From 2b42ea0a429c722bd7c5c67d3815c2ddc8399e78 Mon Sep 17 00:00:00 2001 From: MW Date: Wed, 25 Jul 2007 18:19:38 +0000 Subject: Start of the OpenSim library , for now only contains a few textures. --- .../Channel/Manipulators/AerobicErosion.cs | 424 ++++++++++----------- 1 file changed, 212 insertions(+), 212 deletions(-) (limited to 'OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Manipulators/AerobicErosion.cs') diff --git a/OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Manipulators/AerobicErosion.cs b/OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Manipulators/AerobicErosion.cs index 589d360..5d2b4d4 100644 --- a/OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Manipulators/AerobicErosion.cs +++ b/OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Manipulators/AerobicErosion.cs @@ -1,213 +1,213 @@ -/* -* Copyright (c) Contributors, http://www.openmetaverse.org/ -* See CONTRIBUTORS.TXT for a full list of copyright holders. -* -* Redistribution and use in source and binary forms, with or without -* modification, are permitted provided that the following conditions are met: -* * Redistributions of source code must retain the above copyright -* notice, this list of conditions and the following disclaimer. -* * Redistributions in binary form must reproduce the above copyright -* notice, this list of conditions and the following disclaimer in the -* documentation and/or other materials provided with the distribution. -* * Neither the name of the OpenSim Project nor the -* names of its contributors may be used to endorse or promote products -* derived from this software without specific prior written permission. -* -* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS AND ANY -* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED -* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE -* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY -* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES -* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; -* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND -* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS -* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -* -*/ - -using System; -using System.Collections.Generic; -using System.Text; - -namespace libTerrain -{ - partial class Channel - { - // Ideas for Aerobic erosion - // - // Unlike thermal (gravity) and hydraulic (water suspension) - // aerobic erosion should displace mass by moving sediment - // in "hops". The length of the hop being dictated by the - // presence of sharp cliffs and wind speed. - - // The ability to pickup sediment is defined by the total - // surface area, such that: - // 0 0 0 - // 0 1 0 - // 0 0 0 - // Would be the best possible value for sediment to be - // picked up (total difference = 8) and flatter land - // will erode less quickly. - - // Suspended particles assist the erosion process by hitting - // the surface and chiselling additional particles off faster - // than alone. - - // Particles are deposited when one of two conditions is met - // First: - // When particles hit a wall - such that the - // wind direction points at a difference >= the - // deposition mininum talus. - // Second: - // When wind speed is lowered to below the minimum - // required for transit. An idea for this is to - // use the navier-stokes algorithms for simulating - // pressure across the terrain. - - /// - /// An experimental erosion algorithm developed by Adam. Moves sediment by factoring the surface area of each height point. - /// - /// 0..1 The speed of the wind - /// The minimum angle at which rock is eroded 0..1 (recommended: <= 0.30) - /// The minimum angle at which rock is dropped 0..1 (recommended: >= 0.00) - /// The percentage of rock which can be picked up to pickup 0..1 - /// The number of erosion rounds (recommended: 25+) - /// Drop sediment at the lowest point? - public void AerobicErosion(double windspeed, double pickupTalusMinimum, double dropTalusMinimum, double carry, int