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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 Selection Buffer problems

This topic is 4303 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

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Hello all... I've been wrestling with this one for... well, way too long (put my project on hold for nearly a year). Anyways, I've been trying to use the OpenGL selection buffer in my application (a model editor for my game engine) and I'm getting some funky results. First, I'll list some sources of information I've been using: 1. RMS "Using the OpenGL Selection Buffer" 2. OpenGL FAQ Ok, now that you have an idea of what I'm trying to do, here's what's going on. I can click directly on an object I'm trying to select (the whole object shares one name). My hits variable comes back as a '1' (meaning there was one hit) (hits = glRenderMode(GL_RENDER)). However, when I browse the selection buffer, it says that there are no objects in the buffer. What gives? I'll go ahead and post some of the code here. The execution would start at "RenderSelectModel" in the code (after a button has been pressed)
void GLViewPort::RenderSelectModel()
{
StartPicking();
GLuint Position(0);
GLuint hitnames [SELECT_BUFSIZE];
qDebug() << "Select buffer size = " << SELECT_BUFSIZE;
GLuint hi(0);
GLuint * bufp = 0;
GLuint numnames;
for(MyModels->SetBeginning(); !MyModels->CheckEnd(); (*MyModels)++, Position++)
{
/*if(!(Position % SELECT_BUFSIZE))
{
if(Position)
{
glFlush();
hits = StopPicking();
for(unsigned int j = 0; j < hits; j++)
{
numnames = *bufp++;
bufp += 2;
while(numnames--)
{
hitnames[hi++] = *bufp++;
}
}
glRenderMode(GL_SELECT);
}
bufp = select_buf;
}*/
const TriangleOctree * TT = MyModels->GetConst().GetTTree();
glPushMatrix();
const Vector3D * Translation = &MyModels->GetConst().GetTranslation();
const Vector3D * Rotation = &MyModels->GetConst().GetRotation();
const Vector3D * Scale = &MyModels->GetConst().GetScale();
glTranslatef((*Translation)(0), (*Translation)(1), (*Translation)(2));
glRotatef((*Rotation)(0), (*Rotation)(1), (*Rotation)(2), (*Rotation)(3));
glScalef((*Scale)(0), (*Scale)(1), (*Scale)(2));
DrawInternalTree(TT);
glPopMatrix();
}
hits = StopPicking();
bufp = select_buf;
for(unsigned int j = 0; j < hits; j++)
{
numnames = *bufp++;
bufp += 2;
while(numnames--)
{
hitnames[hi++] = *bufp++;
}
}
// OK, all objects have been drawn, and hits have been noted in the "hitnames" variable. The size of this array is
// recorded under the variable "hi"
if(SelectedModel)
{
{
delete SelectedModel;
}
}
if(hi)
{
SelectedModel = MyModels->GetDP(hitnames[0]);
}
CheckError();
}

SELECT_BUFSIZE = 16, in case anyone was wondering. There is a grand total of one model in my model list. Here's the "StartPicking()" and "StopPicking()" functions:
void GLViewPort::StartPicking()
{
glSelectBuffer(SELECT_BUFSIZE, select_buf);
glRenderMode(GL_SELECT);
glInitNames();
setupView();
CheckError();
}

int GLViewPort::StopPicking()
{
// restoring the original projection matrix
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
glFlush();

CheckError();
// returning to normal rendering mode
return glRenderMode(GL_RENDER);
}

void GLViewPort::setupView()
{
glMatrixMode(GL_PROJECTION);
glPushMatrix();
GLint Viewport[4];
glGetIntegerv(GL_VIEWPORT, Viewport);
gluPickMatrix((GLdouble)PressX, (GLdouble)(Viewport[3] - PressY), pickRegionSize, pickRegionSize, Viewport);
gluPerspective(45.0F, GLfloat (Viewport[2]) / Viewport[3], 0.1F, 1000.0F);
glMatrixMode(GL_MODELVIEW);
MyCamera.DoCamera();
CheckError();
}

I'm kinda stuck on this one... anyone see anything blatantly wrong? Thanks

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<bump> Wow, that got buried quick. Anyone ever worked with a selection buffer before? Got better ideas? Thanks