[Resolved] old normals question.

Dx7 VB6

VB Code:

'Calculate Normals
                    ' subtract point2 - point1 to find a vector
                    ' no light, trying new method of point3 - point2
                    DataVector2.X = PointX(3) - PointX(2)
                    DataVector2.Y = PointY(3) - PointY(2)
                    DataVector2.Z = PointZ(3) - PointZ(2)
                    
                    'subtract point3 - point1 to find another vector
                    DataVector3.X = PointX(2) - PointX(1)
                    DataVector3.Y = PointY(2) - PointY(1)
                    DataVector3.Z = PointZ(2) - PointZ(1)
                    
                    
                    ' find vector cross product and store in DV1
                    DataVector1.X = (DataVector2.Y * DataVector3.Z) - (DataVector2.Z * DataVector1.Y)
                    DataVector1.Y = (DataVector2.Z * DataVector3.X) - (DataVector2.X * DataVector1.Z)
                    DataVector1.Z = (DataVector2.X * DataVector3.Y) - (DataVector2.Y * DataVector1.X)
                    
                    ' normalize vector for light
                    Dx.VectorNormalize DataVector1

when i run the program, and i check for the normal of the surface i collide with, i get this in my debug:

Impacted Normal----
-1.#IND
-1.#IND
-1.#IND

it doesn't matter what direction the normal is facing.
i need normals here, not because i'm working with light, but
because i'm working with collisions. it'll help me figure out the sliding.

Am i not doing something wrong?

This is how I do it in DX8:

VB Code:

Public Function Generate_Triangle_Normals(p0 As UNLIT_VERTEX, p1 As UNLIT_VERTEX, p2 As UNLIT_VERTEX) As D3DVECTOR4
 
'//0. Variables required
    Dim v01 As D3DVECTOR 'Vector from points 0 to 1
    Dim v02 As D3DVECTOR 'Vector from points 0 to 2
    Dim vNorm As D3DVECTOR 'The final vector
 
'//1. Create the vectors from points 0 to 1 and 0 to 2
    D3DXVec3Subtract v01, Create_Vector(p1.X, p1.Y, p1.Z), Create_Vector(p0.X, p0.Y, p0.Z)
    D3DXVec3Subtract v02, Create_Vector(p2.X, p2.Y, p2.Z), Create_Vector(p0.X, p0.Y, p0.Z)
 
'//2. Get the cross product
    D3DXVec3Cross vNorm, v01, v02
 
'//3. Normalize this vector
    D3DXVec3Normalize vNorm, vNorm
 
'//4. Return the value
    
    Generate_Triangle_Normals.X = vNorm.X
    Generate_Triangle_Normals.Y = vNorm.Y
    Generate_Triangle_Normals.Z = vNorm.Z
    
End Function

Thanks for the help, i translated it to DX7 but i get an error.
it's made progress but i've started coming with an 'Overflow'.

I set it to tell me the normals in the debug as it generates them.
here's what i come across as output:

VB Code:

Dx.VectorNormalize vNorm ', vNorm
    
Debug.Print "----vnorm"
Debug.Print vNorm.X
Debug.Print vNorm.Y
Debug.Print vNorm.Z
 
'//4. Return the value
 
    If vNorm.Z > 0 Then '<----error line

debug output:
----vnorm
0
0
1
----vnorm
0
0
-1
----vnorm <---- error normal
-1.#IND
-1.#IND
-1.#IND


What could be causing this?

What did you declare your variables as?

D3DVECTORs.
but looking at the latest output it may be a mapping error i'm fighting with. look at the P0 and P1 for the last output.


Debug.Print "--------VNormals----------"
Debug.Print vNorm.X
Debug.Print vNorm.Y
Debug.Print vNorm.Z
Debug.Print "p0----"
Debug.Print p0.X
Debug.Print p0.Y
Debug.Print p0.Z
Debug.Print "p1----"
Debug.Print p1.X
Debug.Print p1.Y
Debug.Print p1.Z
Debug.Print "p2----"
Debug.Print p2.X
Debug.Print p2.Y
Debug.Print p2.Z

--------VNorm----------
0
0
-1
p0----
-8
392
-112
p1----
0
392
-112
p2----
0
248
-112
--------VNorm----------
-1.#IND
-1.#IND
-1.#IND
p0----
0
392
-112
p1----
0
392
-112
p2----
0
248
-112

I accidently gave you the old code I had. Didn't have a choice really since I was at work and my latest DX stuff was at home, so the code I have above should do it. Can you upload the project you have?

Too big.
File Too Large. Limit for this filetype is 500.0 KB. Your file is 1.40 MB.

i have to include certain textures, maps, and model files for it to work.

Ever thought of using DirectX8 instead? They made D3D a lot easier to work with in that one, and DX8 is my strong point.

Why not just go all out and use DX9c?

How much easier could it make it?
hell, to be honest, i can't even remember how i got it to work in Dx7 - been that
long sience i looked at it.

You can't use DX9 in VB6. It's only for the .NET languages.

Yeap, that's micro soft for you.

AKA = bill gate's weenie.

He's forcing everyone to use his "oh I'm so proud of my" .NET framework.

Is that a fact?

Yep. Sad but true. It got to the point to where his new Windows Vista was rumored to run and only run .NET apps as well.

Well, so much for using normals to calculate collisions.

i'm stumped.

I was thinking "hum... if i could use the normals to decide wich way the surface is
facing then i'd know what direction to slide the player/camera"

but now i see that apparently normals are allways possitive. that doesn't seem to
wook too good with my theory.

oops, my bad. apparently i'm colliding into more than one surface at a time and it's
taking the first one it finds, that's all i need to fix. there may be hopes for me yet.

So your problems resolved?

Think so. i just have to figure out how to tell which surface is closest.