rounds, bool lowest, bool usingFluidDynamics) - { - bool debugImages = false; - - Channel wind = new Channel(w, h) ; - Channel sediment = new Channel(w, h); - int x, y, i, j; - - this.Normalise(); - - wind = this.Copy(); - wind.Noise(); - - if (debugImages) - wind.SaveImage("testimg/wind_start.png"); - - if (usingFluidDynamics) - { - wind.navierStokes(20, 0.1, 0.0, 0.0); - } - else - { - wind.Pertubation(30); - } - - if (debugImages) - wind.SaveImage("testimg/wind_begin.png"); - - for (i = 0; i < rounds; i++) - { - // Convert some rocks to sand - for (x = 1; x < w - 1; x++) - { - for (y = 1; y < h - 1; y++) - { - double me = Get(x, y); - double surfacearea = 0.3; // Everything will erode even if it's flat. Just slower. - - for (j = 0; j < 9; j++) - { - int[] coords = Neighbours(NeighbourSystem.Moore, j); - double target = Get(x + coords[0], y + coords[1]); - - surfacearea += Math.Abs(target - me); - } - - double amount = surfacearea * wind.map[x, y] * carry; - - if (amount < 0) - amount = 0; - - if (surfacearea > pickupTalusMinimum) - { - Set(x, y, map[x, y] - amount); - sediment.map[x, y] += amount; - } - } - } - - if (usingFluidDynamics) - { - sediment.navierStokes(7, 0.1, 0.0, 0.1); - - Channel noiseChan = new Channel(w, h); - noiseChan.Noise(); - wind.Blend(noiseChan, 0.01); - - wind.navierStokes(10, 0.1, 0.01, 0.01); - - sediment.Distort(wind, windspeed); - } - else - { - wind.Pertubation(15); // Can do better later - wind.seed++; - sediment.Pertubation(10); // Sediment is blown around a bit - sediment.seed++; - } - - if (debugImages) - wind.SaveImage("testimg/wind_" + i.ToString() + ".png"); - - // Convert some sand to rock - for (x = 1; x < w - 1; x++) - { - for (y = 1; y < h - 1; y++) - { - double me = Get(x, y); - double surfacearea = 0.01; // Flat land does not get deposition - double min = double.MaxValue; - int[] minside = new int[2]; - - for (j = 0; j < 9; j++) - { - int[] coords = Neighbours(NeighbourSystem.Moore, j); - double target = Get(x + coords[0], y + coords[1]); - - surfacearea += Math.Abs(target - me); - - if (target < min && lowest) - { - minside = (int[])coords.Clone(); - min = target; - } - } - - double amount = surfacearea * (1.0 - wind.map[x, y]) * carry; - - if (amount < 0) - amount = 0; - - if (surfacearea > dropTalusMinimum) - { - Set(x + minside[0], y + minside[1], map[x + minside[0], y + minside[1]] + amount); - sediment.map[x, y] -= amount; - } - } - } - - if (debugImages) - sediment.SaveImage("testimg/sediment_" + i.ToString() + ".png"); - - wind.Normalise(); - wind *= windspeed; - - this.Normalise(); - } - - Channel myself = this; - myself += sediment; - myself.Normalise(); - - if (debugImages) - this.SaveImage("testimg/output.png"); - } - } +/* +* Copyright (c) Contributors, http://www.openmetaverse.org/ +* See CONTRIBUTORS.TXT for a full list of copyright holders. +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions are met: +* * Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* * Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in the +* documentation and/or other materials provided with the distribution. +* * Neither the name of the OpenSim Project nor the +* names of its contributors may be used to endorse or promote products +* derived from this software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS AND ANY +* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY +* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +* +*/ + +using System; +using System.Collections.Generic; +using System.Text; + +namespace libTerrain +{ + partial class Channel + { + // Ideas for Aerobic erosion + // + // Unlike thermal (gravity) and hydraulic (water suspension) + // aerobic erosion should displace mass by moving sediment + // in "hops". The length of the hop being dictated by the + // presence of sharp cliffs and wind speed. + + // The ability to pickup sediment is defined by the total + // surface area, such that: + // 0 0 0 + // 0 1 0 + // 0 0 0 + // Would be the best possible value for sediment