensize.Y / 2);
+	} else {
+		image_size = {screensize.X / 2, screensize.Y};
+		rpos = v2s32(screensize.X / 2, 0);
+	}
+	virtual_size = image_size;
+	left = driver->addRenderTargetTexture(
+			image_size, "3d_render_left", video::ECF_A8R8G8B8);
+	right = driver->addRenderTargetTexture(
+			image_size, "3d_render_right", video::ECF_A8R8G8B8);
+}
+
+void RenderingCoreSideBySide::clearTextures()
+{
+	driver->removeTexture(left);
+	driver->removeTexture(right);
+}
+
+void RenderingCoreSideBySide::drawAll()
+{
+	driver->OnResize(image_size); // HACK to make GUI smaller
+	renderBothImages();
+	driver->OnResize(screensize);
+	driver->draw2DImage(left, {});
+	driver->draw2DImage(right, rpos);
+}
+
+void RenderingCoreSideBySide::useEye(bool _right)
+{
+	driver->setRenderTarget(_right ? right : left, true, true, skycolor);
+	RenderingCoreStereo::useEye(_right);
+}
+
+void RenderingCoreSideBySide::resetEye()
+{
+	hud->resizeHotbar();
+	drawHUD();
+	driver->setRenderTarget(nullptr, false, false, skycolor);
+	RenderingCoreStereo::resetEye();
+}
diff --git a/src/client/render/sidebyside.h b/src/client/render/sidebyside.h
new file mode 100644
index 000000000..70b2bdcf5
--- /dev/null
+++ b/src/client/render/sidebyside.h
@@ -0,0 +1,42 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "stereo.h"
+
+class RenderingCoreSideBySide : public RenderingCoreStereo
+{
+protected:
+	video::ITexture *left = nullptr;
+	video::ITexture *right = nullptr;
+	bool horizontal = false;
+	core::dimension2du image_size;
+	v2s32 rpos;
+
+	void initTextures() override;
+	void clearTextures() override;
+	void useEye(bool right) override;
+	void resetEye() override;
+
+public:
+	RenderingCoreSideBySide(IrrlichtDevice *_device, Client *_client, Hud *_hud,
+			bool _horizontal = false);
+	void drawAll() override;
+};
diff --git a/src/client/render/stereo.cpp b/src/client/render/stereo.cpp
new file mode 100644
index 000000000..eec9f8ced
--- /dev/null
+++ b/src/client/render/stereo.cpp
@@ -0,0 +1,60 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#include "stereo.h"
+#include "camera.h"
+#include "constants.h"
+#include "settings.h"
+
+RenderingCoreStereo::RenderingCoreStereo(
+		IrrlichtDevice *_device, Client *_client, Hud *_hud)
+    : RenderingCore(_device, _client, _hud)
+{
+	eye_offset = BS * g_settings->getFloat("3d_paralax_strength");
+}
+
+void RenderingCoreStereo::beforeDraw()
+{
+	cam = camera->getCameraNode();
+	base_transform = cam->getRelativeTransformation();
+}
+
+void RenderingCoreStereo::useEye(bool right)
+{
+	core::matrix4 move;
+	move.setTranslation(
+			core::vector3df(right ? eye_offset : -eye_offset, 0.0f, 0.0f));
+	cam->setPosition((base_transform * move).getTranslation());
+}
+
+void RenderingCoreStereo::resetEye()
+{
+	cam->setPosition(base_transform.getTranslation());
+}
+
+void RenderingCoreStereo::renderBothImages()
+{
+	useEye(false);
+	draw3D();
+	resetEye();
+	useEye(true);
+	draw3D();
+	resetEye();
+}
diff --git a/src/client/render/stereo.h b/src/client/render/stereo.h
new file mode 100644
index 000000000..0b13de376
--- /dev/null
+++ b/src/client/render/stereo.h
@@ -0,0 +1,38 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 numzero, Lobachesky Vitaly <numzer0@yandex.ru>
+
+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.
+*/
+
+#pragma once
+#include "core.h"
+
+class RenderingCoreStereo : public RenderingCore
+{
+protected:
+	scene::ICameraSceneNode *cam;
+	core::matrix4 base_transform;
+	float eye_offset;
+
+	void beforeDraw() override;
+	virtual void useEye(bool right);
+	virtual void resetEye();
+	void renderBothImages();
+
+public:
+	RenderingCoreStereo(IrrlichtDevice *_device, Client *_client, Hud *_hud);
+};
diff --git a/src/client/renderingengine.cpp b/src/client/renderingengine.cpp
index a57388596..f9da178b9 100644
--- a/src/client/renderingengine.cpp
+++ b/src/client/renderingengine.cpp
@@ -31,6 +31,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "minimap.h"
 #include "clientmap.h"
 #include "renderingengine.h"
+#include "render/core.h"
+#include "render/factory.h"
 #include "inputhandler.h"
 #include "gettext.h"
 
