diff options
Diffstat (limited to '')
| -rw-r--r-- | OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs | 89 |
1 files changed, 71 insertions, 18 deletions
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs index 1feb153..dc34e1c 100644 --- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs +++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs | |||
| @@ -703,24 +703,77 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api | |||
| 703 | 703 | ||
| 704 | public LSL_Rotation llRotBetween(LSL_Vector a, LSL_Vector b) | 704 | public LSL_Rotation llRotBetween(LSL_Vector a, LSL_Vector b) |
| 705 | { | 705 | { |
| 706 | //A and B should both be normalized | 706 | //A and B should both be normalized |
| 707 | m_host.AddScriptLPS(1); | 707 | m_host.AddScriptLPS(1); |
| 708 | double dotProduct = LSL_Vector.Dot(a, b); | 708 | LSL_Rotation rotBetween; |
| 709 | LSL_Vector crossProduct = LSL_Vector.Cross(a, b); | 709 | // Check for zero vectors. If either is zero, return zero rotation. Otherwise, |
| 710 | double magProduct = LSL_Vector.Mag(a) * LSL_Vector.Mag(b); | 710 | // continue calculation. |
| 711 | double angle = Math.Acos(dotProduct / magProduct); | 711 | if (a == new LSL_Vector(0.0f, 0.0f, 0.0f) || b == new LSL_Vector(0.0f, 0.0f, 0.0f)) |
| 712 | LSL_Vector axis = LSL_Vector.Norm(crossProduct); | 712 | { |
| 713 | double s = Math.Sin(angle / 2); | 713 | rotBetween = new LSL_Rotation(0.0f, 0.0f, 0.0f, 1.0f); |
| 714 | 714 | } | |
| 715 | double x = axis.x * s; | 715 | else |
| 716 | double y = axis.y * s; | 716 | { |
| 717 | double z = axis.z * s; | 717 | a = LSL_Vector.Norm(a); |
| 718 | double w = Math.Cos(angle / 2); | 718 | b = LSL_Vector.Norm(b); |
| 719 | 719 | double dotProduct = LSL_Vector.Dot(a, b); | |
| 720 | if (Double.IsNaN(x) || Double.IsNaN(y) || Double.IsNaN(z) || Double.IsNaN(w)) | 720 | // There are two degenerate cases possible. These are for vectors 180 or |
| 721 | return new LSL_Rotation(0.0f, 0.0f, 0.0f, 1.0f); | 721 | // 0 degrees apart. These have to be detected and handled individually. |
| 722 | 722 | // | |
| 723 | return new LSL_Rotation((float)x, (float)y, (float)z, (float)w); | 723 | // Check for vectors 180 degrees apart. |
| 724 | // A dot product of -1 would mean the angle between vectors is 180 degrees. | ||
| 725 | if (dotProduct < -0.9999999f) | ||
| 726 | { | ||
| 727 | // First assume X axis is orthogonal to the vectors. | ||
| 728 | LSL_Vector orthoVector = new LSL_Vector(1.0f, 0.0f, 0.0f); | ||
| 729 | orthoVector = orthoVector - a * (a.x / LSL_Vector.Dot(a, a)); | ||
| 730 | // Check for near zero vector. A very small non-zero number here will create | ||
| 731 | // a rotation in an undesired direction. | ||
| 732 | if (LSL_Vector.Mag(orthoVector) > 0.0001) | ||
| 733 | { | ||
| 734 | rotBetween = new LSL_Rotation(orthoVector.x, orthoVector.y, orthoVector.z, 0.0f); | ||
| 735 | } | ||
| 736 | // If the magnitude of the vector was near zero, then assume the X axis is not | ||
| 737 | // orthogonal and use the Z axis instead. | ||
| 738 | else | ||
| 739 | { | ||
| 740 | // Set 180 z rotation. | ||
| 741 | rotBetween = new LSL_Rotation(0.0f, 0.0f, 1.0f, 0.0f); | ||
| 742 | } | ||
| 743 | } | ||
| 744 | // Check for parallel vectors. | ||
| 745 | // A dot product of 1 would mean the angle between vectors is 0 degrees. | ||
| 746 | else if (dotProduct > 0.9999999f) | ||
| 747 | { | ||
| 748 | // Set zero rotation. | ||
| 749 | rotBetween = new LSL_Rotation(0.0f, 0.0f, 0.0f, 1.0f); | ||
| 750 | } | ||
| 751 | else | ||
| 752 | { | ||
| 753 | // All special checks have been performed so get the axis of rotation. | ||
| 754 | LSL_Vector crossProduct = LSL_Vector.Cross(a, b); | ||
| 755 | // Quarternion s value is the length of the unit vector + dot product. | ||
| 756 | double qs = 1.0 + dotProduct; | ||
| 757 | rotBetween = new LSL_Rotation(crossProduct.x, crossProduct.y, crossProduct.z, qs); | ||
| 758 | // Normalize the rotation. | ||
| 759 | double mag = LSL_Rotation.Mag(rotBetween); | ||
| 760 | // We shouldn't have to worry about a divide by zero here. The qs value will be | ||
| 761 | // non-zero because we already know if we're here, then the dotProduct is not -1 so | ||
| 762 | // qs will not be zero. Also, we've already handled the input vectors being zero so the | ||
| 763 | // crossProduct vector should also not be zero. | ||
| 764 | rotBetween.x = rotBetween.x / mag; | ||
| 765 | rotBetween.y = rotBetween.y / mag; | ||
| 766 | rotBetween.z = rotBetween.z / mag; | ||
| 767 | rotBetween.s = rotBetween.s / mag; | ||
| 768 | // Check for undefined values and set zero rotation if any found. This code might not actually be required | ||
| 769 | // any longer since zero vectors are checked for at the top. | ||
| 770 | if (Double.IsNaN(rotBetween.x) || Double.IsNaN(rotBetween.y) || Double.IsNaN(rotBetween.z) || Double.IsNaN(rotBetween.s)) | ||
| 771 | { | ||
| 772 | rotBetween = new LSL_Rotation(0.0f, 0.0f, 0.0f, 1.0f); | ||
| 773 | } | ||
| 774 | } | ||
| 775 | } | ||
| 776 | return rotBetween; | ||
| 724 | } | 777 | } |
| 725 | 778 | ||
| 726 | public void llWhisper(int channelID, string text) | 779 | public void llWhisper(int channelID, string text) |