Rewrite rendering engine (#6253)

* Clean draw_*() arguments

* Split rendering core

* Add anaglyph 3D

* Interlaced 3D

* Drop obsolete methods

1 files changed, 76 insertions, 0 deletions

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();
+}