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Pateman

Member Since 14 Feb 2010
Offline Last Active Feb 16 2013 04:24 PM

Posts I've Made

In Topic: GLSL Skinning problem

21 January 2013 - 10:19 AM

when you create a 'Pad the remaining number of weights with zero' are you also setting the bone ID to something valid?

Yes, I set it to zero, then in the shader I verify whether the bone ID is set to 0, like so:

 

 

mat4 getBoneMatrix(int boneIndex) {
   mat4 retMat = mat4(1.0);
   if (boneIDs[boneIndex] != 0) {
      retMat = boneMatrices[boneIDs[boneIndex]];
   }
   return retMat;   
}

float getWeight(int boneIndex) {
   float res = 1.0;
   if (boneIDs[boneIndex] != 0) {
      res = boneWeights[boneIndex];
   }
   return res;
}

In Topic: [OpenGL 3.x] Camera Matrix Problem

22 February 2010 - 09:08 PM

Unfortunately, there's another problem. I noticed the code I posted doesn't take the direction vector into consideration. It's better explained in the video here:

It seems like the transformation matrix doesn't rotate the axes of an object, so it still moves at the same direction, even though it was rotated. Here's how I wanted to fix that bug:

function TBrainObject.GetMatrix: TBrainMatrix;
var
M: TBrainMatrix;
V: TBrainVector;
begin
if UpdateNeeded then
begin
M := Mat4CreateRotationEuler(FRotation);
V := Mat4ApplyToVector(M, Vec3(0.0, 0.0, -1.0));
V := Vec3Normalize(V);

CachedMatrix := Mat4Scale(Mat4Translate(M,
Vec3Negate(Vec3Add(FPosition, V))), FScale);

UpdateNeeded := False;
end;
Result := CachedMatrix;
end;

But it doesn't seem to help too much.

Can you tell me what's wrong with the code? Or at least suggest some changes?

In Topic: [OpenGL 3.x] Camera Matrix Problem

21 February 2010 - 10:35 AM

Finally, after weeks of struggling, the code works! :D

And here is a step-by-step guide:
1. First of all, I disposed of all my matrix code and rewrote it. Here are the functions you will need to compile the code: http://www.nopaste.pl/Source/mhc.txt
2. Use the following shaders: http://www.nopaste.pl/Source/mhd.txt
3. Your rendering code should look like this:

procedure TMainForm.RenderWorld;
var
Model, View, Proj, MVP: TBrainMatrix;
begin
// Clear the frame buffer
glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT);

// Compute the model-view-projection matrix
Proj := Mat4CreatePerspective(60.0, ClientWidth / ClientHeight, 0.1, 1000.0);
Model := Mat4Translate(Mat4CreateRotationEuler(ModelRotation), Vec3Negate(ModelPosition));
View := Mat4Translate(Mat4CreateRotationEuler(CameraRotation), Vec3Negate(CameraPosition));
View := Mat4Inverse(View);

MVP := Mat4Multiply(Model, Mat4Multiply(View, Proj));

// Update the shader
glUniformMatrix4fv(ShaderManager.ActiveProgram.GetUniformLocation('mvpmatrix'),
1, False, @MVP);

// Rendering code here...
end;

Hope this helps. :)

In Topic: [OpenGL 3.x] Camera Matrix Problem

16 February 2010 - 07:32 AM

Quote:

I can't remember off the top of my head if GLSL expects matrix basis vector elements to be contiguous in memory, so if you're not sure yourself you might double check and make sure you're not missing a transpose somewhere.

I tried inverting the camera matrix, transposing it, and both together, and it still doesn't work.

Quote:

Also, as I mentioned previously it looks like you may be constructing your view matrix incorrectly, so you might take another look at that as well.

The code was used before in a different project and it worked. The same thing is with sending the matrices to GLSL - I carefully followed the examples on the official OpenGL's website. Still, the code doesn't work.

Can you please suggest anything else?

In Topic: [OpenGL 3.x] Camera Matrix Problem

15 February 2010 - 08:36 AM

Oh right, I should've posted the math code, too.

Here's the definition of my vector and matrix type:

{ .: TVector :. }
PVector = ^TVector;
TVector = packed record
case Integer of
0:
(X: Single;
Y: Single;
Z: Single; );
1:
(V: array [0 .. 2] of Single);
end;

{ .: TMatrix :. }
PMatrix = ^TMatrix;
TMatrix = packed record
case Integer of
0:
(_11, _12, _13, _14: Single;
_21, _22, _23, _24: Single;
_31, _32, _33, _34: Single;
_41, _42, _43, _44: Single);
1:
(M: array [0 .. 3, 0 .. 3] of Single);
2:
(V: array [0 .. 15] of Single);
end;

As you can see, both records are unions.

The MatrixTransform function code is as follows:

{ .: MatrixTransform :. }
function MatrixTransform(const Position, Rotation, Scale: TVector): TMatrix;
var
CosRx, CosRy, CosRz: Single;
SinRx, SinRy, SinRz: Single;
begin
CosRx := Cos(Rotation.X); // Used 6x
CosRy := Cos(Rotation.Y); // Used 4x
CosRz := Cos(Rotation.Z); // Used 4x
SinRx := Sin(Rotation.X); // Used 5x
SinRy := Sin(Rotation.Y); // Used 5x
SinRz := Sin(Rotation.Z); // Used 5x
Result := MatrixIdentity;

with Result do
begin
_11 := CosRy * CosRz * Scale.X;
_12 := CosRy * SinRz * Scale.X;
_13 := -SinRy * Scale.X;

_21 := (CosRz * SinRx * SinRy * Scale.Y) - (CosRx * SinRz * Scale.Y);
_22 := (CosRx * CosRz * Scale.Y) + (SinRx * SinRy * SinRz * Scale.Y);
_23 := CosRy * SinRx * Scale.Y;

_31 := (CosRx * CosRz * SinRy * Scale.Z) + (SinRx * SinRz * Scale.Z);
_32 := (-CosRz * SinRx * Scale.Z) + (CosRx * SinRy * SinRz * Scale.Z);
_33 := CosRx * CosRy * Scale.Z;

_41 := Position.X;
_42 := Position.Y;
_43 := Position.Z;
end;
end;

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