From 7a367f96e15aa6167f1c51b19fd38cffa14f5cc7 Mon Sep 17 00:00:00 2001
From: Perttu Ahola <celeron55@gmail.com>
Date: Fri, 29 Apr 2011 15:34:26 +0300
Subject: added clouds

---
 src/clouds.cpp | 157 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 157 insertions(+)
 create mode 100644 src/clouds.cpp

(limited to 'src/clouds.cpp')

diff --git a/src/clouds.cpp b/src/clouds.cpp
new file mode 100644
index 000000000..20a1c12db
--- /dev/null
+++ b/src/clouds.cpp
@@ -0,0 +1,157 @@
+/*
+Minetest-c55
+Copyright (C) 2010 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 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 General Public License for more details.
+
+You should have received a copy of the GNU 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 "clouds.h"
+#include "noise.h"
+#include "constants.h"
+#include "debug.h"
+
+Clouds::Clouds(
+		scene::ISceneNode* parent,
+		scene::ISceneManager* mgr,
+		s32 id,
+		float cloud_y,
+		u32 seed
+):
+	scene::ISceneNode(parent, mgr, id),
+	m_cloud_y(cloud_y),
+	m_seed(seed),
+	m_camera_pos(0,0),
+	m_time(0)
+{
+	dstream<<__FUNCTION_NAME<<std::endl;
+
+	m_material.setFlag(video::EMF_LIGHTING, false);
+	m_material.setFlag(video::EMF_BACK_FACE_CULLING, false);
+	m_material.setFlag(video::EMF_BILINEAR_FILTER, false);
+	m_material.setFlag(video::EMF_FOG_ENABLE, false);
+	//m_material.setFlag(video::EMF_ANTI_ALIASING, true);
+	//m_material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
+
+	m_box = core::aabbox3d<f32>(-BS*1000000,cloud_y-BS,-BS*1000000,
+			BS*1000000,cloud_y+BS,BS*1000000);
+
+}
+
+Clouds::~Clouds()
+{
+	dstream<<__FUNCTION_NAME<<std::endl;
+}
+
+void Clouds::OnRegisterSceneNode()
+{
+	if(IsVisible)
+	{
+		SceneManager->registerNodeForRendering(this, scene::ESNRP_SOLID);
+		//SceneManager->registerNodeForRendering(this, scene::ESNRP_TRANSPARENT);
+	}
+
+	ISceneNode::OnRegisterSceneNode();
+}
+
+#define MYROUND(x) (x > 0.0 ? (int)x : (int)x - 1)
+
+void Clouds::render()
+{
+	video::IVideoDriver* driver = SceneManager->getVideoDriver();
+
+	/*if(SceneManager->getSceneNodeRenderPass() != scene::ESNRP_TRANSPARENT)
+		return;*/
+	if(SceneManager->getSceneNodeRenderPass() != scene::ESNRP_SOLID)
+		return;
+
+	driver->setTransform(video::ETS_WORLD, AbsoluteTransformation);
+	driver->setMaterial(m_material);
+	
+	/*
+		Clouds move from X+ towards X-
+	*/
+
+	const s16 cloud_radius_i = 12;
+	const float cloud_size = BS*50;
+	const v2f cloud_speed(-BS*2, 0);
+	
+	// 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;
+	// 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
+	v2s16 center_of_drawing_in_noise_i(
+		MYROUND(center_of_drawing_in_noise_f.X / cloud_size),
+		MYROUND(center_of_drawing_in_noise_f.Y / cloud_size)
+	);
+	// The world position of the integer center point of drawing in the noise
+	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;
+
+	for(s16 zi=-cloud_radius_i; zi<cloud_radius_i; zi++)
+	for(s16 xi=-cloud_radius_i; xi<cloud_radius_i; xi++)
+	{
+		v2s16 p_in_noise_i(
+			xi+center_of_drawing_in_noise_i.X,
+			zi+center_of_drawing_in_noise_i.Y
+		);
+
+		/*if((p_in_noise_i.X + p_in_noise_i.Y)%2==0)
+			continue;*/
+		/*if((p_in_noise_i.X/2 + p_in_noise_i.Y/2)%2==0)
+			continue;*/
+
+		v2f p0 = v2f(xi,zi)*cloud_size + world_center_of_drawing_in_noise_f;
+		
+		double noise = noise2d_perlin(
+				(float)p_in_noise_i.X*cloud_size/BS/100,
+				(float)p_in_noise_i.Y*cloud_size/BS/100,
+				m_seed, 3, 0.5);
+		if(noise < 0)
+			continue;
+		
+		v2f p1 = p0 + v2f(1,1)*cloud_size;
+
+		//video::SColor c(128,255,255,255);
+		float b = m_brightness;
+		video::SColor c(128,b*230,b*230,b*255);
+		video::S3DVertex vertices[4] =
+		{
+			video::S3DVertex(p0.X,m_cloud_y,p0.Y, 0,0,0, c, 0,1),
+			video::S3DVertex(p0.X,m_cloud_y,p1.Y, 0,0,0, c, 1,1),
+			video::S3DVertex(p1.X,m_cloud_y,p1.Y, 0,0,0, c, 1,0),
+			video::S3DVertex(p1.X,m_cloud_y,p0.Y, 0,0,0, c, 0,0),
+		};
+		u16 indices[] = {0,1,2,2,3,0};
+		driver->drawVertexPrimitiveList(vertices, 4, indices, 2,
+				video::EVT_STANDARD, scene::EPT_TRIANGLES, video::EIT_16BIT);
+	}
+}
+
+void Clouds::step(float dtime)
+{
+	m_time += dtime;
+}
+
+void Clouds::update(v2f camera_p, float brightness)
+{
+	m_camera_pos = camera_p;
+	m_brightness = brightness;
+}
+
-- 
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