@@ -102,17 +104,22 @@ RenderingEngine::RenderingEngine(IEventReceiver *receiver)
 #endif
 
 	m_device = createDeviceEx(params);
+	driver = m_device->getVideoDriver();
+
 	s_singleton = this;
 }
 
 RenderingEngine::~RenderingEngine()
 {
+	core.reset();
 	m_device->drop();
 	s_singleton = nullptr;
 }
 
 v2u32 RenderingEngine::getWindowSize() const
 {
+	if (core)
+		return core->getVirtualSize();
 	return m_device->getVideoDriver()->getScreenSize();
 }
 
@@ -121,11 +128,6 @@ void RenderingEngine::setResizable(bool resize)
 	m_device->setResizable(resize);
 }
 
-video::IVideoDriver *RenderingEngine::getVideoDriver()
-{
-	return m_device->getVideoDriver();
-}
-
 bool RenderingEngine::print_video_modes()
 {
 	IrrlichtDevice *nulldevice;
@@ -213,11 +215,10 @@ bool RenderingEngine::setWindowIcon()
 							       "-xorg-icon-128.png");
 #endif
 #elif defined(_WIN32)
-	const video::SExposedVideoData exposedData =
-			m_device->getVideoDriver()->getExposedVideoData();
+	const video::SExposedVideoData exposedData = driver->getExposedVideoData();
 	HWND hWnd; // Window handle
 
-	switch (m_device->getVideoDriver()->getDriverType()) {
+	switch (driver->getDriverType()) {
 	case video::EDT_DIRECT3D8:
 		hWnd = reinterpret_cast<HWND>(exposedData.D3D8.HWnd);
 		break;
@@ -253,14 +254,12 @@ bool RenderingEngine::setXorgWindowIconFromPath(const std::string &icon_file)
 {
 #ifdef XORG_USED
 
-	video::IVideoDriver *v_driver = m_device->getVideoDriver();
-
 	video::IImageLoader *image_loader = NULL;
-	u32 cnt = v_driver->getImageLoaderCount();
+	u32 cnt = driver->getImageLoaderCount();
 	for (u32 i = 0; i < cnt; i++) {
-		if (v_driver->getImageLoader(i)->isALoadableFileExtension(
+		if (driver->getImageLoader(i)->isALoadableFileExtension(
 				    icon_file.c_str())) {
-			image_loader = v_driver->getImageLoader(i);
+			image_loader = driver->getImageLoader(i);
 			break;
 		}
 	}
@@ -313,7 +312,7 @@ bool RenderingEngine::setXorgWindowIconFromPath(const std::string &icon_file)
 	img->drop();
 	icon_f->drop();
 
-	const video::SExposedVideoData &video_data = v_driver->getExposedVideoData();
+	const video::SExposedVideoData &video_data = driver->getExposedVideoData();
 
 	Display *x11_dpl = (Display *)video_data.OpenGLLinux.X11Display;
 
@@ -442,558 +441,22 @@ std::vector<irr::video::E_DRIVER_TYPE> RenderingEngine::getSupportedVideoDrivers
 	return drivers;
 }
 
