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JefS

OpenGL lights opengles 1

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JefS    122
This is an opengl version without shaders so i can only use the GL_LIGHT 's.

My scene contains a model with textures on it and there is 1 light.

When my light has a diffuse value of 1.0f, 0.0f, 0.0f

It is completly red ... which is normal ofcourse.

But when I set it to 0.5f, 0.0f, 0.0f ... its the same as when it was 1.0f ... no matter what value I set it, it is always fully red unless I set it to 0.0f, than it becomes black.


glEnable( GL_LIGHTING );
glEnable( GL_LIGHT0 );

GLfloat specular[] = {0.2, 0.2, 0.2, 1.0};
glLightfv(GL_LIGHT0, GL_SPECULAR, specular);

GLfloat ambient[] = {0.1, 0.1, 0.1, 1.0};
glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);

GLfloat diffuse[] = { 0.7, 0.0, 0.0, 1.0};
glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);

GLfloat position[] = {3.0, 5.0, -2.0, 0.0 };
glLightfv(GL_LIGHT0, GL_POSITION, position);


Model->Render();


glDisable( GL_LIGHTING );
glDisable( GL_LIGHT0 );


I also tried disabling the normals but that didn't help it just made the entire object red.

Edit: Ok it does work but it only works with very small values, between 0.0 and 0.1 which is very strange ? Is it because of it being a directional light? Or the object being to close to the light? Edited by JefS

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JefS    122
Lets just say i want to place a 3 point lighting in my scene, what lights should i use for that?

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V-man    813
If you are using uniform scale on your modelview matrix, use GL_RESCALE_NORMAL.
If you are using not uniform scale, GL_NORMALIZE.
That will normalize the normals of your objects so that the lighting calculations turn out correct.

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