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• ### Similar Content

• 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 Rotatate a triangle, N00by Question

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I'm using OpenGL for 2 weeks now, so this may be a very n00by question. This is my drawing code: glColor4f(col.Red(),col.Green(),col.Blue(),col.Alpha()); glBindTexture(GL_TEXTURE_2D, sprite); glRotatef(0.5f, 0.0f, 0.0f, 0.0f); glBegin(GL_QUADS); glTexCoord2f(0.0, 0.0); glVertex2f(x, y); glTexCoord2f(1.0, 0.0); glVertex2f(x+width, y); glTexCoord2f(1.0, 1.0); glVertex2f(x+width, y+height); glTexCoord2f(0.0, 1.0); glVertex2f(x, y+height); glEnd (); glBindTexture(GL_TEXTURE_2D, 0); The function glRotatef, does rotate something, but I want it to rotate the Quad only, not everything. I have more drawing code after this, and that is rotated as well! I only want this quad (rectangle) in this code to be rotated. Please help me out! Thanx. BTW: I'm just drawing 2d. 3d is not involved.

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Before you call glRotatef, you could call glPushMatrix in order to save the current matrix. Once your current rendering segment is complete, call glPopMatrix to restore the previous matrix, which will be the one before the rotation was applied.

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Also, you're not specifying an axis to rotate about. Whether you only ue 2D or not is irrelevant, because 2D is only a special case of 3D but it is not treated as a special case by OpenGL. You still need to treat everything as 3D. The axis of rotation should, in your case, probably be the Z-axis.
glRotatef(0.5, 0, 0, 1);

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Should i put PushMatrix before my other drawing codes, and put PopMatrix before the code of a quad to be rotated and PushMatrix after it again? Like this:

PushMatrix();

glColor4f(col.Red(),col.Green(),col.Blue(),col.Alpha());
glBindTexture(GL_TEXTURE_2D, sprite);
glRotatef(0.5f, 0.0f, 0.0f, 0.0f);
glTexCoord2f(0.0, 0.0); glVertex2f(x, y);
glTexCoord2f(1.0, 0.0); glVertex2f(x+width, y);
glTexCoord2f(1.0, 1.0); glVertex2f(x+width, y+height);
glTexCoord2f(0.0, 1.0); glVertex2f(x, y+height);
glEnd ();
glBindTexture(GL_TEXTURE_2D, 0);

PopMatrix();

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Thank you all! I tried to put PushMatrix before all my drawing codes and PopMatrix after, and it worked!

Thank you all for the help!