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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!

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## Recommended Posts

Hello, I have somehow built a model (partial) which looks like a stadium. I have attached the picture for your kind perusal. The field ground has been textured. Now for a particular position, my model looks too much lighted as you can see the far half of the seats look totally white. I am a bit new in modeling lighting. If I don't consider the specular parameter, my model looks dull and seats are not properly outlined. So I added some specular component of light and shininess to the model. But the far half of the model looks too much lighted. I found textured portion is unaffected by lighting. Could any one explain why?
Could any one suggest how can I adjust the lighting parameters so that model does not look too shiny and seats around the field are also properly outlined.

I am using simple OpenGL, no GLSL.

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Show us the relevant code you're using so we can see your configuration. Edited by GeneralQuery

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void initGL(){

static const GLfloat light_model_ambient[] = {1.0f, 1.0f, 1.0f, 1.0f};

glLightModelfv(GL_LIGHT_MODEL_AMBIENT, light_model_ambient);

glEnable(GL_DEPTH_TEST);

float diffuse[]  = {1.0f, 1.0f, 1.0f, 1.0f};
float position[] = {5.0f, 5.0f, 5.0f, 1.0f};
float specular[] = {1.0f, 1.0f, 1.0f, 1.0f};

glEnable(GL_LIGHTING);
glEnable( GL_LIGHT0);
glLightfv(GL_LIGHT0, GL_DIFFUSE,  diffuse);
glLightfv(GL_LIGHT0, GL_POSITION, position);
glLightfv(GL_LIGHT0, GL_SPECULAR, specular);

glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

float shininess = 5.0f;
glEnable(GL_COLOR_MATERIAL);
glMaterialf( GL_FRONT_AND_BACK, GL_SHININESS, shininess);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR,  specular);

}

void drawSceneGraphics()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

//Render the checked floor.
glEnable(GL_BLEND);
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
renderAll();

glDisable(GL_BLEND);
}


void renderAll(){

glPushMatrix();

//Render the middle textured field

glEnable(GL_TEXTURE_2D);
renderField(size);
glDisable(GL_TEXTURE_2D);
glPopMatrix();

// Render track 1 (red color)

glPushMatrix();
renderTexturedTrack_1(size);
glPopMatrix();

// Render Track 2 (blue color)

glPushMatrix();
renderTexturedTrack_2(size);
glPopMatrix();

// Render seats

glPushMatrix();
drawModel();
glPopMatrix();

return;
}


Thanks in advance to all.
void glutReshape(int width, int height)
{

static const double kPI = 3.1415926535897932384626433832795;
static const double kFovY = 45;

double nearDist, farDist, aspect;

width =  glutGet(GLUT_WINDOW_WIDTH);
height = glutGet(GLUT_WINDOW_HEIGHT);

if (width && height)
{
glViewport(0, 0, width, height);

// Compute the viewing parameters based on a fixed fov and viewing
// a canonical box centered at the origin.

nearDist = 15.0 / tan((kFovY / 2.0) * kPI / 180.0);
farDist = nearDist + 70.0;
aspect = (double) width / height;

glMatrixMode(GL_PROJECTION);
gluPerspective(kFovY, aspect, 0.1, 140);

// Place the camera down the Z axis looking at the origin.

glMatrixMode(GL_MODELVIEW);

gluLookAt(0, 25.0, nearDist + 35.0, 0, 0.0, 0, 0, 1, 0.0);

}
}



I have attached some part of my code. Please provide me some suggestions so that I can fix the lighting parameters.

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Your lighting terms don't look right. From a brief skim of your code:

Why is the ambient term at full intensity? It shouldn't be otherwise you have no dynamic range to work with (hence the washed out lighting). Try a lower value like 0.2f.

Your specular shininess is very broad. A low number such as the one you are using will wash out a lot of your model, especially with vertex lighting (which you are using). Try a higher value like 64.0f or 128.0f.

Your specular term is very bright. This may be contributing to your problem so try a lower value like 0.8f.

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Hi, thank you very much for taking time to answer my question. As per your suggestion I have changed the lighting parameters as follows:

The attached picture is for a shininess value of 128.0f. Setting the value at 64.0f does not make much difference in output.

void initGL()
{
static const GLfloat light_model_ambient[] = {0.2f, 0.2f, 0.2f, 1.0f};

glLightModelfv(GL_LIGHT_MODEL_AMBIENT, light_model_ambient);

glEnable(GL_DEPTH_TEST);

float diffuse[]  = {1.0f, 1.0f, 1.0f, 1.0f};
float position[] = {5.0f, 5.0f, 5.0f, 1.0f};
float specular[] = {0.8f, 0.8f, 0.8f, 1.0f};

glEnable(GL_LIGHTING);
glEnable( GL_LIGHT0);
glLightfv(GL_LIGHT0, GL_DIFFUSE,  diffuse);
glLightfv(GL_LIGHT0, GL_POSITION, position);
glLightfv(GL_LIGHT0, GL_SPECULAR, specular);

glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

float shininess = 128.0f;
glEnable(GL_COLOR_MATERIAL);
glMaterialf( GL_FRONT_AND_BACK, GL_SHININESS, shininess);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR,  specular);

}


Could you suggest me what is going wrong with my code.

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I have been able to get better output by adding the following:

glEnable(GL_NORMALIZE);

Thank you for sharing ideas. But I have one question why textured portion remains unaffected by lighting?

Thanks again.