Can you share the code where you create the array? How are you using the faces data from the file?
This. You are sending the 8 vertices of a cube to GL, but drawing triangles that's not going to work (cube has 6 faces that are quads = 12 total triangles). You need to make a GL_ELEMENT_ARRAY buffer out of the faces section of the obj file data.
If you haven't already seen this online book, stop now and read: http://arcsynthesis.org/gltut/
I everyone, after reviewing my code and your advice I finally have a semi-working thing :)
Why do I say semi ? Because the model is loaded and I see something but there is an issue : ALL polygon seem to me drawn from the origin point.
It is supposed to be Suzanne (Blender monkey head).
What could do that ?
Draw code :
void draw(){
//matrix uniform
//pass it to shader
GLuint mID = glGetUniformLocation(programHandle, "m");
glUniformMatrix4fv(mID, 1, GL_FALSE, &model[0][0]);
GLuint vID = glGetUniformLocation(programHandle, "v");
glUniformMatrix4fv(vID, 1, GL_FALSE, &view[0][0]);
GLuint pID = glGetUniformLocation(programHandle, "p");
glUniformMatrix4fv(pID, 1, GL_FALSE, &projection[0][0]);
GLuint itID = glGetUniformLocation(programHandle, "invTransp");
glUniformMatrix4fv(itID, 1, GL_FALSE, &glm::transpose(glm::inverse(model))[0][0]);
glClear(GL_COLOR_BUFFER_BIT);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,vboIndex);
std::vector<GLuint>* order = new std::vector<GLuint>;
obj.getVertexOrder(order);
//glDisable(GL_CULL_FACE);
//glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
//glDisable(GL_LIGHTING);
//glDisable(GL_TEXTURE_2D);
glDrawElements(GL_POLYGON, order->size(), GL_UNSIGNED_INT, 0);
glFlush();
}
Thank you for your help :) I very new to opengl and it is not easy to search when that happens if I don't know how this is called xD
GL_POLYGON draws a *single* polygon. Try hitting 'triangulate' in blender before exporting to obj and rendering GL_TRIANGLES.
I did just what you said it helped a bit. I can see the face now but it is not hole/it is like the faces subtract each other.
What else should I try ?
Have you set up the depth buffer?
Needs to be enabled, cleared each frame, and the most common clear value is 1.0.
Here's a wiki page about is: http://www.opengl.org/wiki/Depth_Buffer
edit: also obj indices start at 1, need to adjust to 0 for gl elements if you haven't already.
You were right it was the depth buffer. Thank you, I thought it was enable by default. :)