-void RenderingEngine::_draw_scene(Camera *camera, Client *client, LocalPlayer *player,
-		Hud *hud, Minimap *mapper, gui::IGUIEnvironment *guienv,
-		const v2u32 &screensize, const video::SColor &skycolor, bool show_hud,
-		bool show_minimap)
+void RenderingEngine::_initialize(Client *client, Hud *hud)
 {
-	bool draw_wield_tool =
-			(show_hud && (player->hud_flags & HUD_FLAG_WIELDITEM_VISIBLE) &&
-					camera->getCameraMode() < CAMERA_MODE_THIRD);
-
-	bool draw_crosshair = ((player->hud_flags & HUD_FLAG_CROSSHAIR_VISIBLE) &&
-			       (camera->getCameraMode() != CAMERA_MODE_THIRD_FRONT));
-
-#ifdef HAVE_TOUCHSCREENGUI
-	try {
-		draw_crosshair = !g_settings->getBool("touchtarget");
-	} catch (SettingNotFoundException) {
-	}
-#endif
-
 	const std::string &draw_mode = g_settings->get("3d_mode");
-
-	if (draw_mode == "anaglyph") {
-		draw_anaglyph_3d_mode(
-				camera, show_hud, hud, draw_wield_tool, client, guienv);
-		draw_crosshair = false;
-	} else if (draw_mode == "interlaced") {
-		draw_interlaced_3d_mode(camera, show_hud, hud, screensize,
-				draw_wield_tool, client, guienv, skycolor);
-		draw_crosshair = false;
-	} else if (draw_mode == "sidebyside") {
-		draw_sidebyside_3d_mode(camera, show_hud, hud, screensize,
-				draw_wield_tool, client, guienv, skycolor);
-		show_hud = false;
-	} else if (draw_mode == "topbottom") {
-		draw_top_bottom_3d_mode(camera, show_hud, hud, screensize,
-				draw_wield_tool, client, guienv, skycolor);
-		show_hud = false;
-	} else if (draw_mode == "pageflip") {
-		draw_pageflip_3d_mode(camera, show_hud, hud, screensize, draw_wield_tool,
-				client, guienv, skycolor);
-		draw_crosshair = false;
-		show_hud = false;
-	} else {
-		draw_plain(camera, show_hud, hud, screensize, draw_wield_tool, client,
-				guienv, skycolor);
-	}
-
-	/*
-		Post effects
-	*/
-	client->getEnv().getClientMap().renderPostFx(camera->getCameraMode());
-
-	// TODO how to make those 3d too
-	if (show_hud) {
-		if (draw_crosshair)
-			hud->drawCrosshair();
-
-		hud->drawHotbar(client->getPlayerItem());
-		hud->drawLuaElements(camera->getOffset());
-		camera->drawNametags();
-
-		if (mapper && show_minimap)
-			mapper->drawMinimap();
-	}
-
-	guienv->drawAll();
+	core.reset(createRenderingCore(draw_mode, m_device, client, hud));
+	core->initialize();
 }
 
