Hi, I''ve been having trouble getting texturing going in some of my apps. I downloaded the NeHe texture example, which compiles and works fine. Then I downloaded NeHe base code to try and get texturing working using its framework. Trouble is, (just like in my other applications), the texture never gets displayed. In this example I simply end up with a white spinning cube. I was hoping somone might be able to tell me what I''m doing wrong. The changes I made to the NeHe base code are fairly trivial. in app.cpp, I insert at the begining of InitGL these lines... glGenTextures(1, &g_texture); int l_x, l_y; for (l_x = 0; l_x != 64; ++l_x) { for (l_y = 0; l_y != 64; ++l_y) { int c = (((l_x & 0x8) == 0) ^ ((l_y & 0x8) == 0))*255; l_image[l_x + l_y*64] = 0xFF | (c << 16) | (c << 8) | c; } } glBindTexture(GL_TEXTURE_2D, g_texture); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 64, 64, 0, GL_RGBA, GL_UNSIGNED_BYTE, l_image); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); where l_image and g_texture are defined as... GLuint g_texture; int l_image[64*64]; in the global variables section. I then simply replaced the Draw code with that from lesson 6 (replacing texture[0] with g_texture) If anyone could help thatad be greate. I can only assume that there is some sort of OpenGL state which I am using that hasnt been set correctly. IMHO, thanks in advance for your help! - Pog

1) change ++I_x and ++I_y to I_x++ and I_y++ : array subscripting starts at count zero - you''re skipping the first pixel in the bitmap.
2) try changing I_image to char[64 * 64 * 4] and filling it in:




to see if you get a red mesh. Everything else seems correct at the first glance (okay, okay, I admit I''m too lazy to go through the color calcutlation thng thingy)

3) use [ -- source -- ] and [ -- /suorce -- ] tags to post your code (omit the dashes)

Hope this helps,
Crispy

Thanks for your help, but I''m afraid there isnt actualy anything wrong with the seduo texture I generate (ie, the bitmap on the stack).

The third part of a for loop dosnt get called until the end of an iteration, so in practice ++i is the same as i++ because you never actualy use the local result. Incrementing and then checking the loop are two seperate operations.
Infact ++i is better if your using non-atomic types, since i++ returns a temporary which can be non trivial (especialy if i is a user class).

Aside from that, I''ve tested putting the seudo image in the lesson 6 example code, works fine.

Thanks for your help though!

No offense but maybe you forgotten to enable GL_TEXTURE_2D ?