Replace CalculateMass with a better, contributed version

1 files changed, 228 insertions, 243 deletions

diff --git a/OpenSim/Region/Physics/ChOdePlugin/ODEPrim.cs b/OpenSim/Region/Physics/ChOdePlugin/ODEPrim.cs
index 2105be1..793774a 100644
--- a/OpenSim/Region/Physics/ChOdePlugin/ODEPrim.cs
+++ b/OpenSim/Region/Physics/ChOdePlugin/ODEPrim.cs
@@ -884,300 +884,285 @@ namespace OpenSim.Region.Physics.OdePlugin
 
         private float CalculateMass()
         {
-            float volume = 0;
-
-            // No material is passed to the physics engines yet..  soo..
-            // we're using the m_density constant in the class definition
+            float volume = _size.X * _size.Y * _size.Z; // default
+            float tmp;
 
             float returnMass = 0;
-
+            float hollowAmount = (float)_pbs.ProfileHollow * 2.0e-5f;
+            float hollowVolume = hollowAmount * hollowAmount; 
+            
             switch (_pbs.ProfileShape)
             {
                 case ProfileShape.Square:
-                    // Profile Volume
+                    // default box
+
+                    if (_pbs.PathCurve == (byte)Extrusion.Straight)
+                        {
+                        if (hollowAmount > 0.0)
+                            {
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Square:
+                                case HollowShape.Same:
+                                    break;
 
-                    volume = _size.X*_size.Y*_size.Z;
+                                case HollowShape.Circle:
 
-                    // If the user has 'hollowed out'
-                    // ProfileHollow is one of those 0 to 50000 values :P
-                    // we like percentages better..   so turning into a percentage
+                                    hollowVolume *= 0.78539816339f;
+                                    break;
 
-                    if (((float) _pbs.ProfileHollow/50000f) > 0.0)
-                    {
-                        float hollowAmount = (float) _pbs.ProfileHollow/50000f;
+                                case HollowShape.Triangle:
+
+                                    hollowVolume *= (0.5f * .5f);
+                                    break;
+
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
+                        }
 
-                        // calculate the hollow volume by it's shape compared to the prim shape
-                        float hollowVolume = 0;
-                        switch (_pbs.HollowShape)
+                    else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
                         {
-                            case HollowShape.Square:
-                            case HollowShape.Same:
-                                // Cube Hollow volume calculation
-                                float hollowsizex = _size.X*hollowAmount;
-                                float hollowsizey = _size.Y*hollowAmount;
-                                float hollowsizez = _size.Z*hollowAmount;
-                                hollowVolume = hollowsizex*hollowsizey*hollowsizez;
-                                break;
-
-                            case HollowShape.Circle:
-                                // Hollow shape is a perfect cyllinder in respect to the cube's scale
-                                // Cyllinder hollow volume calculation
-                                float hRadius = _size.X/2;
-                                float hLength = _size.Z;
-
-                                // pi * r2 * h
-                                hollowVolume = ((float) (Math.PI*Math.Pow(hRadius, 2)*hLength)*hollowAmount);
-                                break;
-
-                            case HollowShape.Triangle:
-                                // Equilateral Triangular Prism volume hollow calculation
-                                // Triangle is an Equilateral Triangular Prism with aLength = to _size.Y
-
-                                float aLength = _size.Y;
-                                // 1/2 abh
-                                hollowVolume = (float) ((0.5*aLength*_size.X*_size.Z)*hollowAmount);
-                                break;
-
-                            default:
-                                hollowVolume = 0;
-                                break;
+                        //a tube 
+
+                        volume *= 0.78539816339e-2f * (float)(200 - _pbs.PathScaleX);
+                        tmp= 1.0f -2.0e-2f * (float)(200 - _pbs.PathScaleY);
+                        volume -= volume*tmp*tmp;
+                        
+                        if (hollowAmount > 0.0)
+                            {
+                            hollowVolume *= hollowAmount;
+                            
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Square:
+                                case HollowShape.Same:
+                                    break;
+
+                                case HollowShape.Circle:
+                                    hollowVolume *= 0.78539816339f;;
+                                    break;
+
+                                case HollowShape.Triangle:
+                                    hollowVolume *= 0.5f * 0.5f;
+                                    break;
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
                         }
-                        volume = volume - hollowVolume;
-                    }
 
                     break;
+
                 case ProfileShape.Circle:
-                    if (_pbs.PathCurve == (byte)Extrusion.Straight)
-                    {
-                        // Cylinder
-                        float volume1 = (float)(Math.PI * Math.Pow(_size.X/2, 2) * _size.Z);
-                        float volume2 = (float)(Math.PI * Math.Pow(_size.Y/2, 2) * _size.Z);
 