-void RenderingEngine::draw_anaglyph_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-		bool draw_wield_tool, Client *client, gui::IGUIEnvironment *guienv)
+void RenderingEngine::_finalize()
 {
-
-	/* preserve old setup*/
-	irr::core::vector3df oldPosition = camera->getCameraNode()->getPosition();
-	irr::core::vector3df oldTarget = camera->getCameraNode()->getTarget();
-
-	irr::core::matrix4 startMatrix =
-			camera->getCameraNode()->getAbsoluteTransformation();
-	irr::core::vector3df focusPoint =
-			(camera->getCameraNode()->getTarget() -
-					camera->getCameraNode()->getAbsolutePosition())
-					.setLength(1) +
-			camera->getCameraNode()->getAbsolutePosition();
-
-	// Left eye...
-	irr::core::vector3df leftEye;
-	irr::core::matrix4 leftMove;
-	leftMove.setTranslation(irr::core::vector3df(
-			-g_settings->getFloat("3d_paralax_strength"), 0.0f, 0.0f));
-	leftEye = (startMatrix * leftMove).getTranslation();
-
-	// clear the depth buffer, and color
-	getVideoDriver()->beginScene(true, true, irr::video::SColor(0, 200, 200, 255));
-	getVideoDriver()->getOverrideMaterial().Material.ColorMask = irr::video::ECP_RED;
-	getVideoDriver()->getOverrideMaterial().EnableFlags = irr::video::EMF_COLOR_MASK;
-	getVideoDriver()->getOverrideMaterial().EnablePasses =
-			irr::scene::ESNRP_SKY_BOX + irr::scene::ESNRP_SOLID +
-			irr::scene::ESNRP_TRANSPARENT +
-			irr::scene::ESNRP_TRANSPARENT_EFFECT + irr::scene::ESNRP_SHADOW;
-	camera->getCameraNode()->setPosition(leftEye);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&leftMove);
-	}
-
-	guienv->drawAll();
-
-	// Right eye...
-	irr::core::vector3df rightEye;
-	irr::core::matrix4 rightMove;
-	rightMove.setTranslation(irr::core::vector3df(
-			g_settings->getFloat("3d_paralax_strength"), 0.0f, 0.0f));
-	rightEye = (startMatrix * rightMove).getTranslation();
-
-	// clear the depth buffer
-	getVideoDriver()->clearZBuffer();
-	getVideoDriver()->getOverrideMaterial().Material.ColorMask =
-			irr::video::ECP_GREEN + irr::video::ECP_BLUE;
-	getVideoDriver()->getOverrideMaterial().EnableFlags = irr::video::EMF_COLOR_MASK;
-	getVideoDriver()->getOverrideMaterial().EnablePasses =
-			irr::scene::ESNRP_SKY_BOX + irr::scene::ESNRP_SOLID +
-			irr::scene::ESNRP_TRANSPARENT +
-			irr::scene::ESNRP_TRANSPARENT_EFFECT + irr::scene::ESNRP_SHADOW;
-	camera->getCameraNode()->setPosition(rightEye);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&rightMove);
-	}
-
-	guienv->drawAll();
-
-	getVideoDriver()->getOverrideMaterial().Material.ColorMask = irr::video::ECP_ALL;
-	getVideoDriver()->getOverrideMaterial().EnableFlags = 0;
-	getVideoDriver()->getOverrideMaterial().EnablePasses = 0;
-	camera->getCameraNode()->setPosition(oldPosition);
-	camera->getCameraNode()->setTarget(oldTarget);
-}
-
-void RenderingEngine::init_texture(
-		const v2u32 &screensize, video::ITexture **texture, const char *name)
-{
-	if (*texture) {
-		getVideoDriver()->removeTexture(*texture);
-	}
-	*texture = getVideoDriver()->addRenderTargetTexture(
-			core::dimension2d<u32>(screensize.X, screensize.Y), name,
-			irr::video::ECF_A8R8G8B8);
-}
-
-video::ITexture *RenderingEngine::draw_image(const v2u32 &screensize, parallax_sign psign,
-		const irr::core::matrix4 &startMatrix,
-		const irr::core::vector3df &focusPoint, bool show_hud, Camera *camera,
-		Hud *hud, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-	static video::ITexture *images[2] = {NULL, NULL};
-	static v2u32 last_screensize = v2u32(0, 0);
-
-	video::ITexture *image = NULL;
-
-	if (screensize != last_screensize) {
-		init_texture(screensize, &images[1], "mt_drawimage_img1");
-		init_texture(screensize, &images[0], "mt_drawimage_img2");
-		last_screensize = screensize;
-	}
-
-	if (psign == RIGHT)
-		image = images[1];
-	else
-		image = images[0];
-
-	getVideoDriver()->setRenderTarget(image, true, true,
-			irr::video::SColor(255, skycolor.getRed(), skycolor.getGreen(),
-					skycolor.getBlue()));
-
-	irr::core::vector3df eye_pos;
-	irr::core::matrix4 movement;
-	movement.setTranslation(irr::core::vector3df(
-			(int)psign * g_settings->getFloat("3d_paralax_strength"), 0.0f,
-			0.0f));
-	eye_pos = (startMatrix * movement).getTranslation();
-
-	// clear the depth buffer
-	getVideoDriver()->clearZBuffer();
-	camera->getCameraNode()->setPosition(eye_pos);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&movement);
-	}
-
-	guienv->drawAll();
-
-	/* switch back to real renderer */
-	getVideoDriver()->setRenderTarget(0, true, true,
-			irr::video::SColor(0, skycolor.getRed(), skycolor.getGreen(),
-					skycolor.getBlue()));
-
-	return image;
+	core.reset();
 }
 