to be + // picked up (total difference = 8) and flatter land + // will erode less quickly. + + // Suspended particles assist the erosion process by hitting + // the surface and chiselling additional particles off faster + // than alone. + + // Particles are deposited when one of two conditions is met + // First: + // When particles hit a wall - such that the + // wind direction points at a difference >= the + // deposition mininum talus. + // Second: + // When wind speed is lowered to below the minimum + // required for transit. An idea for this is to + // use the navier-stokes algorithms for simulating + // pressure across the terrain. + + /// + /// An experimental erosion algorithm developed by Adam. Moves sediment by factoring the surface area of each height point. + /// + /// 0..1 The speed of the wind + /// The minimum angle at which rock is eroded 0..1 (recommended: <= 0.30) + /// The minimum angle at which rock is dropped 0..1 (recommended: >= 0.00) + /// The percentage of rock which can be picked up to pickup 0..1 + /// The number of erosion rounds (recommended: 25+) + /// Drop sediment at the lowest point? + public void AerobicErosion(double windspeed, double pickupTalusMinimum, double dropTalusMinimum, double carry, int rounds, bool lowest, bool usingFluidDynamics) + { + bool debugImages = false; + + Channel wind = new Channel(w, h) ; + Channel sediment = new Channel(w, h); + int x, y, i, j; + + this.Normalise(); + + wind = this.Copy(); + wind.Noise(); + + if (debugImages) + wind.SaveImage("testimg/wind_start.png"); + + if (usingFluidDynamics) + { + wind.navierStokes(20, 0.1, 0.0, 0.0); + } + else + { + wind.Pertubation(30); + } + + if (debugImages) + wind.SaveImage("testimg/wind_begin.png"); + + for (i = 0; i < rounds; i++) + { + // Convert some rocks to sand + for (x = 1; x < w - 1; x++) + { + for (y = 1; y < h - 1; y++) + { + double me = Get(x, y); + double surfacearea = 0.3; // Everything will erode even if it's flat. Just slower. + + for (j = 0; j < 9; j++) + { + int[] coords = Neighbours(NeighbourSystem.Moore, j); + double target = Get(x + coords[0], y + coords[1]); + + surfacearea += Math.Abs(target - me); + } + + double amount = surfacearea * wind.map[x, y] * carry; + + if (amount < 0) + amount = 0; + + if (surfacearea > pickupTalusMinimum) + { + Set(x, y, map[x, y] - amount); + sediment.map[x, y] += amount; + } + } + } + + if (usingFluidDynamics) + { + sediment.navierStokes(7, 0.1, 0.0, 0.1); + + Channel noiseChan = new Channel(w, h); + noiseChan.Noise(); + wind.Blend(noiseChan, 0.01); + + wind.navierStokes(10, 0.1, 0.01, 0.01); + + sediment.Distort(wind, windspeed); + } + else + { + wind.Pertubation(15); // Can do better later + wind.seed++; + sediment.Pertubation(10); // Sediment is blown around a bit + sediment.seed++; + } + + if (debugImages) + wind.SaveImage("testimg/wind_" + i.ToString() + ".png"); + + // Convert some sand to rock + for (x = 1; x < w - 1; x++) + { + for (y = 1; y < h - 1; y++) + { + double me = Get(x, y); + double surfacearea = 0.01; // Flat land does not get deposition + double min = double.MaxValue; + int[] minside = new int[2]; + + for (j = 0; j < 9; j++) + { + int[] coords = Neighbours(NeighbourSystem.Moore, j); + double target = Get(x + coords[0], y + coords[1]); + + surfacearea += Math.Abs(target - me); + + if (target < min && lowest) + { + minside = (int[])coords.Clone(); + min = target; + } + } + + double amount = surfacearea * (1.0 - wind.map[x, y]) * carry; + + if (amount < 0) + amount = 0; + + if (surfacearea > dropTalusMinimum) + { + Set(x + minside[0], y + minside[1], map[x + minside[0], y + minside[1]] + amount); + sediment.map[x, y] -= amount; + } + } + } + + if (debugImages) + sediment.SaveImage("testimg/sediment_" + i.ToString() + ".png"); + + wind.Normalise(); + wind *= windspeed; + + this.Normalise(); + } + + Channel myself = this; + myself += sediment; + myself.Normalise(); + + if (debugImages) + this.SaveImage("testimg/output.png"); + } + } } \ No newline at end of file -- cgit v1.1