Tagged Questions

5
votes
1answer
367 views

How to do simple bump mapping

I'm trying to do bump mapping, and I'm getting fairly close at achieving my goal. I miss one crucial piece of my puzzle to have bump mapped effect in my scene; I need to transform the normals from my ...
0
votes
0answers
79 views

Efficiency of normal calculation

I've loaded a model into my program from a file. I have it rendering just fine in opengl(Using vbos, in case anyone is wondering). I have the normals loaded and applied as well, however my program is ...
8
votes
4answers
519 views

OpenGL: why do I have to set a normal with glNormal?

I'm learning some basics of OpenGL but I'm wondering why there is a call glNormal to set the normal of vertices. If I create a simple triangle like this: glBegin(GL_TRIANGLES); ...
3
votes
1answer
123 views

Can't get normals to work correctly with lighting in OpenGL [closed]

I'm trying to light up a simple 2d triangle with my cursor as a diffuse light source but can't seem to set the normal correctly for the lighting to look right. The function that calculates the normal ...
1
vote
1answer
268 views

Why isn't my lighting working properly? Are my normals messed up?

I'm relatively new to OpenGL and I am trying to draw a 3D model (loaded from a 3ds file using lib3ds) using OpenGL with lighting, but about half of it is drawn in black. I set up the light as such: ...
0
votes
3answers
939 views

Fastest solution to compute normal

A physics engine return a deformed mesh (only geometry vertices). I take this mesh to render the geometry (~500000 vertices). What is the fastest solution and the least expensive to compute normal ...
2
votes
3answers
482 views

3Ds Max is exporting model with more normals than vertices

I made a simple teapot with the "Create Standard Primitives" option and exported it as a collada file, ended up with this: < float_array id="Teapot001-POSITION-array" count="1590"> < ...
3
votes
1answer
392 views

Unusual Lighting Effects - Random Polygons Coloured

I am working on creating an object loader for use with iOS, I have managed to load the vertices, normals and face data from and OBJ file, and then place this data into arrays for reconstructing the ...
3
votes
1answer
956 views

Normal transformation and homogeneous coordinates

I'm very confused about the math behind the model/affine transformation expressed in homogeneous coordinates. Reading this article, I understood that a generic vector is transformed by multiplying it ...
1
vote
2answers
210 views

A little bit confused on how to set normals in this case

I'm learning how to use VBOs and I'm following up on the tutorial at the bottom of this page. So I went ahead and created a structure Vertex to hold vertex data.(coordinates and normals). struct ...
7
votes
6answers
778 views

Does one need normals for a strictly 2d Game?

I'm starting to learn OpenGL by creating a pure 2D game. I have to decide on the format of the Vertices. Do I need a normal component? Or is this for a 2d component not needed? My gut feeling says I ...