-video::ITexture *RenderingEngine::draw_hud(const v2u32 &screensize, bool show_hud,
-		Hud *hud, Client *client, bool draw_crosshair,
-		const video::SColor &skycolor, gui::IGUIEnvironment *guienv,
-		Camera *camera)
+void RenderingEngine::_draw_scene(video::SColor skycolor, bool show_hud,
+		bool show_minimap, bool draw_wield_tool, bool draw_crosshair)
 {
-	static video::ITexture *image = nullptr;
-	init_texture(screensize, &image, "mt_drawimage_hud");
-	getVideoDriver()->setRenderTarget(
-			image, true, true, irr::video::SColor(255, 0, 0, 0));
-
-	if (show_hud) {
-		if (draw_crosshair)
-			hud->drawCrosshair();
-		hud->drawHotbar(client->getPlayerItem());
-		hud->drawLuaElements(camera->getOffset());
-		camera->drawNametags();
-		guienv->drawAll();
-	}
-
-	getVideoDriver()->setRenderTarget(0, true, true,
-			irr::video::SColor(0, skycolor.getRed(), skycolor.getGreen(),
-					skycolor.getBlue()));
-
-	return image;
-}
-
-void RenderingEngine::draw_interlaced_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-		const v2u32 &screensize, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-	/* save current info */
-	irr::core::vector3df oldPosition = camera->getCameraNode()->getPosition();
-	irr::core::vector3df oldTarget = camera->getCameraNode()->getTarget();
-	irr::core::matrix4 startMatrix =
-			camera->getCameraNode()->getAbsoluteTransformation();
-	irr::core::vector3df focusPoint =
-			(camera->getCameraNode()->getTarget() -
-					camera->getCameraNode()->getAbsolutePosition())
-					.setLength(1) +
-			camera->getCameraNode()->getAbsolutePosition();
-
-	/* create left view */
-	video::ITexture *left_image = draw_image(screensize, LEFT, startMatrix,
-			focusPoint, show_hud, camera, hud, draw_wield_tool, client,
-			guienv, skycolor);
-
-	// Right eye...
-	irr::core::vector3df rightEye;
-	irr::core::matrix4 rightMove;
-	rightMove.setTranslation(irr::core::vector3df(
-			g_settings->getFloat("3d_paralax_strength"), 0.0f, 0.0f));
-	rightEye = (startMatrix * rightMove).getTranslation();
-
-	// clear the depth buffer
-	getVideoDriver()->clearZBuffer();
-	camera->getCameraNode()->setPosition(rightEye);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&rightMove);
-	}
-	guienv->drawAll();
-
-	for (unsigned int i = 0; i < screensize.Y; i += 2) {
-#if (IRRLICHT_VERSION_MAJOR >= 1) && (IRRLICHT_VERSION_MINOR >= 8)
-		getVideoDriver()->draw2DImage(left_image,
-				irr::core::position2d<s32>(0, i),
-#else
-		getVideoDriver()->draw2DImage(left_image,
-				irr::core::position2d<s32>(0, screensize.Y - i),
-#endif
-				irr::core::rect<s32>(0, i, screensize.X, i + 1), 0,
-				irr::video::SColor(255, 255, 255, 255), false);
-	}
-
-	/* cleanup */
-	camera->getCameraNode()->setPosition(oldPosition);
-	camera->getCameraNode()->setTarget(oldTarget);
-}
-
-void RenderingEngine::draw_sidebyside_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-		const v2u32 &screensize, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-	/* save current info */
-	irr::core::vector3df oldPosition = camera->getCameraNode()->getPosition();
-	irr::core::vector3df oldTarget = camera->getCameraNode()->getTarget();
-	irr::core::matrix4 startMatrix =
-			camera->getCameraNode()->getAbsoluteTransformation();
-	irr::core::vector3df focusPoint =
-			(camera->getCameraNode()->getTarget() -
-					camera->getCameraNode()->getAbsolutePosition())
-					.setLength(1) +
-			camera->getCameraNode()->getAbsolutePosition();
-
-	/* create left view */
-	video::ITexture *left_image = draw_image(screensize, LEFT, startMatrix,
-			focusPoint, show_hud, camera, hud, draw_wield_tool, client,
-			guienv, skycolor);
-
-	/* create right view */
-	video::ITexture *right_image = draw_image(screensize, RIGHT, startMatrix,
-			focusPoint, show_hud, camera, hud, draw_wield_tool, client,
-			guienv, skycolor);
-
-	/* create hud overlay */