-                        // Approximating the cylinder's irregularity.
-                        if (volume1 > volume2)
-                        {
-                            volume = (float)volume1 - (volume1 - volume2);
-                        }
-                        else if (volume2 > volume1)
+                    if (_pbs.PathCurve == (byte)Extrusion.Straight)
                         {
-                            volume = (float)volume2 - (volume2 - volume1);
+                        volume *= 0.78539816339f; // elipse base
+
+                        if (hollowAmount > 0.0)
+                            {
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Same:
+                                case HollowShape.Circle:
+                                    break;
+
+                                case HollowShape.Square:
+                                    hollowVolume *= 0.5f * 2.5984480504799f;
+                                    break;
+
+                                case HollowShape.Triangle:
+                                    hollowVolume *= .5f * 1.27323954473516f;
+                                    break;
+
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
                         }
-                        else
+
+                    else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
                         {
-                            // Regular cylinder
-                            volume = volume1;
-                        }
-                    }
-                    else
-                    {
-                        // We don't know what the shape is yet, so use default
-                        volume = _size.X * _size.Y * _size.Z;
-                    }
-                    // If the user has 'hollowed out'
-                    // ProfileHollow is one of those 0 to 50000 values :P
-                    // we like percentages better..   so turning into a percentage
+                        volume *= 0.61685027506808491367715568749226e-2f * (float)(200 - _pbs.PathScaleX);
+                        tmp = 1.0f - .02f * (float)(200 - _pbs.PathScaleY);
+                        volume *= (1.0f - tmp * tmp);
+                        
+                        if (hollowAmount > 0.0)
+                            {
 
-                    if (((float)_pbs.ProfileHollow / 50000f) > 0.0)
-                    {
-                        float hollowAmount = (float)_pbs.ProfileHollow / 50000f;
+                            // calculate the hollow volume by it's shape compared to the prim shape
+                            hollowVolume *= hollowAmount;
 
-                        // calculate the hollow volume by it's shape compared to the prim shape
-                        float hollowVolume = 0;
-                        switch (_pbs.HollowShape)
-                        {
-                            case HollowShape.Same:
-                            case HollowShape.Circle:
-                                // Hollow shape is a perfect cyllinder in respect to the cube's scale
-                                // Cyllinder hollow volume calculation
-                                float hRadius = _size.X / 2;
-                                float hLength = _size.Z;
-
-                                // pi * r2 * h
-                                hollowVolume = ((float)(Math.PI * Math.Pow(hRadius, 2) * hLength) * hollowAmount);
-                                break;
-
-                            case HollowShape.Square:
-                                // Cube Hollow volume calculation
-                                float hollowsizex = _size.X * hollowAmount;
-                                float hollowsizey = _size.Y * hollowAmount;
-                                float hollowsizez = _size.Z * hollowAmount;
-                                hollowVolume = hollowsizex * hollowsizey * hollowsizez;
-                                break;
-
-                            case HollowShape.Triangle:
-                                // Equilateral Triangular Prism volume hollow calculation
-                                // Triangle is an Equilateral Triangular Prism with aLength = to _size.Y
-
-                                float aLength = _size.Y;
-                                // 1/2 abh
-                                hollowVolume = (float)((0.5 * aLength * _size.X * _size.Z) * hollowAmount);
-                                break;
-
-                            default:
-                                hollowVolume = 0;
-                                break;
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Same:
+                                case HollowShape.Circle:
+                                    break;
+
+                                case HollowShape.Square:
+                                    hollowVolume *= 0.5f * 2.5984480504799f;
+                                    break;
+
+                                case HollowShape.Triangle:
+                                    hollowVolume *= .5f * 1.27323954473516f;
+                                    break;
+
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
                         }
-                        volume = volume - hollowVolume;
-                    }
                     break;
 
                 case ProfileShape.HalfCircle:
                     if (_pbs.PathCurve == (byte)Extrusion.Curve1)
                     {
-                        if (_size.X == _size.Y && _size.Y == _size.Z)
-                        {
-                            // regular sphere
-                            // v = 4/3 * pi * r^3
-                            float sradius3 = (float)Math.Pow((_size.X / 2), 3);
-                            volume = (float)((4f / 3f) * Math.PI * sradius3);
-                        }
-                        else
-                        {
-                            // we treat this as a box currently
-                            volume = _size.X * _size.Y * _size.Z;
-                        }
-                    }
-                    else
-                    {
-                        // We don't know what the shape is yet, so use default
-                        volume = _size.X * _size.Y * _size.Z;
+                    volume *= 0.52359877559829887307710723054658f;
                     }
                     break;
 
                 case ProfileShape.EquilateralTriangle:
-                    /*
-                        v = (abs((xB*yA-xA*yB)+(xC*yB-xB*yC)+(xA*yC-xC*yA))/2) * h
 
