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• Good evening everyone!

I was wondering if there is something equivalent of  GL_NV_blend_equation_advanced for AMD?
Basically I'm trying to find more compatible version of it.

Thank you!

• Hello guys,

How do I know? Why does wavefront not show for me?
I already checked I have non errors yet.

And my download (mega.nz) should it is original but I tried no success...
- Add blend source and png file here I have tried tried,.....

PS: Why is our community not active? I wait very longer. Stop to lie me!
Thanks !

• I wasn't sure if this would be the right place for a topic like this so sorry if it isn't.
I'm currently working on a project for Uni using FreeGLUT to make a simple solar system simulation. I've got to the point where I've implemented all the planets and have used a Scene Graph to link them all together. The issue I'm having with now though is basically the planets and moons orbit correctly at their own orbit speeds.
I'm not really experienced with using matrices for stuff like this so It's likely why I can't figure out how exactly to get it working. This is where I'm applying the transformation matrices, as well as pushing and popping them. This is within the Render function that every planet including the sun and moons will have and run.
if (tag != "Sun") { glRotatef(orbitAngle, orbitRotation.X, orbitRotation.Y, orbitRotation.Z); } glPushMatrix(); glTranslatef(position.X, position.Y, position.Z); glRotatef(rotationAngle, rotation.X, rotation.Y, rotation.Z); glScalef(scale.X, scale.Y, scale.Z); glDrawElements(GL_TRIANGLES, mesh->indiceCount, GL_UNSIGNED_SHORT, mesh->indices); if (tag != "Sun") { glPopMatrix(); } The "If(tag != "Sun")" parts are my attempts are getting the planets to orbit correctly though it likely isn't the way I'm meant to be doing it. So I was wondering if someone would be able to help me? As I really don't have an idea on what I would do to get it working. Using the if statement is truthfully the closest I've got to it working but there are still weird effects like the planets orbiting faster then they should depending on the number of planets actually be updated/rendered.

• Hello everyone,
I have problem with texture

• Hello everyone
For @80bserver8 nice job - I have found Google search. How did you port from Javascript WebGL to C# OpenTK.?
I have been searched Google but it shows f***ing Unity 3D. I really want know how do I understand I want start with OpenTK But I want know where is porting of Javascript and C#?

Thanks!

# OpenGL Trying to reverse the Projection Matrix to Y being up.

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I'm trying out some direct3d stuff coming from opengl and I have a question regarding the projection matrix.

I would like the coordinate system to look like so

     y - 720
^
|
|
|
|
|
|
|
|
0, 0 ---------------------------------> x - 1280


Normally in opengl I would do something like this.

// other code....
glMatrixMode(GL_PROJECTION);
m4 Projection = Orthographic(0.0f, 1280.0f, 0.0f, 720.0f, 1.0f, -1.0f);
// other code....

internal m4
Orthographic(f32 Left, f32 Right, f32 Bottom, f32 Top, f32 Near, f32 Far) {
m4 Result = IdentityMatrix();

Result.m0[0] = 2.0f / (Right  - Left);
Result.m1[1] = 2.0f / (Top - Bottom);
Result.m2[2] = -2.0f / (Far - Near);
Result.m3[0] = -(Right + Left) / (Right - Left);
Result.m3[1] = -(Top + Bottom) / (Top - Bottom);
Result.m3[2] = -(Far + Near) / (Far - Near);

return Result;
}



In direct3d I am doing something similar (or so I think)

D3DXMATRIX ProjectionMatrix;
// I know opengl is right handed so I make a right handed ortho right?
D3DXMatrixOrthoOffCenterRH(&ProjectionMatrix, 0.0f, Width, 0.0f, Height, 1.0f, -1.0f);
Direct3DDevice->SetTransform(D3DTS_PROJECTION, &ProjectionMatrix);


Problem is I don't see anything on the screen and cant seem to figure out how I oriented it.

Edited by mojobojo

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Do you use view matrix with your orthogonal projection? It defines handedness much more, projection matrix does as much as invert the depth axis to conform into depth comparison (postive or negative) according to handedness of view matrix.

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Do you use view matrix with your orthogonal projection? It defines handedness much more, projection matrix does as much as invert the depth axis to conform into depth comparison (postive or negative) according to handedness of view matrix.

I set the view and world matrix to an identity matrix.

D3DXMATRIX IdentityMatrix;
D3DXMatrixIdentity(&IdentityMatrix);
Direct3DDevice->SetTransform(D3DTS_WORLD, &IdentityMatrix);
Direct3DDevice->SetTransform(D3DTS_VIEW, &IdentityMatrix);


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You do not orient it nor translate it, but if you will use both versions, LH and RH for projection, you should spot some object at some point, considering it is in scale of the orthogonal projection- width height top down world values.