-	video::ITexture *hudtexture = draw_hud(screensize, show_hud, hud, client, false,
-			skycolor, guienv, camera);
-	getVideoDriver()->makeColorKeyTexture(
-			hudtexture, irr::video::SColor(255, 0, 0, 0));
-	// makeColorKeyTexture mirrors texture so we do it twice to get it right again
-	getVideoDriver()->makeColorKeyTexture(
-			hudtexture, irr::video::SColor(255, 0, 0, 0));
-
-	draw2DImageFilterScaled(getVideoDriver(), left_image,
-			irr::core::rect<s32>(0, 0, screensize.X / 2, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			false);
-
-	draw2DImageFilterScaled(getVideoDriver(), hudtexture,
-			irr::core::rect<s32>(0, 0, screensize.X / 2, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			true);
-
-	draw2DImageFilterScaled(getVideoDriver(), right_image,
-			irr::core::rect<s32>(
-					screensize.X / 2, 0, screensize.X, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			false);
-
-	draw2DImageFilterScaled(getVideoDriver(), hudtexture,
-			irr::core::rect<s32>(
-					screensize.X / 2, 0, screensize.X, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			true);
-
-	left_image = nullptr;
-	right_image = nullptr;
-
-	/* cleanup */
-	camera->getCameraNode()->setPosition(oldPosition);
-	camera->getCameraNode()->setTarget(oldTarget);
-}
-
-void RenderingEngine::draw_top_bottom_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-		const v2u32 &screensize, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-	/* save current info */
-	irr::core::vector3df oldPosition = camera->getCameraNode()->getPosition();
-	irr::core::vector3df oldTarget = camera->getCameraNode()->getTarget();
-	irr::core::matrix4 startMatrix =
-			camera->getCameraNode()->getAbsoluteTransformation();
-	irr::core::vector3df focusPoint =
-			(camera->getCameraNode()->getTarget() -
-					camera->getCameraNode()->getAbsolutePosition())
-					.setLength(1) +
-			camera->getCameraNode()->getAbsolutePosition();
-
-	/* create left view */
-	video::ITexture *left_image = draw_image(screensize, LEFT, startMatrix,
-			focusPoint, show_hud, camera, hud, draw_wield_tool, client,
-			guienv, skycolor);
-
-	/* create right view */
-	video::ITexture *right_image = draw_image(screensize, RIGHT, startMatrix,
-			focusPoint, show_hud, camera, hud, draw_wield_tool, client,
-			guienv, skycolor);
-
-	/* create hud overlay */
-	video::ITexture *hudtexture = draw_hud(screensize, show_hud, hud, client, false,
-			skycolor, guienv, camera);
-	getVideoDriver()->makeColorKeyTexture(
-			hudtexture, irr::video::SColor(255, 0, 0, 0));
-	// makeColorKeyTexture mirrors texture so we do it twice to get it right again
-	getVideoDriver()->makeColorKeyTexture(
-			hudtexture, irr::video::SColor(255, 0, 0, 0));
-
-	draw2DImageFilterScaled(getVideoDriver(), left_image,
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y / 2),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			false);
-
-	draw2DImageFilterScaled(getVideoDriver(), hudtexture,
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y / 2),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			true);
-
-	draw2DImageFilterScaled(getVideoDriver(), right_image,
-			irr::core::rect<s32>(
-					0, screensize.Y / 2, screensize.X, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			false);
-
-	draw2DImageFilterScaled(getVideoDriver(), hudtexture,
-			irr::core::rect<s32>(
-					0, screensize.Y / 2, screensize.X, screensize.Y),
-			irr::core::rect<s32>(0, 0, screensize.X, screensize.Y), 0, 0,
-			true);
-
-	left_image = NULL;
-	right_image = NULL;
-
-	/* cleanup */
-	camera->getCameraNode()->setPosition(oldPosition);
-	camera->getCameraNode()->setTarget(oldTarget);
-}
-
-void RenderingEngine::draw_pageflip_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-		const v2u32 &screensize, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-#if IRRLICHT_VERSION_MAJOR == 1 && IRRLICHT_VERSION_MINOR > 8
-	errorstream << "Pageflip 3D mode is not supported"