-                        // seed mesh
-                        Vertex MM = new Vertex(-0.25f, -0.45f, 0.0f);
-                        Vertex PM = new Vertex(+0.5f, 0f, 0.0f);
-                        Vertex PP = new Vertex(-0.25f, +0.45f, 0.0f);
-                     */
-                    float xA = -0.25f * _size.X;
-                    float yA = -0.45f * _size.Y;
+                    if (_pbs.PathCurve == (byte)Extrusion.Straight)
+                        {
+                        volume *= 0.32475953f;
 
-                    float xB = 0.5f * _size.X;
-                    float yB = 0;
+                        if (hollowAmount > 0.0)
+                            {
 
-                    float xC = -0.25f * _size.X;
-                    float yC = 0.45f * _size.Y;
+                            // calculate the hollow volume by it's shape compared to the prim shape
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Same:
+                                case HollowShape.Triangle:
+                                    hollowVolume *= .25f;
+                                    break;
 
-                    volume = (float)((Math.Abs((xB * yA - xA * yB) + (xC * yB - xB * yC) + (xA * yC - xC * yA)) / 2) * _size.Z);
+                                case HollowShape.Square:
+                                    hollowVolume *= 0.499849f * 3.07920140172638f;
+                                    break;
 
-                    // If the user has 'hollowed out'
-                    // ProfileHollow is one of those 0 to 50000 values :P
-                    // we like percentages better..   so turning into a percentage
-                    float fhollowFactor = ((float)_pbs.ProfileHollow / 1.9f);
-                    if (((float)fhollowFactor / 50000f) > 0.0)
-                    {
-                        float hollowAmount = (float)fhollowFactor / 50000f;
+                                case HollowShape.Circle:
+                                    // Hollow shape is a perfect cyllinder in respect to the cube's scale
+                                    // Cyllinder hollow volume calculation
 
-                        // calculate the hollow volume by it's shape compared to the prim shape
-                        float hollowVolume = 0;
-                        switch (_pbs.HollowShape)
-                        {
-                            case HollowShape.Same:
-                            case HollowShape.Triangle:
-                                // Equilateral Triangular Prism volume hollow calculation
-                                // Triangle is an Equilateral Triangular Prism with aLength = to _size.Y
-
-                                float aLength = _size.Y;
-                                // 1/2 abh
-                                hollowVolume = (float)((0.5 * aLength * _size.X * _size.Z) * hollowAmount);
-                                break;
-
-                            case HollowShape.Square:
-                                // Cube Hollow volume calculation
-                                float hollowsizex = _size.X * hollowAmount;
-                                float hollowsizey = _size.Y * hollowAmount;
-                                float hollowsizez = _size.Z * hollowAmount;
-                                hollowVolume = hollowsizex * hollowsizey * hollowsizez;
-                                break;
-
-                            case HollowShape.Circle:
-                                // Hollow shape is a perfect cyllinder in respect to the cube's scale
-                                // Cyllinder hollow volume calculation
-                                float hRadius = _size.X / 2;
-                                float hLength = _size.Z;
-
-                                // pi * r2 * h
-                                hollowVolume = ((float)((Math.PI * Math.Pow(hRadius, 2) * hLength)/2) * hollowAmount);
-                                break;
-
-                            default:
-                                hollowVolume = 0;
-                                break;
+                                    hollowVolume *= 0.1963495f * 3.07920140172638f;
+                                    break;
+
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
                         }
-                        volume = volume - hollowVolume;
-                    }
-                    break;
+                    else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
+                        {
+                        volume *= 0.32475953f;
+                        volume *= 0.01f * (float)(200 - _pbs.PathScaleX);
+                        tmp = 1.0f - .02f * (float)(200 - _pbs.PathScaleY);
+                        volume *= (1.0f - tmp * tmp);
 
-                default:
-                    // we don't have all of the volume formulas yet so
-                    // use the common volume formula for all
-                    volume = _size.X*_size.Y*_size.Z;
-                    break;
-            }
+                        if (hollowAmount > 0.0)
+                            {
 
-            // Calculate Path cut effect on volume
-            // Not exact, in the triangle hollow example
-            // They should never be zero or less then zero..
-            // we'll ignore it if it's less then zero
+                            hollowVolume *= hollowAmount;
 
-            // ProfileEnd and ProfileBegin are values
-            // from 0 to 50000
+                            switch (_pbs.HollowShape)
+                                {
+                                case HollowShape.Same:
+                                case HollowShape.Triangle:
+                                    hollowVolume *= .25f;
+                                    break;
 
