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• 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!
• By mike44
Hi
I draw in a OpenGL framebuffer. All is fine but it eats FPS (frames per second), hence I wonder if I could execute the framebuffer drawing only every 5-10th loop or so?
Many thanks

# OpenGL Lighting (complete darkness not working)

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I'm having trouble getting rid of all lighting in a scene (ie, I want the screen completely black). There always seems to be a very low ambient light in the scene. I first tried setting the ambient and diffuse settings to black, that didn't work. I then disabled all 8 light sources (0-7) but still have the same problem. Setting material properties to black fixes the problem, but I don't want everything with a black material (there will be point lights eventually). Any ideas? (this is for opengl in case you didn't notice which forum it's in)

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Can you provide some code/screenshots?

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This is some test code to make sure everything is off:
	static GLfloat dummy[4] = {0.0, 0.0, 0.0, 1.0};	for( int i = GL_LIGHT0; i <= GL_LIGHT7; i++ )	{		glLightfv(i, GL_AMBIENT, dummy);		glLightfv(i, GL_DIFFUSE, dummy);		glLightfv(i, GL_POSITION,dummy);		glLightfv(i, GL_SPECULAR,dummy);		glDisable(i);	}

I wouldn't normally iterate through them like this, but I checked the header and they're all in order (this is quick and dirty testing).

I don't know what other source to show you. There's a lot more! If there's anything in particular you'd like to see I'll post it. At this point all light should be completely off, but it's not for some reason.

I'll put some screenshots up after I've tried some things. The only spot I have to put them right now is my google page. All I'm seeing is a very subtle ambient light in the scene, probably close to the opengl default of (0.2, 0.2, 0.2).

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Screenshot here:

I'm going to try the nehe lighting tutorial to simplify the problem.

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I think for setting the light to black you have to set the fourth light value to 0.0 (i.e. {0.0, 0.0, 0.0, 0.0} ).

Edit: err, I think I'm bein' stupid. :P Heh. Umm, I think I'm thinkin' of something with material properties like you mentioned... Hrm...

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This is odd.
'glDisable' should work fine.
Have you tried disabling the lights manually, rather than using a loop?
Strange advice, I know, but try it anyway.

Try replacing '<=' with a '!='.

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This is very weird, but I figured it out (sort of).

You wouldn't normally see this behavior, as the default material value for ambient light is 0.2 across the board. (0.8 diffuse). I was setting them both to 1.0. Note: this is the material, not the light I'm setting.

This could be my graphics card, or a driver problem, but even with all lights turned off, there is still a slight ambient light in the scene. I got this behavior even with Nehe's lesson 6. With a material value of 0.2 ambient, it's hardly noticable (but you CAN still see it). With my material ambient of 1.0, it was more obvious.

I'm going to retweak my lighting values to see if I can get it looking good with 0.2 ambient materials. I'll try it on my system at work on Monday to see if it's a gfx card thing.