-		    << " with your Irrlicht version!" << std::endl;
-#else
-	/* preserve old setup*/
-	irr::core::vector3df oldPosition = camera->getCameraNode()->getPosition();
-	irr::core::vector3df oldTarget = camera->getCameraNode()->getTarget();
-
-	irr::core::matrix4 startMatrix =
-			camera->getCameraNode()->getAbsoluteTransformation();
-	irr::core::vector3df focusPoint =
-			(camera->getCameraNode()->getTarget() -
-					camera->getCameraNode()->getAbsolutePosition())
-					.setLength(1) +
-			camera->getCameraNode()->getAbsolutePosition();
-
-	// Left eye...
-	getVideoDriver()->setRenderTarget(irr::video::ERT_STEREO_LEFT_BUFFER);
-
-	irr::core::vector3df leftEye;
-	irr::core::matrix4 leftMove;
-	leftMove.setTranslation(irr::core::vector3df(
-			-g_settings->getFloat("3d_paralax_strength"), 0.0f, 0.0f));
-	leftEye = (startMatrix * leftMove).getTranslation();
-
-	// clear the depth buffer, and color
-	getVideoDriver()->beginScene(true, true, irr::video::SColor(200, 200, 200, 255));
-	camera->getCameraNode()->setPosition(leftEye);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&leftMove);
-		hud->drawHotbar(client->getPlayerItem());
-		hud->drawLuaElements(camera->getOffset());
-		camera->drawNametags();
-	}
-
-	guienv->drawAll();
-
-	// Right eye...
-	getVideoDriver()->setRenderTarget(irr::video::ERT_STEREO_RIGHT_BUFFER);
-
-	irr::core::vector3df rightEye;
-	irr::core::matrix4 rightMove;
-	rightMove.setTranslation(irr::core::vector3df(
-			g_settings->getFloat("3d_paralax_strength"), 0.0f, 0.0f));
-	rightEye = (startMatrix * rightMove).getTranslation();
-
-	// clear the depth buffer, and color
-	getVideoDriver()->beginScene(true, true, irr::video::SColor(200, 200, 200, 255));
-	camera->getCameraNode()->setPosition(rightEye);
-	camera->getCameraNode()->setTarget(focusPoint);
-	get_scene_manager()->drawAll();
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool)
-			camera->drawWieldedTool(&rightMove);
-		hud->drawHotbar(client->getPlayerItem());
-		hud->drawLuaElements(camera->getOffset());
-		camera->drawNametags();
-	}
-
-	guienv->drawAll();
-
-	camera->getCameraNode()->setPosition(oldPosition);
-	camera->getCameraNode()->setTarget(oldTarget);
-#endif
-}
-
-// returns (size / coef), rounded upwards
-inline int scaledown(int coef, int size)
-{
-	return (size + coef - 1) / coef;
-}
-
-void RenderingEngine::draw_plain(Camera *camera, bool show_hud, Hud *hud,
-		const v2u32 &screensize, bool draw_wield_tool, Client *client,
-		gui::IGUIEnvironment *guienv, const video::SColor &skycolor)
-{
-	// Undersampling-specific stuff
-	static video::ITexture *image = NULL;
-	static v2u32 last_pixelated_size = v2u32(0, 0);
-	static thread_local int undersampling = g_settings->getU16("undersampling");
-	v2u32 pixelated_size;
-	v2u32 dest_size;
-	if (undersampling > 0) {
-		pixelated_size = v2u32(scaledown(undersampling, screensize.X),
-				scaledown(undersampling, screensize.Y));
-		dest_size = v2u32(undersampling * pixelated_size.X,
-				undersampling * pixelated_size.Y);
-		if (pixelated_size != last_pixelated_size) {
-			init_texture(pixelated_size, &image, "mt_drawimage_img1");
-			last_pixelated_size = pixelated_size;
-		}
-		getVideoDriver()->setRenderTarget(image, true, true, skycolor);
-	}
-
-	// Render
-	get_scene_manager()->drawAll();
-	getVideoDriver()->setTransform(video::ETS_WORLD, core::IdentityMatrix);
-	if (show_hud) {
-		hud->drawSelectionMesh();
-		if (draw_wield_tool) {
-			camera->drawWieldedTool();
-		}
-	}
-
-	// Upscale lowres render
-	if (undersampling > 0) {
-		getVideoDriver()->setRenderTarget(0, true, true);
-		getVideoDriver()->draw2DImage(image,
-				irr::core::rect<s32>(0, 0, dest_size.X, dest_size.Y),
-				irr::core::rect<s32>(0, 0, pixelated_size.X,
-						pixelated_size.Y));
-	}
+	core->draw(skycolor, show_hud, show_minimap, draw_wield_tool, draw_crosshair);
 }
 