-            // Turning them back into percentages so that I can cut that percentage off the volume
+                                case HollowShape.Square:
+                                    hollowVolume *= 0.499849f * 3.07920140172638f;
+                                    break;
 
-            float PathCutEndAmount = _pbs.ProfileEnd;
-            float PathCutStartAmount = _pbs.ProfileBegin;
-            if (((PathCutStartAmount + PathCutEndAmount)/50000f) > 0.0f)
-            {
-                float pathCutAmount = ((PathCutStartAmount + PathCutEndAmount)/50000f);
+                                case HollowShape.Circle:
 
-                // Check the return amount for sanity
-                if (pathCutAmount >= 0.99f)
-                    pathCutAmount = 0.99f;
+                                    hollowVolume *= 0.1963495f * 3.07920140172638f;
+                                    break;
 
-                volume = volume - (volume*pathCutAmount);
-            }
-            UInt16 taperX = _pbs.PathScaleX;
-            UInt16 taperY = _pbs.PathScaleY;
-            float taperFactorX = 0;
-            float taperFactorY = 0;
+                                default:
+                                    hollowVolume = 0;
+                                    break;
+                                }
+                            volume *= (1.0f - hollowVolume);
+                            }
+                        }
+                        break;                  
 
-            // Mass = density * volume
-            if (taperX != 100)
-            {
-                if (taperX > 100)
-                {
-                    taperFactorX = 1.0f - ((float)taperX / 200);
-                    //m_log.Warn("taperTopFactorX: " + extr.taperTopFactorX.ToString());
-                }
-                else
-                {
-                    taperFactorX = 1.0f - ((100 - (float)taperX) / 100);
-                    //m_log.Warn("taperBotFactorX: " + extr.taperBotFactorX.ToString());
+                default:
+                    break;
                 }
-                volume = (float)volume * ((taperFactorX / 3f) + 0.001f);
-            }
 
-            if (taperY != 100)
-            {
-                if (taperY > 100)
+
+
+            float taperX1;
+            float taperY1;
+            float taperX;
+            float taperY;
+            float pathBegin;
+            float pathEnd;
+            float profileBegin;
+            float profileEnd;
+
+            if (_pbs.PathCurve == (byte)Extrusion.Straight || _pbs.PathCurve == (byte)Extrusion.Flexible)
                 {
-                    taperFactorY = 1.0f - ((float)taperY / 200);
-                    //m_log.Warn("taperTopFactorY: " + extr.taperTopFactorY.ToString());
+                taperX1 = _pbs.PathScaleX * 0.01f;
+                if (taperX1 > 1.0f)
+                    taperX1 = 2.0f - taperX1;
+                taperX = 1.0f - taperX1;
+
+                taperY1 = _pbs.PathScaleY * 0.01f;
+                if (taperY1 > 1.0f)
+                    taperY1 = 2.0f - taperY1;
+                taperY = 1.0f - taperY1;
                 }
-                else
+            else
                 {
-                    taperFactorY = 1.0f - ((100 - (float)taperY) / 100);
-                    //m_log.Warn("taperBotFactorY: " + extr.taperBotFactorY.ToString());
+                taperX = _pbs.PathTaperX * 0.01f;
+                if (taperX < 0.0f)
+                    taperX = -taperX;
+                taperX1 = 1.0f - taperX;
+
+                taperY = _pbs.PathTaperY * 0.01f;
+                if (taperY < 0.0f)
+                    taperY = -taperY;               
+                taperY1 = 1.0f - taperY;
+
                 }
-                volume = (float)volume * ((taperFactorY / 3f) + 0.001f);
-            }
-            returnMass = m_density*volume;
-            if (returnMass <= 0) returnMass = 0.0001f;//ckrinke: Mass must be greater then zero.
+
+
+            volume *= (taperX1 * taperY1 + 0.5f * (taperX1 * taperY + taperX * taperY1) + 0.3333333333f * taperX * taperY);
+
+            pathBegin = (float)_pbs.PathBegin * 2.0e-5f;
+            pathEnd = 1.0f - (float)_pbs.PathEnd * 2.0e-5f;
+            volume *= (pathEnd - pathBegin);
+
+// this is crude aproximation
+            profileBegin = (float)_pbs.ProfileBegin * 2.0e-5f;
+            profileEnd = 1.0f - (float)_pbs.ProfileEnd * 2.0e-5f;
+            volume *= (profileEnd - profileBegin);
+
+            returnMass = m_density * volume;
+
+            if (returnMass <= 0)
+                returnMass = 0.0001f;//ckrinke: Mass must be greater then zero.
+//            else if (returnMass > _parent_scene.maximumMassObject)
+//                returnMass = _parent_scene.maximumMassObject;
+