Re-implementing GET_OFFSET_FROM_ENTITY_GIVEN_WORLD_COORDS manually?

ikt

I have this class where I don't want to use natives, so I'm trying to re-implement this. Brain says no though.

I thought it should be possible with a few Vector3's:

base position in world coords
base rotation
offset position in world coords

I can't figure it out though. Can anybody help?

Edit - Never mind. I took ScriptHookVDotNet's Camera::GetOffsetInWorldCoords and adapted it for my own, and it seems to work:

    Vector3 GetOffsetInWorldCoords(Vector3 baseP, Vector3 rotation, Vector3 direction, Vector3 offset)
    {
        Vector3 forward = direction;
        const double d2R = 0.01745329251994329576923690768489;
        double num1 = System.Math.Cos(rotation.Y * d2R);
        double x = num1 * System.Math.Cos(-rotation.Z * d2R);
        double y = num1 * System.Math.Sin(rotation.Z * d2R);
        double z = System.Math.Sin(-rotation.Y * d2R);
        Vector3 right = new Vector3((float)x, (float)y, (float)z);
        Vector3 up = Vector3.Cross(right, forward);
        return baseP + (right * offset.X) + (forward * offset.Y) + (up * offset.Z);
    }

Blah, cross products. I never quite understood algebra with vectors.

nmodds

@ikt great job. I made my own implementation using dot product instead. I wish I had searched on google with parameter site: gta5-mods.com instead of just gtaforums.com . I thought there was no information about it, it took me some time to make own re-implementation. I was going to post my findings here as well, but yours is more efficient.

ikt

@nm710
Post it anyway, more choice is always better

nmodds

@ikt Yeah you're right about that, more choice is better.

public Vector3 GetOffsetGivenWorldCoords(Vector3 Origin, Vector3 Rotation, Vector3 Position)
{
    Vector3 RightVector = RelativeRightVector(Rotation);
    Vector3 ForwardVector = RotationToDirection(Rotation);
    return new Vector3(-1 * Vector3.Dot(RightVector, (Origin - Position)), -1 * Vector3.Dot(ForwardVector, (Origin - Position)), Position.Z - Origin.Z);
}
public Vector3 RelativeRightVector(Vector3 Rotation)//source is from scripthookdotnet
{
   double num = Math.Cos(Rotation.Y * (Math.PI / 180.0));
   return new Vector3((float)(Math.Cos(-Rotation.Z * (Math.PI / 180.0)) * num), (float)(Math.Sin(Rotation.Z * (Math.PI / 180.0)) * num), (float)Math.Sin(-Rotation.Y * (Math.PI / 180.0)));
}
public Vector3 RotationToDirection(Vector3 Rotation)//I forgot where I got this from, I had it for a long time
{
   float z = Rotation.Z;
   float num = z * 0.0174532924f;
   float x = Rotation.X;
   float num2 = x * 0.0174532924f;
   float num3 = Math.Abs((float)Math.Cos((double)num2));
   return new Vector3
   {
     X = (-(float)Math.Sin(num)) * num3,
     Y = (float)Math.Cos(num) * num3,
     Z = (float)Math.Sin(num2)
   };
}

nmodds

@ikt I didn't realize your function said "GetOffsetInWorldCoords". My function does the other one and gets the offset.