 const char *RenderingEngine::getVideoDriverName(irr::video::E_DRIVER_TYPE type)
diff --git a/src/client/renderingengine.h b/src/client/renderingengine.h
index 40fbaa87d..ac6b6926c 100644
--- a/src/client/renderingengine.h
+++ b/src/client/renderingengine.h
@@ -21,6 +21,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #pragma once
 
 #include <vector>
+#include <memory>
 #include <string>
 #include "irrlichttypes_extrabloated.h"
 #include "debug.h"
@@ -32,6 +33,8 @@ class LocalPlayer;
 class Hud;
 class Minimap;
 
+class RenderingCore;
+
 class RenderingEngine
 {
 public:
@@ -41,7 +44,7 @@ public:
 	v2u32 getWindowSize() const;
 	void setResizable(bool resize);
 
-	video::IVideoDriver *getVideoDriver();
+	video::IVideoDriver *getVideoDriver() { return driver; }
 
 	static const char *getVideoDriverName(irr::video::E_DRIVER_TYPE type);
 	static const char *getVideoDriverFriendlyName(irr::video::E_DRIVER_TYPE type);
@@ -107,15 +110,20 @@ public:
 				text, guienv, tsrc, dtime, percent, clouds);
 	}
 
-	inline static void draw_scene(Camera *camera, Client *client, LocalPlayer *player,
-			Hud *hud, Minimap *mapper, gui::IGUIEnvironment *guienv,
-			const v2u32 &screensize, const video::SColor &skycolor,
-			bool show_hud, bool show_minimap)
+	inline static void draw_scene(video::SColor skycolor, bool show_hud,
+			bool show_minimap, bool draw_wield_tool, bool draw_crosshair)
+	{
+		s_singleton->_draw_scene(skycolor, show_hud, show_minimap,
+				draw_wield_tool, draw_crosshair);
+	}
+
+	inline static void initialize(Client *client, Hud *hud)
 	{
-		s_singleton->_draw_scene(camera, client, player, hud, mapper, guienv,
-				screensize, skycolor, show_hud, show_minimap);
+		s_singleton->_initialize(client, hud);
 	}
 
+	inline static void finalize() { s_singleton->_finalize(); }
+
 	static bool run()
 	{
 		sanity_check(s_singleton && s_singleton->m_device);
@@ -126,60 +134,19 @@ public:
 	static std::vector<irr::video::E_DRIVER_TYPE> getSupportedVideoDrivers();
 
 private:
-	enum parallax_sign
-	{
-		LEFT = -1,
-		RIGHT = 1,
-		EYECOUNT = 2
-	};
-
 	void _draw_load_screen(const std::wstring &text, gui::IGUIEnvironment *guienv,
 			ITextureSource *tsrc, float dtime = 0, int percent = 0,
 			bool clouds = true);
 
-	void _draw_scene(Camera *camera, Client *client, LocalPlayer *player, Hud *hud,
-			Minimap *mapper, gui::IGUIEnvironment *guienv,
-			const v2u32 &screensize, const video::SColor &skycolor,
-			bool show_hud, bool show_minimap);
-
-	void draw_anaglyph_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-			bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv);
-
-	void draw_interlaced_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-			const v2u32 &screensize, bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
-
-	void draw_sidebyside_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-			const v2u32 &screensize, bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
-
-	void draw_top_bottom_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-			const v2u32 &screensize, bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
-
-	void draw_pageflip_3d_mode(Camera *camera, bool show_hud, Hud *hud,
-			const v2u32 &screensize, bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
-
-	void draw_plain(Camera *camera, bool show_hud, Hud *hud, const v2u32 &screensize,
-			bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
-
-	void init_texture(const v2u32 &screensize, video::ITexture **texture,
-			const char *name);
+	void _draw_scene(video::SColor skycolor, bool show_hud, bool show_minimap,
+			bool draw_wield_tool, bool draw_crosshair);
 
-	video::ITexture *draw_image(const v2u32 &screensize, parallax_sign psign,
-			const irr::core::matrix4 &startMatrix,
-			const irr::core::vector3df &focusPoint, bool show_hud,
-			Camera *camera, Hud *hud, bool draw_wield_tool, Client *client,
-			gui::IGUIEnvironment *guienv, const video::SColor &skycolor);
+	void _initialize(Client *client, Hud *hud);
 
-	video::ITexture *draw_hud(const v2u32 &screensize, bool show_hud, Hud *hud,
-			Client *client, bool draw_crosshair,
-			const video::SColor &skycolor, gui::IGUIEnvironment *guienv,
-			Camera *camera);
+	void _finalize();
 
+	std::unique_ptr<RenderingCore> core;
 	irr::IrrlichtDevice *m_device = nullptr;
+	irr::video::IVideoDriver *driver;
 	static RenderingEngine *s_singleton;
 };