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Archive Notice: This thread is old and no longer active. It is here for reference purposes. This thread was created on an older version of the flipcode forums, before the site closed in 2005. Please keep that in mind as you view this thread, as many of the topics and opinions may be outdated.
 
maxam

March 20, 2005, 02:10 PM

I finally have my engine loading multiple objects and putting them into a queue for drawing. I created a test file to see how many polygons it could render and at what speed. The 3ds file contains 4 objects all the same, 25000 verts and 25000 faces totaling about 100000 faces. Now i get good results when the engine is running but I see no difference when backface culling is turned on or off. From what i understand you should just turn on BfC and get results but it would still go through its entire drawing routine and just skip the rendering of the triangles. Am i using it right?

here is my init code:

int BLUE3D::InitGL(int sw,int sh)
{
glViewport(0,0,sw,sh);

glEnable(GL_TEXTURE_2D);
glShadeModel(GL_SMOOTH);
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
glClearDepth(1.0f);

glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
//glEnable(GL_CULL_FACE);

 
timm

March 20, 2005, 02:21 PM

Put those verts in a list or something. YOu're wasting too much time calling functions.

 
Axel

March 20, 2005, 02:27 PM

As timm said using immediate OpenGL functions is sloooow
If you really want good performance then use a display list or ARB_vertex_buffer_object

 
Scali

March 20, 2005, 02:57 PM

I would like to add, that other than that you are indeed correct.
BFC simply skips the rasterization of the triangles... everything else is still done (T&L, clipping, that sort of stuff).
And just turning it on should give results... if rasterization is the bottleneck, which it isn't in your code, as pointed out above.

 
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